阅读说明：本技术 一种血管内植入物固定保持结构和一种血管内植入物输送系统 (Implant fixing and holding structure in blood vessel and implant conveying system in blood vessel ) 是由 贾晶 张捷捷 吴重草 胡天宙 刘振全 孙冰 于 2021-01-22 设计创作，主要内容包括：本发明提供一种血管内植入物固定保持结构和一种血管内植入物输送系统,血管内植入物固定保持结构用于在血管内植入物输送过程中进行植入物的固定、保持及分离动作。血管内植入物输送系统包括：输送管,贯穿输送管的导丝,及连接在导丝上的支持器。在输送初期,导丝与输送管保持相对固定,支持器位于输送管头部并对植入物起固定作用；在输送后期,导丝与输送管发生相对运动,支持器从输送管头部伸出,植入物实现释放。当植入物伸出输送管远端长度不超过一定数值时,植入物可通过导丝回收至输送管内调整位置重新释放。根据本发明,提供了一种灵活性好、成功率高、具有反复回撤和重新释放功能、并能适应多种微导管的血管内植入物输送系统。(The invention provides a fixing and retaining structure of an implant in a blood vessel and a delivery system of the implant in the blood vessel. An endovascular implant delivery system comprising: the catheter comprises a delivery tube, a guide wire penetrating through the delivery tube, and a support connected to the guide wire. In the initial stage of delivery, the guide wire and the delivery pipe are kept relatively fixed, and the support is positioned at the head of the delivery pipe and plays a role in fixing the implant; in the later period of delivery, the guide wire and the delivery pipe are relatively moved, the support extends out of the head part of the delivery pipe, and the implant is released. When the length of the implant extending out of the far end of the conveying pipe does not exceed a certain value, the implant can be recovered to the position in the conveying pipe through the guide wire and released again. According to the present invention, an intravascular implant delivery system is provided that is flexible, has a high success rate, has repeated withdrawal and re-release functions, and can accommodate a variety of microcatheters.)

1. An endovascular implant fixation retention structure for fixation, retention, and detachment of an endovascular implant during delivery of the endovascular implant, comprising:

a support fixed to the guide wire and movable by the guide wire at the distal end of the delivery tube;

the endovascular implant is L in length, a tail part of the endovascular implant at least partially covers the support, the support and/or the delivery pipe are matched in size, the tail part of the endovascular implant is fixed and held, and the endovascular implant is pushed through the guide wire;

during the advancing, the endovascular implant is retrievable through the guidewire when the endovascular implant extends no more than 0.98L beyond the distal end of the delivery tube, and

when the protrusion length of the endovascular implant from the distal end of the delivery tube is greater than 0.98L, the tail of the endovascular implant loses fixation with the holder and/or the inner wall of the delivery tube, and the endovascular implant is detached from the holder and/or the delivery tube.

In the endovascular implant fixation retention structure, one or more radially extending protruding supports are fixed to the guide wire.

2. An endovascular implant fixation retention structure according to claim 1, wherein the holder is connected to the guide wire in a point connection, a line connection or a surface connection.

3. An endovascular implant fixation retention structure according to claim 1 or 2, wherein a tail portion of the endovascular implant is in point contact, line contact or surface contact with the outlet holder.

4. An endovascular implant fixation retention structure according to claim 1, wherein the holder is integrally formed with the guide wire.

5. An endovascular implant fixation retention structure according to claim 1, wherein the support is connected to the guide wire with a cross-section in a direction perpendicular to the direction of extension of the guide wire showing a continuous or a discontinuous combination of segments. An endovascular implant fixation retention structure according to claim 1, wherein the holder is a rigid structure.

6. An implant fixation retention structure in a vessel according to claim 1, characterized in that the holder is deformed at least in part by force.

7. An implant fixation holding structure in a blood vessel according to claim 1, wherein a ratio of an area of a junction of the holder and the guide wire to a projected area of the holder on a surface of the guide wire is (0.01-1): 1.

8. An endovascular implant fixation retention structure according to claim 1, wherein the holder has a length in a direction along which the guide wire extends in a range of 0.1mm-1000 mm.

9. An endovascular implant fixation retention structure according to claim 1, wherein a ratio of an axial overlap length of the holder with the delivery tube to an axial extension length of the holder is (0.001-1): 1.

10. An endovascular implant fixation retention structure according to claim 1, wherein the holder is preformed and connected to the guide wire by bonding or welding or mechanical connection; the preforming means includes one or more of curing, winding, braiding, cutting, etching, injection molding, casting, forging, stamping, welding, machining, assembling, extruding, etc.

11. An endovascular implant delivery system comprising an endovascular implant fixation retention structure according to any one of claims 1-10, wherein the endovascular implant delivery system comprises:

a delivery pipe;

a guide wire disposed within the delivery tube, a distal end of the guide wire having attached thereto a holder according to claims 1-7.

12. The endovascular implant delivery system of claim 11, having a visualization element thereon for positional reference of an actual delivery position of the endovascular implant during delivery.

Technical Field

The present invention relates to medical instruments, and more particularly, to an endovascular implant fixation retention structure, and an endovascular implant delivery system including the same.

Background

Problems with the prior art for delivery of endovascular implants include:

1) it is common in the surgical procedure that endovascular implants are inaccurately positioned in the vessel and not placed in the desired location by the physician, and it is therefore desirable to retrieve endovascular implants into the delivery tube before their final release, and to re-release them after adjustment of the position. In the prior art, the endovascular implant either cannot be recycled, or the recycling is difficult when the length of the released endovascular implant exceeds 50% of the total length of the endovascular implant; however, the degree that the release of the endovascular implant does not exceed 50% has no obvious effect on the doctor to judge whether the correct position is reached, and if the delivery system can realize 90% release of the endovascular implant, the endovascular implant can still be recovered, and the position of the endovascular implant is basically determined, so that whether the release is successful or not can be judged better.

2) Patent CN108260342A describes a releasable delivery system comprising a delivery pusher consisting of an elongate member and an endovascular implant engagement mechanism located on a distal portion of the elongate member, and an endovascular implant having a proximal loop. The release delivery system is primarily secured by a mesh structure that hooks over the tail of the endovascular implant in a manner that, during actual therapeutic delivery, may, with changing clinical circumstances, result in the potential for incomplete detachment of the release delivery system, resulting in a failure to detach the delivery pusher from the endovascular implant with the proximal loop. Moreover, the system can be used only by being matched with the endovascular implant with the proximal ring and the delivery sheath, and the demand on the endovascular implant is higher; also, the system requires the use of a delivery sheath of a particular inner diameter size to avoid separation of the endovascular implant from the delivery pusher during use, which imposes a high requirement on the size of the delivery cannula.

3) Prior art intravascular implant delivery systems typically require use with microcatheters of a particular inner diameter, such as 0.027 "inner diameter, with limited application.

The present invention thus provides new improvements and several advantages in the field of delivery of endovascular implants: the delivery system can realize the repeated recovery of the implant in the blood vessel when the length of the released implant in the blood vessel exceeds 95 percent of the total length of the implant in the blood vessel, and is convenient for a doctor to more accurately position in the operation process. The requirement on the structure of the implant in the blood vessel is low, the release of the implant in the blood vessel is simple and easy to operate, and meanwhile, the delivery system has low requirement on the inner diameter of the micro catheter, is suitable for various types of micro catheters, can be used for all the micro catheters with the inner diameters larger than that of the delivery pipe, and is convenient for operation.

Disclosure of Invention

The invention provides a fixing and retaining structure of an endovascular implant, which realizes the fixing, retaining and separating of the endovascular implant and a delivery system through a support fixed on a guide wire in the delivery process of the endovascular implant.

The invention provides an implant fixing and holding structure in blood vessels, which comprises a support fixed on a guide wire and moved at the far end of a conveying pipe through the guide wire.

The invention provides a fixing and retaining structure of an endovascular implant, which is characterized in that the support and/or the delivery pipe are matched in size, the tail part of the endovascular implant is fixed and retained, and the endovascular implant is pushed through the guide wire.

During the pushing process, the endovascular implant can be retrieved into the delivery tube and released again through the guide wire when the protruding length of the endovascular implant out of the distal end of the delivery tube is within a certain ratio to the length of the endovascular implant, and the ratio is not more than 0.98. After the ratio is exceeded, the endovascular implant is released from the delivery tube to achieve release.

The invention provides an endovascular implant delivery system comprising an endovascular implant fixation and retention structure as described above, the delivery system consisting of a delivery tube, a guide wire, and a holder secured to the guide wire. The holder may be one or more.

The present invention provides an endovascular implant fixation retention structure, the holder being disposed at least partially within the distal end of the delivery tube.

The invention provides an implant fixing and retaining structure in a blood vessel, wherein the connection mode of the support and the guide wire is point connection, line connection or surface connection.

The invention provides a fixing and retaining structure of an implant in a blood vessel, wherein the tail part of the implant in the blood vessel is in point contact, line contact or surface contact with the extraction and support device.

The invention provides an implant fixing and holding structure in blood vessels, and the section of the connection part of the holder and the guide wire in the direction vertical to the extension direction of the guide wire is displayed as a continuous or discontinuous combination of a plurality of sections.

According to some embodiments of the invention, the holder is a rigid structure.

According to some embodiments of the invention, the holder is deformed at least in part by the force.

The invention provides an implant fixing and retaining structure in a blood vessel, wherein the ratio of the area of the connection part of a support and a guide wire to the projection area of the support on the surface of the guide wire is (0.01-1): 1.

the invention provides an implant fixing and holding structure in blood vessel, the length of the support along the extending direction of the guide wire is 0.1mm-1000 mm.

The invention provides a fixing and retaining structure of an implant in a blood vessel, wherein the ratio of the axial overlapping length of a support and a conveying pipe to the axial extension length of the support is (0.001-1): 1.

the invention provides a fixing and retaining structure of an implant in a blood vessel, wherein the support is preformed and then connected with a guide wire through bonding or welding or mechanical connection; the preforming means includes one or more of curing, winding, braiding, cutting, etching, injection molding, casting, forging, stamping, welding, machining, assembling, extruding, etc.

The present invention provides an intravascular implant delivery system having a visualization element identification element location made of a radiopaque material, including but not limited to gold, platinum-tungsten alloy, platinum-iridium alloy, or a developable polymer.

The present invention provides new improvements and the following advantages in the field of delivery of endovascular implants:

(1) the delivery system can realize the repeated recovery of the implant in the blood vessel when the length of the released implant in the blood vessel exceeds 95 percent of the total length of the implant in the blood vessel, and is convenient for a doctor to more accurately position in the operation process.

(2) The delivery system of the present invention has low requirements for endovascular implant structures. The prior art release delivery systems require a mesh or loop structure that hooks over the tail of the endovascular implant and therefore need to be used with endovascular implants having a proximal loop, arm member, or marker coil, etc., and a delivery sheath. According to the invention, only pressure and friction can be used as acting force for realizing fixation, holding and relative position change between the endovascular implant and the delivery system, the endovascular implant can be fixed and held by matching the size and the position of the endovascular implant, and no other hooking is generated, so that the endovascular implant is not required to have a special tail structure, and the system is suitable for various endovascular implants including dense mesh stents, occluders and spring rings.

(3) The delivery system of the invention releases implant in blood vessel and is simple and easy to operate, the fixation, the maintenance and the relative position change are realized by the relative movement of the guide wire and the delivery pipe, and the delivery system can be directly operated manually without introducing additional devices, channels and thermally or electrically driven pushers; but simultaneously can also use with the cooperation of corresponding propelling movement appurtenance, has higher flexibility.

(4) The delivery system has low requirement on the inner diameter of the micro catheter, and the micro catheter can be used when the inner diameter is larger than the outer diameter of the delivery tube, so that doctors can conveniently select the model suitable for the operation.

Drawings

Fig. 1 is a schematic longitudinal cross-sectional view of the present endovascular implant delivery system in a delivery configuration;

FIG. 2 is a corresponding relationship of the length of an endovascular implant extending out of the distal end of the delivery tube to the length of the endovascular implant;

FIG. 3 shows the correspondence between the inner diameter of the head of the transfer tube and the maximum outer diameter of the holder;

fig. 4-10 illustrate several shapes of holders and combinations with guide wires.

Fig. 11-16 show several outer profile shapes of the holder in the delivery configuration.

Fig. 17 illustrates relative positioning of an implant retention structure of an endovascular implant during deployment with the endovascular implant, the system in an initial delivery configuration;

fig. 18 is a relative positioning of the system in a late delivery configuration during actuation of the endovascular implant fixation retention structure with an endovascular implant;

fig. 19 is a relative position of the system in a release configuration during actuation of an endovascular implant fixation retention structure with an endovascular implant.

Wherein the reference numbers are as follows:

1-delivery tube, 2-guide wire, 3-endovascular implant, 201-support, 202-visualization element.

Detailed Description

To make the objects, advantages and features of the present invention more apparent, the endovascular implant fixation retention structure proposed by the present invention, and an endovascular implant delivery system including the same, are described in further detail below with reference to fig. 1 to 6. It should be noted that the drawings are simplified in form and not to precise scale, are only used for convenience and clarity to aid in describing the embodiments of the present invention, and are not used for limiting the implementation of the present invention, so that the present invention has no technical significance, and any structural modification, change of proportion relation or adjustment of size should still fall within the scope of the technical content disclosed by the present invention without affecting the function and the achievable purpose of the present invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. The term "comprising", without further limitation, means that the element so defined is not excluded from the group consisting of additional identical elements in the process, method, article, or apparatus that comprises the element.

In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.

The present invention will be further described with reference to the following specific examples. It should be understood that the following examples are illustrative only and are not intended to limit the scope of the present invention.

The delivery systems of the present disclosure may be used to deliver a variety of endovascular implants, such as various dense mesh stents, occluders, coils, or other implants. For convenience, a close-mesh stent schematic is illustrated in the figures.

The delivery tube of the present description is a lumen structure containing a circular, elliptical or polygonal internal lumen, and the term "delivery tube" is used throughout the description for convenience.

The micro-catheter in the present specification is a medical device which is matched with the delivery system to complete the delivery, withdrawal and release processes of the implant in the blood vessel in the process of operation, such as micro-catheters, guide catheters, middle catheters, access catheters and delivery sheaths with various sizes. The term "microcatheter" is used throughout the specification for convenience.

In this specification, the term "release" describes the process of separating the endovascular implant from the delivery system, and the term "withdrawal" describes the process of partially detaching the endovascular implant from the microcatheter, yet allowing it to be retrieved back into the microcatheter by the delivery system. The endovascular implant maintains a fixation, retention action with the delivery system before release, and can be withdrawn one or more times.

The pre-release configuration of the endovascular implant is referred to herein collectively as the "delivery configuration".

Because the implant in blood vessel usually has certain elasticity, the natural state and the holding state under the action of different external forces have different actual lengths. In the present description, reference to the length of an endovascular implant refers to the length of the implant when it is fully inside the delivery tube; when the endovascular implant extends out of the distal length of the delivery tube, it corresponds to the exact same length of endovascular implant when in the delivery tube.

Referring to fig. 1, the present invention provides an endovascular implant fixation retention structure, and an endovascular implant delivery system including the same. The endovascular implant delivery system comprises a delivery tube 1 and a guide wire 2 for securing, retaining and detaching the endovascular implant 3. The implant fixing and holding structure in the blood vessel comprises a support 201, wherein the support 201 is fixed on a guide wire 2, is wholly or partially arranged in the lumen of a delivery pipe 1 and can move along with the guide wire 2 in the lumen of the delivery pipe 1.

The motion of the implant in blood vessel is realized by the relative position between the tail part and the holder and the delivery pipe. The tail part of the implant in the blood vessel is clamped by the support and the delivery pipe, and the implant in the blood vessel is fixed and kept through the matching of the size and the position of the three; meanwhile, the guide wire connected with the support can push the implant in the blood vessel, change the relative positions of the three and perform separation action. In the pushing process, the effect of pressure, friction or other interaction force exists between the implant in the blood vessel and the holder and/or the inner wall of the delivery pipe, and the acting force for realizing fixation, holding and relative position change among the implant in the blood vessel, the holder and/or the inner wall of the delivery pipe is realized; when the holder is extended from the distal end portion or all of the delivery tube, the interaction between the endovascular implant and the holder and/or the inner wall of the delivery tube is lost, the fixation between the three is lost, and the endovascular implant is separated from the delivery tube.

Or, in other schemes, the holder 201 is completely arranged outside the lumen of the delivery pipe 1, the endovascular implant 3 is sleeved on the holder 201, and the tail part of the endovascular implant 3 can be inserted into the lumen of the delivery pipe 1 according to actual needs:

when the tail part of the endovascular implant 3 does not extend into the lumen of the delivery pipe 1 at this time, the endovascular implant 3 and the holder 201 are fixed through size matching;

when the tail part of the endovascular implant 3 extends into the lumen of the delivery pipe 1 at this time, the endovascular implant 3, the holder 201 and the delivery pipe 1 are fixed by size matching.

According to the present invention, when the length of the endovascular implant extending beyond the distal end of the delivery tube does not exceed a certain value, the endovascular implant may be retrieved into the delivery tube by a guidewire. The length of the endovascular implant is L, the endovascular implant can be retrieved through the guide wire when the endovascular implant extends out of the distal end of the delivery tube by a length not greater than 0.98L during the pushing process, and the tail of the endovascular implant loses the fixation with the holder and/or the inner wall of the delivery tube when the endovascular implant extends out of the distal end of the delivery tube by a length greater than 0.98L, the endovascular implant is separated from the holder and/or the delivery tube.

Referring to fig. 2, the extension length of the endovascular implant from the distal end of the delivery tube corresponds to the length of the endovascular implant for effective withdrawal. The length distribution in the interval can realize the withdrawing action of the implant in the blood vessel. The maximum ratio of the length of the endovascular implant extending out of the distal end of the delivery tube to the length of the endovascular implant increases with increasing length of the endovascular implant. When the endovascular implant has a shorter overall length, the corresponding maximum ratio is relatively small, and when the endovascular implant has a longer overall length, a higher maximum ratio can be achieved.

Preferably, when the total length of the endovascular implant is not more than 5mm, the endovascular implant capable of being recycled extends out of the distal end of the delivery pipe by a length of not more than 0.8L; when the total length of the endovascular implant exceeds 100mm, the length of the endovascular implant capable of being recovered, which extends out of the distal end of the delivery tube, can reach 0.98L.

Preferably, for a typical vascular implant within 5-100mm in length, the intravascular implant extends 0.8L-0.95L out of the distal end of the delivery tube for a suitable release profile.

According to a preferred embodiment of the invention, the support has a ratio of the maximum diameter of the cross-section perpendicular to the guide wire to the inner diameter of the head of the delivery tube in the natural, non-crimped state of (0.1-10.0): 1. The correspondence between the inner diameter of the head of the duct and the maximum outer diameter of the holder is shown in connection with fig. 3. The holder, the guide wire and the implant in the blood vessel have certain volumes, and when the size of the delivery pipe is smaller, the proportion of the holder, the guide wire and the implant in the blood vessel to the inner diameter of the head of the delivery pipe is larger. In connection with the preferred embodiment of the present invention, the preferred length combinations are represented by the arrays (A ', B'), where A 'represents the inner diameter of the head of the transfer tube and B' represents the maximum outer diameter of the holder, and the length is in millimeters (mm).

Preferably, when the inner diameter of the head of the delivery pipe is 0.1-0.3mm, the ratio of the maximum section size of the support in the direction vertical to the guide wire to the inner diameter of the delivery pipe in the natural non-pressure holding state is (0.01-2): 1. Preferred length combinations include (0.26, 0.33), (0.27, 0.21).

Preferably, when the inner diameter of the head of the delivery pipe is 0.3-0.6mm, the ratio of the maximum section size of the holder in the direction vertical to the guide wire to the inner diameter of the delivery pipe in the natural non-pressure holding state is (0.1-5): 1. preferred length combinations include (0.36, 0.53), (0.36, 0.6), (0.36, 0.77), (0.4, 0.37), (0.4, 0.44), (0.4, 0.58), (0.4, 0.66), (0.4, 0.83), (0.49, 0.42), (0.52, 0.41), (0.52, 0.44), (0.55, 0.53), (0.55, 0.78), (0.55, 0.88).

Preferably, when the inner diameter of the head of the delivery pipe is 0.6-1.0mm, the ratio of the maximum cross-sectional dimension of the holder in the direction perpendicular to the guide wire to the inner diameter of the delivery pipe in the natural non-pressure holding state is (0.2-10): 1. preferred length combinations include (0.61, 0.77), (0.62, 0.45), (0.7, 0.5), (0.7, 0.88), (0.7, 0.93), (0.8, 1.28), (0.82, 1.43), (1, 0.99).

Preferably, when the inner diameter of the head of the delivery pipe is larger than 1.0mm, the ratio of the maximum cross-sectional dimension of the support in the direction vertical to the guide wire to the inner diameter of the delivery pipe in the natural non-pressure holding state is (0.5-10) to 1. Preferred length combinations include (1.2, 1.53), (1.2, 1.6), (1.5, 1.8) (1.6, 1.99).

According to the present invention, as shown in fig. 4-10, there are several shapes of the holder and the combination with the guide wire in the fixing and holding structure of the implant in blood vessel provided according to the present invention. On a single guide wire, one or more radially extending protruding supports are typically fixed. The holder may be connected to the guide wire by a point connection, a line connection or a surface connection.

Preferably, when the guide wire is connected with the supports in a point connection or a line connection mode, a plurality of supports extending radially are fixed on a single guide wire; when the guide wire is connected with the supports in a surface connection mode, one or more radially extending supports are fixed on the single guide wire.

According to the invention, the section of the connection of the support to the guide wire in a direction perpendicular to the extension of the guide wire is shown as a continuous or discontinuous combination of sections.

According to the invention, the support has a length in the direction of extension of said guide wire in the range 0.1mm to 1000 mm.

According to some embodiments of the invention, the holder is integrally formed with the guidewire.

According to further embodiments of the invention, the holder is preformed and then connected to said guide wire by means of gluing or welding or mechanical connection; the preforming means includes one or more of curing, winding, braiding, cutting, etching, injection molding, casting, forging, stamping, welding, machining, assembling, extruding, etc.

Preferably, the support exhibits an outer contour which is a combination of a cylinder, polygon or simple geometric figure.

According to a preferred embodiment of the invention, as shown in fig. 4, a support, shown as an outer contour of a truncated cone and a cylinder, is fixed to the guide wire. The support is a rigid structure and is integrally formed with the guide wire. In this embodiment, the ratio of the maximum dimension of the cross-section of the support in a direction perpendicular to the guide wire to the internal diameter of the delivery tube is 0.8, the support being completely inside the lumen of the delivery tube in the delivery configuration.

According to a preferred embodiment of the invention, as shown in fig. 5, a support, shown as an outer contour of a truncated cone and a cylinder, is fixed to the guide wire. At least part of the structure of the support is deformed after being stressed, and the support is connected with the guide wire through bonding after being preformed. In this embodiment, the ratio of the maximum cross-sectional dimension of the support in a direction perpendicular to the guide wire to the inner diameter of the delivery tube is 1.5, the support has a cylindrical portion with an outer diameter smaller than that of the delivery tube and positioned in the lumen of the delivery tube, and a truncated cone portion with an outer diameter larger than that of the delivery tube and positioned outside the lumen of the delivery tube in the delivery configuration.

According to a preferred embodiment of the invention, as shown in fig. 6, a holder, which is shown as a smooth streamlined outer profile, is fixed to the guide wire. The support is a rigid structure and is connected with the guide wire through bonding after being preformed. In this embodiment, the ratio of the maximum dimension of the cross-section of the support in a direction perpendicular to the guide wire to the inner diameter of the delivery tube is 0.92, the support being entirely within the lumen of the delivery tube in the delivery configuration.

According to a preferred embodiment of the invention, as shown in fig. 7, the holder connected to the guide wire surface is formed on the guide wire by winding of a wire. In this embodiment, the ratio of the maximum dimension of the cross-section of the support in a direction perpendicular to the guide wire to the internal diameter of the delivery tube is 0.56, the support being completely inside the lumen of the delivery tube in the delivery configuration.

According to a preferred embodiment of the present invention, as shown in fig. 8, the holder secured to the guide wire is shown as a mesh weave structure. The support is made of rigid wires which are woven into a cross network structure to obtain certain elasticity and then connected with the guide wire through bonding. In this embodiment, the support has a maximum outer diameter that can be varied, the support being disposed entirely within the lumen of the delivery tube in the delivery configuration, the ratio of the maximum dimension of the cross-section taken perpendicular to the guidewire to the inner diameter of the delivery tube being 1.

According to a preferred embodiment of the present invention, as shown in FIG. 9, the holder secured to the guidewire is shown as a plurality of small radially extending posts. The support is a rigid structure and is connected with the guide wire through welding after being preformed. In this embodiment, the ratio of the maximum dimension of the cross-section of the support in a direction perpendicular to the guide wire to the internal diameter of the delivery tube is 0.9, the support being completely inside the lumen of the delivery tube in the delivery configuration.

In accordance with a preferred embodiment of the present invention, as shown in FIG. 10, the holder attached to the guidewire is shown as a plurality of rigid structures connected to the guidewire by a filamentary connection. The support is a combination of a rigid structure and a flexible structure, and is connected with the guide wire through welding after being preformed. In this embodiment, the support has a maximum outer diameter that can be varied, the support being disposed entirely within the lumen of the delivery tube in the delivery configuration, the ratio of the maximum dimension of the cross-section of the support in a direction perpendicular to the guidewire to the inner diameter of the delivery tube being 3.

According to the invention, the ratio of the axial overlap length of the holder with the endovascular implant to the axial extension length of the holder in the delivery configuration is (0.001-1): 1. Preferably, the axial overlap length of the holder with the endovascular implant covers the holder as much as possible.

According to the invention, the ratio of the axial overlap length of the support and the conveying pipe to the axial extension length of the support in the conveying configuration is (0.001-1): 1. Preferably, the holder covers the holder as much as possible of its axial overlap length with the duct. When the maximum outer diameter of the holder portion is larger than the inner diameter of the delivery tube, the holder may not be completely covered by the delivery tube.

According to the invention, the ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire is (0.01-1) to 1. The projected area of the support on the surface of the guide wire is determined by the external contour thereof.

In some preferred embodiments, the holder supports the inner wall of the endovascular implant with an outer portion or the entire portion of the endovascular implant against the inner wall of the delivery tube.

In other preferred embodiments, the holder extends through a mesh or other surface opening of the endovascular implant, and the outer profile of the holder conforms to the inner wall of the delivery tube.

In some embodiments, the holder material is one or more hard inelastic materials.

In some embodiments, the holder is made of one or more soft, resilient materials.

In some embodiments, the holder is a structure with certain elasticity formed by one or more hard inelastic materials or soft elastic materials through weaving, winding and other forming processes.

Referring to fig. 11-16, the present invention provides a retaining structure for an implant in a blood vessel, in which the holder has several outer contour shapes in a delivery configuration and a positional relationship with the delivery tube and the implant in the blood vessel. Fig. 11-16 are schematic cross-sectional views a-a of fig. 1.

In this embodiment, the holder is a rigid, inelastic material, shown in FIG. 11, in accordance with a preferred embodiment of the present invention, and is shown as circular in cross-section with an outer contour that supports the inner wall of the endovascular implant so that the endovascular implant is either partially or fully engaged against the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire is 1.

In this embodiment, the holder is a rigid inelastic material, shown in FIG. 12, in a preferred embodiment, the cross-section of which is shown as a polygon, and the outer contour of which supports the inner wall of the endovascular implant so that the outer portion or the entire portion of the endovascular implant abuts the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire is 1.

In this embodiment, the holder is a rigid inelastic material, shown in FIG. 13 in cross-section, and in this embodiment is shown as a combination of simple geometric shapes that are contoured to support the inner wall of the endovascular implant so that the endovascular implant lies laterally or entirely against the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire is 1.

In this embodiment, the holder is a rigid inelastic material, shown in FIG. 14 in cross-section, and in this embodiment is shown as a combination of simple geometric shapes that are contoured to support the inner wall of the endovascular implant so that the endovascular implant lies laterally or entirely against the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire was 0.45.

In this embodiment, shown in FIG. 15, the support is of a soft, flexible material and the support structure is capable of being deformed by a force to assume an irregular shape in the delivery configuration. The holder protrudes through a mesh or other surface opening of the endovascular implant, the outer contour of the holder lying against the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire is 1.

In this embodiment, shown in FIG. 16, the support is of a soft, flexible material and the support structure is capable of being deformed by a force to assume an irregular shape in the delivery configuration. The holder protrudes through a mesh or other surface opening of the endovascular implant, the outer contour of the holder lying against the inner wall of the delivery tube. The ratio of the area of the junction of the support and the guide wire to the projected area of the support on the surface of the guide wire was 0.88.

According to the invention, the material of the holder is one or more of a metal, an alloy or a polymer material; metals or alloys include, but are not limited to, stainless steel, platinum-tungsten alloy, platinum-iridium alloy, nickel-titanium alloy, or cobalt-chromium alloy; polymeric materials include, but are not limited to, polyethylene, polyoxymethylene, polyurethane, polyester, polytetrafluoroethylene, fluorinated ethylene propylene copolymer, polyamide, polyimide, or nylon.

An intravascular implant delivery system includes a delivery tube and a guidewire.

According to some preferred embodiments of the invention, the duct is of one-piece construction.

According to other preferred embodiments of the present invention, the delivery tube is a non-integral structure, and is a structure with an internal cavity formed by one or more of cutting, combining and weaving.

Preferably, a hypotube can be used as the delivery tube in the present invention. Further, the hypotube in this embodiment may be made of metal or polymer material, and preferably, the hypotube body is a cut metal spiral tube with a pitch gradually decreasing from the proximal end to the distal end, or a polymer material with a variable compliance; further, the metal material may be stainless steel, platinum-tungsten alloy, platinum-iridium alloy, nickel-titanium alloy or cobalt-chromium alloy, and the polymer material includes, but is not limited to, polyethylene, polyoxymethylene, polyurethane, polyester, polytetrafluoroethylene, fluorinated ethylene-propylene copolymer, polyamide, polyimide or nylon.

In accordance with the present invention, the guidewire has a visualization element 202 made of radiopaque material identifying the element location, the material comprising: gold, platinum-tungsten alloy, platinum-iridium alloy, or a developable polymer. Preferably, during the implementation of the present endovascular implant delivery system, the surgical operator can view the device's real-time position through the visualization element to determine whether the endovascular implant is in the correct position.

Referring to fig. 17-19, the present invention provides a method for securing and retaining an endovascular implant. According to this embodiment, during the initial delivery phase (fig. 17) of the endovascular implant, the guidewire remains fixed relative to the delivery tube, the holder is positioned within the head of the delivery tube and acts to hold the endovascular implant, and the holder provides pressure with its outer profile to hold the endovascular implant against the inner wall of the delivery tube, increasing the friction between the endovascular implant and the delivery tube and preventing the endovascular implant from backing out during pushing or withdrawal. In the later stage of delivery of the endovascular implant (fig. 18), relative movement of the guide wire and the delivery tube occurs, the support protruding from the head of the delivery tube, eventually reaching a release configuration (fig. 19), effecting release of the endovascular implant.

Preferably, the endovascular implant delivery system is used in conjunction with a microcatheter for endovascular implant delivery. Early in delivery, the delivery system anchors and delivers the endovascular implant down a microcatheter to near the point of release, and the microcatheter is subsequently withdrawn and further position adjusted by the delivery system until accurately positioned and released. Preferably, the selection of the micro-catheter does not affect the pushing, withdrawing and releasing actions of the implant in the blood vessel, and the implant in the blood vessel can still be driven to carry out position adjustment by the delivery system after the micro-catheter is withdrawn. Therefore, there is no clear limitation on the range of inner and outer diameters of the microcatheter used with the intravascular implant delivery system of the present invention, and many more options are available.

Preferably, the endovascular implant delivery system is applied by matching with a pushing structure, the endovascular implant pushing structure is connected with a guide wire, and the pushing, withdrawing and releasing of the endovascular implant can be realized by pushing the guide wire and changing the relative positions of the delivery pipe, the guide wire and the endovascular implant. Under the configuration of carrying, the relative position of conveyer pipe, seal wire and endovascular implant does not change, no matter be transport state or withdrawal state, endovascular implant all can not deviate from, endovascular implant can withdraw and relocate repeatedly before releasing, finally realize the accurate release of endovascular implant, improve the operation success rate by a wide margin, play the best treatment. In the release configuration, pushing the guide wire brings the position of the support and the delivery pipe to change, the support extends out of the head of the delivery pipe, and release of the endovascular implant is achieved.

According to the endovascular implant delivery system provided by the preferred embodiment, when the endovascular implant is in an unreleased state, the endovascular implant delivery system maintains the stability and flexibility of the system, and can be operated by the existing medical technical means; compared with a conveying device which conveys the implant in the blood vessel after the assembly and the implant in the blood vessel are physically connected, the implant in the blood vessel and the conveying system are tightly fixed through the support and the conveying pipe, the implant in the blood vessel is not easy to fall off, and conveying force can be more effectively transmitted. The intravascular implant delivery system can also realize accurate positioning of intravascular implant release, control the guide wire to position the intravascular implant to the release position, and accurately release the intravascular implant after the microcatheter is withdrawn; the position of the implant in the blood vessel can be still adjusted before the release until the release position of the implant in the blood vessel is determined to be accurate, so that the maximum success rate can be ensured.

In the description of the present application, it is to be understood that the positional or positional relationships indicated by the directional terms such as "proximal", distal, front, rear ", etc., are generally based on the positional or positional relationships shown in the drawings for the convenience of description and simplicity of description, and that, unless otherwise stated, these directional terms are not intended to indicate and imply that the referenced device or element must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be considered as limiting the scope of the present application; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

The above embodiments are merely preferred embodiments of the present invention, which are not intended to limit the scope of the present invention, and various changes may be made in the above embodiments of the present invention. All simple and equivalent changes and modifications made according to the claims and the content of the specification of the present application fall within the scope of the claims of the present patent application. The invention has not been described in detail in order to avoid obscuring the invention.