阅读说明：本技术 动力传递组件及血泵 (Power transmission assembly and blood pump ) 是由 张家良 托马斯·乔治·罗根 于 2021-10-22 设计创作，主要内容包括：公开一种血泵的动力传递组件,包括导管和用于带动血泵的叶轮旋转的驱动轴。驱动轴内设有内流道,驱动轴和导管之间形成外流道。外流道在导管的远端设有第一排出口,内流道在驱动轴的远端设有第二排出口。内、外流道中的一个与灌注液输入部连通,驱动轴壁上设有将内、外流道连通的连通部,灌注液输入部将灌注液输入内、外流道中的一个,两个流道中另一个通过连通部输入灌注液。通过构建共同向远端输送灌注液的内、外,实现灌注液体的多通道输送,灌注液可对轴承起到润滑作用,并可避免血液进入轴承而遭受破坏。(A power transfer assembly for a blood pump is disclosed, including a conduit and a drive shaft for driving rotation of an impeller of the blood pump. An inner flow passage is arranged in the driving shaft, and an outer flow passage is formed between the driving shaft and the guide pipe. The outer flow passage is provided with a first discharge port at the distal end of the catheter, and the inner flow passage is provided with a second discharge port at the distal end of the drive shaft. One of the inner and outer flow channels is communicated with the perfusate input part, the wall of the driving shaft is provided with a communicating part which communicates the inner and outer flow channels, the perfusate input part inputs the perfusate into one of the inner and outer flow channels, and the other of the two flow channels inputs the perfusate through the communicating part. The infusion liquid is conveyed to the far end through the inside and the outside of the far end, so that the multi-channel conveying of the infusion liquid is realized, the infusion liquid can lubricate the bearing, and the blood can be prevented from entering the bearing and being damaged.)

1. A blood pump, comprising:

a drive assembly;

a catheter having a proximal end connected to the drive assembly;

the driving shaft is rotatably arranged in the guide pipe in a penetrating way;

a pump assembly, deliverable through the conduit to a desired location of the heart, comprising a pump housing having an inlet end and an outlet end, an impeller housed within the pump housing; the impeller is driven to rotate by the drive shaft to suck blood into the pump housing from the inlet end and discharge the blood from the outlet end; the pump shell comprises a bracket and a covering film which partially covers the bracket; the proximal end of the stent is connected to the catheter distal end;

an outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft; the far end of the outer flow passage is provided with a first discharge port positioned at the near end of the bracket, and the far end of the inner flow passage is provided with a second discharge port positioned at the far end of the bracket;

when the blood pump is in a working state that the impeller rotates, perfusate in the outer flow channel and the inner and outer flow channels is discharged from the near end and the far end of the bracket through the first discharge port and the second discharge port respectively, and the impeller is limited between the first discharge port and the second discharge port.

2. The blood pump of claim 1, wherein the impeller is provided with a bearing mount on a proximal side and a distal bearing chamber on a distal side; a near-end bearing is arranged in the bearing mounting part, and a far-end bearing is arranged in the far-end bearing chamber; and the perfusate of the outer flow passage is discharged through the near-end bearing, and the perfusate of the inner flow passage is discharged through the far-end bearing.

3. The blood pump of claim 2, wherein the bearing mount is a proximal bearing chamber; alternatively, the bearing mount is constituted by a distal portion of the catheter; alternatively, the bearing mount is constituted by a proximal end portion of the bracket.

4. The blood pump of claim 2, wherein the first exhaust port is located distal to the proximal bearing;

preferably, the second discharge port is located within the distal bearing chamber and distal to the distal bearing.

5. The blood pump of claim 2 in which the proximal bearing comprises first and second spaced proximal bearings, the outer wall of the drive shaft being provided with a stop between the first and second proximal bearings; preferably, a flow gap is formed between the stopper outer wall and the bearing mounting portion inner wall.

6. The blood pump of claim 1, wherein perfusate pressure within said first exhaust is greater than blood pressure proximate said first exhaust and perfusate pressure within said second exhaust is greater than blood pressure proximate said second exhaust.

7. The blood pump of claim 1, wherein the drive shaft comprises a first shaft and a second shaft having a stiffness greater than a stiffness of the first shaft; the proximal end of the first shaft is connected with the driving assembly, and the distal end of the first shaft is connected with the proximal end of the second shaft; the second shaft is connected with the impeller.

8. The blood pump of claim 7, wherein the first shaft is a braided structure with walls that are liquid permeable, forming braided slits communicating the inner and outer flow passages;

preferably, the first shaft includes a plurality of braided layers sleeved layer by layer, the spiral direction of two adjacent braided layers is opposite, and the spiral direction of the braided layer located at the outermost layer is opposite to the rotation direction of the first shaft.

9. The blood pump of claim 7, wherein the location of the connection of the stent to the catheter is proximal to the second shaft; preferably, the proximal end of the bracket is provided with a connecting secondary tube connected with the distal end of the catheter, and the proximal end of the second shaft does not extend out of the connecting secondary tube.

10. A blood pump, comprising:

a drive assembly;

a catheter having a proximal end connected to the drive assembly;

the driving shaft is rotatably arranged in the guide pipe in a penetrating way;

a pump assembly deliverable through the conduit to a desired location of the heart, including a pump housing having an inlet end and an outlet end, an impeller received within the pump housing, the impeller being driven in rotation by the drive shaft to draw blood into the pump housing from the inlet end and to discharge blood from the outlet end; the pump shell comprises a bracket connected with the far end of the catheter and a covering film partially covering the bracket;

the far-end bearing chamber is connected to the far end of the bracket and internally provided with a far-end bearing; a distal end of the drive shaft extends through the distal bearing;

wherein the drive shaft has a hollow interior communicating with the distal bearing chamber, a closure being disposed within the distal bearing chamber, the closure being located distally of the distal end of the drive shaft.

11. The blood pump of claim 10, wherein said closure is provided with a resealable passage for a guide wire to pass through, said resealable passage being closed upon removal of said guide wire;

preferably, the distal end of the distal bearing chamber is provided with an atraumatic support, and the blocking piece is arranged on the near side of the atraumatic support.

12. A power transfer assembly for a blood pump comprising:

a conduit;

the driving shaft is used for driving the impeller of the blood pump to rotate and is rotatably arranged in the guide pipe in a penetrating way; the proximal end of the drive shaft penetrates out of the proximal end of the catheter to be connected with the drive assembly, and the distal end of the drive shaft penetrates out of the distal end of the catheter to be connected with the impeller;

an outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft;

the wall of the driving shaft is provided with a communicating part which communicates the inner flow passage with the outer flow passage;

one of the inner flow channel and the outer flow channel is communicated with a perfusate input part, the perfusate input part inputs perfusate into one of the inner flow channel and the outer flow channel, and the other of the inner flow channel and the outer flow channel is input with perfusate through the communicating part.

13. A power transmission assembly of a blood pump, the blood pump comprising a pump housing, an impeller housed in the pump housing; the power transmission assembly includes:

a catheter having a proximal end for connection to a drive assembly and a distal end for connection to the pump housing;

the driving shaft is rotatably arranged in the guide pipe in a penetrating way; the proximal end of the drive shaft penetrates out of the proximal end of the catheter to be driven to rotate by the drive assembly, and the distal end of the drive shaft penetrates out of the distal end of the catheter to be connected with the impeller;

an outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft; the far end of the outer flow passage is provided with a first discharge port positioned near the impeller, and the far end of the inner flow passage is provided with a second discharge port positioned far from the impeller; the perfusate in the outer runner is discharged through the first discharge port, and the perfusate in the inner runner is discharged through the second discharge port.

14. The power transmission assembly as claimed in claim 12 or 13, wherein a communicating portion that communicates the inner flow passage and the outer flow passage is provided on a wall of the drive shaft, the communicating portion communicating the inner flow passage and the outer flow passage in a liquid-permeable manner;

preferably, the communication comprises at least part of the length of the wall of the drive shaft within the conduit that is permeable to liquid; alternatively, the wall of the drive shaft at least partially within the conduit is of a liquid permeable construction.

Technical Field

The invention relates to the field of medical equipment, in particular to a power transmission assembly of a catheter pump for heart assistance, and more particularly to a blood pump, a power transmission assembly and a foldable bracket.

Background

The prior known catheter pumps fall into two categories: one type is a built-in motor type, a motor connecting shaft directly drives an impeller, and the motor enters a human body along with a conduit; the other type is an external motor type, the impeller is driven by the flexible shaft, and the motor does not enter the human body along with the conduit and the impeller.

The flexible shaft of the external motor type is arranged in the inner cavity of the catheter and is guided and limited by the catheter. To reduce wear between the flexible shaft and the catheter lumen, to reduce vibration caused by high speed rotation of the flexible shaft, and to reduce heat generation caused by wear, a physiological fluid, such as a physiological saline or glucose solution, is often poured between the flexible shaft and the catheter.

Besides the above functions, the perfused liquid can also prevent the pump from driving blood to enter the bearing in the high-speed rotation process, thereby realizing the sealing function.

The prior art priming (purge) method is to provide a joint at the proximal end of the drive, connect the priming device, and allow the fluid to flow from the proximal end to the distal end, and finally enter the body, and further require a contact-type dynamic sealing device, such as a flood seal, at the proximal end of the joint.

A disadvantage of the prior art is that a large amount of perfusion liquid entering the patient may have a health-related adverse effect on the patient, since some abrasive particles may be entrained in the perfusion liquid; in addition, the contact dynamic seal fails due to long-term wear.

Moreover, if the perfusion liquid enters the body at a larger perfusion pressure, adverse reaction of a patient is easy to cause, and uncontrollable adverse effects are generated, so that the perfusion liquid is more expectedly required to enter the body at a lower pressure, and the adverse reaction of the human body is reduced.

In addition, the interventional pump assembly of the catheter pump needs excellent folding performance so as to be capable of stably keeping the shape of the pump shell after being unfolded, and the pump effect is prevented from being adversely affected due to the fact that the pump shell cannot stably keep the shape.

In addition, the pump assembly of the catheter pump needs to be folded into the sheath before being inserted into the body and unfolded at a desired position in the body, and the sheath needs to be retracted again when being removed from the body, but the current stent design has larger resistance when the sheath is retracted, so that the resistance is easy to meet, and the difficulty of removal is increased.

Disclosure of Invention

It is an object of the present invention to provide a blood pump and a power transmission assembly therefor that reduces the risk of perfusion liquid entering the patient.

It is a further object of the present invention to provide a blood pump and power transfer assembly thereof that reduces perfusion pressure and the risk of large perfusion pressures.

In order to achieve at least one of the above purposes, the invention adopts the following technical scheme:

a power transfer assembly for a blood pump comprising: the device comprises a driving shaft for driving an impeller of the blood pump to rotate, a first flow passage for perfusion fluid to flow, and a coupling body provided with an axial passage communicated with the first flow passage. The drive shaft passes through the axial passage to be connected with the drive assembly, and the coupling body is provided with an output interface which is communicated with the axial passage and is used for outputting the perfusion fluid in the first flow passage outwards. A supporting body which is sleeved outside the driving shaft and is positioned at the upstream of the output interface along the power transmission direction is arranged in the axial channel, and a rotating gap is formed between the supporting body and the driving shaft. The outer wall of the driving shaft is provided with a spiral structure, and at least part of the spiral structure is sleeved in the supporting body.

Through the helical structure that sets up the rotation direction opposite of spiral extending direction and drive shaft, at the rotatory in-process of drive shaft, helical structure can produce the thrust along power transmission direction to the liquid in the turning clearance, borrows this and prevents the liquid of backward flow to drive assembly through the turning clearance, and inside the liquid of effectively guaranteeing the refluence can not enter into drive assembly, promoted structural reliability, prolonged the life of product.

Moreover, through setting up this helical structure, form non-contact sealed between drive shaft and the coupling body, the wearing and tearing influence that produces when can reducing rotatory promotes the structural reliability, increase of service life.

The spiral structure has a direction of rotation opposite to the direction of rotation of the drive shaft. Viewed from the proximal end to the distal end, the helix is left-handed when the rotation of the drive shaft is clockwise, or right-handed when the rotation of the drive shaft is counterclockwise.

The drive shaft includes a connecting shaft in the axial passage and a first shaft connected to the connecting shaft, the first shaft having a proximal end connected to the connected shaft and a distal end for positioning the impeller.

The helical structure is a helical groove or a thread provided on the outer wall of the connecting shaft.

Part of the helical structure is located in the support body, and part of the helical structure is located outside the support body.

The spiral structure extends spirally downstream of the output interface in the power transmission direction.

A second flow passage is also provided for the flow of perfusion fluid, the second flow passage having an input for the input of perfusion fluid adjacent the proximal end and an output for the output of perfusion fluid adjacent the distal end. The first flow passage has an output end in communication with the output interface and an input end adjacent the distal end for inputting perfusion fluid. The output part of the second flow passage is communicated with the input end of the first flow passage, and the coupling body is provided with an input interface communicated with the input part of the second flow passage.

The first shaft is sleeved with a guide pipe. The first flow passage is positioned between the outer wall of the first shaft and the inner wall of the conduit, and the second flow passage is positioned in the conduit wall of the conduit and penetrates through the conduit wall of the conduit along the axial direction.

The second flow passage is communicated with an output gap of the ring sleeve outside the first shaft, and an outlet of the output gap is communicated with a pump cavity of the blood pump for accommodating the impeller, or the outlet of the output gap faces to the power transmission direction of the first shaft.

The pipe has and is responsible for the body and locate the main preceding protruding exit tube of body front end, is responsible for and has preceding step between the body and the preceding protruding exit tube, and the input part is the input port that is located on preceding step. The axial channel has a first channel section into which the nose tube extends, and a second channel section into which the main tube body extends. The outer wall of the front protruding pipe is in sealing connection with the inner wall of the first channel section, and the outer wall of the end part of the main pipe is in sealing connection with the inner wall of the second channel section. The output interface is communicated with the first channel section, and the input interface is communicated with the second channel section.

The support body comprises a first bearing sleeved outside the connecting shaft, and the output interface is positioned at the far side of the first bearing.

The first shaft outer sleeve is provided with axially spaced second and third bearings, the third bearing being located distally of the second bearing. An interval annulus communicated with the output part of the second flow passage is formed between the second bearing and the third bearing, an output gap for communicating the interval annulus with the outside of the conduit is formed between the third bearing and the first shaft, and a communication gap for communicating the input end of the first flow passage with the interval annulus is formed between the second bearing and the first shaft.

The guide pipe is provided with a rear protruding pipe arranged at the rear end of the main pipe body, and a bearing seat sleeve is sleeved on the rear protruding pipe. The bearing sleeve is externally provided with a fixed sleeve, and the second bearing and the third bearing are fixed in the bearing sleeve at intervals.

A power transfer assembly for a blood pump comprising: the pipe, rotationally wear to locate in the pipe and be used for driving the rotatory drive shaft of the impeller of blood pump. The proximal end of the drive shaft extends out of the proximal end of the catheter to connect to the drive assembly and the distal end extends out of the distal end of the catheter to connect to the impeller. An outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft. The wall of the driving shaft is provided with a communicating part which communicates the inner flow passage and the outer flow passage, one of the inner flow passage and the outer flow passage is communicated with a perfusate input part, the perfusate input part inputs perfusate into one of the inner flow passage and the outer flow passage, and the other of the inner flow passage and the outer flow passage inputs perfusate through the communicating part.

Through constructing the interior, outer runner of carrying the perfusate to the distal end jointly, realize the multichannel of perfusate and carry to perfusate input portion and outer runner and interior runner in a intercommunication, can simplify the input structure, be convenient for make, through the flow area of intercommunication portion increase perfusate when inputing into one of them runner, reduce the filling pressure, avoid because of the too big harmful effects that produce of filling pressure, and can guarantee the flow of filling again, the guarantee intervenes the normal smooth going on of operation.

The far end of the outer flow passage is provided with a first discharge port located near the impeller, and the far end of the inner flow passage is provided with a second discharge port located far from the impeller. The perfusate in the outer and inner flow channels is discharged through the first and second discharge ports, respectively.

A power transmission assembly of a blood pump comprises a pump shell and an impeller accommodated in the pump shell. The power transmission assembly includes a conduit and a drive shaft rotatably disposed through the conduit. The proximal end of the catheter is used for connecting the driving assembly, and the distal end of the catheter is used for connecting the pump shell. The proximal end of the drive shaft extends out of the proximal end of the catheter for rotation by the drive assembly and the distal end extends out of the distal end of the catheter for connection to the impeller. An outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft. The far end of the outer flow passage is provided with a first discharge port located near the impeller, and the far end of the inner flow passage is provided with a second discharge port located far from the impeller. The perfusate in the outer flow channel is discharged through the first discharge port, and the perfusate in the inner flow channel is discharged through the second discharge port. The second exhaust port is located within the distal bearing chamber and distal to the distal bearing.

Through constructing the outer runner and the inner runner which convey the perfusate to the far end together, the perfusate can lubricate the near-end bearing and the far-end bearing, and can avoid blood from entering the bearing to be damaged, thereby preventing hemolysis.

The power transmission assembly is also provided with a perfusate input part which is communicated with at least one of the inner flow passage and the outer flow passage. Preferably, the perfusate input part is communicated with the outer flow passage, a communicating part for communicating the inner flow passage with the outer flow passage is arranged on the wall of the driving shaft, and the perfusate in the outer flow passage is input into the inner flow passage through the communicating part.

The communicating portion communicates the inner flow path and the outer flow path in a liquid-permeable manner, including a wall of the drive shaft of at least a partial length permeable to liquid in the conduit. Alternatively, at least part of the wall of the drive shaft within the conduit is of a liquid permeable construction to form the communication.

The proximal end of the catheter is in communication with the perfusate input to communicate the proximal end of the outer flow channel with the perfusate input. The near-end connection coupling body of pipe, the drive shaft passes through the coupling body to be connected with drive assembly, and the perfusate input is located on the coupling body.

A blood pump, comprising: the system includes a drive assembly, a catheter having a proximal end connected to the drive assembly, a drive shaft rotatably disposed within the catheter, and a pump assembly that can pump blood through the catheter to a desired location of the heart. The pump assembly includes a pump housing having an inlet end and an outlet end, an impeller housed within the pump housing, the impeller being driven in rotation by a drive shaft to draw blood into the pump housing from the inlet end and expel the blood from the outlet end. The pump housing includes a stent, a proximal end of which is connected to the distal end of the catheter, and a cover that partially covers the stent. An outer flow passage is formed between the driving shaft and the guide pipe, and an inner flow passage is formed in the driving shaft. The far end of outer runner is equipped with the first discharge port that is located the support near-end, and the distal end of interior runner is equipped with the second discharge port that is located the support distal end.

When the blood pump is in a working state of rotating the impeller, perfusate in the outer flow passage and the inner and outer flow passages is discharged from the near end and the far end of the bracket through the first and the second discharge ports respectively, and the impeller is limited between the first and the second discharge ports.

Perfusate in the interior, outer runner flows out at the distal end and the near-end of impeller respectively, forms liquid high-pressure region at catheter distal end and distal end bearing chamber near-end, and then prevents that blood from getting into in catheter distal end and the distal end bearing chamber, prevents to form the thrombus.

The impeller nearside is equipped with the bearing installation department, and the impeller distal side is equipped with distal end bearing chamber. The bearing mount is a proximal bearing chamber. Alternatively, the bearing mount is constituted by a distal portion of the catheter. Alternatively, the bearing mount is formed by a proximal portion of the bracket. The bearing mounting part and the far-end bearing chamber are respectively provided with a near-end bearing and a far-end bearing for supporting the driving shaft to rotate; and perfusate of the outer flow passage and the inner flow passage respectively flows through the proximal bearing and the distal bearing to be discharged.

The first discharge port is located distal to the proximal bearing. The second discharge port is located the distal end bearing room, constitutes the perfusate discharge port between the distal end outer wall of the proximal end inner wall of distal end bearing room and drive shaft. The far end of the driving shaft is internally provided with a diffuser section, and the flow area of the diffuser section is gradually enlarged along the internal flow direction of the diffuser section. The second discharge port is a distal port of the diffuser section.

The proximal bearing includes first and second proximal bearings spaced apart, and the outer wall of the drive shaft is provided with a stop between the first and second proximal bearings. A flow gap is formed between the outer wall of the stopper and the inner wall of the bearing mounting portion.

The perfusate pressure in the first drain is greater than the blood pressure near the first drain, and the perfusate pressure in the second drain is greater than the blood pressure near the second drain.

The drive shaft includes a first shaft and a second shaft having a stiffness greater than a stiffness of the first shaft. The proximal end of the first shaft is connected to the drive assembly and the distal end is connected to the proximal end of the second shaft. The second shaft is connected with the impeller.

The wall of the first shaft is provided with a communicating part which communicates the inner flow passage and the outer flow passage, and the communicating part extends from the near end to the far end of the first shaft. The first shaft is of a braided construction, the walls of which are liquid permeable, and the communication portions are braided slits extending through the wall of the first shaft. The primary shaft comprises a plurality of woven layers sleeved layer by layer, the spiral directions of two adjacent woven layers are opposite, and the spiral direction of the woven layer positioned on the outermost layer is opposite to the rotating direction of the primary shaft.

The location of attachment of the stent to the catheter is proximal to the second axis. The near end of the bracket is provided with a connecting secondary tube connected with the far end of the catheter, and the near end of the second shaft does not extend out of the connecting secondary tube.

A blood pump, comprising: the system includes a drive assembly, a catheter having a proximal end connected to the drive assembly, a drive shaft rotatably disposed within the catheter, and a pump assembly that can pump blood through the catheter to a desired location of the heart. The pump assembly includes a pump housing having an inlet end and an outlet end, an impeller housed within the pump housing, the impeller being driven in rotation by a drive shaft to draw blood into the pump housing from the inlet end and expel the blood from the outlet end. The pump housing includes a stent, a proximal end of which is connected to the distal end of the catheter, and a cover that partially covers the stent. The distal end of the support frame is connected to a distal bearing chamber having a distal bearing disposed therein, the distal end of the drive shaft extending through the distal bearing. The drive shaft has the cavity inner chamber with distal end bearing chamber intercommunication, is equipped with the shutoff piece of the shutoff of position in the distal end bearing chamber, and the shutoff piece is located the distal side of drive shaft distal end.

Rotation of the impeller causes blood to be drawn into the pump housing from the inlet end at the distal end, with the distal bearing chamber being closer to the inlet end of the pump housing. The existence of shutoff piece for the perfusate that the hollow inner chamber of drive shaft was carried can't continue to flow forward, and can only be compelled to redirect the backward flow, flows out from distal end bearing chamber, effectively avoids the blood that is inhaled the pump case through the entrance point to get into the possibility of distal end bearing chamber, and the cell in the protection blood is not rolled by distal end bearing and is destroyed, avoids the hemolysis.

The closure is provided with a resealable passage for the guidewire to pass through, the resealable passage being closed upon removal of the guidewire.

The far end of the far end bearing chamber is provided with a non-invasive supporting piece, the non-invasive supporting piece is provided with a hollow tube cavity communicated with the far end bearing chamber, and the blocking piece is arranged on the near side of the non-invasive supporting piece. The near end of the noninvasive support piece is located in the far-end bearing chamber, a step is arranged in the far-end bearing chamber, and the blocking piece is clamped and fixed between the step and the near end of the noninvasive support piece.

Drawings

FIG. 1 is a schematic illustration of a blood pump configuration according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of the proximal portion of FIG. 1;

FIG. 3 is a schematic view of the distal portion of FIG. 1;

FIG. 4 is a schematic structural view of the coupling body and the connecting shaft shown in FIG. 2;

FIG. 5 is a schematic flow diagram of the perfusion fluid of FIG. 2;

FIG. 6 is a schematic view of the helix structure of FIG. 2;

FIG. 7 is a schematic flow diagram of the perfusion fluid flow direction at the forward end of the catheter of FIG. 2;

FIG. 8 is a side view of a catheter;

FIG. 9 is a schematic view of a portion of the structure of FIG. 3;

FIG. 10 is an enlarged view of a portion of FIG. 9;

FIG. 11 is a schematic view of the foldable stand of FIG. 1;

FIG. 12 is an enlarged view of a portion of FIG. 11;

FIG. 13 is a schematic structural view of one half of a foldable stand provided in accordance with another embodiment of the present invention;

FIG. 14 is a schematic view of a blood pump according to another embodiment of the present invention;

FIG. 15 is a schematic view of the main interventional part of FIG. 14;

FIG. 16 is an enlarged view of the distal portion (bearing mount) of the catheter of FIG. 15;

FIG. 17 is an enlarged view of the distal portion (distal bearing chamber) of the second shaft of FIG. 15;

FIG. 18 is a schematic diagram of a portion of a pump assembly of a blood pump provided in accordance with another embodiment of the present invention;

FIG. 19 is an enlarged view of the distal portion (bearing mount) of the catheter of FIG. 18;

FIG. 20 is an enlarged view of the distal portion of the second shaft (distal bearing chamber) of FIG. 18;

fig. 21 is a schematic view of the inner and outer flow channels of fig. 18 illustrating osmotic flow of fluid.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

It will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terms "proximal", "distal" and "anterior", "posterior" are used herein with respect to a clinician operating a blood pump. The terms "proximal" and "posterior" refer to portions that are relatively close to the clinician, and the terms "distal" and "anterior" refer to portions that are relatively far from the clinician. For example, the extracorporeal portion is proximal or posterior and the interventional intracorporeal portion is distal or anterior.

Referring to fig. 1 to 10, the blood pump according to the embodiment of the present invention has a power transmission assembly for transmitting power to an impeller 410 of the blood pump to drive the impeller 410 to pump blood. The power transmission assembly includes a driving shaft for driving the impeller 410 to rotate, and both ends of the driving shaft respectively penetrate through both ends of the guide tube 300 to be respectively connected to the driving assembly 100 and the impeller 410.

The drive shaft includes a first shaft 350, the first shaft 350 being a flexible shaft or axle, having a proximal end coupled to the drive assembly 100 for power input and a distal end coupled to a second shaft 355. The second shaft 355 is connected to the impeller 410 to rotate the impeller 410. The drive assembly 100 utilizes a first shaft 350 and a second shaft 355 to transmit power to the impeller 410.

To avoid contact of the rotating first shaft 350 with the blood vessel, a catheter 300 is sheathed around the first shaft 350. The catheter 300 is a flexible catheter that is bendable along with the first shaft 350 to accommodate the bent configuration of the human vasculature.

As shown in fig. 2, the driving assembly 100 includes a motor 101 and a motor case 102 housing the motor 101. The output end of the motor 101 is connected to the proximal end of the first shaft 350 through the connecting shaft 220, and the connecting shaft 220 transmits the power output by the motor 101 to the first shaft 350, and then to the impeller 410 through the second shaft 355.

In this embodiment, the "far-near" position may be defined by a positional relationship with respect to the drive assembly 100, and the power transmission direction F along the drive assembly 100 to the impeller 410 may also be regarded as being transmitted from the near to the far. Accordingly, the proximal end of the first shaft 350 is closer to the drive assembly 100 than the distal end thereof, although the distal and proximal ends of the other components are likewise defined herein.

The drive assembly 100 and the catheter 300 are connected by a coupling body 200, and the drive shaft is connected to the motor 101 by the coupling body 200. The coupling body 200 may be any suitable conventional structure, such as a magnetic coupling structure, to realize the transmission connection between the driving shaft and the motor 101, which is not limited in this embodiment.

As shown in fig. 4 and 5, the coupling body 200 is provided with an axial passage 210, and the driving shaft is connected to the motor 101 through the axial passage 210. The axial passage 210 is a linear passage that receives the coupling shaft 220 therein, and the proximal end of the first shaft 350 extends from the distal end port of the axial passage 210 into which it is coupled to the distal end of the coupling shaft 220.

The proximal end of the catheter 300 extends into the axial passage 210 and is fixedly and sealingly attached to the inner wall of the axial passage 210. Specifically, the outer wall 301 of the proximal end of the catheter 300 is hermetically bonded to the coupling body 200, so as to achieve a fixed connection therebetween.

As shown in fig. 5 to 10, the power transmission assembly is provided with a first flow passage 700 for communicating the perfusion fluid. The perfusion fluid can cool the drive shaft, avoid rotating overheating, and can also lubricate the rotation of the drive shaft. The first flow channel 700 has an output end adjacent the proximal end of the first shaft 350 for outputting the perfusion fluid, and an input end adjacent the distal end of the first shaft 350 for inputting the perfusion fluid. In the first flow channel 700, the flow direction of the perfusion fluid is from the distal end to the proximal end. By expelling the irrigation fluid outwardly from the output end adjacent the proximal end of the first shaft 350, the irrigation fluid is prevented from entering the body.

The output end of the first flow channel 700 for outputting the perfusion fluid outwards is adjacent to the proximal end of the first shaft 350, but not arranged at the distal end into the body, so that the perfusion fluid can be prevented from being input into the body, and the risk of abrasion particles entering the body can be reduced.

As shown in fig. 5 and 7, the first flow channel 700 extends along with the first shaft 350, and the flow directions of the fluids inside the two channels are opposite. The first flow channel 700 is looped around the first shaft 350, and the outer wall of the first shaft 350 forms the channel wall of the first flow channel 700. Specifically, the first flow channel 700 is located between the conduit 300 and the first shaft 350. The inner wall 302 of the guide tube 300 and the outer wall of the first shaft 350 constitute a flow channel wall of the first flow channel 700, and the first flow channel 700 has a circular cross-section.

The power transmission assembly is further provided with a second flow channel 600 for the flow of priming fluid, the second flow channel 600 likewise being able to cool the first shaft 350. The second flow channel 600 is used to convey perfusion fluid (e.g., cooling fluid, etc.). Further, the second flow channel 600 is used for conveying the perfusion fluid from the proximal end to the distal end.

The second flow channel 600 has an input for inputting perfusion fluid adjacent the proximal end and an output for outputting perfusion fluid adjacent the distal end. The output portion of the second flow channel 600 communicates with the input end of the first flow channel 700.

The first flow channel 700 and the second flow channel 600 are arranged outside the first shaft 350 in a parallel manner, the outer wall of the first shaft 350 forms a channel wall of the first flow channel 700 or a channel wall of the second flow channel 600, and the extending direction of the first flow channel 700 and/or the second flow channel 600 is parallel to the axial direction of the first shaft 350.

As shown in fig. 7 and 8, the second flow channel 600 is located between the outer wall 301 and the inner wall 302 of the conduit 300. The first flow channel 700 is located inside the inner wall 302 of the catheter 300, specifically between the outer wall of the first shaft 350 and the inner wall 302 of the catheter 300, and the second flow channel 600 is located inside the wall of the catheter 300 to axially penetrate the wall of the catheter 300.

The first flow channel 700 is used as a fluid return channel to convey abrasive dust generated in the power transmission process to the outside of the body, so that the risk of entering the body is reduced. As shown in FIG. 8, catheter 300 is a multi-lumen tube. The center of the catheter 300 has a main lumen that houses the first shaft 350. The pipe wall of the conduit 300 is provided with a plurality of cavities 601 and 602 forming the second flow channel 600, so as to improve the flow capacity of the second flow channel 600, and further improve the cooling capacity.

As shown in fig. 9 and 10, in order to prevent blood from flowing back with the perfusion fluid, the power transmission assembly is further provided with an output gap 335, and the output gap 335 is sleeved outside the driving shaft and communicated with the second flow channel 600. The output gap 335 is located downstream of the first flow passage 700 in the power transmission direction F between the conduit 300 and the drive shaft. The outlet of the output gap 335 opens into the pump chamber of the blood pump housing impeller 410, thereby preventing blood flowing into the pump chamber from entering the conduit 300.

The outlet of the output gap 335 faces in the power transfer direction F of the first shaft 350 (i.e., faces parallel to the power transfer direction F). By providing the outlet gap 335, body fluids such as blood can be prevented from entering the first flow channel 700 and flowing back with the perfusion fluid. And, the perfusion fluid flows into between bearing and drive shaft through output clearance 335, reduces the wearing and tearing between drive shaft and the bearing, promotes life.

As shown in fig. 4 and 5, the coupling body 200 is provided with an output port 202 communicating with an output end of the first flow channel 700, and an input port 201 communicating with an input portion of the second flow channel 600. The input interface 201 and the output interface 202 are axially spaced, with the output interface 202 being closer to the drive assembly 100 than the input interface 201.

As shown in fig. 6, a shaft gap 215 is formed between the connecting shaft 220 and the inner wall of the coupling body 200, the output port 202 opens into the shaft gap 215, and the shaft gap 215 communicates with the output end (port) of the first flow channel 700.

To facilitate connection to coupling body 200 and to avoid fluid leakage, the proximal end of catheter 300 is stepped. As shown in fig. 7, the catheter 300 includes a main tube 311 and a front protruding tube 312 provided at the rear end of the main tube 311, a front step 315 is provided between the main tube 311 and the front protruding tube 312, and the input portion is an input port (input port) located on the front step 315. Axial channel 210 has a first channel section 211, into which a front protruding tube 312 protrudes, and a second channel section 212, into which a main tube body 311 protrudes. The first channel section 211 is located at the front side of the second channel section 212, closer to the connecting shaft 220 or the drive assembly 100.

The outer wall of the front protruding pipe 312 is connected with the inner wall of the first channel section 211 in a sealing manner, and the outer wall 301 of the end of the main pipe body 311 is connected with the inner wall of the second channel section 212 in a sealing manner. The output interface 202 opens into a first channel section 211 and the input interface 201 opens into a second channel section 212.

As shown in fig. 4, the axial passage 210 is a stepped hole having a shaft passage section at a rear side of the first passage section 211, the shaft passage section having an inner diameter smaller than that of the first passage section 211. Accordingly, the inner diameters of the shaft passage section, the first passage section 211, and the second passage section 212 in the power transmission direction F are increased in order, and corresponding steps are formed. The shaft channel section, the first channel section 211, and the second channel section 212 are all cylindrical channels. The step between the shaft channel section and the first channel section 211 is a limiting step, the front protruding pipe 312 extends into the axial channel 210, and the end face of the front protruding pipe 312 contacts with the limiting step to be axially limited. The outer tube wall of the front protruding tube 312 is hermetically bonded to the inner channel wall of the first channel section 211.

The step between the first channel section 211 and the second channel section 212 is a communication step 213, the front step 315 and the communication step 213 between the main tube 311 and the front protruding tube 312 are oppositely arranged at intervals, an interval communication annulus is formed between the main tube and the front protruding tube, and the interval communication annulus connects the input interface 201 on the coupling body 200 with the first channel 700 on the front step 315. The outer wall surface of the rear end of the main pipe body 311 is sealingly bonded to the passage inner wall of the second passage section 212 (the portion located downstream of the input port 201 in the power transmission direction F).

As shown in fig. 4 to 6, a supporting body 230 is disposed in the axial passage 210 and sleeved outside the connecting shaft 220, the supporting body 230 is located upstream of the output interface 202, a rotating gap 231 is provided between the supporting body 230 and the driving shaft, and a radial gap width of the rotating gap 231 is smaller than a radial gap width of the shaft gap 215. The supporting body 230 is a first bearing fixed in the coupling body 200 and sleeved outside the connecting shaft 220, and the rotating gap 231 is located between the first bearing and the connecting shaft 220.

The outer wall of the driving shaft is provided with a spiral structure 221, the rotating direction of the spiral structure 221 is opposite to the rotating direction of the driving shaft, and at least part of the spiral structure 221 is sleeved in the supporting body 230.

In the embodiment shown in fig. 6, the helical structure 221 is provided on the outer wall of the connection shaft 220. The helical structure 221 is a left-handed thread in the case where the drive shaft rotates clockwise as viewed from the drive end (drive assembly 100) in the power transmission direction F. Alternatively, in the case where the drive shaft rotates counterclockwise, the helical structure 221 is a right-handed thread.

Through the helical structure 221 that sets up the rotation direction opposite of spiral extending direction and drive shaft, at the rotatory in-process of drive shaft, helical structure 221 can produce the thrust along power transmission direction F to the liquid in running clearance 231, and the liquid that stops the backward flow through running clearance 231 flow direction drive assembly 100 borrows this, and inside the liquid that has effectively guaranteed the refluence can not enter into drive assembly 100, has promoted structural reliability, has prolonged the life of product.

Moreover, by arranging the spiral structure 221, non-contact sealing is formed between the driving shaft and the coupling body 200, so that the abrasion influence generated during rotation can be reduced, the structural reliability is improved, and the service life is prolonged.

In the present embodiment, the spiral structure 221 may be a spiral groove 222 or a thread provided on an outer wall of the connection shaft 220. The output interface 202 is located on the downstream side of the first bearing in the power transmission direction F. Specifically, the helical structure 221 may have a start end located within the support body 230 and a stop end located downstream of the start end in the power transmission direction F.

The end stop may be located outside or inside the first bearing. That is, all of the spiral structure 221 may be located inside the first bearing, or a part of the spiral structure 221 may be located inside the first bearing and a part of the spiral structure 221 may be located outside the first bearing. The helical structure 221 extends from within the first bearing inner helix to outside the first bearing. To improve the sealing effect and prevent the leakage of the return fluid, the spiral structure 221 may extend on the outer wall of the driving shaft (the connecting shaft 220) to the downstream of the output port 202 in the power transmission direction F.

The length of the spiral structure 221 in the axial direction (power transmission direction F) outside the first bearing is 1mm or more. More preferably, the axial length of the spiral structure 221 outside the first bearing is within 5mm, or extends to the connection point of the connection shaft 220 and the first shaft 350. The axial length of the first bearing ranges from 3 to 5mm, and the depth of the spiral groove 222 ranges from 0.05 to 0.2 mm.

As shown in fig. 9 and 10, the distal end of the drive shaft extends out of the catheter 300 and is fixedly sleeved by the impeller 410, so that the impeller 410 can rotate together with the drive shaft. A pump casing 400 is arranged at the far end of the guide pipe 300, the rear end of the pump casing 400 is sleeved on the outer wall 301 of the guide pipe 300 and is provided with a pump outlet 402.

The pump housing 400 may be formed by a cover 401, with a collapsible stand 404 disposed within the pump housing 400, the stand 404 supporting the cover 401 to form a pump chamber. The distal end of the cover 401 is sleeved on the stent 404, the proximal end is sleeved on the outer wall of the catheter 300, and the distal end of the stent 404 which is not covered by the cover 401 forms a pump inlet 403.

The pump inlet 403 and pump outlet 402 are located on the front and rear sides of the impeller 410, respectively, and the proximal end of the bracket 404 is connected to the distal end of the catheter 300, the distal end is provided on a rear bearing block 405 (distal bearing chamber) at the distal end of the drive shaft, and the distal end of the rear bearing block 405 is connected to the non-invasive support 500.

As shown in fig. 11 and 12, the stent 404 is made of a memory alloy, and may be an integrally molded structure made of a nickel-titanium alloy. After the sheath constraint is lost, the stent 404 returns to its shape to hold the graft 401 open. The frame 404 is a spindle structure having a lattice structure, and the multi-lattice structure is combined with the memory alloy material to facilitate the folding and unfolding of the frame. The impeller 410 is housed within the stent 404 and is positioned within the graft 401.

The impeller 410 is secured to an impeller shaft or second shaft 355 (which may be connected to or integral with the first shaft 350), the impeller shaft 355 being located within the support 404, the distal end being rotatably supported in the distal bearing chamber 405.

The pump assembly is a collapsible pump assembly having a radially compressed state and a radially expanded state. In the pump assembly corresponding intervention configuration, the support 404 and the impeller 410 are in a radially compressed state. At this point, the pump assembly can be delivered in the subject's vasculature in a first, smaller radial dimension. In the pump assembly corresponding operating configuration, the support 404 and impeller 410 are in a radially expanded state. At this point, the pump assembly may pump blood at a desired location, such as within the left ventricle, with a second radial dimension that is greater than the first radial dimension.

From the viewpoint of alleviating pain of the subject and ease of intervention, it is desirable that the pump assembly be small in size. Whereas a large flow rate is desirable for the pump assembly due to the need to provide a strong ancillary function to the subject, a large flow rate generally requires a large pump assembly size.

By providing a collapsible pump assembly, the pump assembly has a smaller collapsed size and a larger deployed size, which allows for ease of intervention and ease of pain relief for the subject during the intervention/delivery process, as well as providing a high flow rate.

As shown in fig. 11, the stent 404 comprises a generally cylindrical body section 40, a generally conical inlet section 41 and outlet section 42 at either end of the body section 40, the body section 40 having a smaller mesh area than the inlet section 41 and/or outlet section 42. In the pump assembly deployed state, the outer wall of the body section 40 contacts the inner wall of the membrane 401, supporting the membrane 401 for deployment.

As shown in FIG. 12, the (at least one) mesh of the main body segment 40 has two first apices 505 that are generally axially opposed, and two pairs of second apices 504 that are generally circumferentially opposed. The spacing between the two pairs of second vertices 504 is approximately equal, but less than the spacing between the two first vertices 505.

The long axis direction of the meshes of the main body section 40 is consistent with the axial direction of the stent 404, the meshes can be elongated according to the long axis direction, the radial contraction of the stent 404 is realized, the axial telescopic deformation can be better adapted, the controllable smooth contraction of the stent 404 and the covering film 401 is completed, the contraction is smoothly completed after the expected operation is completed in vivo, and the stent is convenient to move out of the body.

The maximum dimension of the mesh openings of the main body section 40 in the axial direction is larger than the maximum dimension thereof in the circumferential direction. In the case of other irregular polygonal apertures, or with a maximum dimension that is not the spacing between vertices, the cells of the body segment 40 have a circumferential maximum dimension that is 1.2 to 3 times their axial maximum dimension. The two points providing the circumferential dimension are substantially circumferentially opposed and the two points providing the axial dimension are substantially axially opposed.

The mesh of the main body section 40 is a plurality of support mesh 50, and the support mesh 50 is a closed polygonal hole to form a stable support structure to stabilize the pump gap. The supporting mesh 50 is at least two polygonal holes with unequal side lengths, and the polygonal holes may be irregular polygonal holes or polygonal holes with mirror symmetry structures, which is not limited in the present application.

For example, the support mesh 50 is a mirror symmetrical mesh, the length direction of the smallest edge of which is parallel to the axial direction, and comprises two parallel first edges 501 and two parallel second edges 502. The second vertex 504 is located at least one end of the second edge 502, and the first vertex 505 is located at least one end of the first edge 501.

The support meshes 50 may be quadrangular holes such as rhombic holes or hexagonal holes. In the diamond mesh embodiment, the support mesh 50 has two axial first vertices 505, which form the leading and trailing crests 510a, 510b of the sawtooth structure for the first and second arrises 501, 502, respectively. Two second apexes 504 are opposite to each other in the circumferential direction, and the first edge 501 and the second edge 502 form a left crest and a right crest of the saw-tooth structure, respectively.

In the embodiment of hexagonal holes, the support mesh 50 further comprises two third edges 503 parallel to the axial direction. A third edge 503 is connected between a first edge 501 and a second edge 502, and the first edge 501, the second edge 502, and the third edge 503 enclose the closed hexagonal support mesh 50.

The axial size of the supporting mesh 50 is increased through the third edge 503, so that the axial size of the supporting mesh 50 is the main size, and further, when the supporting mesh is put into the sheath, the supporting mesh can be folded smoothly along the axial direction, and the resistance force during folding is reduced. Further, the length of the second edge 502 is equal to the length of the first edge 501, and the length of the third edge 503 is smaller than the length of the second edge 502. The third edge 503 is the smallest edge that supports the mesh 50, providing the smallest edge length of the mesh.

The two axial end points of the third edge 503 respectively form second vertexes 504, the rear end point of the third edge 503 in the axial direction is shared with a first edge 501, the shared end point forms a second vertex 504, the distal end point of the third edge 503 in the axial direction is shared with a second edge 502, and the shared end point forms another second vertex 504. The circumferential spacing of the two third edges 503 is the spacing of the two circumferentially opposite second apexes 504. The common end point of the first edge 501 and the second edge 502 forms a first vertex 505.

At least one of the first edge 501, the second edge 502 and the third edge 503 is a linear edge as a whole, a plurality of edges of the mesh form a polygonal mesh, and the linear edge as a whole can be a linear edge without bending as shown in fig. 11 and 12. Alternatively, the edge may be a straight edge that allows some slight curvature and still be visually perceived as a polygon, such as the edge shown in fig. 13.

In this case, the edges of the polygonal meshes are of a generally rectilinear configuration.

The length of the first edge 501 ranges from 1mm to 2mm, the length of the third edge 503 ranges from 0.15mm to 0.35mm, and the ratio of the lengths of the first edge 501 and the third edge 503 ranges from 3: 1 to 5: 1. First apex 505 and second apex 504 are provided with first and second rounded structures, respectively, to provide a smooth transition between the edges of support mesh 50, creating a stable support structure. The arc length of the first rounding structure is greater than the arc length of the second rounding structure.

It is noted that the above numerical values include all values of lower and upper values that are incremented by one unit from the lower limit value to the upper limit value, and that there may be an interval of at least two units between any lower value and any higher value.

For example, the first edge 501 is illustrated as having a length in the range of 1mm to 2mm, preferably 1.1 to 1.9mm, more preferably 1.2 to 1.8mm, and even more preferably 1.3 to 1.7mm, for the purpose of illustrating equivalents such as 1.4mm, 1.5mm, and 1.6mm not expressly enumerated above.

For other definitions of numerical ranges appearing herein, reference is made to the above description and further description is omitted.

The plurality of support meshes 50 are sequentially arranged along the circumferential direction to form support hole rings (50a, 50b, 50c), and the plurality of support hole rings are arranged along the axial direction to form the main body section 40. As shown in fig. 12, along the circumferential direction, the first edge 501 and the second edge 502 are alternately arranged to form a sawtooth ring 520 in a sawtooth structure, and two axially adjacent sawtooth rings 520 are opposite to each other to form a support ring.

As shown in fig. 11 and 13, the inlet section 41 is located at the front side of the body section 40 at the distal end of the stent 404, and the axial length of the mesh of the inlet section 41 is greater than the axial length of the support mesh 50.

The meshes of the inlet section 41 are overflowing meshes for blood to flow into. The mesh openings of the inlet section 41 extend in length from the distal end to the proximal end of the mesh openings, not in a radial projection on the axis.

The axial length of the support mesh 50 in this embodiment is equal to its radial projection length on the axis.

The meshes of the inlet section 41 comprise first overflowing meshes 52a and second overflowing meshes 52b which are alternately distributed along the circumferential direction, and the length of the first overflowing meshes 52a is smaller than that of the second overflowing meshes 52 b. The first overflowing mesh 52a is a closed hole, and the second overflowing mesh 52 is a non-closed hole.

The distal end of the inlet section 41 is provided with a front connecting portion 44, the front connecting portion 44 comprising a plurality of circumferentially dispersed connecting legs 440. The connecting leg 440 is a T-shaped structure with a distal end having a leg end 45 with a circumferential dimension greater than the leg shaft. The connecting legs 440 may snap into a snap groove in the outer wall of the distal bearing housing 405, the distal end of the snap groove communicating with an annular groove, the leg ends 45 snap into the annular groove and the discrete plurality of connecting legs 440 are secured to the distal bearing housing 405 by an outer ferrule.

In one embodiment, the collar is a heat shrink tubing secured over the distal bearing chamber 405 by heat shrinking to fit the plurality of connecting legs of the bracket 404 into receiving slots on the outer wall of the distal bearing chamber 405.

The second transfer mesh 52b extends from the inlet section 41 to the front connection portion 44 until an opening 523 is formed at an end of the front connection portion 44. Part of the second through-flow mesh 52b is located at the inlet section 41 and part of the second through-flow mesh 52b is located at the front connection portion 44. The gap between the two connecting legs 440 forms part of the second flow-through mesh 52b at the front connecting portion 44, which is filled by the outer wall bulge of the distal bearing housing 405 when mounted.

The circumferential width of the first transfer mesh openings 52a gradually decreases as they extend from the front tooth tops 510a toward the junction, and the front junction 525 or the first transfer mesh openings 52a do not exceed the transition point between the inlet section 41 and the connecting sub-pipe 43. The second flow-passing mesh 52b includes a front section 521 whose circumferential width is kept constant in the axial direction and a rear section 522 whose circumferential width is gradually reduced in the axial direction toward a direction away from the main body section 40. Wherein the front section 521 is located at the front connection 44.

In the embodiment shown in fig. 11 and 13, the rear section 522 has a substantially constant circumferential width as it extends in the axial direction. The rate of change in the circumferential width of the section of the second flow-passing mesh 52b between the leading tooth crest 510a and the intersection (the trailing section 522) at different positions in the axial direction is less than 10%. The circumferential width of the rear section 522 is greater than or equal to the circumferential width of the front section 521, with a transition point between the rear section 522 and the front region, which is located approximately at the transition point between the inlet section 41 and the front connection 44.

The inlet section 41 includes a plurality of front stretching ribs 528 extending from the front tooth top 510a to the front connecting portion 44, ends of two adjacent front stretching ribs 528 away from the main body section 40 meet to form a front junction 525, and the front junctions 525 are connected to or extend to the connecting legs 440 in a one-to-one correspondence. The number of front tension ribs 528 is equal to the number of front crests 510a of a serrated ring 520 and is 2 times the number of connecting legs 440.

The outlet section 42 is substantially similar to the inlet section 41, except that the third and fourth flow-passing mesh openings 51a, 51b are closed openings. Wherein the outlet section 42 is located at the proximal end of the stent 404. The mesh of the outlet section 42 extends for a length between the axial ends that is greater than the axial length of the support mesh 50.

The meshes of the outlet section 42 comprise third and fourth flow-passing meshes 51a and 51b alternately distributed in the circumferential direction. Wherein the third and fourth overflowing mesh holes 51a and 51b have different shapes or areas, and the length of the third overflowing mesh hole 51a is smaller than that of the fourth overflowing mesh hole 51 b.

The proximal end of the outlet section 42 is provided with a connecting secondary tube 43, and the connecting secondary tube 43 is fixed on the catheter 300 or the bearing mounting part in a hot melt or adhesive manner, so that the proximal end of the bracket 404 is fixed. The secondary connection pipe 43 may further have a locking hole 431 for locking the outer wall of the guide pipe 300 or the bearing mounting portion.

Fourth flow-through mesh 51b extends from outlet section 42 to secondary connecting tube 43 and forms a closed-cell end at secondary connecting tube 43. Part of the fourth overflowing mesh 512 is located at the outlet section 42, and part of the fourth overflowing mesh 511 is located at the connecting sub-pipe 43. The fourth overflowing net hole 51b does not extend to the rear end beyond the catching hole 431 of the connection sub-pipe 43.

The outlet section 42 includes a plurality of rear extension ribs 518 extending from the rear tooth top 510b to the connecting secondary pipe 43, and ends of two adjacent rear extension ribs 518 away from the main body section 40 meet to form a rear junction, and the rear junctions are connected to or extend to the connecting legs 440 in a one-to-one correspondence. The number of rear tension ribs 518 is equal to the number of rear crests 510b of a serration ring 520, and is 2 times the number of connecting legs 440.

The third flow-passing meshes 51a gradually decrease in circumferential width as they extend from the rear tooth crests 510b toward the rear intersection, and the rear intersection or second flow-passing meshes 52b do not exceed the transition points between the outlet section 42 and the connecting secondary pipe 43. The circumferential width of the portion of the fourth transfer mesh holes 51b located between the connection sub-pipe 43 is kept constant in the axial direction, and the rate of change in the circumferential width of the section of the fourth transfer mesh holes 51b located between the rear tooth crests 510b and the rear intersection point at different positions in the axial direction is less than 10%.

Referring to fig. 9 and 10, the driving shaft (specifically, the second shaft 355) is further sleeved with a second bearing 331 (a first proximal bearing) and a third bearing 332 (a second proximal bearing) at intervals, and the third bearing 332 is located downstream of the second bearing 331 along the power transmission direction F of the driving shaft. A spaced annulus 333 is formed between the second and third bearings 331, 332 that communicates with the output of the second flow passage 600.

An output gap 335 is formed between the third bearing 332 and the drive shaft communicating the spaced annulus 333 with the exterior of the conduit 300, and a communication gap 334 is formed between the second bearing 331 and the drive shaft communicating the input end of the first flow passage 700 with the spaced annulus 333. The flow direction of the communication gap 334 and the output gap 335 are reversed.

Conduit 300 has a rear projecting tube 313 provided at the rear end of main tube 311, a rear step 316 is provided between main tube 311 and rear projecting tube 313, and rear step 316 may be an annular step similar to front step 315.

The rear protrusion tube 313 is sleeved with a bearing sleeve 330 (proximal bearing chamber), the bearing sleeve 330 is sleeved with a fixing sleeve 340, and the rear step 316 provides positioning for the bearing sleeve 330 and the fixing sleeve 340 when sleeved outside the rear protrusion tube 313. The third bearing 332 and the second bearing 331 are fixed in the bearing sleeve 330 at intervals, the driving shaft is sleeved with a limiting sleeve in the bearing sleeve 330, and the limiting sleeve is positioned at the upstream of the second bearing 331 along the power transmission direction F to position the second bearing 331.

The outer wall of the bearing sleeve 330 is provided with a plurality of (for example, two) liquid tanks spaced along the circumferential direction corresponding to the cavity forming the second flow channel 600, and the fixing sleeve 340 is sleeved on the outer wall of the bearing sleeve 330 to cover the liquid tanks to form a communication flow channel 341. Communication holes 342 (one in each of the two liquid tanks) are formed at the rear end of the communication flow path 341 (the rear end bottom wall of the liquid tank), and the communication holes 342 are located between the third bearing 332 and the second bearing 331 and communicate with the space annulus 333.

As shown by the liquid flow arrows in fig. 10, liquid (priming fluid) enters the separation annulus 333, part of the liquid enters the communication gap 334 in the opposite direction of the power transmission direction F until the first flow passage 700 forms a backflow, and the other part of the liquid directly enters the output gap 335 in the power transmission direction F, is output outwards, enters the pump cavity, and is discharged into the body by the pump outlet 402.

As shown in fig. 14 to 17, in the power transmission assembly according to another embodiment of the present invention, an outer flow passage 600 is formed between an outer wall of the drive shaft and an inner wall of the guide duct 300, and an inner flow passage 800 is provided in the drive shaft to be coextensive with or extend side by side with the outer flow passage 600. The outer flow channel 600 has a first discharge port 605 at the distal end of the catheter 300 and the inner flow channel 800 has a second discharge port 810 at the distal end of the drive shaft.

As shown in fig. 14, the power transmission assembly is further provided with a perfusate input part 201, and the perfusate input part 201 communicates with one of the outer flow channel 600 and the inner flow channel 800. The perfusate is inputted to the outer flow path 600 and the inner flow path 800 through the perfusate input part 201. The wall of the driving shaft is provided with a communicating portion communicating the inner flow passage 800 with the outer flow passage 600, and the outer flow passage 600 and the inner flow passage 800 are separated by the wall of the driving shaft and communicate with each other through the communicating portion. The perfusate input part 201 inputs the perfusate into one of the outer flow channel 600 and the inner flow channel 800, and the other of the outer flow channel 600 and the inner flow channel 800 inputs the perfusate through the communicating part.

For example, the outer channel 600 directly communicates with the perfusate input part 201, and the inner channel 800 indirectly communicates with the perfusate input part 201 via the communication part. Alternatively, the inner channel 800 is directly communicated with the perfusate input part 201, and the outer channel 600 is indirectly communicated with the perfusate input part 201 through the communicating part.

As shown in fig. 16 and 19, the first discharge port 605 is located on the proximal end side of the impeller 410, and the perfusate in the outer flow channel 600 is discharged from the proximal end of the support 404 through the first discharge port 605. As shown in fig. 17 and 20, the second discharge port 810 is located at the distal end side of the impeller 410, and the perfusion fluid in the inner channel 800 is discharged from the distal end of the stent 404 through the second discharge port 810.

By allowing the perfusate in the outer channel 600 and the inner channel 800 to flow out at the proximal and distal sides of the impeller 410, respectively, blood can be prevented from entering the catheter 300, the drive shaft or the distal bearing chamber 405 at the proximal/distal ends of the impeller 410 and causing thrombus.

In another embodiment, the perfusate input part 201 communicates with at least one of the outer flow channel 600 and the inner flow channel 800. Further, the perfusate inlet part 201 communicates with one of the outer flow channel 600 and the inner flow channel 800, and particularly, the perfusate inlet part 201 directly communicates with the outer flow channel 600 and indirectly communicates with the inner flow channel 800 via a communication part.

When the blood pump is in an operating state in which the impeller 410 is rotating, the impeller 410 is confined between the first exhaust 605 and the second exhaust 810.

As shown in fig. 16 and 17, the impeller 410 has a proximal bearing chamber 330 provided on the proximal side and a distal bearing chamber 405 provided on the distal side. The proximal bearing chamber 330 is provided with proximal bearings for supporting rotation of the drive shaft, such as a first proximal bearing 331, a second proximal bearing 332 (refer to the second and third bearings 331, 332 in the previous embodiment) that are axially spaced apart.

Distal bearing housing 405 is provided with a distal bearing 4051 for supporting rotation of the drive shaft. The perfusate in the outer flow channel 600 is drained through the proximal bearings 331, 332 and the perfusate in the inner flow channel 800 is drained through the distal bearing 4051.

To allow the perfusate to drain and avoid blood back flow, the pressure of the perfusate in the first drain 605 is greater than the pressure of the blood near the first drain 605 and the pressure of the perfusate in the second drain 810 is greater than the pressure of the blood near the second drain 810. Thus, the perfusate can lubricate the bearing, and can prevent blood from entering the bearing to damage the bearing, so as to prevent thrombus from forming in and near the bearing.

As shown in fig. 17, in order to slow down the flow rate of the perfusion fluid entering the body and be suitable for being received by the human body, the distal end of the inner flow channel 800 is provided with a diffuser, and the port of the diffuser is a second discharge port 810. The diffuser section is flared and increases in cross-sectional area as it extends from its proximal end to its distal end.

As shown in fig. 14-17, the communication portion comprises a wall of at least a partial length of the drive shaft within the conduit 300 that is permeable to liquid. At least a portion of the wall of the drive shaft within the conduit 300 is of a liquid permeable construction. The outer flow channel 600 and the inner flow channel 800 are both continuous flow channels, both extending from the proximal end to the distal end of the catheter 300.

The proximal end of the catheter 300 communicates with the perfusate input 201 to communicate the proximal end of the outer channel 600 with the perfusate input 201. The outer flow channel 600 is a high pressure flow channel and the inner flow channel 800 is a low pressure flow channel, and the perfusion fluid penetrates through the wall of the drive shaft under the action of the pressure difference and enters the inner flow channel 800.

The proximal end of the drive shaft is blocked or provided with a flow blocking structure proximal to the perfusate input 201. In this way, leakage of the perfusion fluid near the drive shaft into the motor 101 is avoided.

The perfusate input part 201 is a perfusate input port on the coupling body 200, and the perfusate input port is communicated with an input flow channel. The perfusate inlet port communicates with the lumen of the catheter 300 via an inlet flow channel through which the drive shaft passes and a sealing means is provided on the proximal side of the inlet flow channel to prevent proximal leakage of perfusate.

The present application is not limited to embodiments in which the outer flow channel 600 communicates with the perfusate input 201. In one possible embodiment, the inner channel 800 may also communicate with the perfusate input 201, and the perfusate in the inner channel 800 flows radially outward into the outer channel 600. Specifically, the inner channel 800 of the driving shaft is communicated with the extracorporeal perfusate input part 201, the proximal end of the driving shaft is connected with the output shaft of the motor 101 through the connecting shaft 220, the output shaft and the connecting shaft 220 form a hollow structure, and the output shaft of the motor 101 penetrates out from the tail end thereof to provide a perfusate input interface.

The first shaft 350 is a flexible shaft that facilitates insertion into a vessel to accommodate bending of the vascular structure and to deliver the distal pump assembly to a desired location. The second shaft 355 is connected to the impeller 410, and specifically, the second shaft 355 is inserted into a hub of the impeller 410. The second shaft 355 is stiffer than the first shaft 350, and is a rigid or stiff shaft that, in cooperation with the proximal and distal bearings 331, 332, 4501 on either side, provides support for the impeller 410 to achieve the desired stabilization of the position of the impeller 410 within the pump casing.

The distal end of the first shaft 350 and the proximal end of the second shaft 355 are connected at a location within the distal end of the catheter 300, which may be by any suitable means, such as welding.

The location of attachment of the stent 404 to the catheter 300 is proximal of the second shaft 355. The proximal end of the bracket 404 is provided with a secondary connection tube 43, and the catheter 300 is connected with the secondary connection tube 43 by hot melting or snap connection. Alternatively, the catheter 300 is connected to the connection sub-tube 43 via the proximal bearing chamber 330, possibly by gluing the distal end of the catheter 300 to the proximal bearing chamber 330 and by snap-fitting the connection sub-tube 43 to the proximal bearing chamber 330.

As described above, in order to provide sufficient strength support to the impeller 410 so that it is stably held in position within the pump casing, the second shaft 355 passing through the hub is a hard shaft and is not easily bent. Therefore, in order not to make the second shaft 355, which is relatively rigid, affect the bending performance of the working portion of the front end of the blood pump (including the pump assembly and the front catheter portion introduced into the human body), the proximal end of the second shaft 355 is located inside the proximal end of the stent 404 or inside the connection sub-tube 43, but does not protrude out of the connection sub-tube 43. That is, the proximal end of the second shaft 355 is located within the connection sub-tube 43 and does not protrude out of the connection sub-tube 43.

In a scenario where the pump assembly is to be collapsed, the collapsed pump assembly is relatively rigid and generally cannot be bent. Over-bending of the pump assembly during the intervention then needs to be achieved by virtue of the bending of the catheter 300 to which it is connected. With the above design, the proximal end of the second shaft 355 is located inside the proximal end of the stent 404 or inside the connecting secondary tube 43, so that the proximal end of the second shaft 355 does not protrude out of the connecting secondary tube 43 and enter the catheter 300 too much, and therefore the stiffness of the catheter 300 is not increased due to the gain of the second shaft 355, which allows the distal end portion of the catheter 300 connected with the connecting secondary tube 43 to maintain a better flexibility, thereby ensuring the overbending performance of the pump assembly during the interventional procedure.

The communication portion extends from a proximal end of the first shaft 350 to a distal end of the first shaft 350. The first shaft 350 is made of a braid, the walls of which are of a liquid permeable structure, and the communication portions are braid slits extending through the walls of the first shaft 350. The first shaft 350 is a multi-layer braided structure, e.g., a layer-by-layer wrap of 2, 3, 4, or more layers.

The plurality of braided layers of the first shaft 350 are in a layer-by-layer sheathing relationship, and the braided layers are spirally braided. Wherein, the spiral direction of two adjacent weaving layers is opposite. The multilayer braided structure is a spiral twisted structure, and the rotating directions of the inner braided layer and the outer braided layer are opposite.

By providing the first shaft 350 with the braiding twisting structure having the braiding twisting directions opposite to the twisting directions of the inner and outer adjacent braiding layers, a spiral groove or protrusion is formed on the outer surface of the first shaft 350, the twisting direction of the spiral groove or the spiral protrusion is opposite to the rotating direction of the driving shaft 300, so that a pump effect is formed, the perfusion fluid is pumped to the far end, the blood can be prevented from entering the far end of the catheter 300, and the thrombus can be prevented from being formed at the far end of the catheter 300.

The communicating portion extends in the circumferential and axial directions of the first shaft 350 to communicate the outer flow passage 600 with the inner flow passage 800 in a fluid-permeable manner, and at least a portion of the wall of the driving shaft located in the guide tube 300 is of a fluid-permeable structure. The first shaft 350 has a liquid-permeable structure as a whole, and a wall of a portion of the first shaft 350 covered by the guide tube 300 forms a communicating portion communicating the inner flow path 800 and the outer flow path 600. There is always fluid communication or fluid penetration between the inner flow channel 800 and the outer flow channel 600 to the connection of the first shaft 350 and the second shaft 355.

In the embodiment of perfusate return described above, the drive shaft comprises a connection shaft 220 having a helical structure 221 on its outer wall. It is noted that in the embodiment described herein where the perfusate is not recirculated but separately expelled from the distal end of the catheter 300 and the distal bearing chamber 405, the outer wall of the first shaft 350 comprised by the drive shaft may also form the helical structure 221.

In this embodiment, the perfusion fluid first flows forward within the outer flow channel 600, i.e. within the catheter 300 or outside the first shaft 350. During flow, a portion of the perfusion fluid seeps into the first shaft 350, i.e., the inner channel 800. The pump effect formed by the spiral structure 221 on the outer wall of the first shaft 350 during rotation can generate forward force on the perfusate in the external flow channel 600, so that smooth flowing of the perfusate is ensured, and the perfusate is prevented from being blocked.

For the same purpose, the inner wall of the first shaft 350 may also be formed with such a spiral structure 221 in order to provide a continuous forward flow power to the perfusion fluid in the inner channel 800.

The helical structure 221 formed by the outer and/or inner walls of the first shaft 350 may be formed by the helical braid described above. The braid is typically helically woven from a single strand of material that is generally circular in cross-section so that the braid surface naturally forms helical ridges or grooves. Wherein the protrusions are the outer contours of the single strand of material and the recesses are formed between the woven material.

Therefore, in order to form the spiral structure 221 corresponding to the above description on the outer wall of the first shaft 350, in the case where the first shaft 350 has a spiral braiding structure, it is only necessary to make the spiral direction of the outermost braided layer opposite to the rotation direction of the first shaft 350.

Also, the spiral direction of the innermost braid is opposite to the rotation direction of the first shaft 350, and it is possible to realize the spiral structure formed on the inner wall of the first shaft 350 in accordance with the above description.

Thus, the spiral direction of the innermost and outermost woven layers is the same. In the case where it is stated above that the direction of the spirals of adjacent braids is opposite, the first shaft 350 should comprise an odd number of braids greater than 1, for example 3 or 5 braids.

Further, since the first shaft 350 needs to transmit torque, the outermost spiral braid tends to be screwed due to torque action during rotation by the structural design that the spiral direction of the outermost braid is opposite to the rotation direction of the first shaft 350, and the outermost braid is prevented from being loosened.

Thus, during rotation, the braid, which is spiraled in the opposite direction to the rotation of the first shaft 350, tends to have a smaller diameter. If all of the helical braid of the first shaft 350 is rotated in the opposite direction to the first shaft 350, the diameter of the first shaft 350 may not be stably maintained as the operation time increases.

As described above, there are two adjacent braids in the first shaft 350 that have opposite helical directions. That is, the first shaft 350 includes a braid having a helical direction identical to a rotation direction thereof, which tends to increase in diameter or to be loosened due to a torque action during rotation.

Then, the braid spiraling in the opposite direction of the rotation of first shaft 350 applies an inward compressive force to the inner braid, while the braid spiraling in the same direction of the rotation of first shaft 350 applies an outward expansive force to the outer braid. Thereby, diameter variations or force effects of adjacent braids are at least partially compensated for, thereby stably maintaining the diameter of the first shaft 350.

The stable maintenance of the diameter of the first shaft 350 is advantageous in stabilizing the shape of the external flow path 600, thereby stabilizing the flow rate and the flow area of the perfusion fluid.

The above-described scheme of forming the helical structure 221 via the helical braid configuration of the first shaft 350 is illustrative and not intended to be limiting. That is, in other alternative embodiments, it is also possible, for example, for the outer and/or inner walls of the first shaft 350 to be flat or smooth walls on which the helical structure 221 is formed by machining helical grooves or protrusions.

The connection point of the first shaft 350 and the second shaft 355 is located proximal to the bearing mount 340. The bearing mounting portion 340 is sleeved outside the second shaft 355, and the near-end bearing is sleeved outside the second shaft 355 to rotatably support the second shaft 355. A communication gap for communicating the outer flow path 600 with the first discharge port 605 is formed between the bearing mounting portion 340 and the second shaft 355.

The bearing mount 340 is located at the distal end of the catheter 300, and houses proximal bearings 331, 332 (1 or more proximal bearings are not excluded in other embodiments). The proximal bearings 331 and 332 are fitted around the drive shaft (the second shaft 355), and the first discharge port 605 is located on the distal side of the proximal bearing 332.

As shown in fig. 16 and 19, the proximal bearing includes first and second spaced proximal bearings 331 and 332. The outer wall of the drive shaft is provided with a stop 356, the stop 356 being axially movably located between the first and second proximal bearings 331, 332.

The stopper 356 is a stopper ring provided on the outer wall of the drive shaft, or a stopper projection such as a projection provided on the outer wall of the drive shaft. A stopper flow gap is formed between the outer wall of the stopper 356 and the inner wall of the bearing mounting portion 340.

The communication gap includes the internal flow gap of the first proximal bearing 331, the stopper flow gap, and the internal flow gap of the second proximal bearing 332. The first and second proximal bearings 331 and 332 have flow gaps through which fluid can pass, and do not block the fluid from passing.

Of course, the first proximal bearing 331 and the outer wall of the second shaft 355 may form a first flow gap therebetween, and the second proximal bearing 332 and the outer wall of the second shaft 355 may form a second flow gap therebetween, so as to further facilitate the fluid to flow therethrough.

The stopper 356 and the first proximal bearing 331 have a first spacing space therebetween that communicates the stopper flow gap with the first proximal bearing 331. The stopper 356 and the second proximal bearing 332 have a second clearance space therebetween that communicates the stopper flow gap with the second proximal bearing 332.

A tortuous perfusate output path is constructed through the first proximal bearing 331, the stop flow gap and the second proximal bearing 332, so that the flow velocity and the impact pressure of the perfusate are reduced, and the damage or other adverse effects caused by the fast entering of the perfusate into a human body are avoided.

A first discharge port 605 is located distal to the proximal bearing and opens into the proximal end of the support 404. Thus, when the perfusion fluid in the outer channel 600 flows forward, the perfusion fluid passes through the proximal bearings 331 and 332, and the proximal bearings 331 and 332 are lubricated.

Meanwhile, when the perfusate is discharged from the first discharge port 605, a high pressure area within a certain range is formed at the distal end of the catheter 300, thereby preventing blood from entering the catheter 300 and preventing thrombus from being formed.

In some embodiments, bearing mount 340 includes a proximal bearing chamber 330 attached to the distal end of catheter 300. In other embodiments, the bearing mount 340 may also be formed by the distal portion of the catheter 300 or the connecting sub-tube 43 of the stent 404, and the present application is not limited solely by the additional separately provided proximal bearing chamber 330.

The distal end of second shaft 355 is rotatably supported within distal bearing chamber 405, and the distal end of bracket 404 is coupled to distal bearing chamber 405. A second discharge port 810 is located in the distal bearing housing 405, with the proximal end of the distal bearing housing 405 and the drive shaft defining a perfusate discharge port therebetween.

The noninvasive support piece 500 connected with the far end of the far end bearing chamber 405 is of a flexible pipe body structure, and is represented as a flexible bulge with an arc-shaped or winding end, so that the flexible support piece 500 is supported on the inner wall of the heart chamber in a noninvasive or nondestructive mode, a blood inlet 403 of the pump assembly is separated from the inner wall of the heart chamber, the suction inlet of the pump assembly is prevented from being attached to the inner wall of the heart chamber due to the reaction force of fluid (blood) in the working process of the pump assembly, and the effective area of pumping is ensured.

The proximal end of the non-invasive support 500 is inserted into the distal bearing chamber 405 and the distal end of the second shaft 355 slidably extends into the distal bearing 4051. The proximal end face of the atraumatic support 500 is spaced from the distal end face of the second shaft 355 and is adapted to provide a clearance for axial relative movement of the second shaft 355 relative to an external sheathing component, such as the stent 404, during intervention in the pump assembly.

As shown in fig. 17, a blocking member 550 is disposed within distal bearing chamber 405 between the distal end of second shaft 355 and the proximal end of atraumatic support 500. A step 551 is provided in distal bearing chamber 405 and a closure member 550 is clamped between step 551 and the proximal end of atraumatic support member 500.

Thus, the perfusate in the inner channel 800 is discharged from the second discharge port 810 into the distal bearing chamber 405, flows only in the reverse direction due to the presence of the blocking member 550, then flows through the distal bearing 4501 to lubricate the distal bearing, and then is discharged from the perfusate discharge port out of the distal bearing chamber 405, into the frame 404, and finally into the human body. Thus, the perfusate discharged from the perfusate discharge port may form a range of high pressure zones proximal to the distal bearing chamber 405, thereby preventing blood from entering the distal bearing chamber 405 and preventing thrombus formation.

The closure 550 is a flexible check valve, such as a check valve, having a resealable passage through which the guidewire may pass, the resealable passage closing upon removal of the guidewire to maintain the closure in place. The flexible hemostatic valve can be made of plugging rubber or silica gel, when the guide wire passes through the resealable channel, the flexible hemostatic valve is attached to the guide wire to maintain a plugging state, and after the guide wire is withdrawn, the flexible hemostatic valve resets to close the wire feeding hole and still maintain the plugging state of the position.

The occluding member 550 occludes the proximal end of the non-invasive support member 500 to prevent blood from entering the non-invasive support member 500 during operation of the pump assembly.

The non-invasive support 500 has a hollow lumen 555, the hollow lumen 555 and the hollow lumen of the drive shaft forming a guidewire transit path having an inner diameter equal to or slightly larger than the outer diameter of the guidewire. For example, the inner diameter of the hollow lumen 555 is 1-1.2 times the diameter of the guidewire.

As shown in fig. 17, a closure member 550 is positioned distal to the distal end of the second shaft 355. The flexible closure 550 is spaced from the distal end of the second shaft 355 to provide axial play of the second shaft 355 for axial movement of the second shaft 355.

The closure 550 may constitute an axial stop for the second shaft 355, defining a far dead center position of axial movement of the closure 550. Of course, in the case of the stop 356, when the stop 356 contacts the second proximal bearing 332, the distal end of the second shaft 355 does not contact the blocking member 550, but is spaced apart from the blocking member 550, so as to prevent damage to the blocking member 550 caused by axial movement of the second shaft 355.

As shown in fig. 18-21, in some embodiments, no closure 500 may be provided between second discharge port 810 and noninvasive support 500, with the interior of distal bearing chamber 405 communicating second discharge port 810 with hollow lumen 555. The distal port of the non-invasive support 500 constitutes a perfusate discharge port. At this time, due to the higher pressure of the perfusion fluid, the distal bearing 4051 may also constitute a perfusion fluid discharge path, and a perfusion fluid discharge port is formed at the proximal side of the distal bearing 4051, at which time the perfusion fluid may be discharged outwardly at the distal end port of the non-invasive support 500 and the proximal side of the distal bearing 4051 at the same time.

The perfusion fluid flows out through the second outlet 810 and enters the non-invasive support 500, and is discharged from the distal port of the non-invasive support 500 and the proximal side of the distal bearing 4051, while blood is prevented from entering the non-invasive support 500 and the distal bearing chamber 405 in the operating state of the pump assembly.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of subject matter that is disclosed herein is not intended to forego such subject matter, nor should the inventors be construed as having contemplated such subject matter as being part of the disclosed subject matter.