A delivery sheath and interventional blood pump delivery system

Abstract

The disclosed delivery sheath and interventional blood pump delivery system are used for delivering an interventional blood pump. The delivery sheath comprises a variable diameter delivery sheath and a sliding blocking member. The variable diameter delivery sheath comprises a connected variable diameter delivery sheath proximal tube segment and a variable diameter delivery sheath distal tube segment in a proximal-to-distal direction, the tube diameter of the variable diameter delivery sheath distal tube segment is larger than that of the variable diameter delivery sheath proximal tube segment, the variable diameter delivery sheath proximal tube segment is used for accommodating an interventional catheter, and the variable diameter delivery sheath distal tube segment is used for accommodating a pump head. After the pump head of the interventional blood pump is folded into the variable diameter delivery sheath distal tube segment, the interventional blood pump and the delivery sheath are inserted into a tearable interventional sheath which has been inserted into a blood vessel of a patient. After the delivery sheath enters the blood vessel, the tearable interventional sheath is pulled out from a puncture port, and the tearable interventional sheath is torn off from the delivery sheath outside the body, at this time, the variable diameter delivery sheath proximal tube segment with a smaller outer diameter is located at the puncture port, so that the puncture port maintains a smaller pore diameter, and the pain of the patient can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, more particularly, to a delivery sheath and an interventional blood pump delivery system. BACKGROUND

[0002] The interventional catheter pump, also known as an interventional blood pump (hereinafter referred to as a blood pump), is mainly used for high-risk percutaneous coronary intervention (PCI). The blood pump can reduce the work of the ventricle, provide necessary circulation support for the recovery of the heart and early evaluation of residual myocardial function. Such a blood pump needs to be introduced into the patient's heart through a percutaneous puncture through the blood vessel. In order to reduce the probability of complications of the puncture port and alleviate the pain of the patient, the blood pump has a small size at the puncture port.

[0003] For blood pumps that do not use a guide wire for intervention, a delivery sheath is required for intervention. The intervention process of the blood pump generally uses an intervention sheath to build a channel connecting the blood vessel and the external environment. The distal end of the intervention sheath is placed in the blood vessel through the puncture port, and the proximal end is left outside the human body. The blood pump catheter is retracted into the delivery sheath and can slide forward and backward. The delivery sheath is inserted into the intervention sheath together with the blood pump catheter and enters the blood vessel. Pushing the blood pump catheter further can place the blood pump in the working position in the ventricle along the blood vessel.

[0004] In combination Figure 1 , the blood pump catheter of the pump head radially expandable interventional blood pump 100 in the prior art includes a handle 110, an intervention catheter 120, a motor 130, a blood pumping catheter 140, an inlet protection bracket 150, and a pigtail catheter 160. The distal end of the blood pump catheter has a large diameter, and the proximal end has a small diameter. The blood pumping catheter 140 needs to use a delivery sheath to fold up the pump head of the expanded part, and then be inserted into the intervention sheath and into the blood vessel.

[0005] For the pump head radially expandable blood pump described above, if a common delivery sheath is used, the puncture port needs to be kept at a relatively large diameter when the blood pump provides long-term cardiac assistance, which can easily cause complications of the puncture port and increase the pain of the patient. There is a large gap between the inner wall of the delivery sheath and the outer wall of the intervention catheter of the blood pump. Blood flowing into and stagnating in the gap can cause blood clotting, and the generated thrombus can flow into the blood vessel of the patient, causing embolism and even stroke.

[0006] Therefore, how to smoothly place the blood pump catheter with inconsistent outer diameters in the working position in the ventricle, while keeping the puncture port at a relatively small size when the blood pump provides long-term cardiac assistance, has become a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0007] In view of the above, the present application aims to provide a delivery sheath for smoothly placing a blood pump catheter with inconsistent outer diameter into a working position in a heart chamber while keeping the puncture port at a smaller size when the blood pump provides long-term cardiac assistance.

[0008] Another object of the present application is to provide an interventional blood pump delivery system comprising the delivery sheath described above.

[0009] To achieve the above objects, the present application provides the following technical solutions.

[0010] A delivery sheath for delivering an interventional blood pump, the interventional blood pump comprising a connected interventional catheter and a pump head in a proximal-to-distal direction, the pump head being foldable and having a maximum outer diameter after folding greater than that of the interventional catheter, characterized in that it comprises a variable-diameter delivery sheath.

[0011] The variable-diameter delivery sheath comprises a connected variable-diameter delivery sheath proximal tube segment and a variable-diameter delivery sheath distal tube segment in a proximal-to-distal direction, the tube diameter of the variable-diameter delivery sheath distal tube segment being greater than that of the variable-diameter delivery sheath proximal tube segment, the variable-diameter delivery sheath proximal tube segment being used to accommodate the interventional catheter, and the variable-diameter delivery sheath distal tube segment being used to accommodate the pump head.

[0012] Optionally, in the delivery sheath described above, a sliding blocking member is further included, which is slidably arranged in the variable-diameter delivery sheath distal tube segment and used to seal the connection between the interventional catheter and the variable-diameter delivery sheath distal tube segment, and at a first limit position of the sliding of the sliding blocking member, an end face at the distal end of the sliding blocking member is flush with an end face at the distal end of the variable-diameter delivery sheath distal tube segment.

[0013] Optionally, in the delivery sheath described above, a variable-diameter tube segment for transition is connected between the variable-diameter delivery sheath proximal tube segment and the variable-diameter delivery sheath distal tube segment.

[0014] Optionally, in the delivery sheath described above, a transition structure is arranged at the proximal end of the sliding blocking member, and at a second limit position of the sliding of the sliding blocking member, the transition structure is located in the variable-diameter tube segment.

[0015] Optionally, in the delivery sheath described above, the sliding blocking member is limited to the first limit position of the sliding in the variable-diameter delivery sheath distal tube segment by a limiting rope cable.

[0016] One end of the limiting rope cable is connected to the variable-diameter tube segment, and the other end is connected to the proximal end of the sliding blocking member.

[0017] Optionally, in the delivery sheath described above, the limiting rope cable is a plurality of ones connected to the sliding blocking member.

[0018] Optionally, in the delivery sheath described above, the sliding blocking member is made of silicone, TPU or PEBAX.

[0019] Alternatively, the sliding blocking member is a blocking stent made of nickel-titanium alloy.

[0020] Optionally, in the delivery sheath described above, the variable-diameter delivery sheath distal tube segment is switchable between a contracted state and an expanded state.

[0021] When the variable-diameter delivery sheath distal tube segment is in the contracted state, the tube diameter of the variable-diameter delivery sheath distal tube segment is equal to the tube diameter of the variable-diameter delivery sheath proximal tube segment, for accommodating the interventional catheter.

[0022] When the variable-diameter delivery sheath distal tube segment is in the expanded state, the tube diameter of the variable-diameter delivery sheath distal tube segment is greater than the tube diameter of the variable-diameter delivery sheath proximal tube segment, for accommodating the pump head.

[0023] Optionally, in the delivery sheath described above, the variable-diameter delivery sheath distal tube segment comprises:

[0024] a delivery sheath elastic tube body having an opening in the axial direction, the opening of the delivery sheath elastic tube body being open when the pump head is folded into the variable-diameter delivery sheath distal tube segment, the variable-diameter delivery sheath distal tube segment being in the expanded state; after the pump head is released from the variable-diameter delivery sheath distal tube segment, the catheter walls on both sides of the opening of the delivery sheath elastic tube body overlap, and the variable-diameter delivery sheath distal tube segment is in the contracted state.

[0025] a retractable inner membrane connected to both ends of the opening of the delivery sheath elastic tube body.

[0026] An interventional blood pump delivery system, comprising:

[0027] a delivery sheath, which is the delivery sheath described above;

[0028] a tearable interventional sheath, wherein the delivery sheath is used to pass through the tearable interventional sheath.

[0029] The delivery sheath provided by the present application is used for delivering an interventional blood pump. The interventional blood pump comprises an interventional catheter and a pump head connected in a proximal-to-distal direction. The pump head can be folded into the delivery sheath after being compressed, and the maximum outer diameter of the pump head after being folded is still greater than the outer diameter of the interventional catheter. The delivery sheath comprises a variable-diameter delivery sheath and a sliding blocking member. The variable-diameter delivery sheath comprises a variable-diameter delivery sheath proximal tube segment and a variable-diameter delivery sheath distal tube segment connected in a proximal-to-distal direction. The tube diameter of the variable-diameter delivery sheath distal tube segment is greater than the tube diameter of the variable-diameter delivery sheath proximal tube segment. The variable-diameter delivery sheath proximal tube segment is used for accommodating the interventional catheter, and the variable-diameter delivery sheath distal tube segment is used for accommodating the pump head.

[0030] After the pump head of the interventional blood pump is folded into the variable-diameter delivery sheath distal tube segment, the interventional blood pump and the delivery sheath are inserted into the tearable interventional sheath which has been inserted into the blood vessel of the patient. After the delivery sheath enters the blood vessel, the tearable interventional sheath is pulled out from the puncture port, and the tearable interventional sheath is torn off from the delivery sheath outside the body. At this time, the variable-diameter delivery sheath proximal tube segment with a smaller outer diameter is located at the puncture port, so that the puncture port maintains a smaller pore diameter.

[0031] Compared with the prior art, the diameter change of the delivery sheath in the axial direction can be used to smoothly place the interventional blood pump with inconsistent outer diameters in the working position in the heart chamber, realize the delivery of the interventional blood pump, and maintain the puncture port at a smaller size through the variable-diameter delivery sheath proximal tube segment with a smaller diameter when the interventional blood pump provides long-term cardiac assistance, thereby reducing the pain of the patient, accommodating the pump head through the variable-diameter delivery sheath distal tube segment with a larger diameter, facilitating the release of the pump head, and reducing the damage probability of the pump head during folding.

[0032] The interventional blood pump delivery system provided by the present application comprises the delivery sheath and the tearable interventional sheath, and the delivery sheath is used to pass through the tearable interventional sheath. Due to the interventional blood pump delivery system, the same structure and beneficial effects are also achieved, and details are not repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0034] Figure 1 It is a structural schematic diagram of an interventional blood pump in the prior art;

[0035] Figure 2 It is a structural schematic diagram of the delivery sheath disclosed in the embodiment of the present application;

[0036] Figure 3 It is a schematic diagram of the delivery sheath disclosed in the embodiment of the present application inserted into the tearable interventional sheath state;

[0037] Figure 4 It is a schematic diagram of the delivery sheath disclosed in the embodiment of the present application after the blood pumping catheter is folded and enters the tearable interventional sheath;

[0038] Figure 5 It is a schematic diagram of the delivery sheath disclosed in the embodiment of the present application when the blood pumping catheter is in the working state;

[0039] Figure 6The position diagram of the sliding blocking piece when the interventional blood pump is sheathed is disclosed in the embodiment of the present application.

[0040] Figure 7 The position diagram of the sliding blocking piece after the interventional blood pump is released is disclosed in the embodiment of the present application.

[0041] Figure 8 The structural diagram of the variable-diameter delivery sheath when the distal tube segment is in a contracted state is disclosed in the embodiment of the present application.

[0042] Figure 9 The structural diagram of the variable-diameter delivery sheath when the distal tube segment is in an expanded state is disclosed in the embodiment of the present application.

[0043] In the figure, 100 is an interventional blood pump, 110 is a handle, 120 is an interventional catheter, 130 is a motor, 140 is a blood pumping catheter, 150 is an inlet protection stent, and 160 is a pigtail catheter.

[0044] 200 is a delivery sheath, 201 is a gland, 202 is a delivery sheath joint, 203 is a suture pad, 204 is an exhaust catheter, 205 is a three-way valve, 210 is a variable-diameter delivery sheath, 211 is a proximal tube segment of the variable-diameter delivery sheath, 212 is a variable-diameter tube segment, 213 is a distal tube segment of the variable-diameter delivery sheath, 220 is a sliding blocking piece, 221 is a limiting rope cable, 222 is a distal connecting point of the limiting rope cable, 223 is a proximal connecting point of the limiting rope cable, 231 is a retractable inner membrane, and 232 is a delivery sheath elastic tube body.

[0045] 300 is a tearable interventional sheath. DETAILED DESCRIPTION

[0046] The core of the present application is to disclose a delivery sheath for smoothly placing blood pump catheters with inconsistent outer diameters in the working position in the heart chamber, while maintaining the puncture port at a smaller size when the blood pump provides long-term cardiac assistance.

[0047] Another core of the present application is to disclose an interventional blood pump delivery system, which includes the above-mentioned delivery sheath.

[0048] Hereinafter, the embodiments will be described with reference to the accompanying drawings. Furthermore, the embodiments shown below do not have any limiting effect on the invention content recited in the claims. In addition, the entire contents of the configurations represented in the following embodiments are not limited to what is necessary as a solution to the invention recited in the claims.

[0049] In the description of the embodiments of the present application, unless otherwise specified, " / " represents the meaning of or, for example, A / B can represent A or B; "and / or" herein is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist together, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0050] Hereinafter, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features.

[0051] The delivery sheath 200 disclosed in the embodiments of the present application is used to deliver the interventional blood pump 100, which is combined with Figure 1 The interventional blood pump 100 includes an interventional catheter 120 and a pump head connected in the direction from the proximal end to the distal end, and the pump head can be folded into the delivery sheath 200 after being compressed, and the maximum outer diameter of the pump head after being folded is still greater than the outer diameter of the interventional catheter 120. Wherein, the pump head refers to all structures including the motor 130, the blood pump catheter 140, the inlet protection bracket 150 and the pigtail catheter 160.

[0052] The delivery sheath 200 includes a variable-diameter delivery sheath 210 and a sliding blocking piece 220. The variable-diameter delivery sheath 210 includes a variable-diameter delivery sheath proximal pipe segment 211 and a variable-diameter delivery sheath distal pipe segment 213 connected in the direction from the proximal end to the distal end, the pipe diameter of the variable-diameter delivery sheath distal pipe segment 213 is greater than the pipe diameter of the variable-diameter delivery sheath proximal pipe segment 211, the variable-diameter delivery sheath proximal pipe segment 211 is used to accommodate the interventional catheter 120, and the variable-diameter delivery sheath distal pipe segment 213 is used to accommodate the pump head.

[0053] Combined with Figure 3 After the pump head of the interventional blood pump 100 is folded into the variable-diameter delivery sheath distal pipe segment 213, the interventional blood pump 100 and the delivery sheath 200 are inserted into the tearable interventional sheath 300 which has been inserted into the blood vessel of the patient. The delivery sheath 200 is pulled out of the tearable interventional sheath 300 from the puncture port after entering the blood vessel, and the tearable interventional sheath 300 is torn off from the delivery sheath 200 outside the body, at this time, the variable-diameter delivery sheath proximal pipe segment 211 with smaller outer diameter is at the puncture port, so that the puncture port maintains a smaller pore diameter.

[0054] Compared with the prior art, the diameter change of the delivery sheath 200 in the axial direction can be used to smoothly place the interventional blood pump 100 with inconsistent outer diameters in the working position in the heart chamber, realize the delivery of the interventional blood pump 100, and when the interventional blood pump 100 provides cardiac assistance for a long time, the smaller-diameter variable-diameter delivery sheath proximal tube segment 211 keeps the puncture port at a smaller size, reduces the pain of the patient, the larger-diameter variable-diameter delivery sheath distal tube segment 213 accommodates the pump head, facilitates the release of the pump head, and reduces the damage probability of the pump head when being folded.

[0055] It should be noted that the following blood pump catheter refers to all structures including the interventional catheter 120, the motor 130, the blood pumping catheter 140, the inlet protection bracket 150, and the pigtail catheter 160.

[0056] When the pump head end (hereinafter referred to as the blood pump head end) of the interventional blood pump 100 is released from the delivery sheath 200, a larger gap exists between the inner wall of the variable-diameter delivery sheath distal tube segment 213 and the outer wall of the interventional catheter 120 at this time, and blood entering the gap and staying in the gap can cause blood clotting. In order to avoid the blood clotting phenomenon, in a specific embodiment disclosed in the present application, the delivery sheath 200 further comprises a sliding sealing member 220.

[0057] The sliding sealing member 220 is slidably arranged in the variable-diameter delivery sheath distal tube segment 213, is used for sealing connection between the interventional catheter 120 and the variable-diameter delivery sheath distal tube segment 213, and at a first limit position of the sliding of the sliding sealing member 220, the distal end face of the sliding sealing member 220 is flush with the end face of the distal end of the variable-diameter delivery sheath distal tube segment 213, so as to avoid the blood entering the variable-diameter delivery sheath distal tube segment 213.

[0058] The sliding sealing member 220 can seal the gap between the interventional catheter 120 and the variable-diameter delivery sheath distal tube segment 213, and the sliding of the sliding sealing member 220 can make the sliding sealing member 220 slide to the distal end opening of the variable-diameter delivery sheath distal tube segment 213, so as to seal the blood outside the variable-diameter delivery sheath distal tube segment 213, and make the blood not flow back to the delivery sheath 200 to stay and cause blood clotting.

[0059] The inner diameter of the sliding sealing member 220 is slightly greater than or equal to the outer diameter of the interventional catheter 120, and the outer diameter is slightly less than or equal to the inner diameter of the variable-diameter delivery sheath distal tube segment 213.

[0060] In combination Figure 2 The inner diameter of the variable-diameter delivery sheath proximal tube segment 211 is slightly greater than the outer diameter of the interventional catheter 120, so that there is basically no gap between the two, and after physiological saline is injected through the exhaust catheter 204, the blood will not enter the gap.

[0061] A transition tube segment 212 is connected between the proximal tube segment 211 and the distal tube segment 213 of the variable diameter delivery sheath for transition.

[0062] In combination Figure 6 The proximal end of the sliding blocking member 220 is provided with a transition structure, and at the second limit position of the sliding of the sliding blocking member 220, the transition structure is located in the transition tube segment 212. The blood pump is folded in the lumen of the distal tube segment 213 of the variable diameter delivery sheath, and the blood pump is folded to push the sliding blocking member 220 to the second limit position due to the size limitation of the transition tube segment 212.

[0063] In a specific embodiment disclosed in the present application, the sliding blocking member 220 is limited to the first limit position of the sliding in the distal tube segment 213 of the variable diameter delivery sheath by the limiting rope cable 221.

[0064] In the initial state of the delivery sheath 200 input into the blood vessel, the sliding blocking member 220 is located at the initial position / second limit position and at the proximal end of the motor 130, in combination Figure 7 When the blood pump head end is released from the interventional sheath and moves along the delivery sheath 200, the sliding blocking member 220 first slides with the interventional catheter 120 in the distal tube segment 213 of the variable diameter delivery sheath until it is limited to the first limit position by the limiting rope cable 221.

[0065] In combination Figure 5 One end (limiting rope cable proximal end connection point 223) of the limiting rope cable 221 is connected to the transition tube segment 212, and the other end (limiting rope cable distal end connection point 222) is connected to the proximal end of the sliding blocking member 220. The structure of the transition tube segment 212 can accommodate the limiting rope cable 221 made of flexible wire.

[0066] Specifically, the transition tube segment 212 is generally composed of an inner layer of PTFE structure, an intermediate layer of stainless steel spring or woven mesh, and an outer layer of PEBAX or TPU structure, and the limiting rope cable 221 is generally connected with the stainless steel spring or woven mesh structure of the intermediate layer of the transition tube segment 212.

[0067] In combination Figures 4-7 When the blood pump head end is released from the delivery sheath 200 to assist the heart, due to the force of the interventional catheter 120 pushing the distal tube segment 213 of the variable diameter delivery sheath to the distal end, the sliding blocking member 220 slides from the position in the transition tube segment 212 when folded (second limit position) to the position of the distal outlet of the distal tube segment 213 of the variable diameter delivery sheath (first limit position), at which time the limiting rope cable 221 is in a taut state, the limiting rope cable 221 limits the sliding of the sliding blocking member 220 to the outside of the distal tube segment 213 of the variable diameter delivery sheath, and avoids being pulled out from the inside of the distal tube segment 213 of the variable diameter delivery sheath.

[0068] Among them, Figure 7The blood pump catheter is shown in the state of being folded into the sheath before or after the blood pump is released, which is also the shaping state of the delivery sheath 200 when it is made.

[0069] During the sliding of the sliding blocking member 220 from the second limit position to the first limit position, physiological saline can be perfused between the variable-diameter delivery sheath distal tube segment 213 and the interventional catheter 120 to promote the sliding of the sliding blocking member 220.

[0070] During the preparation of the delivery sheath 200, the limiting rope 221 can be fixed to the variable-diameter tube segment 212 and the sliding blocking member 220 before the variable-diameter tube segment 212 and the variable-diameter delivery sheath distal tube segment 213 are connected, and then the variable-diameter tube segment 212 and the variable-diameter delivery sheath distal tube segment 213 are connected, and the variable-diameter tube segment 212 and the variable-diameter delivery sheath proximal tube segment 211 are connected.

[0071] Among them, the limiting rope 221 is connected with the sliding blocking member 220, and the limiting rope 221 can be uniformly arranged along the circumference of the sliding blocking member 220, or two symmetrically arranged on the sliding blocking member 220.

[0072] The sliding of the sliding blocking member 220 in the variable-diameter delivery sheath distal tube segment 213 can also be realized by other structures, for example, a limiting portion is arranged at the distal end opening of the variable-diameter tube segment 212, which can be passed through by the interventional blood pump 100, but the sliding blocking member 220 will be limited by the limiting portion and cannot be pulled out from the variable-diameter delivery sheath distal tube segment 213. But this scheme will cause the outer diameter of the variable-diameter delivery sheath distal tube segment 213 to expand to a certain extent, thereby causing the size of the tearable interventional sheath 300 to expand, which will increase the size of the puncture port and cause more pain to the patient.

[0073] The sliding blocking member 220 can be made of flexible materials such as medical-grade materials such as silicone, TPU (thermoplastic polyurethane elastomer rubber), PEBAX (nylon elastomer), etc. The sliding blocking member 220 can also be a blocking stent shaped by nickel-titanium alloy, or a blocking stent woven by nickel-titanium alloy wire. The inner diameter of the blocking stent is slightly larger than the outer diameter of the interventional catheter 120, and the radial support force of the blocking stent can automatically fit the inner wall of the variable-diameter delivery sheath distal tube segment 213 without affecting the blocking effect.

[0074] In combination with Figure 8 and Figure 9In another specific embodiment of the present disclosure, the variable diameter delivery sheath distal tube segment 213 can switch between a contracted state and an expanded state. When the variable diameter delivery sheath distal tube segment 213 is in the contracted state, the diameter of the variable diameter delivery sheath distal tube segment 213 is equal to or slightly larger than the diameter of the variable diameter delivery sheath proximal tube segment 211, for fitting with the outer wall of the interventional catheter 120 and accommodating the interventional catheter 120. When the variable diameter delivery sheath distal tube segment 213 is in the expanded state, the diameter of the variable diameter delivery sheath distal tube segment 213 is larger than the diameter of the variable diameter delivery sheath proximal tube segment 211, for fitting with the outer wall of the pump head and accommodating the pump head.

[0075] The delivery sheath 200 disclosed in the embodiments of the present disclosure is a variable diameter catheter that can be radially expanded and contracted, so that it can be used to deliver the interventional blood pump 100 with the motor 130 built-in and the pump head being radially foldable. The switching of the variable diameter delivery sheath distal tube segment 213 between the contracted state and the expanded state can ensure that it is always in contact with the outer wall of the interventional blood pump 100, so as to block the blood outside the delivery sheath 200 and avoid the occurrence of blood clotting.

[0076] Specifically, the variable diameter delivery sheath distal tube segment 213 includes a delivery sheath elastic tube body 232 and a retractable inner membrane 231. The delivery sheath elastic tube body 232 has an opening in the axial direction. When the pump head is folded in the variable diameter delivery sheath distal tube segment 213, the opening of the delivery sheath elastic tube body 232 is open, and the variable diameter delivery sheath proximal tube segment 211 is in the expanded state. After the pump head is released from the variable diameter delivery sheath distal tube segment 213, the catheter walls on both sides of the opening of the delivery sheath elastic tube body 232 are partially overlapped, and the variable diameter delivery sheath proximal tube segment 211 is in the contracted state. The variable diameter delivery sheath distal tube segment 213 can switch between the contracted state and the expanded state through the delivery sheath elastic tube body 232. The retractable inner membrane 231 is retractably connected to both ends of the opening of the delivery sheath elastic tube body 232, so as to retract and expand with the variable diameter delivery sheath distal tube segment 213 switching between the contracted state and the expanded state, and form a complete tube side wall with the delivery sheath elastic tube body 232.

[0077] The variable diameter delivery sheath distal tube segment 213 is expanded to the expanded state by the radial force of the blood pump head end. After the blood pump head end is released from the delivery sheath 200, the variable diameter delivery sheath distal tube segment 213 has a self-induced inward contraction radial force, and returns to the folded state as shown. Figure 8 At this time, the inner wall of the delivery sheath elastic tube body 232 is in close contact with the outer wall of the interventional catheter 120, and the inner diameters of the variable diameter delivery sheath proximal tube segment 211 and the variable diameter delivery sheath distal tube segment 213 are almost consistent, so as to greatly reduce the gap between the delivery sheath 200 and the interventional catheter 120.

[0078] The elastic tube body 232 of the delivery sheath is made of a high polymer material with elasticity, and the inner membrane 231 is a PTFE (polytetrafluoroethylene) inner membrane.

[0079] The delivery sheath 200 further comprises a delivery sheath connector 202, a gland 201, and a suture pad 203, etc. The delivery sheath connector 202 is connected to the proximal end of the variable-diameter delivery sheath proximal tube segment 211, and is connected with a three-way valve 205 through an exhaust conduit 204. The gland 201 is connected to the proximal end of the delivery sheath connector 202, and the suture pad 203 is arranged on the outer wall of the delivery sheath connector 202. This is the prior art, and will not be described here.

[0080] The interventional blood pump delivery system disclosed in the embodiments of the present application comprises the delivery sheath 200 and the tearable interventional sheath 300, and the delivery sheath 200 is used to pass through the tearable interventional sheath 300. Since the interventional blood pump delivery system has the above-mentioned structure and beneficial effects, it will not be described here.

[0081] The tearable interventional sheath 300 can be removed after the delivery sheath 200 enters the blood vessel, and is torn along the axial direction by using the tearable sheath handle and is peeled off from the delivery sheath 200.

[0082] The terms "first" and "second" and the like in the specification and claims of the present application are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can include steps or units not listed.

[0083] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

[0084] The description above only clearly and completely describes preferred embodiments of the present application and the technical principles of the application, and is not used to limit the application. Those skilled in the art can make various modifications and variations to the application. The application scope involved in the application is not limited to the technical solutions formed by the specific combinations of the above technical features, and should also cover other technical solutions formed by the combinations of the above technical features or equivalent features without departing from the above application concept. For example, the technical solutions formed by the mutual replacement of the above features and the technical features disclosed in the application (but not limited to) having similar functions.

Claims

1. A delivery sheath for delivering an interventional blood pump (100), wherein the interventional blood pump (100) comprises, from the proximal end to the distal end, an interventional catheter (120) and a pump head connected thereto, wherein the pump head is foldable, and the maximum outer diameter after folding is greater than the outer diameter of the interventional catheter (120), and wherein: including a variable diameter delivery sheath (210); The variable diameter delivery sheath (210) includes a variable diameter delivery sheath proximal tube section (211) and a variable diameter delivery sheath distal tube section (213) connected from the proximal end to the distal end, the diameter of the variable diameter delivery sheath distal tube section (213) is larger than the diameter of the variable diameter delivery sheath proximal tube section (211), the variable diameter delivery sheath proximal tube section (211) is used to accommodate the interventional catheter (120), and the variable diameter delivery sheath distal tube section (213) is used to accommodate the pump head; It also includes a sliding sealing member (220), which can be slidably arranged in the distal end tube section (213) of the variable diameter delivery sheath, and is used to seal the connection between the interventional catheter (120) and the distal end tube section (213) of the variable diameter delivery sheath. At the first extreme sliding position of the sliding sealing member (220), the distal end face of the sliding sealing member (220) is flush with the distal end face of the distal end of the distal end tube section (213) of the variable diameter delivery sheath.

2. The delivery sheath according to claim 1, wherein A variable diameter pipe section (212) for transition is connected between the proximal pipe section (211) of the variable diameter delivery sheath and the distal pipe section (213) of the variable diameter delivery sheath.

3. The delivery sheath according to claim 2, wherein: A transition structure is provided at the proximal end of the sliding sealing member (220), and at the second extreme sliding position of the sliding sealing member (220), the transition structure is located within the reducing pipe section (212).

4. The delivery sheath according to claim 2, wherein: The sliding blocking member (220) is limited to a first limit position of sliding in the distal end tube section (213) of the variable diameter delivery sheath by a limiting cable (221); One end of the position-limiting cable (221) is connected to the reducing pipe section (212), and the other end is connected to the proximal end of the sliding blocking member (220).

5. The delivery sheath according to claim 4, wherein: The limiting cables (221) are multiple cables connected to the sliding blocking member (220).

6. The delivery sheath according to claim 1, wherein: The sliding sealing member (220) is made of silicone, TPU or PEBAX; Alternatively, the sliding sealing member (220) is a sealing stent made of nickel-titanium alloy.

7. An interventional blood pump delivery system, characterized in that: include: The delivery sheath (200) is the delivery sheath according to any one of claims 1 to 6; A tearable intervention sheath (300) is provided, and the delivery sheath (200) is used to pass through the tearable intervention sheath (300).

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