An interventional heart valve delivery device

Abstract

This invention discloses an interventional heart valve delivery device, comprising a core tube assembly, a guide head and a fixing head fixed on the core tube assembly, wherein the guide head is fixed at the distal end of the core tube assembly, and the fixing head extends from the proximal end of the core tube assembly, with the interventional heart valve installation position located between the guide head and the fixing head; an axially slidable outer sheath is provided around the interventional heart valve installation position, and a floating limiting strip is also provided, the proximal end of which is a starting end fixed relative to the fixing head or the core tube assembly, and the floating limiting strip floats between the interventional heart valve installation position and the outer sheath; the outer wall of the fixing head is provided with a positioning part for cooperating with the connecting ear of the interventional heart valve; when the interventional heart valve is loaded, the distal end of the floating limiting strip axially overlaps at least on the connecting ear, and upon release, as the outer sheath retracts, the floating limiting strip can swing freely and release the radial pressure on the connecting ear.

Description

[0001] This application is a divisional application. The original application has the application number "201810509256.3", the application date is "May 24, 2018", and the invention title is "A delivery device for repositioning interventional heart valves". Technical Field

[0002] This invention relates to the field of medical devices, and more specifically, to a delivery device for implanting an artificial heart valve into the heart. Background Technology

[0003] Heart valve disease is one of the most common heart diseases, primarily caused by valvular damage due to rheumatic fever. In recent years, degenerative changes in valves (including calcification and myxoid degeneration) and metabolic disorders causing valvular damage have also become increasingly common. Furthermore, congenital valvular disease is also a common cause of heart disease. Many high-risk patients with heart valve disease, such as those with severe valvular regurgitation, elderly patients unsuitable for surgical valve replacement, and patients with advanced tumors and valvular regurgitation, require new, minimally invasive interventional methods. Interventional heart valve surgery was developed inspired by surgical heart valve replacement procedures. In recent years, percutaneous valve intervention has emerged and has been successfully applied in humans since 2000. From experimental research to small-scale parallel clinical trials, interventional valvular disease may overcome technical bottlenecks and rapidly achieve widespread clinical application, once again becoming a focus of attention in the field of interventional cardiology.

[0004] In the existing technology, after the artificial heart valve stent is compressed, it is delivered into the human body through a delivery device. The compressed valve stent is usually elastic, and when it is compressed, it exerts a great force on the compression catheter. This excessive force makes it difficult for the valve stent to be released slowly and precisely, often resulting in excessive friction between the valve stent and the inner wall of the blood vessel.

[0005] Chinese patent document CN101953725 discloses an artificial heart valve stent, comprising an aortic stent, a valve stent, an outflow tract stent, and a connecting lug. When the heart valve is compressed into the delivery device, the connecting lug engages with the stent fixing assembly of the delivery device. During the release of the valve stent, the slow release of the valve stent is achieved through the engagement of the connecting lug and the contraction of the outer sheath. However, in the prior art, the contraction force of the connecting lug of the valve stent is relatively small. In the later stages of the valve stent release process, the connecting lug is very easy to pop out of the stent fixing assembly of the delivery device, causing the valve stent to be completely released. At this time, if problems such as positioning deviation are found, it is impossible to retrieve it in time, and surgical replacement is the only option.

[0006] To overcome the aforementioned problems during the release of valvular stents after implantation, US Patent 5683451 discloses a delivery device and method for controlled release of valvular stents. By setting a track within the delivery device, the frictional force caused by elastic expansion of the delivery catheter during the delivery and release of the valvular prosthesis is reduced. This invention reduces friction between the valvular stent and the delivery catheter. However, the problem of sudden and complete release of the valvular stent due to excessive elasticity during release remains unresolved. Once released, the valvular stent cannot be repositioned or repositioned, which not only requires extremely high precision during surgery but also poses certain risks.

[0007] Furthermore, existing delivery sheaths for interventional cardiac valves are mostly made of polymer materials. While polymers offer good performance properties, their elasticity and strength are relatively poor. Currently, some methods incorporate reinforcing materials into polymers, such as braided mesh tubes or elastic tubes, to form an outer sheath by coating the reinforcing tube with polymer material. However, these measures only increase the sheath's resistance to bending and pressure; they do not significantly solve the problems encountered during the retraction of the interventional cardiac valve, such as difficulty in retrieving the valve and sheath wrinkling. Summary of the Invention

[0008] This invention provides a repositionable delivery device for interventional heart valves, which can secure the last released end of the valve stent during the release of the interventional heart valve, preventing the interventional heart valve from suddenly dislodging from the installation position before release confirmation or during further retraction and adjustment of the valve position. At the same time, the outer sheath can provide stable axial support and expansion force during the retrieval of the interventional heart valve, so as to achieve stable and easy repositioning of the interventional heart valve.

[0009] An interventional heart valve repositioning delivery device includes a core tube assembly, on which a guide head and a fixation head are fixed. The guide head is fixed at the distal end of the core tube assembly, and the fixation head extends from the proximal end of the core tube assembly. The space between the guide head and the fixation head is an interventional heart valve installation position. An axially sliding outer sheath is provided around the interventional heart valve installation position.

[0010] It is also equipped with a floating limiting strip, the proximal end of which is the starting end fixed relative to the fixed head or core tube assembly, and the floating limiting strip floats between the interventional heart valve installation position and the outer sheath.

[0011] The outer wall of the fixing head is provided with a positioning part for engaging with the connecting ear of the interventional heart valve. Before the connecting ear is completely released from the outer sheath, the floating limiting strip is bound by the outer sheath to maintain the engagement between the connecting ear and the positioning part.

[0012] The outer sheath tube comprises an inner layer, a middle layer and an outer layer from the inside out. The middle layer comprises a first segment, a second segment and a third segment from the distal end to the proximal end. The first segment is a hollow structure, which includes at least two hollow units. Two adjacent hollow units are separated from each other at the distal end of the first segment in the circumferential direction.

[0013] In this invention, the floating limiting strip is located between the outer sheath and the interventional heart valve, effectively filling the radial gap between the outer sheath and the connecting lug of the interventional heart valve. This strengthens and reinforces the radial tightening force of the outer sheath on the connecting lug, enhancing the stability and firmness of the connection between the connecting lug and the fixing head. This prevents the connecting lug from detaching from the fixing head and becoming uncontrollable before the interventional heart valve is fully released. Furthermore, in cases where valve release is not ideal, it provides a strong and stable pulling force for the interventional valve to be pulled back into the outer sheath for secondary positioning or retraction. Simultaneously, the inner middle layer of the outer sheath not only enhances the axial support force of the outer sheath but also allows for radial expansion, promoting radial contraction of the valve and reducing resistance during retraction. In other words, it ensures stable pulling force on the valve on one hand and reduces resistance to the retraction of the released portion of the valve back into the outer sheath on the other, effectively and safely achieving the delivery, release, and repositioning of the interventional heart valve.

[0014] The floating limit bar can swing freely relative to the interventional heart valve or core tube assembly when the valve is not loaded or when there is no external sheath restraint, or it can maintain its relative position and posture solely by the strength of its own material.

[0015] Before the interventional heart valve is fully released from the outer sheath after being loaded into it, the floating limiting strip is bound by the outer sheath to maintain the fit between the connecting ear and the positioning part. As the outer sheath retracts and the connecting ear is gradually released, the floating limiting strip is also gradually released from the outer sheath. When the connecting ear is fully released and detached from the fixing head, the floating limiting strip can swing freely. The released floating limiting strip no longer applies radial clamping force to the connecting ear. That is, after confirming that the interventional heart valve is in good position, the outer sheath will continue to retract, releasing the connecting ear and the floating limiting strip. At this time, the floating limiting strip released from the outer sheath no longer has a limiting effect on the connecting ear and will not cause secondary interference to the interventional heart valve, leading to displacement of the interventional heart valve.

[0016] After the interventional heart valve is loaded into the outer sheath, the floating limiting strip also acts as a shim, compensating for the fit tolerance between the outer sheath and the connecting ear of the interventional heart valve, and filling the radial gap between the outer sheath and the connecting ear of the interventional heart valve. The floating limiting strip has a simple structure, and filling the gap will not increase the radial dimension of the delivery system during valve implantation; it strengthens and enhances the connection fit between the existing interventional valve and the fixation head, making the connection performance more stable; the radial pressure of the floating limiting strip on the connecting ear disappears synchronously with the retraction of the outer sheath, and will not cause new interference to the valve that has been properly released.

[0017] In this invention, the interventional heart valve installation position is used to install an interventional artificial heart valve. The length of the interventional heart valve installation position should be adapted to the length of the interventional artificial heart valve stent. The interventional heart valve installation position includes not only the entire section between the guide head and the fixation head, but also the portion extending from the distal end of the fixation head to the fixation head positioning part.

[0018] Preferably, the starting end of the floating limit bar is fixed to at least one of the fixed head or the core tube assembly.

[0019] The fixed position of the starting end of the floating limiting strip is close to the fixing head, for example, at the tail end of the fixed head (along the direction of the delivery device towards the operator) or on the core tube assembly connected to the tail end. Before the operation, the interventional heart valve and the floating limiting strip are gathered through the outer sheath, so that the floating limiting strip is radially converging inward and abutting against the outer periphery of the interventional heart valve. During the release process after the interventional heart valve enters the body, the floating limiting strip is radially outward as the outer sheath is retracted and the valve stent is released.

[0020] To control the axial position of the interventional heart valve, a connecting ear that mates with the fixing head is generally provided at the proximal end of the interventional heart valve. The connecting ear can generally be T-shaped, L-shaped, or ring-shaped, etc. The positioning part can be a positioning groove that receives the T-shaped or L-shaped part, or a protrusion that snaps into the ring, etc., so that the axial position of the interventional heart valve is restricted by the positioning part after the valve is loaded. In this invention, the shape of the connecting ear itself can adopt the existing technology, which is not the focus of the improvement of this invention.

[0021] Preferably, the positioning part is a positioning protrusion. After the valve is loaded, the connecting ear is fitted onto the positioning protrusion. Before the connecting ear is completely released from the outer sheath, the floating limiting strip is superimposed on the connecting ear to maintain the fit between the connecting ear and the positioning part.

[0022] Preferably, the positioning part is a positioning groove. After the valve is loaded, the connecting ear is embedded in the corresponding positioning groove. Before the connecting ear is completely released from the outer sheath, the floating limiting strip is superimposed on the connecting ear to maintain the fit between the connecting ear and the positioning part.

[0023] For example, when a positioning groove is used, the connecting ear is inserted into the positioning groove during valve loading to achieve axial positioning. After the outer sheath is removed, the connecting ear moves radially outward from the positioning groove along the support.

[0024] When using a positioning groove, a protruding head structure can also be combined, that is, a protruding head is set at the bottom of the positioning groove, which, together with the corresponding shape of the connecting ear, can enhance the positioning effect.

[0025] Preferably, the number of floating limit bars and positioning slots are the same, and their circumferential positions correspond one-to-one.

[0026] The positioning groove ensures that the floating limit bar will not shift during the retraction and release process.

[0027] After valve loading, the proximal end of the floating limiting strip is tightly secured to the positioning groove and the embedded connecting ear under the outer sheath. During the release of the valve stent by retracting the outer sheath, the floating limiting strip's compression and securing action within the positioning groove prevents rapid release and dislodgement of the valve stent. If positioning deviation is detected during stent release, the outer sheath can be pushed forward to compress and retrieve the released stent. At this time, the connecting ear is tightly wrapped by the floating limiting strip and the outer sheath, effectively ensuring safe control and secondary positioning of the valve stent.

[0028] Preferably, the end of the floating limiting strip extends at least to a position corresponding to the connecting ear. That is, it at least covers part of the connecting ear to restrain the radial movement of the connecting ear. Furthermore, the end of the floating limiting strip can extend further distally.

[0029] The end of the floating limit bar is relative to the starting end; the end can also be understood as the far end of the floating limit bar.

[0030] Preferably, the farthest end of the floating limit bar is aligned with or does not exceed the farthest end of the fixed head, or slightly exceeds the farthest end of the fixed head.

[0031] When the floating limiting strip has its minimum length, it can at least cover the connecting ear. To further ensure the clamping effect, the end of the floating limiting strip can extend further to the distal end of the fixing head or slightly beyond the distal end of the fixing head, for example, by a length less than or equal to 1 cm. When the floating limiting strip has its maximum length, the entire floating limiting strip can be contained within the outer sheath, and the end of the floating limiting strip is flush with the distal end of the valve stent inside the outer sheath. At this time, the length of the floating limiting strip can wrap around the entire valve stent, and the floating limiting strip acts as a slide rail, ensuring that the outer sheath can be pushed forward and retracted along the slide rail without directly contacting the valve stent.

[0032] After the interventional heart valve is loaded, the floating limiting strip is restrained by the outer sheath, which restricts the connecting lug within the positioning groove. The inner wall of the outer sheath contacts the floating limiting strip and provides radial restraint. The floating limiting strip can block the connecting lug within the positioning groove to prevent it from dislodging.

[0033] Preferably, the positioning groove is axially continuous, and the part of the floating limiting strip that mates with the positioning groove is partially or completely submerged in the positioning groove.

[0034] The floating limiting strip extends distally through the positioning groove. The positioning groove is not only axially continuous but also open radially outward, i.e., it has a radial opening. The floating limiting strip is not strictly limited to being completely inside the radial opening; it is allowed to be partially outside the radial opening. For example, the floating limiting strip has a T-shaped cross-section. The bottom end of the T-shape extends into the positioning groove to block the connecting lug, while the top dimension of the T-shape is limited by the radial opening and is therefore located outside the radial opening. This ensures both the fit with the inner wall of the outer sheath and the fit with the connecting lug.

[0035] Preferably, the axial through area of ​​the positioning groove is closed by a floating limiting strip.

[0036] To prevent the connecting lugs from coming off, the width of the floating limit strip can be the same as or slightly wider than the radial opening of the axial through area, so as to completely close the radial opening. Even if the width is less than the width of the radial opening, the gap will at least prevent the connecting lugs from coming off. The width of the floating limit strip is preferably the same as the radial opening of the axial through area, which can further prevent the floating limit strip from shifting.

[0037] Preferably, the portion of the floating limiting strip that sinks into the positioning groove contacts or abuts against the connecting ear in the radial direction.

[0038] Although the floating limiting strip can block the connecting lug, the thickness (radial dimension) of the two and the depth of the positioning groove can have different matching relationships. When the outer sheath covers the outer periphery of the contact fixing head, the floating limiting strip is stacked on the outer wall of the connecting lug. If the sum of the thickness of the floating limiting strip and the connecting lug is greater than the depth of the positioning groove, the floating limiting strip presses against the connecting lug in the radial direction. Otherwise, it only makes contact and does not generate a significant tightening force, but it can still ensure the limiting of the floating limiting strip and the connecting lug. As a further preferred option, the pressing relationship can ensure that the limiting is maintained even when the axial force is too large or the outer sheath is locally deformed.

[0039] Preferably, after the valve is loaded, the floating limiting strip is at the same height as or higher than the outer wall of the fixing head in the radial direction.

[0040] The floating limit strip is not lower than the outer wall of the fixed head in the radial direction, which can avoid unnecessary gaps between the floating limit strip and the inner wall of the outer sheath tube, so that the inner wall of the outer sheath tube is tightly attached to the floating limit strip and the connecting lug is pressed into the positioning part of the fixed head.

[0041] Optionally, the floating limit strip extends along a straight line or curve at the part where it mates with the connecting ear.

[0042] When the two sides of the floating limit strip abut against the corresponding side of the positioning groove, the width of the floating limit strip can be appropriately narrowed when extending along the curve. This makes it easier to bend outwards to release the connecting ear during interventional heart valve release, thus avoiding delays in the dislodgement of the connecting ear.

[0043] Optionally, the floating limiting strip extends at the part where it mates with the connecting ear, with equal or unequal width.

[0044] Optionally, the floating limiting strip extends with equal or unequal thickness at the portion where it mates with the connecting ear. Whether the portion of the floating limiting strip mates with the connecting ear extends along a straight line or a curve, it can be set to have unequal width and / or unequal thickness. The local strength can be adjusted by varying the width and thickness, thus balancing limiting and releasing the connecting ear.

[0045] Preferably, the end of the floating limit bar has a smooth outer peripheral surface.

[0046] During use, the floating limiting strip expands radially as the valve stent is released. To prevent the expanded end from piercing the inner wall of the blood vessel, the end has a smooth outer contour, such as a spherical crown or rounded edges.

[0047] Preferably, 2, 3 or 4 floating limit bars are evenly arranged circumferentially.

[0048] Preferably, the floating limit bars are of equal or unequal length.

[0049] When the lengths are unequal, the positions of the ends of the floating limit strips can be different. For example, at least one floating limit strip may extend to be flush with the distal end of the fixation head; or at least one floating limit strip may extend to the distal end of the interventional heart valve installation position.

[0050] Preferably, the floating limiting strip consists of three equal-length strips, all of which are long strips.

[0051] Preferably, the floating limit bar has a hollow or solid structure.

[0052] Preferably, the floating limit bar is a solid flat strip.

[0053] The flat strip structure occupies less radial space at the interventional heart valve installation site, which helps to reduce the outer diameter after compression.

[0054] Preferably, the dimensions of the floating limit strip are: length 10mm-80mm, width 1-2mm, and thickness 0.2-0.5mm.

[0055] Preferably, the floating limit strip is fixed to the connected component by means of adhesive, binding, locking, welding or integration.

[0056] The floating limiting strip has a starting end at one end and an ending end at the other, with an extension section in the middle. The starting end is located at the tail end near the fixed head or at the connection point between the tail end and the inner sheath tube, and is fixed to the connected component by adhesive, binding, locking, welding, or integrated methods. The floating limiting strip extends from the starting end to the distal end. In its natural state, the starting end of the floating limiting strip is fixed, while the extension section and the ending end extend and open along the axial direction of the core tube assembly.

[0057] Optionally, after interventional heart valve loading, the distal end of the floating limiting strip is axially at least partially overlapped on the connecting lug.

[0058] Optionally, the far end of the floating limit bar is axially stacked with the connecting ear and the fixing head.

[0059] Optionally, the far end of the floating limit bar is axially stacked on top of the connecting ear and the entire fixed head.

[0060] Optionally, the distal end of the floating limiting strip extends beyond the distal end of the fixed head to the maximum diameter portion of the interventional heart valve.

[0061] Preferably, at least one of the locations where the floating limiting strip engages with the outer sheath and with the bracket has a smooth surface and / or a lubricating coating.

[0062] Preferably, the floating limit strip is made of polytetrafluoroethylene.

[0063] Preferably, a fixed guide bar is also provided on the inner wall of the outer sheath and extends axially.

[0064] One side of the fixed guide bar is fixed inside the tubular shell at the distal end of the outer sheath (along the direction away from the operator from the delivery device), and the fixed guide bar extends axially along the tubular shell. During the retraction and release of the valvular stent from the outer sheath, the valvular stent is in direct contact with the fixed guide bar located inside the tubular shell of the outer sheath, and the valvular stent is rapidly and precisely controlled via the smooth track provided by the fixed guide bar.

[0065] The fixed guide strip can be partially or completely fixedly connected to the inner wall of the outer sheath, or multiple fixed points can be spaced out. Since the fixed guide strip needs to reciprocate with the outer sheath, it is preferable that the two ends of the fixed guide strip are at least fixed to the inner wall of the outer sheath to avoid tilting and causing spatial interference during movement.

[0066] Before surgery, the external sheath is used to retract the valve stent, and the fixation guide strip is placed in close contact with the valve stent. During the subsequent valve stent release, the fixation guide strip provides a smooth track between the tubular shell of the external sheath and the valve stent (on the side closer to the valve stent), reducing contact friction and facilitating the release and control of the valve stent.

[0067] In this invention, the terms "floating" guide bar and "fixed" guide bar are relative. "Floating" means that one end is fixed while the other end can swing at least radially without external restraint. Due to the limitations of its own material strength, circumferential displacement is also generally allowed.

[0068] Preferably, the floating limit bar and the fixed guide bar are arranged alternately along the circumference.

[0069] The distribution of each fixed guide bar and the staggered arrangement of the positioning groove on the fixed head also means that they are staggered with the floating limit bar and the fixed guide bar.

[0070] Preferably, the end of the floating limiting strip is arranged at the same axial position as or staggered with the far end of the fixed guide strip.

[0071] Preferably, 2, 3 or 4 fixed guide strips are evenly arranged circumferentially.

[0072] Preferably, the fixed guide bars are of equal or unequal length.

[0073] Preferably, the fixed guide strip consists of three strips of equal length, all of which are elongated strips.

[0074] Preferably, the fixed guide bar is a hollow or solid structure.

[0075] Preferably, the fixed guide strip is a solid, flat strip.

[0076] The flat strip structure occupies less radial space at the interventional heart valve installation site, which helps to reduce the outer diameter after compression.

[0077] Preferably, the dimensions of the fixed guide strip are: length 10mm-80mm, width 1-2mm, and thickness 0.2-0.5mm.

[0078] Preferably, the length of the fixed guide strip is 60mm-80mm.

[0079] In this invention, the shape and size of the floating limiting strip and the fixed guide strip are set independently. For example, they can be solid or hollow structures of long strips. Their cross-sectional shape is preferably flat. In order to reduce the overall radial dimension of the distal end of the outer sheath, the thickness direction of the flat shape is the radial direction of the outer sheath.

[0080] To facilitate the release and retrieval of the support and reduce the contact area with the outer sheath, thereby reducing the relative friction between the two, the floating limit strip and the fixed guide strip are also selected with appropriate sizes.

[0081] Preferably, the fixing guide strip is fixed to the inner wall of the outer sheath tube by means of adhesive, binding, locking, welding or integration.

[0082] Preferably, the portion of the fixed guide strip that mates with the interventional heart valve has a smooth surface and / or a lubricating coating.

[0083] Preferably, the fixed guide strip is made of polytetrafluoroethylene.

[0084] In this invention, the materials of the floating limiting strip and the fixed guide strip can be selected independently. Preferably, they are made of biocompatible materials with good elasticity. The specific materials can be selected using existing technologies.

[0085] To ensure that the floating limiting strip and the fixed guide strip have suitable elasticity and a minimum coefficient of dynamic friction, the slide rail material is preferably polytetrafluoroethylene (PTFE). After the valve stent is released into the body, the slide rail retracts with the delivery system. During the retraction process, the slide rail comes into contact with and rubs against the fully released valve stent. To prevent the elastic force between the slide rail and the valve stent from moving the stent during the retraction process, more preferably, the outer surface of the floating limiting strip or the fixed guide strip is as smooth as possible or a lubricating coating is provided on the surface. The lubricating coating material can be a hydrophilic monomer or polymer with lubricating properties, such as N,N-dimethylacrylamide (DMAA), acrylamide (AAm), N-vinylpyrrolidone (NVP), polyvinyl alcohol (PVA), polyacrylamide (PAAm), polyethylene glycol (PEG), etc. The above coating material is attached to the outer surface of the floating limiting strip or the fixed guide strip by coupling agent or chemical method.

[0086] In the outer sheath, the inner layer, the middle layer, and the outer layer are arranged sequentially from the inside to the outside along the radial direction of the outer sheath, and the first segment, the second segment, and the third segment are distributed sequentially from the distal end to the proximal end of the outer sheath.

[0087] Because the perforated units on the first segment are circumferentially separated at the distal end of the first segment, the first segment can expand to conform to the inner and outer layers. This allows the distal end of the outer sheath to have better expandability while providing sufficient axial and radial support. Furthermore, the perforated units are in a retracted state, further providing sufficient axial and radial support. Therefore, during the interventional heart valve retrieval process, sufficient axial and radial support is provided to ensure the rapid and safe retrieval of the interventional heart valve.

[0088] In one embodiment, two adjacent cutout units are provided with a cutout gap between the far ends of the first circumferential segment, and the cutout gap L is in the range of 0.5mm-8mm.

[0089] In one embodiment, an axially open space is formed between two adjacent hollow units.

[0090] In one embodiment, the hollowed-out units in the first circumferential direction form multiple hollowed-out unit groups, and adjacent hollowed-out unit groups are separated from each other in the first circumferential direction.

[0091] In one embodiment, two adjacent cutout units are separated from each other at the far end of the first segment in the circumferential direction, connected to each other or independent of each other at the near end of the first segment in the circumferential direction, and connected to the second segment.

[0092] In one embodiment, the hollow unit has at least one hollow hole that extends from the distal end to the proximal end along the axial direction of the hollow unit.

[0093] In one embodiment, the hollow unit includes at least one hollow segment, and the hollow segment has at least one hollow hole.

[0094] In one embodiment, the area of ​​the perforated hole accounts for 40-80% of the area of ​​the perforated unit.

[0095] In one embodiment, the area of ​​the perforated hole accounts for 60-70% of the area of ​​the perforated unit.

[0096] In one embodiment, the far end of the hollow unit is provided with an arc segment, and the arc segment protrudes from the far end of the hollow unit in the arc direction.

[0097] In one embodiment, the radius of the arc segment ranges from 0.3 mm to 16 mm.

[0098] The present invention also provides an outer sheath, including a delivery conduit, a transition tube, and an outer sheath tube, wherein the delivery conduit, the transition tube, and the outer sheath tube are connected sequentially from the distal end to the proximal end of the outer sheath, and the axis of the delivery conduit, the axis of the transition tube, and the axis of the outer sheath tube are arranged to coincide.

[0099] The present invention also provides an interventional heart valve delivery device for delivering an interventional heart valve, comprising a core tube assembly, an outer sheath, and an operating handle. The core tube assembly is connected to the operating handle, and the outer sheath is slidably sleeved on the core tube assembly. The interventional heart valve is loaded on the core tube assembly and housed within the outer sheath tube of the outer sheath.

[0100] Compared to existing technologies, the outer sheath, the outer sheath containing the outer sheath, and the interventional cardiac valve delivery device are circumferentially separated at the distal end of the first segment due to the hollowed-out unit on the first segment. The first segment can expand to conform to the inner and outer layers, thereby providing better expandability at the distal end of the outer sheath while possessing sufficient axial and radial support. Furthermore, the hollowed-out unit is in a retracted state, further providing sufficient axial and radial support. This ensures sufficient axial and radial support during the interventional cardiac valve retrieval process, enabling quick and safe retrieval of the interventional cardiac valve. The use of a floating limiting strip reduces the contact area between the outer sheath and the interventional cardiac valve to a certain extent, and also acts as a smooth track, reducing the relative friction when they come into contact. During the forward and backward movement of the outer sheath, the contact with the floating limiting strip reduces the direct force exerted by the surgeon, thereby achieving precise control over the release and retrieval of the valve stent. Furthermore, a fixed guide strip can be combined; before surgery, the outer sheath retracts the valve stent, and the fixed guide strip is in close contact with the valve stent. During subsequent valve stent deployment, the fixation guide bar provides a smooth track between the outer sheath tubular shell and the valve stent, reducing contact friction and facilitating the deployment and control of the valve stent. Attached Figure Description

[0101] Figure 1 This is a schematic diagram of the conveying device of the present invention;

[0102] Figure 2 This is a schematic diagram of the structure of the distal part of the conveying device of the present invention;

[0103] Figure 3 This is a structural diagram of the locking mechanism;

[0104] Figure 4 This is a schematic diagram of the structure at the end of the floating limit bar;

[0105] Figure 5a Diagram showing the partial release state of the interventional heart valve;

[0106] Figure 5b A diagram showing the partial release of the interventional floating limit strip during the release process of the heart valve;

[0107] Figure 5c This is a diagram showing the state of the interventional heart valve during complete deployment.

[0108] Figure 6 This is a structural diagram showing the use of a limiting strip;

[0109] Figure 7a This is a schematic diagram of the structure of another interventional device before its release;

[0110] Figure 7b for Figure 7aSchematic diagram of the structure of the interventional device before release (relative) Figure 7a (Part of the outer sheath was removed);

[0111] Figure 8 This is a structural diagram showing the assembly with the fixed guide strip;

[0112] Figure 9 This is a schematic diagram of the cross-section of the outer sheath.

[0113] Figure 10a A diagram showing the state of an interventional device before full release when equipped with a floating limit bar and a fixed guide bar;

[0114] Figure 10b Diagram showing the state of an interventional device before full release when equipped with a floating limit bar and a fixed guide bar (relative). Figure 10a (Part of the outer sheath was removed);

[0115] Figure 11a This is a schematic diagram of the part where the connecting ear and the fixing head mate.

[0116] Figure 11b for Figure 11a A schematic diagram showing the connecting ear being pressed against the floating limit bar;

[0117] Figure 12a This is a schematic diagram of another type of connection between the connecting ear and the fixing head;

[0118] Figures 12b-12d for Figure 12a A schematic diagram showing the connecting ear being pressed against floating limit bars of different shapes;

[0119] Figures 13a-13d This is a schematic diagram of another type of connecting ear being pressed against floating limit bars of different lengths;

[0120] Figure 14 This is a schematic diagram of the structure of the conveying device provided by the present invention;

[0121] Figure 15 This is a schematic diagram of the structure of the distal part of the conveying device provided by the present invention;

[0122] Figure 16 This is a schematic diagram of the structure of the outer sheath provided by the present invention;

[0123] Figure 17 A schematic cross-sectional view of the delivery conduit provided by the present invention;

[0124] Figure 18 This is a schematic diagram of the interventional cardiac valve structure provided by the present invention;

[0125] Figure 19 A schematic cross-sectional view of the outer sheath tube provided by the present invention;

[0126] Figure 20 A schematic diagram of the structure of the second intermediate layer provided by the present invention;

[0127] Figure 21 This is a structural schematic diagram of the second intermediate layer provided by the present invention from another perspective;

[0128] Figure 22 A schematic diagram of the flared state structure of the second intermediate layer provided by the present invention;

[0129] Figure 23 This is a schematic diagram of the distal structure of the second intermediate layer provided by the present invention;

[0130] Figure 24 Provided by the present invention Figure 21 Enlarged view of the structure at point E in the middle;

[0131] Figure 25 Provided by the present invention Figure 24 Enlarged view of the structure at point F;

[0132] Figure 26 This provides a schematic diagram of another embodiment of the second intermediate layer at the far end of the present invention. Detailed Implementation

[0133] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. The proximal end, as used herein, refers to the end along the delivery device closer to the operator, and the distal end refers to the end along the delivery device farther from the operator. In the embodiments, interventional cardiac valves are exemplified by valve stents.

[0134] See Figure 1 The conveying device of the present invention includes a guide head 2, a core tube assembly 7, a floating limit bar 1, a fixed head 3, an inner sheath tube 4, an outer sheath tube 5, and an operating handle 6.

[0135] Both the guide head 2 and the fixing head 3 are fixed on the core tube assembly 7. The guide head 2 is located at the farthest end of the core tube assembly 7, and the fixing head 3 is also sleeved on the far side of the core tube assembly 7. The space between the guide head 2 and the fixing head 3 is the interventional heart valve installation position. The outer sheath 5 is located outside the interventional heart valve installation position and can slide axially. The proximal ends of the core tube assembly 7 and the outer sheath 5 are connected to the operating handle 6. The axial sliding of the outer sheath 5 relative to the core tube assembly 7 can be achieved through the operating handle 6. In addition, the inner sheath 4 is provided as needed or can be omitted. The inner sheath 4 is sleeved on the core tube assembly 7 and located on the proximal side of the fixing head 3. The inner sheath 4 generally does not move axially with the outer sheath 5. When the core tube assembly is made of stainless steel, the inner sheath can also be considered as a coating layer on the outer surface of the core tube assembly 7.

[0136] The core tube assembly 7 can be a single component or it can be composed of two segments that are plugged together and fixed. The plugging part is preferably located inside the fixing head 3 to ensure connection strength and smooth surface.

[0137] Figure 1 The floating limit bar 1 consists of three bars of equal length, arranged sequentially in the circumferential direction, and naturally extends in a released state when not restrained by the outer sheath tube 5.

[0138] See Figure 2 The floating limiting strip 1 can be divided into a starting end 103, an extension 102, and a terminal end 101 according to its location. The starting end 103 is fixed to the core tube assembly 7 and is located on the proximal side of the fixed head and tail 32, as shown in the figure, between the inner sheath 4 and the fixed head and tail 32. Of course, the starting end 103 can also be set on the core tube assembly 7, for example, on the core tube assembly 7 between the proximal side of the fixed head and tail 32 and the distal side of the inner sheath 4. The outer periphery of the fixed head 3 is provided with a positioning groove. Since the positioning groove needs to cooperate with the connecting ear of the interventional heart valve, its position and shape can be matched with the connecting ear. There are three positioning grooves in the figure, and their axial positions are staggered, such as positioning groove 31 and positioning groove 33 in the figure. In order not to block the extension of the floating limiting strip 1, the positioning groove adopts an axially through structure. When the valve stent is released, the connecting ear expands radially outward and disengages from the positioning groove. Therefore, the radially outer side of the positioning groove is open, that is, it has a radial opening.

[0139] The positioning groove in the figure is axially continuous and has extended wings on both sides to fit the T-shaped connecting lugs. When the floating limit bar 1 extends to the far end, it passes through the axially continuous part of the corresponding positioning groove. Figure 2 The floating limit bar 1 is in the loading state.

[0140] The starting end 103 of the floating limit strip can be fixed by adhesive, binding, locking, welding, or integrated methods. The adhesive material is a biocompatible, corrosion-resistant crosslinking agent. The binding material is a flexible, corrosion-resistant binding thread.

[0141] Welding can be achieved by connecting a locking clip made of alloy material to the fixed head and tail or core tube assembly, and then tightening the starting end with the locking clip, for example, see [link to example]. Figure 3 The starting end 103 of the floating limit bar 1 is clamped in the stainless steel (material 306) buckle 14. Only part of the extension 102 is shown in the figure. The buckle 14 is connected to the fixing head 3 or the core tube assembly 7 by welding.

[0142] The floating limit bar 1 is a long, solid or hollow structure. In this embodiment, a solid flat bar is used, and the end 101 can be made of an arc-shaped outer edge to avoid sharp corners (see...). Figure 4 ).

[0143] Each floating limit bar 1 is 10mm-80mm long, 1-2mm wide, and 0.2-0.5mm thick. When the floating limit bar 1 has its maximum length, the entire floating limit bar 1 can be guaranteed to be retracted within the outer sheath tube 5.

[0144] Combination Figure 5a and Figure 5b To ensure that the floating limit strip 1 has a small coefficient of dynamic friction, the floating limit strip 1 is made of polytetrafluoroethylene. Each floating limit strip 1 in the figure is 15mm long, the width is adapted to the width of the positioning groove of the fixed head 3, and the thickness is 0.5mm. When the floating limit strip 1 is in the contracted state, the three floating limit strips 1 pass through the corresponding positioning groove along the axial direction and extend further to the distal end. The valve stent 8 has three T-shaped connecting ears 81. In order to adapt to the shape of the connecting ears, the positioning groove is axially connected on the basis of the T-shape, that is, it is cross-shaped. In order to ensure the limiting effect, the axially connected area of ​​the positioning groove is completely closed by the corresponding floating limit strip 1. That is, the width of the floating limit strip 1 is adapted to the width of the axially connected area. If the connected area does not extend with equal width along the axis, then the width of the floating limit strip 1 is at least corresponding to the narrowest part of the connected area to ensure that it is partially or completely submerged in the positioning groove. The outer side of the floating limit strip 1 can be slightly higher than the outer peripheral surface of the fixed head 3 to reduce the friction between the outer peripheral surface of the fixed head 3 and the inner wall of the outer sheath 5.

[0145] When the valve stent 8 is loaded onto the delivery device, the floating limiting strip 1 wraps around the valve stent 8 and is contained within the outer sheath 5; during the release of the valve stent 8, as... Figure 5a As shown, along the direction of arrow M, the outer sheath 5 smoothly retracts along the floating limiting strip 1 (the floating limiting strip is inside the outer sheath 5 in the figure and is therefore not shown). At this time, the floating limiting strip 1 is in the working state: when the bracket connecting ear 81 is inside the outer sheath 5, due to the restraint of the outer sheath 5, the floating limiting strip 1 acts on the bracket connecting ear 81 to prevent the bracket connecting ear 81 from popping out. Then, as... Figure 5bAs shown, as the outer sheath 5 is further retracted along arrow M, the end 101 of the floating limiting strip 1 is released from the restraint of the outer sheath 5. The extension section 102 and the stent connecting ear remain inside the outer sheath 5. At this time, the extension section 102 acts on the stent connecting ear 81, giving the valve stent connecting ear 81 a radial pressure, so that the valve stent connecting ear is firmly grasped, overcoming the huge expansion force generated by the stent during self-expansion release, and firmly locking it in the positioning groove 33 of the stent fixing head 3, avoiding the risk of it being completely released due to detachment from the positioning part of the fixing head. If the valve release position is found to be inaccurate at this time, the valve stent 8 can be pulled back into the outer sheath 5 by advancing the outer sheath 5, for retrieval and secondary release. Compared with the prior art, the present invention can quickly achieve retrieval and positioning. On the one hand, the outer sheath 5 (the structure of the outer sheath 5 is described below) has enhanced axial support force, which can expand radially to promote the radial contraction of the valve stent. On the other hand, since the floating limit strip 1 acts as a gasket, it can greatly reduce the resistance when the outer sheath slides forward, so that the outer sheath 5 can move forward quickly to compress the valve stent.

[0146] Finally, when the current release location is determined to be accurate, such as Figure 5c As shown, continue to retract the outer sheath 5 along arrow M. The end 101 and extension 102 of the floating limiting strip 1 are no longer bound by the outer sheath 5. The end 101 and extension 102 of the floating limiting strip 1 unfold with the unfolding of the valve stent 8. At this time, the floating limiting strip 1 is in a non-working state, that is, no force is applied to the connecting ear 81, thereby completing the release of the valve stent 8. When fully released, the radial pressure of the floating limiting strip on the connecting ear disappears synchronously with the retraction of the outer sheath 5, and will not cause new interference to the valve stent that has been properly released, which can effectively prevent the valve stent from shifting.

[0147] The force exerted by the floating limiting strip 1 on the stent connecting ear comes from two sources: firstly, the constraint of the outer sheath; and secondly, the starting end 103 of the floating limiting strip 1 is fixed close to the fixing head 3, and the extension 102 adjacent to the starting end 101 is also constrained by the starting end 103. When the connecting ear of the valve stent 8 is embedded in the positioning groove 33 of the fixing head 3, the proximal extension of the floating limiting strip 1 adheres tightly to the positioning groove 33, applying a radially inward pressure to the connecting ear of the valve stent 8. This prevents the connecting ear of the valve stent 8 from prematurely disengaging from the positioning groove 33 of the fixing head 3 during release, thus preventing the valve stent 8 from being suddenly released. Furthermore, if positioning deviations or other issues are found during the release of the valve stent 8, requiring repositioning, the constraint force exerted by the proximal end of the floating limiting strip 1 on the connecting ear within the positioning groove 33 ensures that the outer sheath 5 is pushed forward along the floating limiting strip 1, converging the released portion of the valve stent 8, thereby achieving the retrieval of the valve stent 8.

[0148] See Figure 6In other embodiments, the floating limit bar 1 has a shorter axial length and its end is flush with the far end of the fixed head 3.

[0149] The floating limiting strip 1 provides a smooth track between the connecting ear of the valve stent 8 and the outer sheath 5, and between the outer sheath 5 and the fixing head 3, reducing the relative friction when they come into contact. During the forward and backward movement of the outer sheath 5, the direct force exerted by the doctor during operation can be reduced by contact with the floating limiting strip 1, thereby achieving precise control over the release and retrieval of the valve stent 8.

[0150] Figure 6 The floating limit strip 1 consists of three solid strips made of polytetrafluoroethylene. The starting end of the floating limit strip 1 is fixed to the near end of the fixed head 3 by adhesive bonding. The end of the floating limit strip 1 is flush with the far end of the fixed head 3, which means that it can at least completely cover and confine the connecting ear part within the positioning groove. The width of the floating limit strip 1 is consistent with the width of the axial through area of ​​the positioning groove 33, and the thickness is 0.5mm.

[0151] Combination Figure 7a 7b Figure 7a This shows a schematic diagram of the structure before the valve stent is fully deployed. Figure 7b In order to clearly show the structure between the connecting ear 81 of the valve stent 8 and the floating limiting strip 1, in Figure 7b The portion of the outer sheath 5 located outside the floating limiting strip 1 and the fixing head 3 is omitted. In this embodiment, the valve stent 8 has a connecting ear 81. When the valve stent 8 is loaded onto the delivery device, the length of the extended floating limiting strip 1 is approximately equal to the distal end of the fixing head 3, and its end can only press against the connecting ear embedded in the positioning groove 33 of the fixing head. When the valve stent 8 is delivered to the human body and released, the outer sheath 5 retracts, and the valve stent 8 is gradually released. At this time, the connecting ear 81 of the valve stent 8 is embedded in the positioning groove 33 of the fixing head. The connecting ear is firmly bound in the positioning groove 33 by the constricting force of the starting end of the floating limiting strip 1, preventing the released valve stent 8 from exerting an outward expansion force on the connecting ear end, which would cause the stent to be released prematurely.

[0152] Using a shorter floating limit strip 1 can avoid affecting the normal release of the stent and causing unnecessary restraint. The length of the floating limit strip 1 can also extend to the middle region of the valve stent 8 axially, for example, not exceeding the maximum axial dimension of the valve when the valve is fully released. Figure 5c Point A in the middle.

[0153] See Figure 8 and Figure 9 In other embodiments, the distal inner wall of the outer sheath 5 is also provided with a fixing guide strip 51.

[0154] In addition to the floating limit bar 1, guide head 2, fixing head 3, inner sheath 4, outer sheath 5, and valve stent 8 shown in the figure, a fixing guide bar 51 is also provided on the inner wall of the outer sheath 5. The fixing guide bar 51 consists of three bars of equal length, evenly arranged in the circumferential direction, and fixed to the inner surface of the tubular shell at the distal end of the outer sheath 5, providing a smooth track between the valve stent 8 and the outer sheath 5.

[0155] The circumferential positions of each fixed guide bar 51 are staggered with the positioning grooves on the fixed head 3 (i.e., the circumferential distribution of the floating limit bars 1). When the outer sheath tube 5 retracts the valve stent 8, the proximal end of the fixed guide bar is close to the fixed head 3, and its position is staggered with the positioning grooves.

[0156] The fixed guide strip 51 is a solid flat strip with a length of 10mm-80mm, a width of 1-2mm, and a thickness of 0.2-0.5mm. In this embodiment, the length of the fixed guide strip 51 corresponds to the axial length of the valve stent 8, which is about 60mm.

[0157] The fixing guide strip 51 is fixed to the inner wall of the outer sheath 5 by means of adhesive bonding, binding, locking, welding, or integration. The fixing guide strip 51 is made of polytetrafluoroethylene (PTFE), and the part that mates with the interventional cardiac valve 8 has a smooth surface and / or a lubricating coating. In the optimal implementation, the fixing guide strip 51 is integrally formed with the inner wall of the outer sheath 5, and the fixing guide strip 51 is a protruding ridge protruding into the outer sheath 5, having a smooth surface and / or a lubricating coating.

[0158] Combination Figure 10a , 10b , Figure 10a The diagram shows the release state of the interventional device with the floating limiting strip and the fixed guide strip assembled. To clearly show the structure between the connecting lug 81 of the valve stent 8 and the floating limiting strip 1, Figure 10b The portion of the outer sheath 5 located outside the floating limit bar 1 and the fixing head 3 is omitted. When the valve stent 8 is released, the outer sheath 5 slides in contact with the valve stent 8 through the fixing guide bar 51, and the outer sheath 5 can be retracted under very low friction to achieve the gradual release of the stent.

[0159] When the outer sheath 5 is retracted to the position of the fixed head 3, only the connecting ear of the valve stent 8 is contained within the outer sheath 5. At this point, the fixed guide strip 51 is completely disengaged from the valve stent 8, and the floating limiting strip 1 is pressed tightly against the connecting ear by the constriction of the outer sheath 5. As the outer sheath 5 continues to be retracted, the constriction force of the floating limiting strip 1 on the connecting ear gradually decreases, and the connecting ear is gradually released. In summary, the valve stent 8 achieves gradual release through the smooth track provided by the fixed guide strip 51 and the floating limiting strip 1, and the radially inward tightening force.

[0160] As a further improvement of the present invention, in other embodiments, a portion of the floating limiting strip is disposed on / inside the positioning groove of the fixed head, serving to limit the radial outward expansion of the bracket fixing ear from disengaging from the positioning groove; the other portion is disposed on the outer peripheral wall of the fixed head, acting as a slide rail, along which the outer sheath slides. In the optimal manner, the farthest end of the floating limiting strip corresponding to the positioning groove is aligned with or does not exceed the farthest end of the fixed head, or slightly exceeds the farthest end of the fixed head.

[0161] The following embodiments mainly focus on the length and shape of the floating limit bar, as well as the way the connecting ear and the fixing head cooperate. Other components can be adopted or combined with at least one of the aforementioned embodiments.

[0162] See Figure 11a and Figure 11b The connecting ear 81 is T-shaped, and the positioning part on the fixing head 3 is a positioning groove 33. After the valve is loaded, the connecting ear 81 is embedded in the corresponding positioning groove 33. The floating limiting strip 1 is bound and pressed on the connecting ear 81 by the outer sheath tube to prevent the connecting ear 81 from falling out of the positioning groove 33. During the release of the stent, the limiting of the connecting ear 81 is released only when the outer sheath tube is completely separated from the floating limiting strip 1.

[0163] See Figures 12a-12d The connecting ear 81 is U-shaped, with one side of the U-shaped opening connected to the bracket and the U-shaped opening closed. The positioning part on the fixing head 3 is the positioning protrusion 34. The connecting ear 81 is hung on the positioning protrusion 34 using the U-shaped structure, which can achieve axial positioning. In order to prevent the connecting ear 81 from protruding too much radially, a settling groove 35 is provided on the outer periphery of the positioning protrusion 34, that is, the outer wall of the fixing head 3. The connecting ear 81 is stacked in the settling groove 35, and can achieve the same height as the outer wall of the fixing head 3 in the radial direction.

[0164] Figure 12b In the middle, the floating limit bar 1 has a bifurcated structure, that is, a U-shape. The unbifurcated part is fixed to the outside of the fixed head 3, and the bifurcated part extends to the far end until it overlaps the outside of the connecting ear 81.

[0165] Figure 12c In the middle, the floating limit bar 1 is a single strip structure, which also extends to the far end until it overlaps the outside of the connecting ear 81.

[0166] Figure 12d In the middle, the floating limit bar 1 is a forked mechanism, but it adopts a V-shape or Y-shape. The unforked part is fixed to the outside of the fixed head 3, and the forked part extends to the far end until it overlaps the outside of the connecting ear 81.

[0167] See Figures 13a-13dThe diagram shows a structural schematic of the connecting ear being compressed by floating limiting strips 1 of different lengths. When the heart valve is being loaded, the outer sheath 5 binds the floating limiting strip 1, positioning the connecting ear 81 outside the fixing head. Taking the positioning protrusion 34 on the fixing head as an example, the distal side of the floating limiting strip 1 at least partially overlaps the connecting ear 81.

[0168] Figure 13a It can be seen that the far end of the floating limit strip 1 overlaps the connecting ear 81. The far end of the floating limit strip 1 has not yet extended to the positioning protrusion 34, but only overlaps a small part of the connecting ear 81.

[0169] Figure 13b It can be seen that the far end of the floating limit bar 1 overlaps the connecting ear 81. The far end of the floating limit bar 1 completely covers the positioning part on the fixed head in the axial direction, that is, it passes over the positioning protrusion 34 and reaches the far end of the fixed head 3. The connecting ear 81 and the entire fixed head 3 overlap in the axial direction towards the far end.

[0170] Figure 13c It can be seen that the distal end of the floating limit strip 1 overlaps the connecting lug 81, and the distal end of the floating limit strip 1 extends axially over the fixed head.

[0171] Figure 13d It can be seen that the distal end of the floating limiting strip 1 overlaps on the connecting ear 81. The distal end of the floating limiting strip 1 passes over the fixing head in the axial direction and reaches the part with the largest diameter of the interventional heart valve. After the valve is loaded, due to the constraint of the outer sheath, the outer diameter of the interventional heart valve is basically the same. Therefore, the part with the largest diameter can be understood as the part with the largest diameter in the released state.

[0172] The following embodiments mainly describe improvements to the outer sheath tube. The floating limit bar or other components may be adopted or combined with at least one of the aforementioned embodiments.

[0173] See Figure 14 as well as Figure 18 The delivery device 100 is used to deliver the interventional heart valve 82 to the corresponding location on the human body. The interventional heart valve 82 can be a valve stent or a stent of the same type.

[0174] The delivery device 100 includes a core tube assembly 10, an outer sheath 20, and an operating handle 30. The core tube assembly 10 is connected to the operating handle 30, and the outer sheath 20 is slidably sleeved on the core tube assembly 10, located between the core tube assembly 10 and the operating handle 30. The interventional heart valve 82 is mounted on the core tube assembly 10 and housed within the outer sheath 20. The operating handle 30 is used to control the axial forward movement or retraction of the core tube assembly 10 relative to the outer sheath 20, thereby releasing or retracting the interventional heart valve 82.

[0175] The core tube assembly 10 includes a core tube 11 and a guide head 12. The proximal end of the core tube 11 is connected to the operating handle 30, and the distal end of the core tube 11 extends through the outer sheath 20 and is connected to the guide head 12. It should be noted that the terms "proximal end" and "distal end" are relative; specifically, the proximal end refers to the end of the conveying device 100 closer to the operator, and the distal end refers to the end of the conveying device 100 farther from the operator.

[0176] See Figure 15 The core tube 11 includes a middle tube 111 and a loading section 112. The proximal end of the middle tube 111 is connected to the operating handle 30, and the distal end of the middle tube 111 is provided with a fixing head 1111 and a floating limiting strip 1112. The fixing head 1111 is used to match and fix the interventional heart valve 82. The loading section 112 is located between the fixing head 1111 and the guide head 12. The proximal end of the loading section 112 is fixed to the fixing head 1111, and the distal end of the loading section 112 is connected to the guide head 12. The loading section 112 is located within the outer sheath 20 and is used to load the interventional heart valve 82.

[0177] Furthermore, the length of the floating limiting strip in the axial direction of the core tube 11 is greater than the length of the fixed head 1111 in the axial direction of the core tube 11.

[0178] The floating limiting strip 1112 can be fixed to the central tube 111 by means of adhesive bonding, binding, locking, welding, or integration. The floating limiting strip 1112 reduces the contact area between the outer sheath 20 and the interventional heart valve 82 to a certain extent. It also acts as a smooth track to reduce the relative friction when the outer sheath 20 and the interventional heart valve 82 are in contact. During the axial forward or backward movement of the core tube 11 relative to the outer sheath 20, the direct force exerted by the doctor during operation can be reduced through contact with the floating limiting strip 1112, thereby achieving precise control over the release and retraction of the interventional heart valve 82.

[0179] See Figure 16The outer sheath 20 is typically formed as a tubular structure, possessing a certain degree of flexibility, axial support, and radial support. It includes a delivery conduit 21, a transition tube 22, and an outer sheath 23. The proximal end of the delivery conduit 21 is connected to the operating handle 30, and the distal end of the delivery conduit 21 is connected to the outer sheath 23. The interior of the delivery conduit 21 communicates with the interior of the outer sheath 23. The transition tube 22 connects the delivery conduit 21 and the outer sheath 23. The core tube 11 passes sequentially through the delivery conduit 21, the transition tube 22, and the outer sheath 23.

[0180] The strength of the distal end of the delivery catheter 21 increases sequentially from the delivery catheter 21 to the outer sheath 23. This gives the delivery catheter 21 a certain degree of flexibility while also providing axial support, allowing it to accommodate different implantation sites. The diameter of the delivery catheter 21 is smaller than the diameter of the outer sheath 23.

[0181] See Figure 17The delivery conduit 21 comprises a three-layer structure. Specifically, the delivery conduit 21 includes a first inner layer 211, a first intermediate layer 212, and a first outer layer 213 arranged sequentially from the inside to the outside along the radial direction of the delivery conduit 21. The first inner layer 211, the first outer layer 213, and the first intermediate layer 212 can be connected in various ways. For example, the first inner layer 211, the first outer layer 213, and the first intermediate layer 212 can be connected by thermal melting or adhesive; or the first inner layer 211 and the first outer layer 213 can be connected to the first intermediate layer 212 by liquid immersion or spray coating. The first inner layer 211 and the first outer layer 213 can be made of the same or different polymeric lubricating elastomers to give the delivery conduit 21 a certain degree of flexibility, sufficient axial support, and sliding properties. Therefore, even during the implantation of the interventional heart valve 82, if there are tortuous implantation sites (e.g., when bending along the aortic arch), accurate implantation can still be achieved. The first inner layer 211 can be made of polymer materials such as PTFE (Polytetrafluoroethylene) or PEBAX (Polyeher block amide), while the first outer layer 213 can be made of materials such as PTFE, PU (Polyurethane), Pebax (Arkema nylon elastomer), or PE (polyethylene). In this embodiment, the first inner layer 211 and the first outer layer 213 are lubricating elastomers made of the same polymer material, including PTFE (Polytetrafluoroethylene) or PEBAX (Polyeher block amide).

[0182] The first intermediate layer 212 is made of metal braid or cut from metal tubing, so that the delivery conduit 21 can maintain a certain axial support while having a certain degree of flexibility. Preferably, the first intermediate layer 212 is made of cut from metal tubing.

[0183] The transition tube 22 serves as a transitional connection between the delivery conduit 21 and the outer sheath 23. Further, the transition tube 22 has a trapezoidal cross-section. The structure of the transition tube 22 is the same as that of the outer sheath 23.

[0184] After valve loading, the loading section 112 is housed within the outer sheath 23, which is used to accommodate the interventional device 82. Before releasing the interventional device 82, it is compressed and housed within the outer sheath 23 in an ice-water mixture. Here, it should be explained that... (See also...) Figure 18The interventional device 82 includes a stent 83 and a valve, the valve being manually sewn onto the stent 83. The stent 83 is made of nickel-titanium alloy, and the valve is made of biological materials such as porcine pericardium or bovine pericardium. The nickel-titanium alloy stent has shape memory function, softening in an ice-water mixture, thus easily being compressed and folded within the outer sheath 23, and expanding to restore its unfolded shape upon release into the bloodstream.

[0185] During the release process, by operating the operating handle 30, the outer sheath 23 moves axially relative to the core tube 11, releasing the interventional device 82. If the release position of the interventional device 82 is found to be incorrect, the operating handle 30 is used to move the outer sheath 23 forward relative to the core tube, so that the distal part of the outer sheath 23 gradually wraps around the interventional device 82. Under the binding force (circumferential expansion resistance) of the outer sheath 23, the interventional device 82 is compressed and retracted into the outer sheath 23.

[0186] See Figure 19 The axis of the outer sheath 23 coincides with the axis of the delivery conduit 21 and the axis of the transition tube 22. The outer sheath 23 comprises a three-layer structure. Specifically, the outer sheath 23 includes a second inner layer 23a, a second intermediate layer 23b, and a second outer layer 23c arranged sequentially from the inside to the outside along the radial direction of the outer sheath 23. The second inner layer 23a, the second intermediate layer 23b, and the second outer layer 23c can be joined in various ways. For example, the second inner layer 23a and the second outer layer 23c can be connected to the second intermediate layer 23b by heat fusion or adhesive. The second inner layer 23a and the second outer layer 23c can be made of the same or different polymeric lubricating elastomers to give the outer sheath 23 a certain degree of flexibility, sufficient axial support, and sliding properties. The second inner layer 23a can be made of PTFE (Polytetrafluoroethylene) polymer material, and the second outer layer 23c can be made of PTFE, PU (Polyurethane), Pebax (Arkema nylon elastomer), PE (polyethylene), or other materials. In this embodiment, the second inner layer 23a and the second outer layer 23c are lubricating elastomers made of the same polymer material, including PTFE (Polytetrafluoroethylene).

[0187] See Figure 20 as well as Figure 21The second intermediate layer 23b is a reinforcing layer and can be cut from stainless steel or nickel-titanium alloy tubing. Alternatively, the first section can be made of nickel-titanium alloy tubing, while the remaining sections are made of stainless steel. The second intermediate layer 23b enhances the axial support, radial support, binding force (circumferential expansion resistance), and flexibility of the outer sheath 23. During the retraction of the interventional heart valve 82, it provides sufficient binding force to compress and contain the interventional heart valve 82 within the outer sheath 23. Furthermore, the axial support and flexibility provided by the second intermediate layer 23b allow the outer sheath 23 to have good bending performance, thus accommodating different implantation sites and enabling the implantation of the interventional heart valve 82.

[0188] Specifically, the second intermediate layer 23b includes a first segment 231, a second segment 232, and a third segment 233. The first segment 231, the second segment 232, and the third segment 233 are connected in sequence. The first segment 231 is located near the distal end of the outer sheath tube 23, the third segment 233 is located near the proximal end of the outer sheath tube 23, and the second segment 232 is located between the first segment 231 and the third segment 233.

[0189] See Figures 20-25 The first segment 231 employs a hollow structure to ensure that the distal end of the outer sheath 23 possesses sufficient radial elastic force and axial support force. The hollow structure is converging radially along the outer sheath 23. The hollow portion of the hollow structure may include rhombus, square, or teardrop shapes, etc.

[0190] The first segment 231 includes multiple hollow units 2311. These hollow units 2311 are arranged circumferentially along the first segment 231, with adjacent hollow units 2311 separated from each other at their far ends in the circumferential direction. That is, there is a hollow gap L between adjacent hollow units 2311 in the circumferential direction of the first segment 231, and the hollow gap L ranges from 0.5mm to 8mm. Since the first segment 231 is located between the second inner layer 23a and the second outer layer 23c, the first segment 231 can expand in accordance with the second inner layer 23a and the second outer layer 23c. After expansion, the second intermediate layer 23b of the nickel-titanium alloy tube has a shape memory function, which promotes repositioning, thereby greatly increasing the toughness of the radial support force at the distal end of the outer sheath 23. At the same time, the hollow part of the hollow structure is in a closed state, thereby providing sufficient axial support force and effectively preventing the occurrence of wrinkling at the distal end of the outer sheath 23 when the interventional heart valve 82 is withdrawn. Secondly, the circumferentially separated hollow units 2311 give the distal end of the outer sheath 23 a flared opening that expands circumferentially towards the outer sheath, thereby having a buffering effect when the interventional heart valve 82 is retrieved, making the release and retrieval of the interventional heart valve 82 smoother, while avoiding wrinkling of the interventional heart valve 82.

[0191] In this embodiment, the first segment 231 includes 4-6 hollow units 2311. The hollow units 2311 are arranged separately from each other in the circumference of the first segment 231. The hollow units 2311 are evenly distributed along the circumference of the first segment 231. A space of rhombus, rectangle, etc., is formed between two adjacent hollow units 2311, which is not closed in the axial and circumferential directions.

[0192] See Figure 26 In other embodiments, the circumferentially hollowed-out units 2311 of the first segment 231 can form a group of hollowed-out units 2311 with two adjacent hollowed-out units 2311. The two adjacent groups of hollowed-out units 2311 are separated from each other circumferentially in the first segment 231. Alternatively, three hollowed-out units 2311 arranged sequentially can form a group of hollowed-out units 2311, with the two adjacent groups of hollowed-out units 2311 being separated from each other circumferentially in the first segment 231.

[0193] Two adjacent hollow units 2311 are separated from each other at the far end of the first segment 231 in the circumferential direction. Two adjacent hollow units 2311 can be connected to each other or partially connected at the near end of the first segment 231 in the circumferential direction, while also being connected to the second segment 232.

[0194] In other embodiments, two adjacent hollow units 2311 are independently arranged at the circumferential near end of the first segment 231 and are respectively connected to the second segment 232. That is, it can be understood that in this embodiment, two adjacent hollow units 2311 are independently arranged.

[0195] The hollow unit 2311 has at least one hollow hole 2311b, which extends from the distal end to the proximal end along the axial direction of the hollow unit 2311.

[0196] Furthermore, the hollow unit 2311 may have 2-4 hollow holes 2311b. Two adjacent hollow holes 2311b may be interconnected or not interconnected, that is, two adjacent hollow holes 2311b are spaced apart to enhance the structural strength of the hollow unit 2311, so that the hollow unit 2311 has sufficient axial and radial support force.

[0197] In other embodiments, the hollow unit 2311 has two hollow holes 2311b, which are arranged from the distal end to the proximal end along the axial direction of the hollow unit 2311; or, the two hollow holes 2311b are arranged circumferentially along the hollow unit 2311. In other embodiments, the hollow unit 2311 has three hollow holes 2311b, which can be arranged in a straight line, triangle, or other similar manner. It can be understood that the purpose of setting the hollow holes 2311b and the arrangement of the hollow holes 2311b is to improve the overall structural strength, flexibility, radial and axial support of the outer sheath. Any arrangement that can improve the overall structural strength of the outer sheath can be used in this invention; therefore, the arrangement of the hollow holes 2311b is not limited in this invention.

[0198] The hollow unit 2311 includes at least one hollow segment 2311a. At least one hollow hole 2311b is formed on the hollow segment 2311a. Adjacent hollow units 2311 are separated from each other by their furthest hollow segments 2311a. The hollow gap L extends axially along the hollow segment 2311a to divide the hollow unit 2311.

[0199] Furthermore, the arrangement of the hollow holes 2311b on the hollow segment 2311a can be referred to the arrangement of the hollow holes 2311b on the hollow unit 2311, and will not be described again here.

[0200] The area of ​​the perforated hole 2311b is 40%-80% of the area of ​​the perforated unit 2311. Preferably, the area of ​​the perforated hole 2311b is 60%-70% of the area of ​​the perforated unit 2311. Therefore, during the thermal fusion bonding of the second inner layer 23a, the second intermediate layer 23b, and the second outer layer 23c, the adhesion between the second intermediate layer 23b and the second inner layer 23a and the second outer layer 23c is better, the bonding force between the three layers is greater, and the bonding is improved. Furthermore, this enhances the axial and radial support forces of the outer sheath 23 and gives the outer sheath sufficient flexibility. Secondly, the area of ​​the perforated hole 2311b is large enough to facilitate the exhaust of gas from the perforated hole 2311b during the thermal fusion bonding process, further improving the bonding force between the second inner layer 23a, the second intermediate layer 23b, and the second outer layer 23c, thereby strengthening the overall structural strength of the outer sheath 23.

[0201] The perforated hole 2311b is roughly teardrop-shaped. When the perforated unit 2311 has two perforated holes 2311b, the two holes roughly form an "8" shape.

[0202] See Figure 20 as well as Figure 23 The distal end of the hollow unit 2311 is further provided with an arc segment 2311a1. The arc shape of the arc segment 2311a1 protrudes towards the distal end of the hollow unit 2311. The arc segment 2311a1 and the hollow unit 2311 form the hollow hole 2311b. The arc segment 2311a1 has an inner arc segment and an outer arc segment. The radius of the inner arc segment is in the range of 0.3mm-1mm, preferably in the range of 0.5-0.8mm; the radius of the outer arc segment is in the range of 1mm-16mm, preferably in the range of 0.6-3mm, and more preferably in the range of 0.7-2mm. The design of the distal end of the grid body 2311a with an arc segment 2311a1 not only effectively prevents the distal end of the first segment 231 from puncturing or tearing the interventional heart valve 82 during the retraction process; secondly, the arc segment 2311a1 can provide greater radial support force, making the distal end of the outer sheath 23 have greater radial support force, which is more conducive to compressing the interventional heart valve 82 during the retraction process.

[0203] Of course, in other embodiments, the hollow unit 2311 may not have a hollow hole, and two adjacent hollow units 2311 may be separated from each other at the far end of the first segment 231 in the circumferential direction.

[0204] The second segment 232 is used to enhance the overall structural strength and flexibility provided by the outer sheath 23. The axial and radial support forces of the second segment 232 may be greater than those of the first segment 231, thereby providing greater restraint for loading the interventional heart valve 82.

[0205] The second segment 232 includes a first transition segment 2321, a curved segment 2322, and a second transition segment 2323. The first transition segment 2321, the curved segment 2322, and the second transition segment 2323 are distributed sequentially from the distal end to the proximal end of the second intermediate layer 22. The second segment 232 is connected to the first segment 231 through the first transition segment 2321. The first transition segment 2321 has multiple connecting holes 2321a. The total area of ​​the connecting holes 2321a accounts for 60-70% of the area of ​​the first transition segment 2321, thereby maximizing the bonding area when the second segment 232 is thermally fused with the second inner layer 21a and the second outer layer 23c. This improves the overall structural strength of the outer sheath tube 23 while giving the outer sheath tube 23 both flexibility and sufficient axial and radial support.

[0206] Preferably, the connecting hole 2321a includes a circular connecting hole 2321a, an elliptical connecting hole 2321a, a square connecting hole 2321a, etc. In this embodiment, a plurality of circular connecting holes 2321a are provided on the first transition section 2321. The plurality of circular connecting holes 2321a are evenly distributed around the circumference of the first transition section 2321.

[0207] The curved section 2322 is used to provide increased circumferential support, appropriate axial and radial support to prevent the outer sheath 23 from bending or twisting, and overall flexibility so that the outer sheath 23 can meet different implantation points for releasing the interventional heart valve 82.

[0208] Furthermore, the curved segment 2322 includes helical segments 2322a distributed along the axial direction of the curved segment 2322. The curved segment 2322 is formed by helical cutting. The spacing between adjacent helical segments 2322a is t1, and the total spacing t1 on the curved segment 2322 is t. The t accounts for 30-60% of the total height (length) of the curved segment 2322, preferably 40-50% of the total height (length) of the curved segment 2322. This maximizes the bonding area when the curved segment 2322 is thermally fused with the second inner layer 21a and the second outer layer 23c, thereby giving the outer sheath tube 23 both flexibility and sufficient axial and radial support.

[0209] In other embodiments, the bent segment 2322 can be a C-shaped ring, which is formed by cutting a C-shape. Adjacent C-shaped rings are spaced apart but not disconnected; that is, adjacent C-shaped rings are connected to each other. The C-shaped rings are connected in series by reinforcing ribs 2322a. Furthermore, the adjacent C-shaped rings can be equidistant or not; this is not limited in this embodiment.

[0210] The second transition section 2323 is used to connect the curved section 2322 and the third section 233. The second transition section 2323 has multiple connecting holes 2321a. The multiple connecting holes 2321a maximize the bonding area when the second transition section 2323 is thermally fused with the second inner layer 21a and the second outer layer 23c. This further improves the overall structural strength of the outer sheath 23 while ensuring that the outer sheath 23 possesses both flexibility and sufficient axial and radial support.

[0211] Preferably, in this embodiment, the second transition section 2323 has a plurality of square connecting holes 2321a. The plurality of square connecting holes 2321a are evenly spaced and distributed around the circumference of the second transition section 2323. Of course, it can be understood that the square connecting holes 2321a may also be distributed around the circumference of the second transition section 2323 without spacing.

[0212] The third segment 233 extends into the transition tube 22. The third segment 233 includes multiple floating plates 2331, which are circumferentially spaced in the third segment 233. Each floating plate 2331 has multiple connecting holes 2321a. Here, the circumferentially spaced floating plates 2331 facilitate the retraction of the third segment 233 into the transition tube 22. At the same time, the multiple connecting holes 2321a on the floating plates 2331 maximize the bonding area when the third segment 233 is thermally fused with the second inner layer 21a and the second outer layer 23c, thereby further improving the overall structural strength of the outer sheath tube 23.

[0213] In this invention, the interventional heart valve 82 is compressed during loading by utilizing the property that nickel-titanium alloy softens when cooled, thereby compressing and loading the interventional heart valve 82 within the outer sheath 23 in an ice-water mixture. During the release of the interventional heart valve 82 within the body, it gradually unfolds from the distal end of the outer sheath 23. It is conceivable that the body temperature is much higher than that of the ice-water mixture; during release, the interventional heart valve 82 is essentially heated within the body, resulting in a very large expansion force at the distal end of the outer sheath 23. If the release position of the interventional heart valve 82 is found to be inaccurate, and the interventional heart valve 82 is to be recompressed and retracted into the outer sheath 23, the outer sheath 23 needs to provide sufficiently large axial and radial support forces to compress the interventional heart valve 82.

[0214] In this invention, by providing a second intermediate layer 23b inside the outer sheath 23, the bonding between the second inner layer 23a, the second intermediate layer 23b, and the second outer layer 23c of the outer sheath 23 is improved, thereby enhancing the overall axial and radial support force of the outer sheath 23 and giving the outer sheath a certain degree of flexibility, thus providing sufficiently large axial and radial support force during the retrieval process of the interventional heart valve 82.

[0215] Specifically, the perforated hole 2311b is provided at the distal end of the second intermediate layer 23b, with the perforated units 2311 on the first segment 231 being circumferentially separated from each other at the distal end of the first segment 231. This improves the expandability of the distal end of the outer sheath tube 23 and provides sufficient axial and radial support. Furthermore, since the total area of ​​the perforated holes 2311b on the perforated units 2311 accounts for 40-80% of the area of ​​the perforated units 2311, it can be seen that when the second inner layer 23a, the second intermediate layer 23b, and the second outer layer 23c are thermally fused together, the adhesion between the second intermediate layer 23b and the second inner layer 23a and the second outer layer 23c is better, the bonding force between the three layers is greater, and the bonding is better. This improves the axial and radial support force of the outer sheath tube 23 and gives the outer sheath tube sufficient flexibility.

[0216] The working process of the conveying device is described below.

[0217] The interventional heart valve 82 is first compressed in an ice-water mixture, loaded onto the loading section 112 of the core tube assembly 10, and housed within the outer sheath 20. After the interventional heart valve 82 is delivered to the lesion site, the core tube assembly 10 is moved forward relative to a portion of the outer sheath 20 by the operating handle 30, so that the interventional heart valve 82 expands and unfolds within the outer sheath 20.

[0218] Once the precise placement of the interventional heart valve 82 is ensured, the core tube assembly 10 continues to advance, the interventional heart valve 82 is deployed at the lesion site, and the interventional heart valve 82 is disengaged from the fixation head 1111, thus completing the deployment of the interventional heart valve 82.

[0219] If the release position of the interventional heart valve 82 is found to be incorrect during the release process, the core tube assembly 10 is retracted by operating the handle 30. During the retraction process, the outer sheath 20 provides sufficient axial and radial support force and compresses the interventional heart valve 82 under the guidance of the floating limit bar 1112, so as to house the interventional device 82 in the outer sheath 20, thus completing the retrieval of the interventional heart valve 82.

[0220] This invention describes an embodiment using a heart valve stent as the implant. Those skilled in the art will understand that the delivery device disclosed in this invention can also place other implants, besides heart valve stents, into corresponding locations in the body. Those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Obviously, all such modifications and variations should fall within the protection scope claimed by this invention. Furthermore, although certain specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any special limitation on the invention.

Claims

1. A delivery device for an interventional heart valve, comprising a core tube assembly, a guide head and a fixation head fixed on the core tube assembly, wherein the guide head is fixed at the distal end of the core tube assembly, and the fixation head extends from the proximal end of the core tube assembly, and the space between the guide head and the fixation head is an interventional heart valve installation position; an axially slidable outer sheath is provided around the periphery of the interventional heart valve installation position, characterized in that, It is also equipped with a floating limiting strip, the proximal end of which is the starting end fixed relative to the fixed head or core tube assembly. The floating limiting strip floats between the interventional heart valve installation position and the outer sheath. The floating limiting strip is a long strip structure, and 2, 3 or 4 floating limiting strips are evenly arranged in the circumferential direction. The outer wall of the fixing head is provided with a positioning part for cooperating with the connecting ear of the interventional heart valve; When the interventional heart valve is in the loaded state, the distal end of the floating limiting strip is axially at least partially overlapped on the connecting ear, applying radial pressure to the connecting ear to maintain the fit between the connecting ear and the positioning part. Upon release, as the outer sheath is retracted, the floating limiting strip can swing freely and the radial pressure on the connecting ear is released.

2. The interventional heart valve delivery device as described in claim 1, characterized in that, It also includes an outer sheath, which includes a delivery conduit, a transition tube, and the outer sheath tube, wherein the delivery conduit, the transition tube, and the outer sheath tube are connected sequentially from the distal end to the proximal end of the outer sheath.

3. The interventional heart valve delivery device as described in claim 2, characterized in that, The strength of the distal end of the delivery conduit increases sequentially from the delivery conduit to the outer sheath.

4. The interventional heart valve delivery device as described in claim 2, characterized in that, The delivery conduit comprises a three-layer structure consisting of a first inner layer, a first intermediate layer, and a first outer layer arranged sequentially from the inside to the outside along the radial direction of the delivery conduit.

5. The interventional heart valve delivery device as described in claim 4, characterized in that, The first inner layer and the first outer layer are made of the same or different polymer materials.

6. The interventional heart valve delivery device as described in claim 4, characterized in that, The first intermediate layer is made of metal braid or cut from metal tubes.

7. The interventional heart valve delivery device as described in claim 2, characterized in that, The outer sheath tube comprises a three-layer structure consisting of a second inner layer, a second intermediate layer, and a second outer layer arranged sequentially from the inside to the outside along the radial direction of the outer sheath tube.

8. The interventional heart valve delivery device as described in claim 7, characterized in that, The second intermediate layer is a reinforcing layer, which is cut from stainless steel pipe or nickel-titanium alloy pipe; The second intermediate layer includes a first segment, a second segment, and a third segment; The first segment, the second segment, and the third segment are distributed sequentially from the distal end of the outer sheath to the proximal end of the outer sheath.

9. The interventional heart valve delivery device as described in claim 8, characterized in that, The first segment includes a hollow structure, which is converging along the radial direction of the outer sheath.

10. The interventional heart valve delivery device as described in claim 8, characterized in that, The first segment includes multiple hollow units arranged circumferentially along the first segment, with two adjacent hollow units separated from each other at the far end of the first segment's circumference.

11. The interventional heart valve delivery device as described in claim 8, characterized in that, The second segment includes a first transition segment, a curved segment, and a second transition segment distributed sequentially from the distal end to the proximal end of the second intermediate layer, and the second segment is connected to the first segment through the first transition segment.

12. The interventional heart valve delivery device as described in claim 11, characterized in that, The first transition section has multiple connecting holes, and the total area of ​​the connecting holes accounts for 60-70% of the area of ​​the first transition section.

13. The interventional heart valve delivery device as described in claim 11, characterized in that, The curved section includes a helical segment distributed along the axial direction of the curved section, and the curved section is formed by helical cutting.

14. The interventional heart valve delivery device as described in claim 11, characterized in that, The curved section is a C-shaped ring cut into a C shape, with adjacent C-shaped rings spaced apart and connected to each other.

15. The interventional heart valve delivery device as described in claim 1, characterized in that, The positioning part is a positioning groove. After the interventional heart valve is loaded, the connecting ear is embedded in the corresponding positioning groove. Before the connecting ear is completely released from the outer sheath, the floating limiting strip is superimposed on the connecting ear to maintain the fit between the connecting ear and the positioning part.

16. The interventional heart valve delivery device as described in claim 1, characterized in that, The positioning part is a positioning protrusion. After the interventional heart valve is loaded, the connecting ear is fitted onto the positioning protrusion. Before the connecting ear is completely released from the outer sheath, the floating limiting strip is superimposed on the connecting ear to maintain the fit between the connecting ear and the positioning part.

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