阅读说明：本技术 用于计算患者信息的系统和方法 (System and method for calculating patient information ) 是由 冈特·沙夫 克里斯托弗·沙夫 德瑞克·任宇·周 格雷登·埃内斯特·贝蒂 R·麦克斯韦·弗莱厄 于 2019-11-08 设计创作，主要内容包括：本文提供了用于计算患者信息的系统和方法。该方法包括确定传递矩阵,经由位于第一组记录位置处的第一组记录电极来记录电势以创建第一组记录信号,以及通过将传递矩阵应用于第一组记录信号来计算一组目标位置的患者信息。传递矩阵是第一组记录位置与一组目标位置之间的组织的电特性的特征。(Systems and methods for calculating patient information are provided herein. The method includes determining a transfer matrix, recording potentials via a first set of recording electrodes located at a first set of recording locations to create a first set of recorded signals, and calculating patient information for a set of target locations by applying the transfer matrix to the first set of recorded signals. The transfer matrix is characteristic of the electrical properties of the tissue between the first set of recording locations and the set of target locations.)

1. A method of calculating information for a patient, comprising:

determining a transfer matrix;

recording potentials via a first set of recording electrodes located at a first set of recording locations to create a first set of recording signals; and

patient information for a set of target locations is calculated by applying the transfer matrix to the first set of recorded signals.

2. The method of at least one of the preceding claims, wherein the first set of recording electrodes comprises one or more electrodes.

3. The method of at least one of the preceding claims, wherein the first set of recording electrodes comprises two or more electrodes.

4. The method of at least one of the preceding claims, wherein the first set of recording electrodes comprises one or more electrodes selected from the group consisting of: body surface electrodes, in vivo electrodes, percutaneous electrodes, subcutaneous electrodes, and combinations thereof.

5. The method of at least one of the preceding claims, wherein the first set of recording electrodes comprises: at least one electrode positioned on the patient's skin, at least one electrode positioned on an endocardial surface of a heart chamber, and/or at least one electrode within a heart chamber offset from an endocardial wall of the heart chamber.

6. The method of at least one of the preceding claims, wherein the first set of electrodes comprises a set of electrodes configured to be positioned on the patient's skin, and the first set of electrodes comprises a material selected from the group consisting of: platinum iridium, gold, polymers such as polymer coatings, carbon, copper, silver-silver chloride, conductive gels, and combinations thereof.

7. The method of at least one of the preceding claims, wherein the first set of electrodes comprises a set of electrodes configured to be positioned within the patient's body, and the first set of electrodes comprises a material selected from the group consisting of: platinum iridium, gold, polymers such as polymer coatings, carbon, and combinations thereof.

8. The method of at least one of the preceding claims, wherein the first set of recording electrodes comprises one, two or more electrodes selected from: one or more electrodes configured to transmit and/or receive a localization signal; a plurality of electrodes configured to produce an ECG signal, such as an ECG array comprising at least 9 or at least 12 electrodes; a plurality of electrodes configured to generate a high density ECGi signal; one or more electrodes configured to deliver cardiac pacing energy; one or more electrodes configured to deliver defibrillation energy; one or more electrodes configured to deliver therapeutic energy; and combinations thereof.

9. The method of claim 8, wherein the one, two, or more electrodes are positioned on and/or within patient clothing.

10. The method of claim 9, wherein the patient garment comprises a garment selected from the group consisting of: vests, shirts, belts, and combinations thereof.

11. The method of at least one of the preceding claims, wherein the first set of recording electrodes is positioned on and/or within a patient garment.

12. The method of claim 11, wherein the patient garment comprises a garment selected from the group consisting of: vests, shirts, belts, and combinations thereof.

13. The method of claim 11, wherein the first set of recording electrodes is positioned in a vertical arrangement, a horizontal arrangement, a diagonal arrangement, and/or a helical arrangement relative to the patient.

14. The method of claim 11, wherein the first set of electrodes are positioned on and/or within the patient garment in a defined pattern, wherein the pattern defines a coordinate system.

15. The method of claim 11, wherein the first set of electrodes is configured to provide:

monitoring arrhythmia; positioning of a device positioned within the patient; and/or an electrical information map of the patient's heart such as voltage information, dipole density information, and/or surface charge information.

16. The method of at least one of the preceding claims, wherein the first set of recording locations comprises one or more locations on the patient's skin.

17. The method of claim 16, wherein the first set of recording locations comprises locations selected from the group consisting of: chest, back, torso, shoulders, abdomen, skull, face, arms, legs, groin, and combinations thereof.

18. The method of claim 16, wherein the set of target locations further comprises one or more locations within the patient.

19. The method of claim 18, wherein the one or more locations within the patient's body comprise locations proximate the patient's heart.

20. The method of claim 19, wherein the one or more locations within the patient's body comprise one or more locations selected from the group consisting of: epicardial surface, within cardiac tissue, endocardial surface, within the heart chamber, pericardial cavity, pericardium, and combinations thereof.

21. The method of at least one of the preceding claims, wherein the first set of recording locations includes one or more locations within the patient.

22. The method of claim 21, wherein the first set of recording locations includes one or more in vivo locations selected from the group consisting of: intracardiac, endocardial, epicardial, and combinations thereof.

23. The method of claim 21, wherein the first set of recording locations includes one or more in vivo locations selected from the group consisting of: the tissue can include, but is not limited to, esophagus, epicardium, pericardium, interstitial fluid and/or other tissue structures surrounding the heart, interstitial fluid and/or other tissue structures under the skin, subcutaneous tissue, spinal tissue, brain tissue, and combinations thereof.

24. The method of claim 21, wherein the first set of recording locations includes one or more locations within and/or otherwise proximate to the patient's heart.

25. The method of claim 24, wherein the first set of recording locations includes one or more locations selected from: epicardial surface, within cardiac tissue, endocardial surface, within the heart chamber, pericardial space, pericardium, and combinations thereof.

26. The method of at least one of the preceding claims, wherein the first set of recording locations comprises locations on the patient's skin and locations within the patient's body.

27. The method of claim 26, wherein system is configured to multiplex signal sources and receivers between electrodes on the patient's skin and recording electrodes within the patient's body.

28. The method of at least one of the preceding claims, wherein the calculated patient information comprises information selected from the group consisting of: electrical information, voltage information, surface charge information, tissue charge information, dipole density information, tissue density information, electrogram flow information, impedance information, phase information, and combinations thereof.

29. The method of at least one of the preceding claims, wherein the calculated patient information includes tissue density information.

30. The method of claim 29, wherein the tissue density information includes information related to a change in tissue density over time.

31. The method of claim 30, wherein the change in tissue density over time comprises a change caused by ablation of the tissue.

32. The method of at least one of the preceding claims, wherein the transfer matrix includes characteristics of electrical properties of tissue between the first set of recording locations and the set of target locations.

33. The method of at least one of the preceding claims, wherein determining the transfer matrix comprises:

transmitting a set of drive signals via a set of drive electrodes located at a set of drive positions; and

recording the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recording signals;

wherein the transfer matrix is determined by comparing the second set of recording signals with the transmitted set of drive signals.

34. The method of claim 33, wherein the set of drive electrodes comprises one or more electrodes.

35. The method of claim 34, wherein the set of drive electrodes comprises two or more electrodes.

36. The method of claim 35, wherein the two or more electrodes are positioned at least 2mm from each other.

37. The method of claim 33, wherein the set of drive electrodes is positioned on and/or within a patient garment.

38. The method of claim 37, wherein the patient garment comprises a garment selected from the group consisting of: vests, shirts, belts, and combinations thereof.

39. The method of claim 33, wherein the set of actuation positions comprises positions within the patient.

40. The method of claim 39, wherein the set of drive positions comprises positions selected from: within a chamber of the heart, an endocardial surface, an epicardial surface, a pericardial cavity, an esophagus, and combinations thereof.

41. The method of claim 39, wherein the set of actuation positions comprises positions inside the heart.

42. The method of claim 39, wherein the second set of recorded locations comprises locations on the patient's skin.

43. The method of claim 33, wherein the set of drive positions includes positions on the patient's skin.

44. The method of claim 43, wherein the set of actuation positions includes skin positions selected from the group consisting of: chest, back, torso, shoulders, abdomen, thorax, and combinations thereof.

45. The method of claim 43, wherein the second set of recorded locations comprises locations within the patient.

46. The method of claim 45, wherein the second set of recording locations comprises locations selected from the group consisting of: intracardiac, endocardial, epicardial, pericardial, esophageal, interstitial fluid and/or other tissue structures surrounding the heart, subcutaneous, spinal, brain tissue, and combinations thereof.

47. The method of claim 33, wherein the drive signal comprises:

a first drive signal at a first frequency from a first drive electrode; and

a second drive signal at a second frequency from a second drive electrode;

wherein the first frequency and the second frequency are different.

48. The method of claim 47, wherein the first drive signal and the second drive signal are delivered simultaneously.

49. The method of claim 33, wherein the drive signal comprises:

a first drive signal at a first frequency from a first drive electrode; and

a second drive signal at a second frequency from a second drive electrode;

wherein the first drive signal and the second drive signal are delivered sequentially.

50. The method of claim 49, wherein the first frequency and the second frequency are the same frequency.

51. The method of claim 33, wherein the transfer matrix is determined using the amplitude and/or phase of the second set of recorded signals.

52. A method according to claim 51, wherein the transfer matrix comprises a numerical scaling factor based on a comparison of the amplitude and/or phase of the second set of recording signals with the amplitude and/or phase of the set of drive signals.

53. The method of claim 51, wherein the transfer matrix is determined using the amplitude and phase of the second set of recorded signals.

54. The method of claim 33, wherein the emitting of the set of drive signals and the recording of the emitted drive signals occurs during at least one physiological cycle of the patient.

55. The method of claim 54, wherein the physiological cycle comprises a cycle selected from the group consisting of: cardiac cycles, respiratory cycles, pressure cycles, and combinations thereof.

56. The method of claim 54, wherein the delivery matrix compensates for the patient's breathing.

57. The method of claim 54, wherein the transfer matrix compensates for cardiac motion of the patient.

58. The method according to claim 54, wherein the transfer matrix comprises a time-dependent transfer matrix including one or more components/factors that vary in correspondence with the physiological cycle.

59. The method according to claim 58, wherein calculating the calculated patient information includes aligning the time-dependent transfer matrix with the physiological cycle.

60. The method of claim 33, wherein the transfer matrix adapts proportionally over time.

61. The method of claim 33, wherein determining the transfer matrix further comprises combining information from the calculated and/or selected normalized transfer matrices.

62. The method of at least one of the preceding claims, wherein determining the transfer matrix comprises calculating and/or selecting a normalized transfer matrix.

63. The method of claim 62, wherein the normalized transfer matrix is selected based on patient parameters.

64. The method of claim 63, wherein the patient parameters include parameters selected from the group consisting of: gender, weight, height, body or body part size, Body Mass Index (BMI), chest circumference, location of esophagus, size of atrium, filling of atrium volume, atrial pressure, ratio of fat to water, ratio of air to water to fat, bone location, medication taken, medication level, electrolyte level, pH, pO₂、pCO₂Weight of water, and combinations thereof.

65. The method of at least one of the preceding claims, wherein the transfer matrix is modified over time.

66. The method of claim 65, wherein the delivery matrix is modified based on at least one changing patient parameter.

67. The method of claim 66, wherein the at least one varied patient parameter comprises at least two varied patient parameters, wherein the delivery matrix is modified based on the at least two varied patient parameters.

68. The method of claim 66, wherein the varying patient parameter comprises at least one periodically varying patient parameter, wherein the transfer matrix is modified based on the at least one periodically varying patient parameter.

69. The method of claim 66, wherein the transfer matrix is modified to compensate for the patient's breathing.

70. The method of claim 66, wherein the transfer matrix is modified to compensate for the patient's cardiac motion.

71. The method of claim 66, further comprising monitoring the at least one changing patient parameter.

72. The method of claim 71, wherein said monitoring comprises continuous monitoring of said at least one varying patient parameter.

73. The method of claim 72, wherein the transfer matrix is continuously modified.

74. The method of claim 71, wherein the monitoring comprises intermittent monitoring of the at least one varying patient parameter.

75. The method of claim 74 in which the transfer matrix is modified intermittently.

76. The method of at least one of the preceding claims, wherein applying the transfer matrix to the first set of recording signals comprises applying a linear geometric function of the transfer matrix to the first set of recording signals.

77. The method of at least one of the preceding claims, further comprising collecting patient physiological data.

78. The method of claim 77, wherein the patient physiological data comprises data selected from the group consisting of: physiological cycle data, cardiac data, respiratory data, patient medication data, skin impedance data, perspiration data, thoracic and/or abdominal space data, water weight data, hematocrit level data, wall thickness data, cardiac wall thickness data, and combinations thereof.

79. The method of claim 77, wherein the patient physiological data is collected by at least one sensor.

80. The method of claim 79, wherein the patient physiological data is collected by at least two sensors.

81. The method of claim 79, wherein the at least one sensor comprises one, two, three, or more sensors selected from: magnetic sensor, water sensor, perspiration sensor, skin impedance sensor, glucose sensor, pH sensor, PO₂Sensor and pCO₂Sensor, SpO₂Sensors, heart rate sensors, pressure sensors, blood pressure sensors, spine sensors, brain electrodes, brain sensors, flow sensors, blood flow sensors, motion sensors, and combinations thereof.

82. The method of claim 79, wherein the at least one sensor is positioned on and/or within a patient garment.

83. The method of claim 82, wherein the patient garment comprises a garment selected from the group consisting of: vests, shirts, belts, and combinations thereof.

84. The method of claim 77, further comprising identifying changes in physiological data over time, and modifying the transfer matrix based on the identified changes.

85. The method of at least one of the preceding claims, further comprising:

recording the voltage of the patient at the alpha position; and

determining electrical information at a beta position, wherein the beta position is a different position than the alpha position.

86. The method of claim 85, wherein the determined electrical information is based on an inverse solution output, wherein the transfer matrix is applied to improve a quality of the determined electrical information.

87. The method of claim 86, wherein the transfer matrix accounts for spatial anisotropy and/or temporal anisotropy.

88. The method of at least one of the preceding claims, further comprising:

a device location operation is performed to determine device location information.

89. The method of claim 88, wherein the transfer matrix is applied to improve the quality of the determined device location information.

90. The method of claim 89, further comprising performing a real-time update of the positioning data.

91. The method of at least one of the preceding claims, wherein applying the transfer matrix comprises: applying a ratiometric function of the transfer matrix to the first set of recorded signals.

92. The method of claim 91, wherein the ratiometric function comprises an identity function, wherein the patient information is calculated using only the transfer matrix.

93. The method of claim 91, wherein the ratiometric function is configured to linearly scale the transfer matrix.

94. The method of claim 91, wherein the ratiometric function is configured to non-linearly scale the transfer matrix.

95. The method of at least one of the preceding claims, wherein applying the transfer matrix to the first set of recording signals comprises applying a non-linear geometric function of the transfer matrix to the first set of recording signals.

96. The method of at least one of the preceding claims, wherein calculating the patient information by applying the transfer matrix does not include the use of an inverse solution.

Technical Field

The present invention relates generally to a medical diagnostic and treatment system, and more particularly to a system that records physiological data from a first location to provide patient information at a different location.

Background

Systems used by clinicians to perform medical procedures, such as diagnostic and/or therapeutic procedures, often require evaluation of one or more patient parameters, such as electrical and/or mechanical properties of tissue, as well as other patient information useful in performing the medical procedure. Among other things, the procedure of treating (e.g., ablating) tissue typically includes an assessment of untreated tissue (e.g., prior to treatment), partially treated tissue (e.g., during treatment), and/or treated tissue (e.g., after treatment). Due to limited space and other reasons, it is often difficult to assess at the treatment site. The accuracy and specificity of the available assessments may be limited and result in a lack of safety and/or a lack of effectiveness of the treatment.

There is a need for a system that provides tissue and other patient information in a secure, efficient, reliable, and simplified manner.

Disclosure of Invention

According to one aspect of the inventive concept, a method of calculating information of a patient includes: determining a transfer matrix; recording potentials via a first set of recording electrodes located at a first set of recording locations to create a first set of recording signals; and calculating patient information for a set of target locations by applying the transfer matrix to the first set of recorded signals.

In some embodiments, the first set of recording electrodes includes one or more electrodes.

In some embodiments, the first set of recording electrodes includes two or more electrodes.

In some embodiments, the first set of recording electrodes comprises one or more electrodes selected from the group consisting of: body surface electrodes, in vivo electrodes, percutaneous electrodes, subcutaneous electrodes, and combinations thereof.

In some embodiments, the first set of recording electrodes comprises: at least one electrode positioned on the skin of the patient, at least one electrode positioned on an endocardial surface of the heart chamber, and/or at least one electrode within the heart chamber offset from an endocardial wall of the heart chamber.

In some embodiments, the first set of electrodes comprises: a set of electrodes configured to be positioned on the skin of a patient and comprising a material selected from the group consisting of: platinum iridium, gold, polymers (e.g., polymer coatings), carbon, copper, silver-silver chloride, conductive gels, and combinations thereof.

In some embodiments, the first set of electrodes comprises: a set of electrodes configured to be positioned within a body of a patient and comprising a material selected from the group consisting of: platinum iridium, gold, a polymer (e.g., a polymer coating), carbon, and combinations thereof.

In some embodiments, the first set of recording electrodes comprises one, two or more electrodes selected from: one or more electrodes configured to transmit and/or receive positioning signals, a plurality of electrodes configured to produce ECG signals (such as an ECG array of at least 9 or at least 12 electrodes), a plurality of electrodes configured to produce a high density ECGi signal, one or more electrodes configured to deliver cardiac pacing energy, one or more electrodes configured to deliver defibrillation energy, one or more electrodes configured to deliver therapeutic energy, and combinations thereof. One, two, or more electrodes may be positioned on and/or within the patient garment. The patient garment may comprise a garment selected from: vests, shirts, belts, and combinations thereof.

In some embodiments, the first set of recording electrodes is positioned on and/or within the patient garment. The patient garment may comprise a garment selected from: vests, shirts, belts, and combinations thereof. The first set of recording electrodes may be positioned in a vertical arrangement, a horizontal arrangement, a diagonal arrangement, and/or a helical arrangement relative to the patient. The first set of electrodes may be positioned on and/or within the patient garment in a defined pattern, and the pattern may define a coordinate system. The first set of electrodes may be configured to provide: arrhythmia monitoring, positioning of a device positioned within a patient, and/or mapping of electrical information (such as voltage information, dipole density information, and/or surface charge information) of the patient's heart.

In some embodiments, the first set of recording locations includes one or more locations on the skin of the patient. The first set of recording locations may comprise locations selected from: chest, back, torso, shoulders, abdomen, skull, face, arms, legs, groin, and combinations thereof. The set of target locations may also include one or more locations within the patient. The one or more locations within the patient's body may include a location proximate the patient's heart. The one or more locations within the patient's body may include one or more locations selected from the group consisting of: epicardial surface, within cardiac tissue, endocardial surface, within the heart chamber, pericardial space, pericardium, and combinations thereof.

In some embodiments, the first set of recording locations includes one or more locations within the patient. The first set of recording locations may include one or more in vivo locations selected from the group consisting of: intracardiac, endocardial, epicardial, and combinations thereof. The first set of recording locations may include one or more in vivo locations selected from the group consisting of: the tissue can include, but is not limited to, esophagus, epicardium, pericardium, interstitial fluid and/or other tissue structures surrounding the heart, interstitial fluid and/or other tissue structures under the skin, subcutaneous tissue, spinal tissue, brain tissue, and combinations thereof. The first set of recording locations may include one or more locations within and/or otherwise proximate to the patient's heart. The first set of recording locations may include one or more locations selected from the group consisting of: epicardial surface, within cardiac tissue, endocardial surface, within the heart chamber, pericardial space, pericardium, and combinations thereof.

In some embodiments, the first set of recorded locations includes locations on the skin of the patient and locations within the body of the patient. The system may be configured to multiplex the signal source and receiver between electrodes on the skin of the patient and recording electrodes within the patient.

In some embodiments, the calculated patient information includes information selected from the group consisting of: electrical information, voltage information, surface charge information, tissue charge information, dipole density information, tissue density information, electrogram flow information, impedance information, phase information, and combinations thereof.

In some embodiments, the calculated patient information includes tissue density information. The tissue density information may include information related to the change in tissue density over time. The change in tissue density over time may include a change caused by ablation of the tissue.

In some embodiments, the transfer matrix includes characteristics of electrical properties of tissue between the first set of recording locations and the set of target locations.

In some embodiments, determining the transfer matrix comprises: transmitting a set of drive signals via a set of drive electrodes located at a set of drive positions; and recording the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recording signals. The transfer matrix may be determined by comparing the second set of recording signals with the transmitted set of drive signals. The set of drive electrodes may include one or more electrodes. The set of drive electrodes may comprise two or more electrodes. Two or more electrodes may be positioned at least 2mm from each other. The set of drive electrodes may be positioned on and/or within the patient garment. The patient garment may comprise a garment selected from: vests, shirts, belts, and combinations thereof. The set of actuation positions may include positions within the patient. The set of drive positions may include positions selected from: within a chamber of the heart, an endocardial surface, an epicardial surface, a pericardial cavity, an esophagus, and combinations thereof. The set of actuation positions may include positions within the heart. The second set of recorded locations may comprise locations on the skin of the patient. The set of actuation positions may include positions on the skin of the patient. The set of actuation positions may include skin positions selected from the group consisting of: chest, back, torso, shoulders, abdomen, thorax, and combinations thereof. The second set of recorded locations may include locations within the patient. The second set of recording locations may comprise locations selected from: intracardiac, endocardial, epicardial, pericardial, esophageal, interstitial fluid and/or other tissue structures surrounding the heart, subcutaneous, spinal, brain tissue, and combinations thereof. The driving signal may include: a first drive signal at a first frequency from the first drive electrode, and a second drive signal at a second frequency from the second drive electrode. The first frequency and the second frequency may be different. The first drive signal and the second drive signal may be delivered simultaneously. The driving signal may include: a first drive signal at a first frequency from the first drive electrode, and a second drive signal at a second frequency from the second drive electrode. The first drive signal and the second drive signal may be delivered sequentially. The first frequency and the second frequency may be the same frequency. The amplitude and/or phase of the second set of recorded signals may be used to determine the transfer matrix. The transfer matrix may comprise a numerical scaling factor based on a comparison of the amplitude and/or phase of the second set of recording signals with the amplitude and/or phase of the set of drive signals. The amplitude and phase of the second set of recorded signals may be used to determine the transfer matrix. The emitting of the set of drive signals and the recording of the emitted drive signals may occur during at least one physiological cycle of the patient. The physiological cycle may include a cycle selected from: cardiac cycles, respiratory cycles, pressure cycles, and combinations thereof. The transfer matrix may compensate for the patient's breathing. The transfer matrix may compensate for the patient's cardiac motion. The transfer matrix may comprise a time-dependent transfer matrix comprising one or more components/factors that vary in correspondence with the physiological cycle. Calculating the calculated patient information may include aligning the time-dependent transfer matrix with the physiological cycle. The transfer matrix may be adapted proportionally over time. Determining the transfer matrix may also include combining information from the calculated and/or selected normalized transfer matrices.

In some embodiments, determining the transfer matrix includes calculating and/or selecting a normalized transfer matrix. The normalized delivery matrix may be selected based on patient parameters. The patient parameters may include parameters selected from the group consisting of: gender, weight, height, body or body part size, Body Mass Index (BMI), chest circumference, location of esophagus, size of atrium, filling of atrium volume, atrial pressure, ratio of fat to water, ratio of air to water to fat, bone location, medication taken, medication level, electrolyte level, pH, pO₂、pCO₂Weight of water, and combinations thereof.

In some embodiments, the transfer matrix is modified over time. The delivery matrix may be modified based on the at least one changed patient parameter. The at least one varied patient parameter may include at least two varied patient parameters, and the transfer matrix may be modified based on the at least two varied patient parameters. The varying patient parameter may include at least one periodically varying patient parameter, and the transfer matrix may be modified based on the at least one periodically varying patient parameter. The transfer matrix may be modified to compensate for the patient's breathing. The transfer matrix may be modified to compensate for the patient's cardiac motion. The method may further comprise monitoring at least one changing patient parameter. The monitoring may comprise continuous monitoring of at least one changing patient parameter. The transfer matrix may be continuously modified. The monitoring may comprise intermittent monitoring of the at least one changing patient parameter. The transfer matrix may be intermittently modified.

In some embodiments, applying the transfer matrix to the first set of recorded signals includes applying a linear geometric function of the transfer matrix to the first set of recorded signals.

In some embodiments, the method further comprises collecting patient physiological data. The patient physiological data may include data selected from the group consisting of: physiological cycle data, cardiac data, respiratory data, patient medication data, skin impedance data, perspiration data, thoracic and/or abdominal space data, water weight data, hematocrit level data, wall thickness data, cardiac wall thickness data, and combinations thereof. Patient physiological data may be collected by at least one sensor. Patient physiological data may be collected by at least two sensors. The at least one sensor may comprise one, two, three or more sensors selected from: magnetic sensor, water sensor, perspiration sensor, skin impedance sensor, glucose sensor, pH sensor, PO₂Sensor and pCO₂Sensor, SpO₂Sensors, heart rate sensors, pressure sensors, blood pressure sensors, spine sensors, brain electrodes, brain sensors, flow sensors, blood flow sensors, motion sensors, and combinations thereof. The at least one sensor may be positioned on and/or within the patient garment. The patient garment may comprise a garment selected from: vests, shirts, belts, and combinations thereof. The method may also include identifying a change in the physiological data over time, and may modify the transfer matrix based on the identified change.

In some embodiments, the method further comprises: recording the voltage of the patient at the alpha position; and determining electrical information at the beta position. The β position may be a position different from the α position. The determined electrical information may be based on the output of the inverse solution, and a transfer matrix may be applied to improve the quality of the determined electrical information. The transfer matrix may take into account spatial anisotropy and/or temporal anisotropy.

In some embodiments, the method further comprises performing a device location operation to determine device location information. The transfer matrix may be applied to improve the quality of the determined device location information. The method may further comprise performing a real-time update of the positioning data.

The techniques described herein, together with their attributes and attendant advantages, will be best understood and appreciated by reference to the following detailed description, taken in conjunction with the accompanying drawings, in which representative embodiments are depicted by way of example.

Drawings

FIG. 1 shows a schematic diagram of a system for calculating information related to one or more parameters of a patient, consistent with the present inventive concept.

FIG. 1A illustrates a schematic diagram of a system for calculating information related to one or more parameters of a patient's heart, consistent with the present concepts.

Fig. 2 illustrates a flow chart of a method of calculating patient information using a transfer matrix based on recorded signals, consistent with the present inventive concept.

Fig. 3 illustrates a flow chart of a method of determining a transfer matrix based on recorded signals and using the transfer matrix to calculate patient information, consistent with the present inventive concept.

Detailed Description

Reference will now be made in detail to embodiments of the present technology, examples of which are illustrated in the accompanying drawings. Like reference numerals may be used to refer to like parts. However, this description is not intended to limit the disclosure to the particular embodiments, and it should be construed as including various modifications, equivalents, and/or alternatives to the embodiments described herein.

It will be understood that, as used herein, the words "comprise" (and any form of comprise, such as "comprises" and "comprises"), "have" (and any form of having, such as "has" and "has"), "include" (and any form of including, such as "includes" and "includes") or "contain" (and any form of containing, such as "contains" and "contains") specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It will be further understood that, although the terms first, second, third, etc. may be used herein to describe various limitations, elements, components, regions, layers and/or sections, these limitations, elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one limitation, element, component, region, layer or section from another limitation, element, component, region, layer or section. Thus, a first limitation, element, component, region, layer or section discussed below could be termed a second limitation, element, component, region, layer or section without departing from the teachings of the present application.

It will also be understood that when an element is referred to as being "on," "attached to," "connected to" or "coupled to" another element, it can be directly on or over the other element or directly connected or coupled to the other element or one or more intervening elements may be present. In contrast, when an element is referred to as being "directly on," "directly attached," "directly connected," or "directly coupled" to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).

It will also be understood that when a first element is referred to as being "in," "on" and/or "within" a second element, the first element can be positioned: within an interior space of the second member, within a portion of the second member (e.g., within a wall of the second member); positioned on the outer surface and/or the inner surface of the second element; and combinations of one or more of these.

As used herein, the term "proximate" when used to describe that a first component or location is proximate to a second component or location is to be taken to include one or more locations proximate to, on and/or within the second component or location. For example, a component positioned proximate to an anatomical site (e.g., a target tissue location) shall include a component positioned proximate to the anatomical site, as well as a component positioned in, on, and/or within the anatomical site.

Spatially relative terms, such as "below," "lower," "below," "over," "upper," and the like, may be used to describe elements and/or characteristic relationships to another element(s) and/or feature(s), as illustrated, for example, in the figures. It will also be understood that the spatially relative terms are intended to encompass different orientations of the device in use and/or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" and/or "beneath" other elements or features would then be oriented "above" the other elements or features. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terms "reduce," "decrease," "reducing," and the like as used herein include a reduction in number, including to zero. Reducing the likelihood of occurrence will include preventing occurrence. Accordingly, the terms "prevent," "prevent," and "prevent" shall include the actions of "decrease," "decrease," and "decrease," respectively.

The term "and/or" as used herein should be considered a specific disclosure of each of the two specified features or components, with or without the other. For example, "a and/or B" shall be considered a specific disclosure of each of (i) a, (ii) B, and (iii) a and B, as if each were individually recited herein.

The term "one or more" as used herein may refer to one, two, three, four, five, six, seven, eight, nine, ten or more, up to any number.

The terms "and combinations thereof" and combinations of these "may each be used herein after a list of items included individually or collectively. For example, a component, process, and/or other item selected from: A. b, C, and combinations thereof, will include a set of one or more components including: one, two, three or more of items a; one, two, three or more of items B; and/or one, two, three, or more of item C.

In this specification, "and" may mean "or", and "or" may mean "and", unless explicitly stated otherwise. For example, if a feature is described as having A, B or C, the feature may have any combination of A, B and C, or A, B and C. Similarly, if a feature is described as having A, B and C, the feature may have only one or both of A, B or C.

The expression "configured (or set)" used in the present disclosure may be used interchangeably with, for example, the expressions "adapted", "having capability", "designed", "adapted", "made" and "capable", depending on the situation. The expression "configuration (or setting)" does not mean only "special design" in hardware. Alternatively, in some cases, the expression "a device is configured to" may mean that the device "may" operate with another device or component.

As used herein, the term "threshold" refers to a maximum level, a minimum level, and/or a range of values associated with a desired or undesired state. In some embodiments, the system parameters are maintained above a minimum threshold, below a maximum threshold, within a threshold range of values, and/or outside of a threshold range of values to cause a desired effect (e.g., effective treatment) and/or to prevent or otherwise reduce (hereinafter "prevent") undesirable events (e.g., device and/or clinical adverse events). In some embodiments, the system parameter is maintained above a first threshold (e.g., above a first temperature threshold to cause a desired therapeutic effect on the tissue) and below a second threshold (e.g., below a second temperature threshold to prevent undesired tissue damage). In some embodiments, the threshold is determined to include a safety margin to account for patient variability, system variability, tolerance, and the like. As used herein, "exceeding a threshold" relates to a parameter exceeding a maximum threshold, being below a minimum threshold, being within a threshold range, and/or being outside a threshold range.

The term "diameter" as used herein to describe non-circular geometries is considered to be the diameter of an imaginary circle approximating the geometry described. For example, when describing a cross-section (such as a cross-section of a component), the term "diameter" should be taken to mean the diameter of an imaginary circle having the same cross-sectional area as the cross-section of the component being described.

As used herein, the terms "major axis" and "minor axis" of a component are the length and diameter, respectively, of an imaginary cylinder of minimum volume that can completely surround the component.

As used herein, the term "functional element" is considered to include one or more elements that are constructed and arranged to perform a function. The functional element may comprise a sensor and/or a transducer. In some embodiments, the functional element (e.g., a functional element configured as a treatment element) is configured to deliver energy and/or otherwise treat tissue. Alternatively or additionally, the functional element (e.g., the functional element comprising the sensor) may be configured to record one or more parameters, such as patient physiological parameters, patient anatomical parameters (e.g., tissue geometry parameters), patient environmental parameters, and/or system parameters. In some embodiments, the sensors or other functional elements are configured to perform diagnostic functions (e.g., collect data for performing diagnostics). In some embodiments, the functional element is configured to perform a therapeutic function (e.g., to deliver therapeutic energy and/or therapeutic agents). In some embodiments, the functional element comprises one or more elements constructed and arranged to perform a function selected from the group consisting of: delivering energy, extracting energy (e.g., to cool a component), delivering a drug or other agent, manipulating a system component or patient tissue, recording or otherwise sensing a parameter such as a patient physiological parameter or a system parameter, and combinations of one or more of these. "functional components" may include components constructed and arranged to perform functions such as diagnostic and/or therapeutic functions. The functional components may include extensible components. The functional component may comprise one or more functional elements.

The term "transducer" as used herein includes any component or combination of components that receives energy or any input and produces an output. For example, the transducer may include electrodes that receive electrical energy and distribute the electrical energy to the tissue (e.g., based on the size of the electrodes). In some configurations, the transducer converts the electrical signal to any output, such as light (e.g., the transducer comprises a light emitting diode or a light bulb), sound (e.g., the transducer comprises a piezoelectric crystal configured to deliver ultrasonic energy), pressure, thermal energy, cryogenic energy, chemical energy, mechanical energy (e.g., the transducer comprises a motor or a solenoid), magnetic energy, and/or a different electrical signal (e.g., bluetooth or other wireless communication element). Alternatively or additionally, the transducer may convert a physical quantity (e.g., a change in a physical quantity) into an electrical signal. The transducer may include any component that delivers energy and/or medicament to tissue, such as a transducer configured to deliver one or more of: electrical energy to tissue (e.g., the transducer comprises one or more electrodes), optical energy to tissue (e.g., the transducer comprises a laser, a light emitting diode, and/or an optical component such as a lens or prism), mechanical energy to tissue (e.g., the transducer comprises a tissue-manipulating element), acoustic energy to tissue (e.g., the transducer comprises a piezoelectric crystal), chemical energy, electromagnetic energy, magnetic energy, and combinations of one or more of these.

As used herein, the term "mapping operation" shall include a clinical operation performed on a patient that produces electrical activity information related to patient tissue, such as organ tissue (e.g., brain or heart tissue).

As used herein, the term "positioning operation" shall include the process of establishing a coordinate system and using one or more signals, such as electrical signals, to determine the position of one or more objects or portions of objects (herein "objects") within the system. In some embodiments, the localization process incorporates one or more signals generated from one or more sources (e.g., electrodes) that vary as a function of space and/or time, and incorporates sensors (e.g., electrodes) that measure the generated signals from the recorded locations. The recorded position of the sensor may be on the object being located, or the recorded position of the sensor may be separate from the object being located. The analysis of the measured signals and/or the calculations performed on the measured signals may be used to determine the positional relationship of the sensor and/or the object to one or more sources of the generated signals. The localization method may combine two or more generated signals to increase the number or accuracy of the positional relationships between the sensors and the signal sources. The sensor and the object may be a single component and/or the sensor and the object may be co-located components. In some embodiments, the change in the signal as a function of time and/or space comprises an interaction of the signal with a measurement environment. In other embodiments, the locating process measures an intrinsic or an existing characteristic of the object, the sensor, or the measurement environment, for example, by measuring a signal from an accelerometer located on the object or the sensor and incorporating information from the accelerometer signal into the analysis.

As used herein, the term "ablation procedure" shall include an ablation therapy procedure performed on patient tissue that has been identified as contributing to undesirable electrical activity, such as activity associated with cardiac arrhythmias (e.g., atrial fibrillation) or undesirable states of the brain (e.g., seizures or tremors).

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. For example, it will be understood that all features set forth in any claim (whether independent or dependent) may be combined in any given way.

It is to be understood that at least some of the figures and descriptions of the present invention have been simplified to focus on elements that are relevant for a clear understanding of the present invention, while eliminating, for purposes of clarity, other elements that those of ordinary skill in the art will appreciate may also include a portion of the present invention. However, because such elements are well known in the art, and because they do not necessarily facilitate a better understanding of the present invention, a description of such elements is not provided herein.

Systems and methods for calculating patient information are provided herein. Patient physiological data is recorded at one or more recording locations, and patient information at one or more target locations, which may be remote from the recording locations, is determined using a transfer matrix. The electrical information may be recorded by electrodes placed on the patient's skin and/or within the patient's body, and the electrical and/or other patient information may be calculated at a target location, such as where the target location includes a patient organ (e.g., heart or brain). The system of the inventive concept may include means for determining a transfer matrix, such as electrodes or other sensors characterizing tissue properties between the recording location and the target location, characteristics performed on the patient and/or one or more similar mammalian subjects for which patient information is to be calculated.

Referring now to fig. 1, a schematic diagram of a system for calculating information related to one or more parameters of a patient consistent with the present inventive concept is shown. The system 10 includes a recording assembly 300, recording electrodes 311; the recording component 300 is configured to receive information from a set of one or more sensors; each of the recording electrodes 311 is placed at one or more associated recording locations 312 of a patient, such as patient P1 as shown. The system 10 may also include a console 200, the console 200 including a processing unit 250, the processing unit 250 receiving signals generated by the recording electrodes 311 via the recording assembly 300 and storing (e.g., in the electronic memory 252) an associated recording signal 313. The processing unit 250 includes an algorithm 255 and a transfer matrix 290. The processing unit 250 may be configured to cause the algorithm 255 to apply the transfer matrix 290 to convert the recorded signals 313 into calculated patient information 95, wherein the information 95 represents patient physiological parameter information at one or more patient locations 90 (e.g., one or more skin locations and/or one or more interior locations of the patient).

The transfer matrix 290 is the (all applicable) tissue, volume V_XIs adapted to be based on at one or more recording locations 312The recordings made determine patient information 95 at one or more patient locations 90. The recording location 312 and the individual patient location 90 define an intermediate volume (e.g., a tissue volume and/or an inflation volume), a volume V_I1In which volume V_I1Defined by the space within a set of points (e.g., convex hull) collectively represented by the recording location 312 and the patient location 90. Note that in some embodiments, one or more patient locations 90 are located within a tissue region or volume (herein "region" or "volume") defined only by the recording location 312. The patient information 95 calculated at the single patient position 90 is highly dependent on the volume V_I1Tissue and/or other materials. The calculated patient information 95 also depends (albeit less) on the volume V at which the primary effect is_I1Outside, but in relation to the volume V_I1Approximate volume V_P1. Total effective volume, volume V_T1From the main active volume V_I1With volume V_P1Are defined in combination. Volume V_XMay comprise one or more volumes V_T1(e.g., volume V for each patient position 90_T1) So that each volume V_T1Are all volume V_XA subset of (a).

Volume V_XMay include various forms of tissue (e.g., skin, subcutaneous tissue, vascular wall tissue, blood, heart and/or other organ tissue, bone and/or bone marrow), interstitial spaces, and/or open spaces (e.g., spaces within a patient's lungs). The transfer matrix 290 may be configured to account for changes in tissue and/or from the volume V_XOther changes from one location to another. Volume V_XTime-varying volumes may be included, such as volumes that vary during a cardiac cycle (e.g., due to expansion and contraction of the heart and subsequent movement of surrounding tissue) and/or volumes that vary during a respiratory cycle (e.g., due to expansion and contraction of the lungs and subsequent movement of surrounding tissue). The transfer matrix 290 may be configured to consider the volume V_XOf the time-varying volume of (a). Volume V_XMay include tissue having one or more tissue parameters, as shown by tissue parameter information 80 that varies over time, such as: impedance over time (e.g. due to respiration)Induced impedance change), pH, temperature, pO₂And/or pCO₂. The transfer matrix 290 may be configured to consider the volume V_XTime variations of these tissue parameters. In some embodiments, the transfer matrix 290 compensates for electrode variations, such as transpiration of surface electrodes (e.g., from polarization of current) and/or oxidation of electrodes (e.g., from blood reactants). In some embodiments, processing unit 250 stores one or more tissue parameter information 80 (e.g., for processing by algorithm 255).

In some embodiments, cardiac motion during systole can be determined by measuring impedance changes between internal electrodes (e.g., one or more internal electrodes) and surface electrodes (e.g., one or more surface electrodes). This measured impedance change may represent an actual change in the position, geometry, and/or other characteristics of the heart, and the measured impedance change may be used to monitor cardiac function (e.g., tissue contractility, ejection fraction) during a clinical procedure, such as monitoring left ventricular volume over time.

In some embodiments, the transfer matrix 290 is determined from information (e.g., electrical activity) recorded from patient P1, for example, during a transfer matrix 290 creation process as described below. Alternatively or additionally, as also described below, the transfer matrix 290 may be determined from information (e.g., electrical activity) recorded from a different patient, patient P2 (e.g., a different mammalian subject having similar physiological properties as patient P1).

In some embodiments, volume V_XMay include an intermediate volume V_I2And one or more drive positions (e.g., drive position 412 described below), intermediate volume V_I2Defined by the space within the convex hull of the set of points represented by record location 312; drive signals (e.g., drive signals 413, also described below) are transmitted from one or more drive locations while the transfer matrix 290 is determined. The transfer matrix 290 may be determined as follows. In some embodiments, the convex hull of the recording locations 312 surrounds each drive location 412, and the volume V_I2Defined only by the convex hull of the recorded locations 312. The transfer matrix 290 is primarily volume dependentProduct V_I2Tissue characteristics within. Volume V_XMay also include a volume V_I1External but volume V_I1Approximate volume V_P2. The transfer matrix 290 also depends (albeit less dependent) on the volume V_P2Tissue characteristics within. In some embodiments, a volume V may be defined for first patient P1 according to the description above_XP1And volume V of second patient P2_XP2Can approximate the volume V_XP1(e.g., approximately V)_XP1Size, shape, and physiological characteristics).

In some embodiments, volume V_XComprising an intermediate volume V_I2Intermediate volume V_I2Defined by the space between an arbitrary distribution of the set of points represented by the recording locations 312 and one or more drive locations 412 from which the drive signals 413 are emitted while determining the transfer matrix 290. The transfer matrix 290 may be determined as described herein. In some embodiments, an arbitrary distribution of recording locations 312 encompasses each drive location 412 and the volume V_I2Defined only by the distribution of the recording locations 312. The transfer matrix 290 depends primarily on the volume V_I2Tissue characteristics within. Volume V_XMay also be included in the volume V_I1External but close to volume V_I1Volume V of_P2. The transfer matrix 290 also depends (albeit less dependent) on the volume V_P2Tissue characteristics within. In some embodiments, a volume V may be defined for the first patient P1_XP1(e.g., as described above), and a volume V of a second patient P2_XP2Can approximate the volume V_XP1(e.g., approximately V)_XP1Size, shape, and/or physiological characteristics).

In some embodiments, the console 200 or other component of the system 10 includes an electronic assembly, such as the signal generator 400 shown, configured to deliver electrical energy (e.g., deliver a drive signal). In these embodiments, the system 10 also includes a set of one or more energy delivery transducers, i.e., drive electrodes 411, the drive electrodes 411 delivering drive signals 413 to tissue of the patient at one or more drive locations 412. The drive position 412 may comprise one external to the patient's position (e.g., on the patient's skin)Or more positions (such as drive position 412 as shown)_S) And/or one or more locations within the patient (e.g., under the patient's skin) (e.g., drive position 412 as shown)_i). The drive signals 413 emitted by the drive electrodes 411 may be used to determine and/or adjust (herein "determine" or "calculate") the transfer matrix 290 (e.g., as described below), to perform a positioning operation (e.g., as described below), to correct a positioning coordinate system (e.g., an impedance field for positioning one or more devices within a field), and/or to perform another function. The drive signal (e.g., drive signal 413) may include a signal selected from the group consisting of: continuous wave, impulse, pattern sequence, amplitude modulation signal, frequency modulation signal, chirp, and combinations thereof. In some embodiments, one or more drive signals (e.g., drive signal 413) are implemented based on electrical characteristics or other characteristics of the applicable tissue.

In some embodiments, system 10 includes one or more patient-insertable devices, such as device 100 as shown. Device 100 may include a catheter or other patient-insertable device, such as a device including drive electrodes 411 (shown in fig. 1).

In some embodiments, system 10 includes one or more patient-attachable garments or other patient-attachable components, such as garment 50 as shown, which may be used to position one or more sensors of system 10 at one or more locations associated with patient P1, such as to position recording electrodes 311 relative to the patient. Recording electrodes 311 may be positioned on garment 50 and/or within garment 50.

In some embodiments, system 10 is configured to generate, receive, and/or process information using two or more modalities (e.g., drive signals and/or received signal modalities), such as: electrical potential and ultrasound, electrical potential and impedance (e.g., complex impedance such as dielectric properties), and/or other combinations of modalities (e.g., combinations of drive signals and/or received signal forms). One or more transfer matrices of the inventive concept may then be generated and subsequently used (e.g., in conjunction with the use of two or more transfer matrices) to distinguish local, and/or global differences (e.g., temporal and/or spatial differences) measured via a subset of each modality employed (e.g., insensitive versus sensitive measurements). For example, spatial or temporal variations in breathing pattern and/or breathing volume may be sensitive to both impedance and ultrasound modalities and less sensitive to cardiac potential modalities, while spatial and/or temporal variations in tissue conductivity will be sensitively measured via impedance, while measurements using ultrasound are less sensitive.

System 10 may include one or more sensors (e.g., electrodes configured to record electrical activity as defined herein) positioned on and/or under the skin of a patient. The system 10 may also include one or more energy delivery elements (e.g., electrodes configured to deliver electrical signals as defined herein) positioned on and/or under the skin of the patient. In some embodiments, the system 10 includes a vest or other garment (garment 50) that positions one or more sensors, transducers, and/or other functional elements relative to the patient's anatomy. For example, functional elements positioned in garment 50 may be used to perform one or more diagnostics and/or one or more therapeutic operations on a patient. In some embodiments, garment 50 includes one or more sensors configured to record patient physiological data used to generate diagnostic information selected from the group consisting of: ECG and other electrocardiographic information, blood pressure measurements, blood flow measurements, respiration measurements, heart sound measurements, p0₂Measurement results, pCO₂Measurements, ejection fraction measurements, organ function measurements, brain activity measurements, seizure activity measurements, and combinations of these. In some embodiments, system 10 also includes one or more sensors positioned under the skin of the patient (e.g., proximate to the heart, brain, and/or other organs), where data from the skin contact sensors and internal sensors is processed (e.g., by algorithm 255) to produce a diagnostic output. In some embodiments, for example, when Eintet Hoffing triangle is used as a seatWhen labeled, the system 10 creates a coordinate system to identify the patient's anatomical location. In some embodiments, system 10 creates a coordinate system based on the location of one or more surface electrodes (e.g., based on the location of garment 50 including one or more surface electrodes).

In some embodiments, the coordinate system is based on the location of one or more internal electrodes (e.g., based on the coordinate system of one or more drive electrodes positioned within the heart). In these embodiments, the coordinate system may be configured relative to the drive electrodes used as a coordinate reference or origin. Alternatively or additionally, the coordinate system may be configured relative to one or more surface electrodes serving as a coordinate reference (e.g., origin). Alternatively or additionally, the coordinate system may be configured with respect to an anatomical location (e.g., structure or boundary) that serves as a coordinate reference (e.g., origin).

In some embodiments, system 10 includes one or more sensors (e.g., electrodes 311) on the skin of the patient_S、321_S、411_SAnd/or electrode-based functional elements 99_S) And one or more sensors (e.g., electrodes 311) positioned in the patient's heart_I、321_I、411_IAnd/or electrode-based functional elements 99_I). In these embodiments, the sensors (e.g., electrodes) positioned in the patient's heart may include at least one sensor on the endocardial surface of the heart chamber (e.g., a contact electrode on the endocardial surface of the left atrium), and at least one sensor positioned in a chamber that is offset from the endocardial wall (e.g., a non-contact electrode in the left atrium or other chambers in flowing blood that is offset from all endocardial surfaces). The patient information 95 may be determined based on signals (data) received from one or more of the at least one skin surface sensor, the at least one endocardial surface contact sensor, and/or the at least one non-contact sensor.

The electrodes and/or other sensors of system 10 may include various shapes, surface areas, and materials of construction. In some embodiments, one or more skin contact electrodes (e.g., electrodes 311) for recording electrical activity and/or delivering electrical energy_S、321_S、411_SAnd/or electrode-based functional elements 99_S) Comprising one or more materials selected from: platinum-iridium, gold, carbon, polymers (e.g., polymer coatings), and combinations thereof. In some embodiments, one or more electrodes (e.g., electrode 311) positioned under the skin of the patient to record electrical activity and/or deliver electrical energy_I、321_I、411_IAnd/or electrode-based functional elements 99_I) Comprising one or more materials selected from: platinum-iridium, gold, carbon, polymers (e.g., polymer coatings), copper, silver-silver chloride, conductive gels, and combinations of these.

In some embodiments, electrodes and/or other sensors of system 10 (e.g., electrode 311)_S、321_S、411_SAnd/or electrode-based functional elements 99_S) Is positioned on the skin of the patient in a vertical arrangement, a horizontal arrangement, a diagonal arrangement, and/or a helical arrangement relative to the patient. For example, the sensors may be positioned and in these and/or other geometric arrangements via the garment 50 (e.g., via fixed attachments to the garment 50 and/or via pockets of the garment 50 receiving the sensors).

The console 200 may include one or more discrete components, such as when the console 200 includes one or more housings that collectively enclose the components of the processing unit 250, the user interface 260, the recording assembly 300, and/or the signal generator 400. Console 200 may include a number of discrete components (e.g., each component including a discrete housing) that communicate information, signals, and/or power between the components via wired and/or wireless connections. The console 200 may include components configured to be transported from one room to another (e.g., between a hospital's warehouse and a clinical operations room).

Processing unit 250 may include one or more components that receive, store, analyze, and/or otherwise process information (e.g., information recorded by recording component 300). Processing unit 250 may include one or more components that generate and/or otherwise provide information (such as information provided to signal generator 400) and are used by signal generator 400 to generate drive signals (e.g., drive signal 413 for driving electrode 411). Processing unit 250 may include one or more central processing units, such as CPU251 as shown. Processing unit 250 may include one or more electronic memory modules, such as memory 252 as shown.

CPU251 may include one or more Digital Signal Processors (DSPs) that may analyze signals received from one or more electrodes or other sensors of system 10 for calculating patient information (e.g., patient electrical information, patient motion, etc.), as described herein.

Console 200 may include a user interface, such as user interface 260 as shown, that may receive information and/or provide information to a user of system 10 (e.g., a clinician of patient P1 and/or P2 as described herein). The user interface 260 may include one or more user input components, such as input components selected from: a keyboard, a mouse, a touch screen, a joystick, a haptic controller, a microphone, switches, keys, and combinations of these. The user interface 260 may include one or more user output components, such as output components selected from: a display (e.g., a video monitor), a speaker, a tactile transducer, and combinations of these.

The transfer matrix 290 may include characteristics of electrical properties of tissue (e.g., bone, fat, skin, lung, blood, and/or connective tissue) between the first set of recording locations (e.g., the first set of recording locations 312) and the set of target locations (e.g., the set of target locations 90).

Based on the data at one or more recorded locations 312 (e.g., one or more patient skin locations 312)_SAnd/or one or more in-patient locations, internal locations 312_i) From the recorded information, the transfer matrix 290 of the system 10 may be used to calculate one or more patient positions 90 (e.g., one or more patient skin positions 90)_SAnd/or one or more in-patient locations, internal locations 90_i) Patient information of (c).

The transfer matrix 290 represents a matrix in which a series of measurements at a first location (e.g., a set of first locations) may be correlated with a feature at a second location (e.g., a set of second locations) determined by applying the transfer matrix to the series of measurements at the first location. The transfer matrix 290 may be generated by delivering drive signals (e.g., from an area proximate to the second location or otherwise) and by performing recording at the first location. Multiple recordings may be performed at one or more similar or dissimilar anatomical locations to create the transfer matrix 290.

The transfer matrix 290 represents the mathematical correspondence between measurements made in two separate domains. For example, two separate domains may include: a first domain within the patient's body and a second domain outside the patient's body, a first domain on a particular region of the patient's body and a second domain on another region of the patient's body, a first domain inside an organ within the patient's body and a second domain outside an organ within the patient's body, and/or combinations of these. The transfer matrix 290 mathematically describes the relationship between measurements made in the first domain and features (e.g., tissue features and/or electrical conditions) in the corresponding second domain. Such a transfer matrix 290 may also describe the relationship between measurements made in the second domain and the characteristics of the first domain. The application of the transfer matrix 290 may be used to computationally consider the feature differences between the two domains (both static and dynamic as imposed by physiology and environment as described above), and the application of the transfer matrix 290 enables the combined use of measurements from the two domains.

In some embodiments, a known electrical signal (potential or current) is emitted from a first drive electrode (e.g., an inner electrode) and recorded by one or more (e.g., all) recording electrodes (e.g., surface electrodes). Subsequently, a known signal is emitted from the second drive electrode (e.g., the inner electrode), and the known signal is recorded by one or more (e.g., all) of the recording electrodes (e.g., the surface electrodes). In some embodiments, a known signal is then emitted from the third, fourth, etc. drive electrodes (e.g., until all drive electrodes have been used). This embodiment provides a set of drive signals (voltage or current) from all drive electrodes (e.g., all internal electrodes) for each recording electrode (e.g., each surface electrode). In these embodiments, intrinsic cardiac signals (e.g., atrial electrograms) may be recorded using the same recording electrodes (e.g., body surface electrodes).

As described herein, the relationship (e.g., ratio) of the drive signal to the recorded second signal is used as a basis for the transfer matrix 290 and may be used to determine the calculated patient information 95. The transfer matrix 290 may be continuously updated (e.g., between measurements taken to produce calculated patient information 95), for example, to account for changes in: body fluid status, electrolyte concentration, skin resistance, and/or electrode location (e.g., recording electrode location).

In some embodiments, such as described below with reference to fig. 3, the system 10 is configured to create the transfer matrix 290. For example, the system 10 may include one or more electrodes or other transducers configured to deliver electrical energy (e.g., deliver drive signals), such as the drive electrodes 411 as shown. The drive electrodes 411 may be positioned at various drive locations 412 from which drive signals 413 are emitted. The system 10 may include a set of recording electrodes 321, the set of recording electrodes 321 may be positioned at a plurality of recording locations 322, and create a set of recording signals 323. In fig. 1, recording location 322 is the same as recording location 312 described above (e.g., when recording electrodes 311 and 321 are a same set of electrodes or at least one is a subset of the other, such as when patients P1 and P2 are the same patient, such as when electrode 311 is used to determine both transfer matrix 290 and calculated patient information 95). In other embodiments, the recording location 322 and the recording location 312 comprise different locations (e.g., all locations are different or at least one location is different), such as when the location 322 comprises locations on different mammalian subjects (e.g., for creating the universal transfer matrix 290) or the location 322 comprises different locations on the same patient.

The transfer matrix 290 may be determined by comparing (e.g., by an algorithm 255) the set of recorded signals 323 with the set of drive signals 413 emitted from the drive locations 412. In some embodiments, the drive position 412 comprises a position within the patient and the record position 322 comprises a position on the surface (skin) of the patient. Alternatively or additionally, the drive position 412 may comprise a position on the surface of the patient and/or the record position 322 comprises a position within the patient. In some embodiments, at least one of the drive position 412 and/or the recording position 322 includes both locations on the surface of the patient and within the patient. In some embodiments, at least one of the drive position 412 and/or the recording position 322 is limited to (i.e., limited to only including) a position on the surface of the patient. In some embodiments, at least one of the drive position 412 and/or the recording position 322 is limited to a position within the patient (i.e., is limited to only include a position within the patient).

When drive signals 413 are used to determine transfer matrix 290, drive electrodes 411 may include at least 1 electrode, at least 2 electrodes, and/or at least 48 electrodes, and recording electrodes 321 may include at least 4 electrodes, at least 10 electrodes, and/or at least 200 electrodes. In some embodiments, the drive electrodes 411 may be positioned at drive positions 412 that are at least 1mm apart from each other (such as at least 2mm apart, and/or at least 4mm apart, and/or at least 10mm apart), and the recording electrodes 321 may be positioned at recording positions 322 that are at least 2mm apart from each other (such as at least 3mm apart, at least 10mm apart, and/or at least 20mm apart).

In some embodiments, the drive position 412 includes one or more positions within the patient, such as a drive position selected from: within a chamber of the heart, on an endocardial surface of a heart chamber, on an epicardial surface of the heart, in a blood vessel of the heart (e.g., a vein or artery), in a pericardial cavity, in the esophagus, in and/or near the brain, in a blood vessel of the brain (e.g., a vein or artery), and combinations thereof. In these embodiments, device 100 may include one or more drive electrodes 411 (e.g., on a distal expandable basket or other distal portion of device 100), such as when the distal portion of device 100 is inserted into a patient's heart, resulting in the positioning of drive electrodes 411 on the endocardial surface of and/or within the heart cavity. In these embodiments, the associated set of record locations 322 may include locations within the patient, on the patient's skin, or both. The recording electrodes 321 may be positioned at one or more recording locations 322 selected from: chest, back, torso, shoulders, abdomen, thorax, head, and combinations of these. In some embodiments, system 10 includes at least 6 recording electrodes.

In some embodiments, the recording electrodes 321 include surface electrodes 321s, the surface electrodes 321s being positioned to cover a region surrounding the heart in all three dimensions (e.g., anterior-posterior, head-posterior, and right-to-left). In some embodiments, the surface electrode 321_SConfigured to deliver signals or other energy to perform positioning, electrical cardioversion, etc. (e.g., to avoid positional conflicts with individual electrodes used to perform those additional functions).

Alternatively or additionally, the drive signals 413 used to determine the transfer matrix 290 may be delivered from one or more drive locations 412 on the patient's skin, such as one or more drive locations selected from: chest, back, torso, shoulders, abdomen, thorax, head, and combinations of these. In these embodiments, the associated set of record locations 322 may include locations within the patient, on the patient's skin, or both within and on the patient's skin. The recording electrode 321 may be positioned at one or more recording locations 322 selected from: within a chamber of the heart, on an endocardial surface of a heart chamber, on an epicardial surface of the heart, in a blood vessel of the heart (e.g., a vein or artery), in a pericardial cavity, in the esophagus, in and/or near the brain, in a blood vessel of the brain (e.g., a vein or artery), and combinations of these.

In some embodiments, at least 4 surface electrodes are used to cover a 3-dimensional volume (e.g., to substantially provide drive signals to and/or record signals from the 3-dimensional volume). For example, a set of surface electrodes may include: 4 surface electrodes, the 4 surface electrodes positioned to form a tetrahedron that transects the body; 5 surface electrodes, of which 4 form a tetrahedron, the fifth surface electrode serving as a discriminating electrode non-coplanar with any tetrahedral surface; 6 surface electrodes forming 3 orthogonal or approximately orthogonal cartesian coordinate axes; 6 surface electrodes, of which 3 form a triangle on one side of the body and the other 3 form an inverted triangle on the other side of the body (e.g., chest and back).

In some embodiments, transfer matrix 290 is determined by one or more drive electrodes 411a delivering drive signals 413a comprising a first frequency and one or more drive electrodes 411b delivering drive signals 413b comprising a second, different frequency. In these embodiments, drive signals 413a and 413b may be delivered simultaneously (e.g., correspondingly received simultaneously by recording electrodes 321).

In some embodiments, transfer matrix 290 is determined by one or more drive electrodes 411a delivering drive signals 413a comprising a first frequency and one or more drive electrodes 411b delivering drive signals 413b comprising a similar or different second frequency. In these embodiments, the drive signals 413a and 413b may be delivered sequentially (e.g., received sequentially by the recording electrodes 321, respectively).

In some embodiments, the transfer matrix 290 is determined by evaluating the amplitude and/or phase of a set of recording signals 323 (e.g., recorded by recording electrodes 321 positioned at recording locations 322). For example, the transfer matrix 290 may include a numerical scaling factor based on a comparison of the amplitude and/or phase of the set of recording signals 323 with the amplitude and/or phase, respectively, of a set of drive signals 413 (e.g., delivered by drive electrodes 411 positioned at the drive locations 412). In some embodiments, the comparison is based on both the amplitude and phase of each set of signals.

In some embodiments, the emission of the drive signal 413 and the associated recording of the recording signal 323 occur over at least one physiological cycle of the patient, and the resulting transfer matrix 290 comprises a time-dependent (e.g., cycle time-dependent) transfer matrix. The associated physiological cycle may include a cardiac cycle (e.g., a cycle including systole and diastole), a respiratory cycle, a pressure change cycle (e.g., a periodically changing blood pressure), and/or other repeating physiological cycles of the patient. The recording may be performed over a plurality of cycles (e.g., at least 2 cycles, at least 3 cycles, or at least 5 cycles). The transfer matrix 290 may include one or more parameters that adapt proportionally over time. The transfer matrix 290 may include information related to changes within the physiological cycle, such as when the transfer matrix 290 includes a time-dependent transfer matrix that includes one or more components that change relatively consistently with signals recorded by the electrodes 311, such as to correlate these recordings made by the electrodes 311 within similar physiological cycles (e.g., compensation performed when calculating the patient information 95 and compensating for changes within the physiological cycle). In some embodiments, algorithm 255 may be configured to compensate for: a cardiac cycle (e.g., to compensate for cardiac motion), a respiratory cycle (e.g., to compensate for lung motion and/or other patient respiratory parameters), or both a cardiac cycle and a respiratory cycle. In some embodiments, the algorithm 255 calculates the patient information 90 by aligning the time-dependent transfer matrix 290 with the physiological cycle of the patient. The parameters of the transfer matrix 290 may vary according to a function and/or biological process, such as a cyclically and/or spatially varying process (e.g., blood flow or other cyclically varying cardiovascular process). In some embodiments, one or more parameters of the transfer matrix 290 may vary in time, linearly, and/or exponentially. These parameters may include values that are expanding and/or drifting. The variation over time and/or across space need not be completely periodic. These acyclic changes may also be modeled, for example, via a learning algorithm to create a model and train the model to compensate for the changes. Variations can also be compensated for by extrapolation from previous variation data (e.g., data recorded in patient P1 or a different mammal such as patient P2), such as data configured and used as a comparative model.

In some embodiments, the signals recorded during a respiratory cycle (e.g., at a frequency of 10-15 breaths/minute) and/or the signals recorded during a cardiac cycle (e.g., changes due to blood movement and/or contraction movement of the heart and the heart wall and electrodes) are averaged (e.g., at a frequency corresponding to the heart rate) to create a transfer matrix 290 (e.g., averaging results in a more stable transfer matrix 290, such as a transfer matrix 290 with improved stability over one or more respiratory and/or cardiac cycles).

In some embodiments, system 10 considers one or more physiological and/or anatomical parameters of a patient (e.g., patient P1 and/or patient P2), such as parameters selected from: rotation of the heart (e.g., toward the right or left side of the patient), the circumference of the chest cavity relative to the heart, the position of the heart in the chest cavity (e.g., a low weight patient having a relatively high positioned diaphragm, emphysema, and a COPD patient having a relatively low positioned diaphragm), and combinations of these. These parameters may be determined by analyzing geometric characteristics of the patient, such as the circumference (which may be calculated based on the distance between the surface electrodes, as examples, where impedance-based measurements may be used to determine the distance), the number and angle between the surface electrodes around the body, and/or the rotation and/or position of the heart relative to the surface electrodes. For example, the standardized location of surface electrodes (e.g., electrodes used to provide an ECG recording) may be used as a reference, and diagnostic bioelectric signals measured from the surface electrodes may be used to assess the physiological and/or anatomical condition of the patient. By way of example, on a standard 12-lead ECG, the presence of certain signal features in lead V1 or V2 may indicate a rightward deviation in heart position. Alternatively, a signal characteristic in V4-5 may indicate a leftward deviation in heart position, while other signal characteristics may indicate a higher or lower heart position.

In some embodiments, the system 10 modifies the transfer matrix 290 at least once, such as at least once during a single operation on a single patient. For example, the system 10 may modify the transfer matrix 290 intermittently over time and/or relatively continuously ("continuously" herein), such as in a closed-loop manner. The modification performed by the system 10 may be based on at least one patient parameter that varies over time. In some embodiments, the modification performed by the system 10 may be based on at least two or at least three patient parameters that vary over time. The modification performed by the system 10 may be based on one or more patient parameters that vary periodically over time, such as parameters that vary in relation to the respiratory cycle and/or cardiac cycle of the patient. The patient parameter may vary linearly and/or exponentially. In these embodiments, the system 10 may include one or more sensors (e.g., electrodes 311, 321, and/or 411, and/or functional elements 99 described below) configured to generate signals related to patient parameters used to adjust the changes in the delivery matrix 290. The monitoring may be performed continuously (e.g., when the transfer matrix 290 is continuously modified) and/or intermittently (e.g., when the transfer matrix 290 is intermittently modified).

In some embodiments, the transfer matrix 290 for patient P1 (e.g., determining patient information 95 based on recorded signals 313) contains or at least includes information incorporated from previously calculated (e.g., from at least one other mammalian subject (e.g., patient P2)) and/or other normalized transfer matrices (normalized transfer matrix 290'). As used herein, the delivery matrix 290 may comprise a standardized delivery matrix 290' (e.g., based on one or more individual mammals (patient P2)). The transfer matrix 290 may include a transfer matrix based only on data from patient P2, only on data from patient P1, or a transfer matrix based on data from patient P2 and data from patient P1. In some embodiments, the normalized transfer matrix 290 '(or a portion thereof) may be selected based on characteristics of the patient (characteristics of patient P1) for which the normalized transfer matrix 290' (or a portion thereof) is to be used. For example, a plurality of different normalized transfer matrices 290' may be determined, each based on one or more mammalian subjects (e.g., patient P2) having one or more particular patient characteristics (e.g., one or more similar patient parameter levels). In some embodiments, a single standardized delivery matrix 290 'may accommodate various patient characteristics, such as when the standardized delivery matrix 290' is customized based on one or more particular patient characteristics. Method and apparatus for creating a standardized transfer matrix290 'of similar subject patient P1, the standardized delivery matrix 290' may be selected and/or customized to be used as the delivery matrix 290. In some embodiments, applicable patient parameters for selection and/or customization include parameters selected from the group consisting of: gender, weight, height, body or body part size, Body Mass Index (BMI), (e.g., determined by a functional element 99 including an imaging device such as a CT scanner or MRI) chest circumference, location of esophagus, size of atrium, filling of atrium volume, atrial pressure, ratio of fat to water, ratio of air to water to fat, bone location (e.g., determined by MRI), drugs administered, drug level, electrolyte level, pH, pO₂、pCO₂Weight of water, and combinations thereof.

In some embodiments, the transfer matrix 290 includes a standardized transfer matrix 290 '(e.g., based on one or more mammals other than patient P1 (patient P2)), where differences in the positions of recording electrodes on patient P2 used to create the standardized transfer matrix 290' and the positions of recording electrodes on patient P1 used to generate the calculated patient information 95 are considered by the system 10.

In some embodiments, the normalized transfer matrix 290' may be derived by analyzing the collection of data sets from multiple (i.e., two or more) patients P2. In some embodiments, the data set includes measured information from each individual patient P2, such as location information (e.g., locations of anatomical structures and/or sensors and other objects), tissue information (e.g., tissue characteristics, and/or qualitative categories), information related to the physiological process (e.g., respiration and/or cardiac motion, and the respiration and/or cardiac motion may include recordings from the sensors over a period of time and/or data calculated from these recordings), environmental information (e.g., background electrical noise or device interconnections), and/or cardiac information (e.g., electrical activation times, conduction patterns, surface charges, dipole densities, (measured as voltages) cardiac potential electrograms, etc.). In some embodiments, the data set includes a transfer matrix 290 calculated from measurements in each individual patient P2 and image data (e.g., CT and/or MRI data) from each individual patient P2. Memory 252 may be used to store a collection of data sets from a plurality of patients P2. The collection of data sets from multiple patients may include different populations of P2 patients with different characteristics (e.g., gender, size, presence of disease such as emphysema, age, heart location) that may also be included in the patient data sets.

Analysis of the collection of data sets from multiple patients P2 may be performed to identify patterns, correlations, correspondences, and/or other similar relationships between data set elements, such as measured information, measured transfer matrices 290, changing patient characteristics, and/or the entire collected image data. Such analysis of the collection of data sets may be a "training" or "learning" step in the course of a computation and/or algorithm (e.g., machine learning method). The analysis produces one or more quantitative entities (e.g., a system of equations or a computational "model") that describe complex relationships between data set elements throughout a population of patients P2. In some embodiments, for example: and (4) performing analysis by calculation methods such as classification, collaborative filtering, regression, clustering and/or dimension reduction. The quantitative entity may be applied in a second step, where one or more dataset elements from patient P1 are provided as input and then used to calculate, select, customize, optimize, update and/or predict the normalized transfer matrix 290' for patient P1. In some embodiments, the dataset elements from patient P1 are only a subset of the dataset elements used to calculate the quantitative entity, thereby reducing or eliminating the acquisition or measurement step for patient P1.

In some embodiments, the normalized transfer matrix 290' calculated, selected, customized, optimized, updated, and/or predicted for patient P1 has increased accuracy or reduced artifacts compared to the transfer matrix measured directly in P1 due to potential defects or limitations of the measurement (e.g., environmental interference or human error). In some embodiments, the data set elements from patient P1 may be provided once to produce a single normalized transfer matrix 290 ', and/or the data set elements from patient P1 may be provided multiple times in succession (e.g., in an interval or continuous manner), such as to produce multiple normalized transfer matrices 290' that are applied in succession, in order to provide dynamic updates of the time-varying relationships. In some embodiments, the data set elements used to generate the quantitative entities may contain time-varying information, and the data set elements from patient P1 need only be applied once or a limited number of times in order to generate the plurality of normalized transfer matrices 290 'to provide dynamic updates more frequently than the information from P1, thereby providing greater time resolution in updating the normalized transfer matrices 290'. In these embodiments, the system 10 may use a normalized transfer matrix 290 '(e.g., the transfer matrix 290 includes only the normalized transfer matrix 290') to generate the calculated patient information 95. In some embodiments, for example, if an appropriate standardized transfer matrix 290' can be selected and/or customized based on characteristics of patient P1 (e.g., characteristics such as size, weight, circumference, and/or rotation and/or position of the heart), patient images (e.g., MRI or CT scans) are not used (e.g., not required).

In some embodiments, the system 10 utilizes dynamic feedback and/or machine learning to determine the transfer matrix 290 and/or uses the transfer matrix 290 to determine the calculated patient information 95 based on the recorded signals 313. In some embodiments, the collection of data sets from one or more patients P2 (e.g., to create standardized delivery matrix 290') may include treatment information. For example, the normalized delivery matrix 290' may be based on one, two, or more treatment parameters selected from: duration (e.g., duration of energy delivery), intensity (e.g., intensity of energy delivery), amplitude (e.g., amplitude of energy delivery), temperature (e.g., temperature of tissue receiving energy), power (e.g., power of energy delivery), impedance (e.g., impedance of tissue), and combinations of these. Each parameter may be analyzed in absolute, relative, and/or differential form. The normalized delivery matrix 290' may be based on tissue parameters related to the applied therapy (e.g., tissue parameter information 80 stored by the system 10), such as one, two, or more tissue parameters selected from the following (e.g., parameters of tissue receiving ablation energy and/or other therapy): size, depth, thickness, density, composition, and combinations of these. The normalized transfer matrix 290' may be based on the effectiveness of the treatment (e.g., ablation treatment) on the local and/or regional electrical properties of the tissue. The normalized delivery matrix 290' may be based on the acute (i.e., short-term) effectiveness and/or the chronic (e.g., long-term) effectiveness of the treatment. Suitable short-term and/or long-term treatment effectiveness parameters include, but are not limited to: cancelling conduction, a change in conduction, velocity, amplitude and/or direction of an electrical signal in tissue, a change in measured amplitude, frequency and/or rate of an electrical signal, a change in rate, pattern and/or frequency of a cardiac cycle, a transition in heart rhythm, a change in duty cycle and/or duration of intermittent cadence, maintenance of a desired heart rhythm, transition to an alternate cadence (e.g., a desired or undesired cadence), and/or a duty cycle of a resulting cadence (e.g., a desired or undesired cadence). The normalized transfer matrix 290' may be based on short-term and/or long-term treatment effectiveness parameters related to changes in local, regional, and/or global mechanical and/or functional properties of the tissue, such as parameters related to: changes or maintenance of cardiac output and function; and/or changes in tissue stiffness, contractility, displacement, and/or strain. As described above, the analysis of the collection of data sets from one or more patients P2 may be performed by system 10 (e.g., via algorithm 255), and the results used to provide calculated patient information 95 to calculate, select, customize, predict, update, and/or otherwise enhance therapy (e.g., therapeutic energy delivery and/or drug therapy strategies) for patient P1. In some embodiments, the transfer matrix 290 is based on a reduced data set (a subset of a complete data set) recorded according to patient P1, which is used in conjunction with data (e.g., a full set) recorded according to one or more patients P2. In these embodiments, enhancements in treatment are achieved without the need to acquire or otherwise measure the remaining data set from the P1 patient, thereby reducing cost, time, and/or complexity of operation. For example, based on the included patient P2 data, the assessment of one or more lesions created during a treatment procedure may be eliminated or at least reduced.

In some embodiments, system 10 utilizes machine learning such as described above. The system 10 may be configured to obtain sequential measurements from one or more (e.g., all) surface electrodes configured to record signals sequentially emitted from each of one or more internal electrodes and track changes over time (e.g., physiological changes related to signal changes). The system 10 may evaluate the respiratory and/or cardiac cycles, and the system 10 may perform compensation (e.g., subtraction and/or cancellation) to reduce the undesirable effects of these changes (e.g., as described above). The system 10 can determine cardiac motion throughout the cardiac cycle by evaluating impedance changes between the inner and surface electrodes. The cardiac motion determination may be used to calculate mechanical, dynamic, and/or other functional characteristics of the heart, such as contractility, volume change over time, ejection fraction, wall motion, wall displacement, strain, and/or pressure, and may be used to monitor cardiac function during clinical procedures (e.g., to assess the safety of the procedure). In some embodiments, the function of the ventricles may be measured, for example, by measuring transthoracic impedance (e.g., in combination with signals provided and/or recorded by the internal electrodes). Atrial and ventricular functions may be separated by a time window: cardiac contraction occurs when ventricular function is assessed, for example, 200ms to 500ms after QRS compounding. In some embodiments, the geometry (e.g., diameter, circumference, volume, etc.) of the chest is determined based on measurements made by two or more surface electrodes and changes in geometry relative to breathing (e.g., changes related to breathing excursion and/or breathing frequency). In some embodiments, during respiration and cardiac contraction, the position of the heart relative to surface electrodes (e.g., 12 lead ECG positioned on the skin, electrodes 311, 321, and/or 411) is measured, as well as the rotation, position, and/or displacement (e.g., up and down) of the heart. The heart motion during systole can be determined in different heart rhythms (e.g., sinus rhythm, flutter, and/or fibrillation). The system 10 may integrate anatomical structure information (e.g., from CT, MRI, ultrasound, and/or other imaging devices) along with other information (e.g., ECG information and/or signal axes of body surface electrodes) into a delivery matrix 290 (e.g., information related to air/fat/water ratio; location of bones, spine, and/or ribs; size of chest diameter; and/or angle and/or rotation of the heart). The system 10 may be configured to create the transfer matrix 290, and the system 10 may also be configured to update (e.g., adapt or otherwise modify) the transfer matrix 290 (e.g., continuously or at least repeatedly update the transfer matrix 290). The system 10 may be configured to perform positioning operations, such as to determine the position of one or more electrodes (e.g., internal drive and/or internal recording electrodes) relative to a positioning coordinate system.

In some embodiments, system 10 is configured to vector pulses of energy from one or more electrodes positioned on the skin of the patient (e.g., electrode 311)_S、321_S、411_SAnd/or electrode-based functional elements 99_SOne or more of) to one or more electrodes (e.g., electrode 311) positioned within the patient's body_I、321_I、411_IAnd/or electrode-based functional elements 99_IOne or more of) such as one or more electrodes integrated onto a distal portion of the device 100. In these embodiments, recording may be initiated by one or more skin electrodes (and/or individual skin electrodes may record) immediately after delivery of the vector pulse, such as to determine a characteristic of the tissue based on the recording, such as to determine electrical conduction characteristics and/or physical characteristics (e.g., scar, fibrosis, fiber orientation, etc.) based on the response of the tissue to the vector pulse. Electrical activation of tissue may be detected immediately in the tissue region surrounding the intracardiac catheter. This approach is similar to CRT devices that use electric vectors to activate tissue from a housing (e.g., an implantable metal housing) to a lead. Amplitude and phase information may also be acquired to determine whether the pulse activates a tissue region in the direction of the vector. This determination may be performed for a subset of surface electrodes of the intracardiac electrodes to determine whether the tissue is viable in the vector direction. The vector is rotated around the patient's body and/or modulated by creating vectors using different subsets of surface electrodes of the intracardiac catheter electrodes to create a 3D map of the viability of the tissue. Alternatively or additionally, the system 10 mayA vector pulse configured to deliver energy between the surface electrodes.

The recording assembly 300 may be integrated into the console 200 and/or the recording assembly 300 may include a second, separate console operatively attached to the console 200.

Recording component 300 may be configured to record signals of one or more electrodes or other sensors of system 10, such as recording electrode 311. Recording assembly 300 may record signals from one or more other electrodes of system 10, such as an electrode also configured as a drive electrode that: drive electrodes 411, for example comprising one or more drive electrodes on the skin of a patient_SAnd/or a drive electrode 411 including one or more electrodes positioned within the patient (e.g., when included on the patient-inserted device 100)_I. The recording assembly 300 may be connected to one or more electrodes via wired or wireless connections as shown in FIG. 1 (connections to the recording electrodes 311 and 321 shown via solid lines, and connections to the drive electrode 411 shown via dashed lines connected to solid lines).

The recording assembly 300 may include circuitry, such as a patient isolation circuit 301 as shown, the patient isolation circuit 301 configured to isolate a patient (e.g., patient P1 or P2 as shown) from undesired shocks or other undesired interactions with the recording assembly 300. Recording assembly 300 may include one or more analog-to-digital converters, shown as A2D 302, which may be configured to convert recorded analog signals to digital signals (e.g., digital signals received by processing unit 250 from recording assembly 300). Recording component 300 may include one or more signal filters, such as filter 303 as shown, which may be configured to filter out unwanted noise or other unwanted signals. The recording assembly 300 may include other signal recording and/or other signal processing circuitry known to those skilled in the art, such as a wireless receiver configured to receive wireless signals from the garment 50, a wireless transmit electrode of the system 10, and/or another wireless transmitter.

In some embodiments, recording component 300 is configured to multiplex (e.g., include multiplexing circuitry) the connections to the plurality of sensors such that a first set of one or more sensors (e.g., electrodes configured to record electrical activity) are recorded for a first period of time, after which a second set of one or more sensors (e.g., electrodes configured to record electrical activity) are recorded for a subsequent second period of time. In some embodiments, three or more sets of sensors are multiplexed.

As described above, the recording assembly 300 may be configured to perform dynamic impedance and/or dynamic voltage measurements related to changes in the patient's respiratory and/or physiological cycles.

The recording assembly 300 may be configured to record from multiple electrodes collectively (e.g., via multiplexing or other schemes) to form a "macro-electrode," e.g., to take advantage of electrical and/or geometric advantages of more than one electrode and/or more than one recording channel. Examples of some advantages include a larger effective electrode surface area (from multiple electrodes) and a lower input impedance (through multiple parallel recording channels).

Recording electrodes 311 may include one or more electrodes placed on the patient's skin (electrodes 311 as shown in the figure)_S) And/or one or more electrodes (shown as electrode 311) disposed within the patient's body_i). The recording electrode 311 may include two or more electrodes, for example, at least 2, at least 4, at least 6, or at least 10 electrodes.

In some embodiments, recording electrodes 311 include at least 3 electrodes (e.g., 3 electrodes included in the standard 6 limb leads used for ECG recording). In some embodiments, recording electrodes 311 include at least 9 electrodes (e.g., 9 electrodes included in a standard 12-lead ECG). In some embodiments, recording electrodes 311 include no more than 1000 electrodes (e.g., up to 1000 surface electrodes included in garment 50, such as at least 50 electrodes, at least 100 electrodes, and/or at least 250 electrodes positioned in garment 50). In some embodiments, recording electrodes 311 are positioned on the surface of the patient in a relatively uniform pattern (e.g., a uniform pattern provided by garment 50). For example, when at least 2 electrodes 311 (e.g., at least 2 surface electrodes) are used for each axis of the coordinate system used, the number of recording electrodes 311 may be determined by using the coordinate system used.

Recording electrodes 311 may include one, two, or more electrodes positioned on the patient's skin, for example at a location 312 selected from_STreating: chest, back, torso, shoulders, abdomen, skull, face, arms, legs, groin, and combinations of these. In these embodiments, the target location 90 may include one or more locations within the patient's body, such as one or more locations on and/or within the patient's organ. For example, the recording location 312 may include one or more locations selected from the group consisting of: chest, back, torso, shoulders and/or abdomen; the target location 90 may include one or more cardiac locations, such as cardiac locations selected from the group consisting of: epicardial surface of the heart, within the heart tissue (subendocardial), endocardial surface of the heart chamber, intracardial, pericardial cavity, pericardium, and combinations thereof. In some embodiments, recording electrodes 311 include at least one electrode positioned in each of the following locations: in the heart chamber, on the skin and in the esophagus. In some embodiments, recording electrode 311 includes one internal location and at least one non-intracardiac location (e.g., a location on the skin surface, a location on the epicardial surface, and/or a location on the pericardial surface). In some embodiments, the recording electrodes 311 include at least 9 or at least 12 recording electrodes 311 (e.g., 9 or 12 electrodes further configured as a 12-lead EKG device).

Recording electrode 311 may include one, two, or more electrodes that are positioned 312 via garment 50_SIs positioned on the skin of the patient. The garment 50 may be configured to position the recording electrodes 311 at various locations relative to each other and/or relative to the patient's anatomy.

Recording electrode 311 may include one, two, or more electrodes positioned within the patient, for example, at recording location 312 on and/or within the patient's organ_ITo (3). In some embodiments, the location 312 is recorded_IA cardiac location comprising a selection from: a location within a chamber of the heart, a location on an endocardial surface of the heart, a location on an epicardial surface of the heart, and combinations thereof. In some embodiments, the location 312 is recorded_IComprising one or more positions selected from: the esophagus, epicardium (e.g., accessed via a transthoracic or subxiphoid incision), pericardium (e.g., via a subxiphoid incision), proximate to but external to the heart, and combinations thereof. In some embodiments, the location 312 is recorded_IIncluding locations containing interstitial fluid (e.g., tissue surrounding the heart and/or subcutaneous tissue locations). In some embodiments, the location 312 is recorded_IIncluding a position within the spine and/or at least proximate to the spine and/or a position within the brain and/or at least proximate to the brain.

In some embodiments, recording electrodes 311 include at least one recording electrode positioned on the skin of the patient, and at least one recording electrode positioned within the patient. In these embodiments, externally placed (e.g., on the skin) recording electrodes 311 may be multiplexed_SAnd a recording electrode 311 placed internally (e.g., within the patient's body)_ITo provide a source (e.g., to provide functionality as a recording electrode) and/or a sink (e.g., to provide functionality as a drive electrode). Multiplexing of electrodes (e.g., recording electrodes 311) may be performed to form a group of electrodes that act as a single source and/or a single sink.

In some embodiments, the recording electrode 311 includes one, two, three, or more electrodes selected from: body surface electrodes, intracorporeal electrodes (e.g., electrodes placed in the body, under the patient's skin), percutaneous electrodes, subcutaneous electrodes, epicardial electrodes, pericardial electrodes, spinal electrodes, brain electrodes, and combinations of these.

In some embodiments, the recording electrode 311 includes one, two, three, or more electrodes selected from: one or more electrodes configured to transmit and/or receive a localization signal; a plurality of electrodes configured to generate an ECG signal, such as at least 9 electrodes of a 12-lead ECG device; a plurality of electrodes configured to generate a high density ECGi signal; one or more electrodes configured to deliver cardiac pacing energy; one or more electrodes configured to deliver defibrillation energy; one or more electrodes configured to deliver therapeutic energy; and combinations of these (e.g., to avoid the need for standard ECG patch electrodes, pacing components, and/or defibrillation components).

In some embodiments, recording electrodes 311 are configured to transmit and/or receive localization signals, such as localization signals for identifying the location of one or more devices (e.g., device 100 described herein) located within the patient. For example, signal generator 400 may provide a positioning signal received by recording electrode 311 to drive electrode 411. Additionally or alternatively, signal generator 400 may be electrically attached to recording electrode 311 (e.g., via a catheter represented by dashed lines), and signal generator 400 may provide a positioning signal (e.g., received by drive electrode 411, electrode 321, and/or other electrodes of system 10) to recording electrode 311.

In some embodiments, recording electrode 311 is positioned (relative to the patient) in a defined pattern (e.g., a standardized pattern), such as a pattern defined by a coordinate system. For example, one or more recording electrodes 311 may be positioned in the garment 50, and the garment 50 positioned relative to the patient to position the recording electrodes 311 in a particular pattern relative to the patient (e.g., a coordinate system may be normalized via the garment 50).

In some embodiments, recording electrode 311 includes one or more electrodes further configured to record an ECG signal of the patient, such as when recording electrode 311 includes: at least 9 electrodes of a 12 lead ECG device and/or a plurality of electrodes configured to generate a high density ECGi signal. Recording electrode 311 may be configured to provide arrhythmia monitoring of the patient. In these embodiments, the recording electrode 311 may be specifically positioned with respect to the patient's anatomy by the garment 50.

In some embodiments, recording electrode 311 is also configured to deliver pacing energy and/or defibrillation energy to the patient, such as that provided by signal generator 400. In these embodiments, the recording electrode 311 may be specifically positioned with respect to the patient's anatomy by the garment 50.

Recording electrodes 321 may include one or more electrodes placed on the patient's skin (electrodes 321 as shown in the figure)_S) And/or one or more electrodes (shown as electrodes 321) disposed within the patient's body_i). The recording electrodes 321 may include two or more electrodes, for example, at least 2, at least 4, or at least 10 electrodes. In some embodiments, recording electrodes 321 comprise at least twice the number of coordinate axes present in the coordinate system used by system 10, and/or recording electrodes 321 comprise a number of electrodes that is at least one more than the number of coordinate axes present in the coordinate system (e.g., 4 electrodes for a 3-axis coordinate system). In some embodiments, recording electrodes 321 include at least 9 electrodes (e.g., at least 9 electrodes further configured as a standard 12-lead ECG device). In some embodiments, recording electrodes 321 include at least 3 electrodes (e.g., 3 electrodes further configured as a standard 6 limb lead ECG).

Recording electrodes 321 may include one, two, or more electrodes positioned on the skin of the patient, for example at a location 322 selected from_STreating: chest, back, torso, shoulders, abdomen, skull, face, arms, legs, groin, and combinations of these. In some embodiments, the recording electrodes 321 include at least one electrode located in each of the following positions: a limb of the patient (e.g., on a leg or arm of the patient) and a torso of the patient (e.g., at least 2, 4, or 6 electrodes across the torso of the patient).

Recording electrode 321 may include one, two, or more electrodes at location 322 via garment 50_SIs positioned on the skin of the patient. The garment 50 may be configured to position the recording electrodes 321 at various locations relative to each other and/or relative to the patient's anatomy.

Recording electrodes 321 may include one, two, or more electrodes positioned within the patient, e.g., at recording locations 322 on and/or within the patient's organ_ITo (3). In some embodimentsMiddle, recording position 322_IA cardiac location comprising a selection from: a location within a chamber of the heart, a location on an endocardial surface of the heart, a location on an epicardial surface of the heart, and combinations thereof. In some embodiments, location 322 is recorded_IComprising one or more positions selected from: the esophagus, epicardium (e.g., accessed via a transthoracic or subxiphoid incision), pericardium (e.g., via a subxiphoid incision), proximate to but external to the heart, and combinations thereof. In some embodiments, location 322 is recorded_IIncluding locations containing interstitial fluid (e.g., tissue surrounding the heart and/or subcutaneous tissue locations). In some embodiments, location 322 is recorded_IIncluding a position within the spine and/or at least proximate to the spine and/or a position within the brain and/or at least proximate to the brain.

In some embodiments, recording electrodes 321 include at least one recording electrode positioned on the skin of the patient and at least one recording electrode positioned within the patient. In these embodiments, externally placed (e.g., on the skin) recording electrodes 321 may be multiplexed_SAnd a recording electrode 321 disposed internally (e.g., within the patient's body)_ITo provide a source (e.g., to provide functionality as a recording electrode) and/or a sink (e.g., to provide functionality as a drive electrode). Multiplexing of electrodes (e.g., recording electrodes 321) may be performed to form a group of electrodes that act as a single source and/or a single sink.

In some embodiments, recording electrodes 321 include one, two, three, or more electrodes selected from: body surface electrodes, body internal electrodes, percutaneous electrodes, subcutaneous electrodes, epicardial electrodes, pericardial electrodes, spinal electrodes, brain electrodes, and combinations of these.

Signal generator 400 may be electrically attached to recording electrode 321 (e.g., via a conduit represented by dashed lines), and signal generator 400 may provide a drive signal (e.g., drive signal 413) or other electrical energy (e.g., received by drive electrode 411, electrode 311, and/or other electrodes of system 10) to recording electrode 321.

In some embodiments, recording electrodes 321 are positioned (relative to the patient) in a defined pattern (e.g., a standardized pattern), such as a pattern defined by a coordinate system. For example, one or more recording electrodes 321 may be positioned in the garment 50, the garment 50 being positioned relative to the patient to position the recording electrodes 321 in a particular pattern relative to the patient (e.g., the coordinate system may be normalized via the garment 50).

Signal generator 400 may be integrated into console 200 and/or signal generator 400 may comprise a second, separate console operably attached to console 200.

Signal generator 400 is configured to generate a signal that is provided to one or more electrodes or other transducers of system 10 (e.g., drive electrode 411).

The signal generator 400 may include circuitry (shown as patient isolation circuitry 401) configured to isolate a patient (e.g., patient P1 or P2 as shown) from undesired shocks or from other undesired interactions with the signal generator 400. Signal generator 400 may include one or more digital-to-analog converters (e.g., D2A 402 as shown) that may be configured to convert digital signals (e.g., digital information received from processing unit 250) into analog signals. Signal generator 400 may include one or more signal filters (shown as filter 403) that may be configured to filter out unwanted noise or other unwanted signals. Signal generator 400 may include other signal generators and/or other signal processing circuits known to those skilled in the art.

In some embodiments, signal generator 400 is configured to provide a positioning signal, such as a positioning signal provided to drive electrode 411, recording electrode 311 (e.g., recording electrode 311 positioned in garment 50), and/or other electrodes of system 10.

In some embodiments, signal generator 400 is configured to provide energy to pace and/or defibrillate the patient's heart, such as pacing and/or defibrillation energy provided to recording electrode 311 (e.g., recording electrode 311 positioned in garment 50), drive electrode 411, functional element 99, and/or other electrodes of system 10.

In some embodiments, signal generator 400 is configured to multiplex (e.g., include multiplexing circuitry) the connections to the plurality of transducers such that a first set of one or more transducers (e.g., electrodes configured to deliver electrical signals and/or other electrical energy) are energized for a first time period, after which a second set of one or more transducers (e.g., electrodes configured to deliver electrical signals and/or other electrical energy) are energized for a subsequent second time period. In some embodiments, three or more sets of transducers are multiplexed. As described above, the drive electrodes may be configured (e.g., by multiplexing or another scheme) to be interconnected to form macro electrodes. The groupings of drive electrodes may be patterned to provide geometric and/or electrical advantages, such as shaping the source field in the body, maximizing linearity of the source field, maximizing field curvature of the source field, and/or maximizing or minimizing edge effects by creating or eliminating "holes" in the electrode sets.

In some embodiments, signal generator 400 is derived from a first set of electrodes (e.g., electrodes 411) positioned within the patient's body_I) The transmission is performed while recording assembly 300 simultaneously records signals from a second set of electrodes (e.g., electrodes 311) positioned on the patient's skin_S) Then signal generator 400 from a second set of electrodes (e.g., electrodes 311) positioned on the patient's skin_S) Transmitting while recording signals from a first set of electrodes (e.g., electrodes 411) in the patient's body_I) Of the signal of (1). Such alternating signal sources and receivers may last for multiple periods. In some embodiments, algorithm 255 is configured to determine the time of each portion of the cycle, and/or determine in which electrodes to deliver the signal and record the signal. The combination of multiplexing of signal source and receiver variations to implement the electrodes of system 10 allows flexibility in establishing, shaping, and/or modulating the geometric orientation and shape of the signal source and receiver signal paths (e.g., fields) through the body. The geometric orientation and shape of the signal paths through the body can be varied over time to produce a temporally and spatially varying sequence or pattern.

In some embodiments, at least one drive electrode 411 is positioned on the patient's skin (e.g., via garment 50) and potentially held in place by garment 50 (e.g., garment 50 includes one or more drive electrodes 411). In these embodiments, drive electrodes 411 may be configured to deliver drive signals 413 used to determine (as described herein) transfer matrix 290, deliver positioning signals, deliver cardiac pacing energy, deliver defibrillation energy, deliver therapeutic energy (e.g., deliver energy to inhibit seizures, headaches, or other neurological conditions, and/or otherwise treat adverse patient conditions), and/or perform another function.

The device 100 may include one or more devices configured to be inserted into a patient (e.g., into the vasculature of the patient and/or otherwise under the skin of the patient). In some embodiments, the apparatus 100 includes a distal portion configured to be inserted into a chamber of a heart of a patient P1. The device 100 may comprise a set of electrodes (drive electrodes 411) configured to provide a drive signal.

Device 100 may include a mapping and/or ablation device, such as an ablation device that is localized via localization signals provided by system 10 (e.g., localization signals delivered by recording electrodes 311).

The garment 50 may include one or more different forms that position one or more recording electrodes 311 at a location relative to the patient's anatomy (e.g., at a particular anatomical location on the patient's skin). Garment 50 may comprise a garment selected from the group consisting of: vests, shirts, belts, and combinations of these.

The garment 50 may include a wireless transmitter (e.g., a functional element 99 configured as a wireless transmitter)_S) Such as a wireless transmitter configured to wirelessly transmit recordings made by one or more electrodes and/or other sensors of the garment 50 to a receiving element of the recording assembly 300.

In some embodiments, system 10 utilizes one or more electrodes (e.g., one or more electrodes 311) of garment 50_S、321_S、411_SAnd/or electrode-based functional elements 99_S) To perform impedance tomography of the torso of the patient.

In some embodiments, the garment 50 is simply configured as a template, for example, when the garment 50 is placed on a patient to mark sensor placement locations, and/or when the garment 50 includes openings through which sensors are placed on the patient's skin (e.g., after the garment 50 is removed).

The calculated patient information 95 may include an electrical activity map of an organ (e.g., heart or brain) of the patient. The plotted electrical activity may include voltage information, dipole density information, and/or surface charge information. In cardiac applications, the target location 90 associated with the calculated patient information 95 may include a location on an endocardial surface, a location within cardiac tissue, and/or a location on an epicardial surface. In brain applications, the target location 90 associated with the calculated patient information 95 may include a location on the surface of the brain and/or within the brain (e.g., in the cerebral cortex and/or within deep brain).

The calculated patient information 95 may include information types selected from the group consisting of: electrical information (e.g., voltage information, surface charge information, tissue charge information, and/or dipole density information); tissue; structural or mechanical information (e.g., density, and/or difference in mechanical properties (e.g., density), size, and/or shape of the varying region of mechanical properties (e.g., density)); tissue composition information (e.g., damaged tissue, inflamed tissue, and/or denatured tissue, such as denatured protein, collagen, fibrosis, fat, and/or nerves); electrogram flow information; impedance information; phase information (e.g., for phase mapping), and combinations of these. For example, the calculated patient information 95 may include tissue density information that has been modified in a tissue ablation operation (e.g., an RF or other cardiac tissue ablation operation for treating cardiac arrhythmias), e.g., to assess the quality of the performed ablation. In some embodiments, the calculated patient information 95 may include a combination of electrical information (such as surface charge information) and mechanical and/or compositional properties of the tissue (density or presence of denatured proteins, or other indications of ablation lesions or other structural formations of the treated tissue) such that the effectiveness of the delivered treatment may be classified as complete or incomplete. For example, the electrical information collected by the system 10 may indicate a loss of electrical conduction while the structural formation of a lesion (e.g., a lesion created via delivery of ablation energy) remains incomplete, which may indicate a lesion that is only temporarily effective (e.g., undesired conduction may occur again in the future). The collected electrical information may indicate continuous conduction through the treatment region, and the mechanical and/or compositional information may suggest the formation of edema rather than a completely transmural (ablative) lesion, which may prompt a change in treatment strategy. The collected electrical information may indicate the elimination of electrical conduction through the region, and the structural and/or compositional information may indicate the formation of a fully transmural (ablative) lesion, which may increase the probability that the lesion will remain effective for a long time, which increases the confidence in the delivered therapy.

As described above, the calculated patient information 95 may include tissue composition information. Tissue composition may be locally assessed by the system 10 via optical measurements (e.g., spectroscopy or fluoroscopy). The system 10 may be configured to determine fluorescence, reflectivity, and/or absorption from tissue (e.g., using a fiber optic or CCD camera-enabled catheter). System 10, via algorithm 255, can assess the extent to which tissue fluoresces, reflects, and/or absorbs light. These responses to specific two or more wavelengths of light may add further specificity, as different biomaterial compositions fluoresce, reflect, and/or absorb light in a specific manner. In some embodiments, system 10 analyzes the lesion by monitoring the fluoroscopic signature of NADH. NADH is a coenzyme present in all intact cells and fluoresces when illuminated with certain wavelengths of light (e.g., UV). Once the cell is damaged (e.g., by RF ablation), NADH is released from the mitochondria of the cell and/or converted to the oxidized form of NADH, and its fluorescence decreases significantly. In some treatment methods, cellular damage is a desired result of a clinical procedure (e.g., an ablation procedure configured to treat cardiac arrhythmias such as atrial fibrillation). However, under some conditions, the response of the tissue and/or other body to the treatment may vary. For example, when attempting to deliver RF ablation to cardiac tissue, the body's inflammatory response accumulates extracellular fluid into the affected area (edema), thereby protecting the cells from further damage. This edema can prevent effective delivery of further RF energy, thus reducing the effectiveness of subsequent delivery of ablation energy. When edema is formed, the cells remain intact and the fluoroscopic marker of NADH remains unchanged, so this fluoroscopic measurement performed by system 10 is highly specific to the desired response of the tissue to the delivered ablation energy (e.g., a condition where cellular damage is associated with lesion formation). This analysis may be performed in conjunction with an assessment of tissue density (also at the energy delivery site) to further refine the assessment of cellular damage relative to healthy tissue. In some embodiments, the system 10 creates a standardized delivery matrix 290' based on one or more patients P2 by recording therapy information related to ablation operations (e.g., cardiac ablation operations) performed on patient P2. The treatment information may include: electrical information, anatomical structure information (e.g., recorded by an imaging device), tissue impedance information. This information may be combined with the measurements of tissue composition, and system 10 (e.g., using machine learning algorithms) may then sensitively and specifically identify an imprint of the tissue composition that may be relevant to the procedure performed on patient P1 without having to make the actual measurement of the composition directly in patient P1.

In some embodiments, the calculated patient information 95 includes Dipole density and/or Surface Charge information using apparatus and methods such as described in applicant's co-pending U.S. patent application Ser. No.16/533,028 entitled "Method and Device for Determining and Presenting Surface Charge and Dipole density on the heart Wall", filed on 6.8.2019, and/or in applicant's co-pending U.S. patent application Ser. No.16/568,768 entitled "Device and Method for the geometrical Determination of electric Dipole density on the heart Wall", filed on 12.9.2019, to determine the dipole density and/or surface charge information, the contents of each of the above applications are incorporated by reference herein in their entirety for all purposes.

In some embodiments, the calculated patient information 95 includes a type of information selected from the group consisting of: pharmacotherapeutic information, electrolyte information, pH information, and combinations thereof.

In some embodiments, system 10 is configured to collect other physiological data of the patient (e.g., data other than data recorded by recording electrodes 311, 321 and/or drive electrodes 411). In these embodiments, the system 10 may include a functional element 99, the functional element 99 including one, two, three, or more sensors or other data acquisition components. In some embodiments, the functional element 99 may include one or more sensors or other functional elements positioned within the patient (functional element 99)_I) And/or one or more sensors or other functional elements (functional element 99) positioned on the skin of the patient_S) Each as shown. Functional element 99_SMay include one or more functional elements positioned on garment 50 and/or within garment 50 (as shown in fig. 1). Functional element 99_IMay include one or more functional elements positioned on the device 100 and/or within the device 100 (e.g., on a basket or other distal portion of the device 100 as shown).

In some embodiments, the functional element 99 includes one or more components configured to collect data selected from the group consisting of: circadian cycle data, cardiac data, respiration data, patient medication data, skin impedance data, perspiration data, thoracic and/or abdominal space data (e.g., as measured manually and/or by an imaging device such as CT or MRI), water weight data, hematocrit level data, wall thickness data (e.g., cardiac wall thickness data), and combinations of these. For example, the functional elements 99 may include manual measurement devices (e.g., tape measures or straightedges) and/or imaging devices (e.g., CT or MRI) for collecting chest measurement information used by the system 10 to determine the transfer matrix 290 and/or the calculated patient information 95. In some embodiments, the functional element 99 includes one, two, three, or more sensors selected from the group consisting of: magnetic sensor, water sensor, perspiration sensorSensor, skin impedance sensor, glucose sensor, pH sensor, PO₂Sensor and pCO₂Sensor, SpO₂Sensors, heart rate sensors, pressure sensors, blood pressure sensors, spine sensors, brain electrodes, brain sensors, flow sensors, blood flow sensors, motion sensors, and combinations of these. In these various embodiments, the algorithm 255 may be configured to include this additional patient information, such as calculating the patient information 95 in an analysis, to determine and/or modify the delivery matrix 290 (e.g., modify the delivery matrix 290 in a continuous and/or intermittent manner), to determine and/or modify system 10 parameters, and/or to perform another function. In some embodiments, the transfer matrix 290 is used to measure cardiac function (e.g., change in blood volume over time) as described herein, such as during cardiac ablation or other cardiac operation.

In some embodiments, the functional element 99 includes one or more electrodes or other transducers configured to deliver electrical signals and/or electrical energy to the patient. For example, the functional element 99 may include one or more electrodes configured to: deliver drive signals (e.g., similar to drive signals 413) for determining transfer matrix 290 (as described herein); delivering a positioning signal; delivering cardiac pacing energy; delivering defibrillation energy; and/or perform another function.

In some embodiments, functional element 99 includes one or more magnets used by system 10 for spatial tracking (e.g., respiratory tracking and/or other patient motion tracking). In these embodiments, the garment 50 may include one or more magnets, such as to position the one or more magnets at one or more predetermined positions relative to the patient.

In some embodiments, the functional elements 99 include one or more ultrasound elements (e.g., sensors and/or transducers) for measuring distance, for example, to create 2D or 3D images of patient tissue and/or devices of the system 10 positioned on and/or within the patient. In these embodiments, the garment 50 may include one or more ultrasound elements, such as to position the one or more ultrasound elements at one or more predetermined positions relative to the patient.

In some embodiments, the functional element 99 comprises a microphone for recording heart sounds, such as a microphone integrated into the patient garment 50 to position the microphone at a particular location relative to the patient.

In some embodiments, functional element 99 includes an accelerometer, such as an accelerometer configured to track movement of a portion of the patient (e.g., when integrated with garment 50), and/or an accelerometer included in another component of system 10 (e.g., included in device 100 to track patient tissue movement and/or device 100 movement).

In some embodiments, one or more drive electrodes of system 10 are positioned at one or more known locations (e.g., in blood within a chamber offset from a heart wall) within a patient (e.g., within a heart of the patient) and emit drive signals (e.g., one or more drive signals) of known amplitude. The system 10 includes one or more recording electrodes positioned at one or more locations (e.g., one or more arbitrary locations) on the surface of the skin of the patient that measure the response to the drive signal. The ratio of these recording signals to the drive signals may be used by the system 10 to generate the transfer matrix 290. These ratios depend on individual patient characteristics (e.g., obesity, heart size, conduction of lungs, organs and other tissues, skin resistance, orientation of the heart, respiratory changes, diaphragm position, etc.). Subsequently, electrical activity (e.g., of the heart) is measured simultaneously with both the internal electrodes (e.g., previously used or otherwise used) and the surface electrodes. Using the transfer matrix 290, the system 10 transforms the electrical activity measured by the surface electrodes to produce a first potential map on the heart wall (e.g., scaled as a ratiometric ratio by the transfer matrix 290 itself).

In some embodiments, system 10 generates a map of potentials on the heart wall while avoiding the use of inverse solutions, such as when passing through voltage V at point "i" on the heart wall_iThe voltage value W on the body surface_kLinear relation of (1)The voltage V is determined (e.g., via algorithm 255)_iFor example, by using the following equation (1):

equation (1):

the driving signal is applied to "k" Surface Electrodes (SE)_k) And at "i" heart wall electrodes (HW)_i) Upper measurement response V_i. In the sum of equation (1), there is only one term for which:

thus, W_kIs measured and, according to equation (1), is passed through with M_ikMultiplied by itself to give V_i. In these embodiments, system 10 may include a minimum number of surface electrodes (e.g., electrodes 312 configured as drive electrodes) that provide drive signal k_SAnd/or 322_S) For example at least 3, at least 6, at least 9 or at least 12 surface electrodes.

In some embodiments, the system 10 applying the transfer matrix 290 to the first set of recorded signals 313 includes applying a ratiometric function of the transfer matrix 290 to the first set of recorded signals 313. The ratiometric function may include an "identity function" for which the resulting set of recorded values (e.g., the calculated patient information 95) is determined (e.g., only by the transfer matrix 290 itself). The ratiometric function may also be configured to linearly scale the transfer matrix 290 to a "linear scale function". Alternatively or additionally, the ratiometric function may be configured to scale the transfer matrix 290 non-linearly (e.g., as a "non-linear scaling function").

In some embodiments, the system 10 applying the transfer matrix 290 to the first set of recorded signals 313 includes applying a non-linear geometric function of the transfer matrix 290 to the first set of recorded signals 313.

In some embodiments, system 10 transforms the electrical activity measured by the inner electrodes (e.g., using inverse solution) to produce a second potential map on the heart wall. The system 10 may be configured to generate a third map of electrical potentials on the heart wall based on the first map and the second map, wherein the third map is more accurate than either the first map or the second map alone. Alternatively, avoiding the use of internal electrodes, the system 10 is configured to generate a cardiac wall potential data map using only surface electrodes. For example, the transfer matrix 290 may be determined using patient P2 and cardiac electrical activity calculated for individual patient P1, such as when patient P2 has similar heart size or other similar characteristics as patient P1. The similarity between patients P2 and P1 can be assessed and correction factors employed to account for differences (e.g., differences in weight, size, heart size, etc.).

In some embodiments, the system 10 records voltage information at a first alpha position and determines electrical activity information at a second, different beta position. For example, recording electrodes 311 (e.g., positioned on the patient's skin) may record voltages, and system 10 may produce calculated patient information 95 including electrical activity information at target location 90, target location 90 including a location within the patient's body, such as on and/or within a patient's organ (such as the heart or brain). In some embodiments, the electrical activity information includes voltage information, Surface Charge information, and/or Dipole density information, such as the applicant's co-pending U.S. patent application serial No.16/533,028 entitled "Method and Device for Determining and Presenting Surface Charge and Dipole density on heart Walls" filed on 6.8.2019, and/or applicant's co-pending U.S. patent application serial No.16/568,768 entitled "Device and Method for the geometrical Determination of Electrical Dipole Densities on the heart Wall", filed on 12.9.2019, the contents of each of which are incorporated herein in their entirety for all purposes. In these embodiments, the calculated patient information 95 may be determined using an inverse solution, such as an inverse solution used in conjunction with the transfer matrix 290, to improve the accuracy of the calculated patient information 95. The system 10 may use the transfer matrix 290 to compensate for spatial and/or temporal anisotropy.

In some embodiments, the system 10 includes: device 100, the device 100 comprising one or more electrodes (e.g., one or more electrodes 411) configured to record electrical activity from within a patient's heart_IAnd/or electrode-based functional elements 99_I) (ii) a One or more electrodes positioned (e.g., via garment 50) on the skin of the patient configured to record electrical activity on the surface of the patient; and an algorithm 255, the algorithm 255 configured to calculate electrical information (e.g., voltage information, dipole density information, and/or surface charge information) of the heart. In these embodiments, the algorithm 255 may use the recorded electrical activity from within the patient's heart and from the surface of the patient to calculate an inverse solution to determine the electrical information. In some embodiments, the inverse solution is constrained (limited) to the normal, strictly tangential, and/or strictly scalar density magnitudes of the dipoles. In these embodiments, additional recorded data (surface data) may be used to "double-constrain" the inverse solution, or to provide a validation or correction data set to improve the accuracy of the inverse solution. Alternatively or additionally, the additional recorded data (surface data) sufficiently constrains the inverse solution such that the inverse solution may allow for vector dipoles with unconstrained directions (i.e., a linear combination of normal and tangential dipoles). In some embodiments, additional recorded data (surface recorded data) may be used to calculate electrical information of the heart by applying algorithm 255 at locations on the surface of the heart (e.g., on a three-dimensional shell without thickness). In some embodiments, the application algorithm 255 may use additional recorded data (surface recorded data) for calculating electrical information of the heart within the tissue and/or throughout the tissue (through or throughout transmural thicknesses of one or more heart chambers, and/or within a three-dimensional structure that includes variations in tissue thickness representative of the structural anatomy, such as myocardial tissue between the endocardium and epicardium, atrial septum, ventricular septum, etc.). In some embodiments, algorithm 255 may use additional recorded data (surface data) to improve one or more heart bitsAccuracy of the inverse solution at a location, such as one or more left atrial locations (e.g., locations proximate to the pulmonary veins, left atrial appendage, and/or mitral valve). In some embodiments, the internal and surface registration data may be registered simultaneously and used by algorithm 255 to improve modeling of the ventricular component of the electrical information, such as for V wave (QRST) removal.

As described above, the system 10 may be configured to perform positioning operations, such as an operation to determine the location of one or more portions of the device 100 and/or an operation to determine the location of another device that has been inserted into the patient. In these embodiments, the system 10 may be configured to utilize the transfer matrix 290 to improve the accuracy of the location information. In some embodiments, the system 10 may be configured to improve accuracy in real-time or at least near real-time (referred to herein as "real-time") throughout a patient operation (e.g., a patient mapping and/or ablation operation). In some embodiments, system 10 is configured to use skin-placed electrodes (e.g., electrode 311)_S、321_S、411_SAnd/or electrode-based functional elements 99_S) And performing real-time updating of the positioning data by continuously transmitting and recording the determined electrical information by the inner and outer electrodes.

In some embodiments, system 10 includes a distribution of electrodes configured for a plurality of purposes, such as a plurality of electrodes positioned at specific locations relative to the patient's anatomy on and/or proximate to (herein "on") the patient's skin via garment 50. In some embodiments, such as described herein, a plurality of electrodes are used to determine electrical information related to the heart of a patient, such as a voltage map, dipole density map, and/or surface charge map of the surface of the heart. In some embodiments, one or more of the electrodes (e.g., electrodes 311, 321 and/or electrode-based functional elements 99) are configured to deliver electrical signals and/or electrical energy, such as to perform positioning operations, deliver cardiac pacing energy, deliver defibrillation energy, and/or deliver therapy energy. In some embodiments, one or more electrodes are configured to provide an electrical ground (e.g., a return path for one or more signals, such as a return path for delivering ablation energy) and/or a reference signal (e.g., a reference voltage).

In some embodiments, system 10 includes a first set of one or more electrodes for positioning on the skin of the patient (e.g., via garment 50) to perform a first function, and a second, different set of one or more electrodes for positioning on the skin of the patient (e.g., via garment 50) to perform a second, different function. For example, one set of electrodes may include a size and/or set of materials configured to perform cardiac pacing and/or fibrillation, while a different set of electrodes includes a size and/or set of materials configured to record electrical signals.

In some embodiments, system 10 includes a set of multiple electrodes that are multiplexed (e.g., via a switching network) such that a first subset of one or more electrodes are used for a first function and one or more different additional subsets of one or more electrodes may be used for different functions. For example, a subset may be used to record signals to create a voltage, surface charge, and/or dipole density map of the surface of the heart, a subset may be used to create an ECG (e.g., ECGi and a subset for a 12-lead ECG), a subset may be used to pace the patient's heart, a subset may be used to defibrillate the patient's heart, a subset may be used as an electrical ground, and/or a subset may be used as a reference signal. In some embodiments, the subset of electrodes used for a particular function may be modified by an operator of system 10, such as during operation to improve recording and/or energy delivery.

In some embodiments, one or more functions of the system 10 (e.g., positioning, defibrillation, and/or other functions described above) may be optimized or at least improved (herein "optimized") during patient operation, such as to adjust for patient-specific and/or environment-specific conditions. In some embodiments, the system 10 may include a plurality of electrodes interconnected (grouped) in one or more groups of electrodes, such as one or more groups of electrodes each performing a function (e.g., a diagnostic function and/or a therapeutic function). In some embodiments, particular sets of electrodes (e.g., sets of electrodes for particular functions) are predefined and/or automatically adjusted by system 10. Alternatively or additionally, a particular set of electrodes may be selected and/or adjusted by a user of the system 10 (e.g., a clinician of a patient). Different groups may be configured to perform different functions. Additionally or alternatively, different groups may be configured to perform the same function, such as when a first group of electrodes is used to perform the function, after which a second group is used to perform the same function, such as to optimize the performance of the function. In some embodiments, a combination of multiple sets of electrodes is configured to perform a single function, e.g., multiple sets of one or more electrodes are configured as "site patches".

For example, the system 10 may be configured such that multiple sets of one or more electrodes are configured as site patches that are dynamically adjustable without having to remove and reapply the electrodes. These sets of electrodes may be set and/or adjusted (e.g., to select or adjust electrodes at particular anatomical locations), such as to modify the cross-axes and/or include additional axes in the adjustment. For example, in cardiac operations, a lateral shift of 1-2 pairs of electrode sets may be performed, such as to account for the right heart (the heart is more right).

In another example, system 10 may be configured such that multiple sets of one or more electrodes are configured as cardiac pacing electrodes and/or defibrillation electrodes, which sets may be dynamically adjusted to optimize pacing and/or defibrillation without having to remove and reapply the electrodes. In some embodiments, pacing and/or defibrillation electrode placement is selected based on physician preference. In some embodiments, one or more pacing and/or defibrillation electrodes, which are also used for different function(s), are disconnected from other functional circuitry prior to delivery of pacing and/or defibrillation energy. For example, after delivering pacing and/or defibrillation, the system 10 may be configured to rapidly switch one or more of the electrodes (and/or other electrodes) to a mapping mode, such as recording cardiac electrical information shortly after pacing and/or defibrillation, allowing for the creation of a pace recovery, defibrillation recovery, and/or a map of arrhythmic episodes (e.g., atrial fibrillation episodes). Alternatively or additionally, the system 10 may be configured to deliver electrical energy to a non-cardiac organ of the patient, such as the patient's brain, such as to treat a neurological condition, such as epilepsy, migraine, depression, or the like.

In another example, the system 10 may be configured such that multiple sets of one or more electrodes may be selected to deliver energy in a particular pattern, such as to optimize energy delivery to one location (e.g., the patient's heart, brain, and/or another organ). For example, one or more sets of energy delivery electrodes may be switched and/or adjusted to successfully cardiovert a patient's heart, and/or to prevent or at least reduce seizures. In some embodiments, the pattern of electrodes is selected to reduce the required energy delivery. In some embodiments, a spiral pattern of electrodes may be included. In some embodiments, the pattern of electrodes may be adjusted based on the mapped electrical activity (e.g., of the heart or brain) and/or the physiological matrix (e.g., of the heart or brain).

In some embodiments, system 10 is configured to determine transmural conduction within cardiac tissue (e.g., endocardium to epicardium, or vice versa), such as when algorithm 255 analyzes sensors (e.g., electrodes 311) placed on the patient's skin (e.g., via garment 50)_S、321_S、411_SAnd/or electrode-based functional elements 99_S) Data recorded and by sensors in the patient (e.g. via the device 100, e.g. electrodes 311_I、321_I、411_IAnd/or electrode-based functional elements 99_I) The data recorded. Algorithm 255 may use one or more boundary conditions, such as endocardial, epicardial, and/or pericardial voltages (e.g., as measured directly and/or determined indirectly by system 10) to make the determination. As described above, algorithm 255 may utilize additional recorded data (e.g., surface data) to "double constrain" mathematical transformations (e.g., inverse solutions) and/or provide validation or correction data sets to improve the accuracy of the output of algorithm 255.

Referring now to FIG. 1A, there is shown a schematic diagram of a system for calculating information related to one or more parameters of a patient's heart, consistent with the principles of the invention. The system 10 of FIG. 1A may have a similar construction and arrangement as the system 10 of FIG. 1 described above, and it may include similar components. In the embodiment of fig. 1A, the system 10 is arranged and configured to calculate patient information 95 relating to the patient's heart, such as information relating to one or more target locations 90 in the patient's left atrium. The patient information 95 may be determined using the transfer matrix 290 and may be based on signals 313 recorded by one or more recording electrodes 311 positioned at one or more skin-based recording locations 312. The recording signal 313 may be recorded by the recording component 300 (e.g., and stored in the memory 252 of the processing unit 250). The recording electrode 311 may be included in the patient garment 50, and/or the patient garment 50 may simply be used as a template to position the electrode 311 at a particular anatomical location on the patient's skin.

In some embodiments, the system 10 is configured to determine the transfer matrix 290, such as when the system 10 includes one or more drive electrodes 411 positioned at one or more drive locations 412 and configured to deliver drive signals 413 (e.g., the drive signals 413 provided by the signal generator 400). In these embodiments, a set of recording electrodes 321 is included, and the set of recording electrodes 321 is positioned at location 322 to record signal 323. In the embodiment shown in fig. 1A, the drive electrode 411 is positioned at a drive location 412 within the patient (e.g., the drive electrode 411 is included in an expandable cage or other distal portion of the body-inserted device 100, such as at a location within a chamber of the patient's heart), and the recording electrode 321 is positioned at a location 322 on the patient's skin. In some embodiments, recording location 322 is the same as or at least similar to recording location 322 shown in fig. 1A (e.g., recording electrode 321 is the same as or at least similar to recording electrode 311). Alternatively, recording electrode 321 comprises a different electrode and/or recording location 322 comprises a different location than recording electrode 311 and recording location 312, respectively. The algorithm 255 may generate the transfer matrix 290 based on an analysis of the recorded signal 323 compared to the drive signal 413.

Referring now to FIG. 2, a flow chart of a method of determining patient information at a target location is shown, consistent with the present inventive concept. The method 2000 of fig. 2 provides a method of recording electrical activity at one or more recording locations and applying a transfer matrix to the recordings to determine patient information at one or more target locations. Method 2000 will be described using system 10 and the various components of system 10 described above with reference to fig. 1.

In step 2100, a transfer matrix 290 is determined. The transfer matrix 290 may be determined based on information recorded from a single patient (e.g., patient P1 described above with reference to fig. 1) and/or multiple patients (e.g., patient P1, P2, and/or other mammalian patients). As described above with reference to fig. 1, the transfer matrix 290 may be determined by generating a drive signal 413 from one or more recording locations 322 via a set of one or more recording electrodes 321. In some embodiments, the transfer matrix 290 is determined as described below with reference to fig. 3.

In step 2200, the potential is recorded. For example, a first set of recording electrodes (recording electrodes 311) records the potentials at a first set of recording locations (recording locations 312) to create a set of recording signals (recording signals 313 stored in console 200), as described above with reference to FIG. 1.

In step 2300, patient information is calculated. For example, the patient information 95 may be calculated for a set of target locations, such as the target location 90 including one or more locations on and/or within the patient. The patient information 95 may be calculated by applying the transfer matrix 255 to the recorded signals 313, such as described above with reference to fig. 1.

Referring now to fig. 3, a flow chart of a method of determining a transfer matrix and subsequently using the transfer matrix to determine patient information at a target location, consistent with the present concepts, is shown. Method 3000 of fig. 3 provides a method of determining a transfer matrix. The method also provides for recording electrical activity at one or more recording locations, and applying a transfer matrix to the recording to determine patient information at one or more target locations. Method 3000 will be described using system 10 and the various components of system 10 described above with reference to fig. 1.

In step 3050, a drive signal is emitted or otherwise delivered to the tissue from one or more drive locations 412, e.g., via a set of one or more drive electrodes 411. The drive signal 413 is recorded, for example, via a set of one or more recording electrodes 321 from one or more recording locations 322, to create a set of recording signals 323 that may be stored in the console 200, such as described above with reference to fig. 1.

In step 3100, the transfer matrix 290 is determined based on the recording signal 323 recorded in step 3050.

In step 3200, the potential is recorded. For example, a first set of recording electrodes (recording electrodes 311) records the electrical potentials at a first set of recording locations (recording locations 312) to create a set of recording signals (recording signals 313 stored in console 200), as described above with reference to fig. 1 and/or 2.

In step 3300, patient information is calculated. For example, the patient information 95 may be calculated for a set of target locations, such as the target location 90 including one or more locations on and/or within the patient. The patient information 95 may be calculated by applying the transfer matrix 255 to the recorded signals 313, such as described above with reference to fig. 1 and/or 2.

The above embodiments should be understood as serving only as illustrative examples; further embodiments are envisaged. Any feature described herein in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.