Peripheral adaptive guide protection structure for prosthetic heart valve stent implantation

Abstract

This invention relates to the field of medical device technology, and mainly provides a peripheral adaptive guiding protection structure for implantation of artificial heart valve stents. It includes a core tube, an inner sheath, an outer sheath, a capsule assembly body, an external adaptive folding structure, and a self-expanding valve stent. The capsule assembly body includes a capsule cavity movably inserted through the core tube, the capsule cavity having a release opening, a self-expanding valve stent folded within the capsule cavity, an external adaptive folding structure fixedly disposed on the outer wall of the capsule cavity, an outer sheath movably sleeved on the core tube, and an inner sheath movably inserted within the outer sheath. The external adaptive folding structure is configured to have a retracted state folded and attached between the capsule cavity and the outer sheath, and an unfolded state that expands radially outward along the capsule cavity and forms a ring surrounding the capsule cavity and the outside of the release opening. This invention solves the technical problem of low surgical success rate caused by structural defects in existing self-expanding valve stents during release.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a peripheral adaptive guiding protection structure for implantation of artificial heart valve stents. Background Technology

[0002] Transcatheter aortic valve replacement (TAVR), a significant breakthrough in interventional cardiology, has been widely used in recent years for the clinical treatment of severe aortic stenosis and some selected patients with aortic regurgitation. Compared to traditional open-heart surgery, TAVR, with its advantages of minimal invasiveness, rapid recovery, and no need for cardiopulmonary bypass, has gradually become a first-line treatment option for high-risk and even low-to-intermediate-risk patients. With advancements in equipment and optimization of procedures, the indications for TAVR have expanded from the initial aortic stenosis to aortic regurgitation, providing an effective alternative treatment for more patients who cannot tolerate surgery.

[0003] In TAVR surgery, self-expanding valve stents are widely used due to their excellent radial support and delivery compliance. A typical deployment procedure is as follows: The delivery system, loaded with a compressed valve stent, is advanced via a peripheral vessel to the target location on the aortic annulus. The surgeon precisely manipulates the handle to gradually retract the capsule assembly containing the stent. During this process, the distal end of the stent is first exposed and self-expands, anchoring to the native leaflet and aortic sinus. Subsequently, the capsule assembly continues to retract proximally, and the proximal end of the stent is gradually released until it is completely detached from the capsule assembly and fully expanded, completing the functional valve implantation.

[0004] However, existing technologies present significant risks when dealing with patients with regurgitant aortic valve disease. These patients often exhibit dilated, asymmetrical, or even deep-cavity aortic sinus structures. Simultaneously, the aorta naturally possesses anatomical curvature, causing the capsule assembly to move closely along the greater curvature of the vessel during retraction. Due to this aortic curvature, the outer surface of the capsule assembly eccentrically contacts the vessel wall, resulting in lateral compression from the vessel wall. At this point, the distal stent is largely deployed and anchored, while the proximal stent, still partially within the capsule assembly, has partially expanded but not yet completely detached, creating a protruding metal edge within the capsule assembly that abuts against the inner side of the capsule. This condition makes the capsule assembly highly susceptible to scraping, contact, or jamming with the stent release end during continued retraction. This interference not only directly leads to a sudden increase in capsule retraction resistance and operational difficulties but can also cause serious complications such as abnormal stent movement, stent rotation, skirt tearing, and even paravalvular leakage, significantly impacting the success rate of the procedure. Summary of the Invention

[0005] This invention provides a peripheral adaptive guiding protection structure for implantation of artificial heart valve stents, which solves the technical problem of low surgical success rate caused by structural defects during the release of existing self-expanding valve stents. The specific technical solution is as follows:

[0006] This invention provides a peripheral adaptive guiding protection structure for implantation of artificial heart valve stents, comprising: a core tube, an inner sheath, an outer sheath, a capsule assembly body, an external adaptive folding structure, and a self-expanding valve stent.

[0007] The capsule assembly body includes a capsule cavity that is movably inserted through the core tube. The capsule cavity has a release opening at one end near the distal end of the core tube. The self-expanding valve stent is folded into the capsule cavity and detachably connected to the core tube. The external adaptive folding structure is fixedly disposed on the outer wall of the capsule cavity. The outer sheath is movably sleeved on the core tube and wraps around the capsule assembly body and the external adaptive folding structure. The inner sheath is movably inserted into the outer sheath. The external adaptive folding structure is configured to have a retracted state where it is folded and attached between the outer wall of the capsule cavity and the inner wall of the outer sheath, and an unfolded state where it unfolds radially outward along the capsule cavity and forms a ring surrounding the capsule cavity and the outside of the release opening.

[0008] Optionally, the external adaptive folding structure includes a base, support arms, and a flexible film. The base is fixedly connected to the outside of the capsule cavity. Multiple support arms are provided and are spaced apart on the base along the circumference of the capsule cavity. The support arms extend toward the release opening. The flexible film is laid on the multiple support arms.

[0009] Optionally, the support arm includes a plurality of successively angled bending segments in the extension direction to form a continuously inclined guide surface when the external adaptive anti-folding structure is in the unfolded state.

[0010] Optionally, the bending section includes a root section, a guide section, and a folding-back section. The root section is connected to the base. When the external adaptive folding structure is in the storage state, the folding-back section is bent in the opposite direction and positioned between the guide section and the capsule cavity.

[0011] Optionally, the outer sheath is provided with a traction structure connected to the support arm.

[0012] Optionally, the flexible film is connected to the support arm by bonding, heat sealing, stitching, or injection molding.

[0013] Optionally, the plurality of support arms are arranged at equal angular intervals around the circumference of the capsule cavity.

[0014] Optionally, the base is connected to the outside of the capsule cavity by welding, riveting, snapping, or bonding.

[0015] Optionally, the support arm is made of shape memory alloy or elastic metal.

[0016] Optionally, the flexible film is a polymer elastic coating, a fabric film, or a composite material film.

[0017] Compared with the prior art, the beneficial effects of the embodiments of the present invention include at least the following:

[0018] The peripheral adaptive guiding protection structure for artificial heart valve stent implantation provided in this embodiment of the invention can establish an external physical isolation and guiding mechanism on the outside of the capsule assembly body that does not depend on the internal structure of the stent, does not require a sliding mechanism, and does not occupy the internal cavity space. It can directly form a full-circumferential physical isolation layer on the outside of the stent, blocking direct mechanical contact between the outer edge of the capsule cavity and the release end of the self-expanding valve stent. At the same time, it provides an adaptive continuous guiding path during the retraction phase, thereby significantly reducing the risks of snagging, scratching, stent displacement, and even stent being pulled upward, and improving the controllability, repeatability, and operational stability of the release process. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the peripheral adaptive guiding protection structure for artificial heart valve stent implantation during the delivery stage, as provided in an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the peripheral adaptive guiding protection structure for artificial heart valve stent implantation in the initial stage of the folding phase, as provided in an embodiment of the present invention.

[0021] Figure 3 A schematic diagram of the external adaptive deflection structure provided in an embodiment of the present invention in its unfolded state;

[0022] Figure 4 This is a schematic diagram of the capsule assembly body and the external adaptive anti-folding structure being incorporated into the outer sheath tube according to an embodiment of the present invention.

[0023] Figure 5 A simplified structural diagram of the external adaptive deflection structure provided in the embodiment of the present invention in its unfolded state;

[0024] Figure 6 This is a simplified diagram of the external adaptive anti-folding structure provided in the embodiment of the present invention in its retracted state.

[0025] In the diagram: 1-Core tube; 2-Inner sheath; 3-Outer sheath; 4-Capsule assembly body; 41-Capsule cavity; 42-Release opening; 5-External adaptive folding structure; 51-Base; 52-Support arm; 521-Root segment; 522-Guide segment; 523-Folding segment; 53-Flexible membrane; 6-Self-expanding valve stent. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] In transcatheter aortic valve replacement (TAVR), the deployment of self-expanding stents is typically achieved through a stepwise retraction of the capsule assembly, i.e., deploying the distal end of the stent first, followed by the proximal end. During this process, due to the natural anatomical curvature of the aorta, the capsule assembly tends to move closely along the greater curvature of the vessel during retraction. The lateral compression exerted by the vessel wall on the capsule assembly causes its outer surface to eccentrically adhere to the vessel wall. Simultaneously, the proximal stent, still partially within the capsule assembly, gradually expands outward under the self-expanding force, forming a convex metallic edge that abuts against the inner wall of the capsule assembly. Under the combined effect of the lateral compression from the vessel wall and the medial expansion force of the stent deployment end, the deployment port edge of the capsule assembly is highly susceptible to scraping, abutting, or structurally jamming with the stent deployment end, leading to increased retraction resistance or even complete blockage. This interference not only directly affects the smooth retraction of the capsule but can also lead to abnormal stent movement, stent rotation, skirt tearing, or even stent traction and upward displacement (commonly known as "flying"), seriously threatening intraoperative safety and surgical success rates.

[0028] Existing technologies primarily employ internal guiding structures to mitigate these risks, such as conical kits, sliding guides, or internal supports within the core tube or stent. However, these internal structures, located within the stent cavity, cannot effectively protect the outer edge of the capsule assembly body, nor can they prevent direct physical contact between the outer side of the capsule assembly body and the stent end. Furthermore, the internal guiding structure typically shares a limited internal cavity space with the stent mesh; when the stent undergoes local deformation or deflection within the sinus, the internal guiding structure may interfere with the stent components, introducing new risks.

[0029] To address the aforementioned technical problems, this invention provides a peripheral adaptive guiding protection structure for artificial heart valve stent implantation. Its core concept is to provide an external protective structure on the outer side of the capsule assembly body that automatically unfolds after the outer sheath is withdrawn, adaptively folds back during retraction to form a continuous guiding slope, and automatically folds and stores after entering the sheath. This forms a physical isolation layer directly outside the stent, blocking mechanical contact between the outer edge of the capsule assembly body and the stent release end, and providing active guidance for the retraction of the capsule assembly body.

[0030] Figure 1 This is a schematic diagram of the peripheral adaptive guiding protection structure for artificial heart valve stent implantation during the delivery stage, as provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the peripheral adaptive guiding protection structure for artificial heart valve stent implantation in the initial stage of the folding phase, as provided in an embodiment of the present invention. Figure 3 A schematic diagram of the external adaptive deflection structure provided in an embodiment of the present invention in its unfolded state; Figure 4 This is a schematic diagram of the capsule assembly body and the external adaptive anti-folding structure being incorporated into the outer sheath tube according to an embodiment of the present invention; Figure 5 A simplified structural diagram of the external adaptive deflection structure provided in the embodiment of the present invention in its unfolded state; Figure 6 This is a simplified structural diagram of the external adaptive anti-folding structure provided in an embodiment of the present invention in its retracted state. Figures 1 to 6 As shown, this embodiment of the invention provides a peripheral adaptive guiding protection structure for implantation of artificial heart valve stents, including a core tube 1, an inner sheath 2, an outer sheath 3, a capsule assembly body 4, an external adaptive folding structure 5, and a self-expanding valve stent 6.

[0031] The core tube 1 is a slender tubular component extending axially, passing through the center of the delivery system. It serves to transmit force, guide the path, and position the stent throughout the delivery, release, and retraction process. The distal end of the core tube 1 has a detachable fixation structure for secure connection to the proximal end of the self-expanding valve stent 6. This detachable fixation structure ensures that the core tube 1 and the self-expanding valve stent 6 remain integrally connected during release and deployment, providing axial constraint and radial positioning for the self-expanding valve stent 6 during the release phase to prevent uncontrolled movement of the stent during deployment. Once the self-expanding valve stent 6 is fully deployed and the implantation position is confirmed, the operator uses a control device to disconnect the distal end of the core tube 1 from the self-expanding valve stent 6, thus separating the two.

[0032] The inner sheath 2 is movably inserted inside the outer sheath 3 and is slidably arranged along the axial direction of the core tube 1. The inner sheath 2 is used to provide auxiliary support and protection for the capsule assembly body 4 and its internal self-expanding valve stent 6 during the delivery stage, ensuring that the capsule assembly body 4 and its internal self-expanding valve stent 6 are always at the distal end of the outer sheath 3, making it easy to expose and release outwards. During the release operation, it coordinates with the relative movement of the outer sheath 3 and the core tube 1 to control the release rhythm of the stent.

[0033] The outer sheath 3 is movably fitted onto the core tube 1 and, during delivery, encloses the capsule assembly body 4 and the external adaptive folding structure 5. During delivery, the outer sheath 3 provides radial constraint on the capsule assembly body 4, the self-expanding valve stent 6, and the external adaptive folding structure 5, maintaining the entire delivery assembly in a low-profile configuration for passage through peripheral blood vessels. Upon reaching the target location, the outer sheath 3 is retracted via a control device to gradually expose the capsule assembly body 4 and the external adaptive folding structure 5, thereby initiating the release process of the self-expanding valve stent 6 and the abduction process of the external adaptive folding structure 5.

[0034] The capsule assembly body 4 includes a capsule cavity 41 movably inserted into the core tube 1. The capsule cavity 41 is a tubular shell structure extending axially along the core tube 1, and its interior forms an encapsulation space for accommodating the self-expanding valve stent 6 in a compressed state. The capsule cavity 41 has a release opening 42 at its distal end near the core tube 1. This release opening 42 is an axial end opening of the capsule cavity 41, through which the self-expanding valve stent 6 gradually dislodges from the capsule cavity 41 during release. In this embodiment, the distal end of the self-expanding valve stent 6 releases before the proximal end, therefore the release opening 42 is located at the distal end of the capsule cavity 41. When the capsule cavity 41 retracts in the proximal direction, the self-expanding valve stent 6 sequentially exposes its distal to proximal ends from the release opening 42, gradually unfolding to a predetermined shape under the action of self-expanding force.

[0035] The self-expanding valve stent 6 is folded and disposed within the capsule cavity 41 and is detachably connected to the core tube 1. The self-expanding valve stent 6 can be made of materials with superelastic or shape memory properties, such as nickel-titanium alloy, and is placed into the capsule cavity 41 after being compressed and loaded in vitro. The self-expanding valve stent 6 remains compressed while constrained by the capsule cavity 41. Once it is freed from the radial constraint of the capsule cavity 41, it automatically expands and unfolds to its memory shape under the action of its own elastic restoring force, anchoring itself to the aortic valve annulus and its surrounding tissues.

[0036] An external adaptive deflection structure 5 is fixedly mounted on the outer wall of the capsule cavity 41. Specifically, the external adaptive deflection structure 5 is fixedly installed on the outer peripheral surface of the capsule cavity 41 near the release opening 42. The external adaptive deflection structure 5 is configured to have two operating states:

[0037] The first configuration is the retracted state, in which the external adaptive anti-folding structure 5 is folded and attached between the outer wall of the capsule cavity 41 and the inner wall of the outer sheath 3. In the retracted state, the overall outer diameter of the external adaptive anti-folding structure 5 does not exceed the inner diameter of the outer sheath 3, allowing the delivery assembly to maintain a low profile during advancement and withdrawal, without increasing the overall outer diameter of the transvascular delivery or affecting intravascular permeability. In this state, the external adaptive anti-folding structure 5 is held in place by the radial space between the outer sheath 3 and the capsule cavity 41, resulting in a passively compressed folded configuration.

[0038] The second state is the unfolded state. In this state, the external adaptive counter-folding structure 5 unfolds radially outward along the capsule cavity 41 and forms a ring surrounding the capsule cavity 41 and the outside of the release opening 42. When the outer sheath 3 retracts, causing the external adaptive counter-folding structure 5 to break free from the radial constraint of the outer sheath 3, the external adaptive counter-folding structure 5 automatically unfolds outward under the drive of its own elastic restoring force, forming an isolation interface surrounding the outside of the release opening 42 of the capsule cavity 41. This isolation interface establishes a stable physical gap between the outer surface of the capsule cavity 41 and the blood vessel wall, so that the outer side of the capsule cavity 41 no longer directly faces the blood vessel wall exerting lateral pressure due to the bending of the aorta. Thus, the external adaptive counter-folding structure 5 effectively disperses and isolates the lateral clamping force of the blood vessel wall on the capsule cavity 41, avoiding mechanical interference between the outer edge of the capsule cavity 41 and the release end of the self-expanding valve stent 6 under the combined action of blood vessel wall compression force and stent expansion force. This fundamentally reduces the risk of scraping, entrapment, and stent traction, and significantly improves the safety and controllability of the stent release process.

[0039] During operation of the delivery system, the self-expanding valve stent 6 is first compressed and loaded into the capsule cavity 41 externally. The external adaptive folding structure 5 is pre-pressed against the outer surface of the capsule cavity 41 and, together with the capsule assembly body 4, is inserted into the outer sheath 3 to form an integrated delivery assembly. After establishing access via femoral artery or other suitable vascular pathways, the delivery assembly is advanced along the blood vessel to the vicinity of the target position at the aortic root under the guidance of a guidewire. During this advancement, the external adaptive folding structure 5 remains within the clamping space between the outer sheath 3 and the capsule cavity 41, maintaining a low profile in its retracted state and not causing additional occupancy of the blood vessel diameter. Upon reaching the target position, the outer sheath 3 is retracted via a control device, exposing the capsule assembly body 4 and the self-expanding valve stent 6; subsequently, the capsule cavity 41 is gradually pulled back proximally, allowing the distal end of the self-expanding valve stent 6 to be released and deployed first.

[0040] When the outer sheath 3 retracts, causing the segment of the external adaptive folding structure 5 to first escape the radial compression of the outer sheath 3, the external adaptive folding structure 5 gradually unfolds outward under the drive of elastic restoring force, changing from a retracted state to an unfolded state, forming an external isolation interface surrounding the release opening 42 of the capsule cavity 41. At this time, this external isolation interface is located axially at the end of the self-expanding valve stent 6 still inside the capsule cavity 41 and on the outside of the capsule cavity 41, pushing the nearby blood vessel wall outward and establishing a gap between the blood vessel wall and the capsule cavity 41, maintaining a safe distance between the two and avoiding direct contact or hard collision.

[0041] As the capsule cavity 41 continues to retract proximally to release the proximal end of the self-expanding valve stent 6, the external adaptive folding structure 5, under the combined influence of the external tension at the release end of the self-expanding valve stent 6, the blood flow force, and the movement tendency of the capsule cavity 41 itself, adaptively transforms from an deployed isolation state to a folding guide state, forming a continuously inclined guide surface. This guide surface causes the capsule cavity 41 to slide along the guide surface during retraction, and its movement direction is guided to deflect away from the end of the self-expanding valve stent 6, thereby achieving active correction of the retraction path and allowing the capsule cavity 41 to smoothly cross the already deployed proximal structure of the self-expanding valve stent 6, completing a smooth separation.

[0042] After the self-expanding valve stent 6 is fully deployed and its position is confirmed to be satisfactory, the capsule assembly body 4 and its external adaptive folding structure 5 are retracted proximally into the outer sheath 3 via a control device. Under the uniform radial compression of the inner wall of the outer sheath 3, the external adaptive folding structure 5 is passively compressed and adhered to the outer wall of the capsule cavity 41, restoring its low-profile shape in the retracted state, thus achieving smooth withdrawal of the delivery system. Because the external adaptive folding structure 5 can naturally fold back and adhere tightly to the outer wall of the capsule cavity 41 within the outer sheath 3, the overall outer diameter does not increase the catheter's outer diameter, and has no adverse effects on vascular navigation, aortic arch crossing, or other operations.

[0043] Through the above structural configuration, this embodiment establishes an external physical isolation and guidance mechanism on the outside of the capsule assembly body 4 that does not rely on the internal structure of the stent, does not require a sliding mechanism, and does not occupy the internal cavity space. It can directly form a full-circumference physical isolation layer on the outside of the stent, blocking the direct mechanical contact between the outer edge of the capsule cavity 41 and the release end of the self-expanding valve stent 6. At the same time, it provides an adaptive continuous guidance path during the retraction phase, thereby significantly reducing the risks of snagging, scratching, stent displacement, and even the stent being pulled upward, and improving the controllability, repeatability, and operational stability of the release process.

[0044] Furthermore, the external adaptive retraction structure 5 includes a base 51, a support arm 52, and a flexible film 53. The base 51 is fixedly connected to the outside of the capsule cavity 41. In this embodiment, the base 51 is an annular or semi-annular fixing member disposed on the outer wall of the capsule cavity 41. It serves as the connection basis between the entire external adaptive retraction structure 5 and the capsule assembly body 4, and is used to stably anchor the support arm 52 to the capsule cavity 41, ensuring that the external adaptive retraction structure 5 has a reliable mechanical connection throughout the entire process of deployment, retraction, and sheath retraction. The base 51 is preferably located on the outer wall of the capsule cavity 41 near the release opening 42, so that after deployment, the isolation interface of the external adaptive retraction structure 5 can cover the area where the outer edge of the capsule cavity 41 is most likely to interfere with the release end of the self-expanding valve stent 6.

[0045] Multiple support arms 52 are provided and are circumferentially connected to the base 51. Each support arm 52 extends from the base 51 toward the release opening 42, that is, it extends axially toward the distal end of the capsule cavity 41 or extends at a slightly radially outward angle. The multiple support arms 52 are arranged circumferentially around the capsule cavity 41 to form a skeleton structure surrounding the capsule cavity 41. The support arms 52 are the core load-bearing components of the external adaptive anti-folding structure 5. They are responsible for supporting the flexible film 53 outward to form an isolation interface in the unfolded state, and for causing the flexible film 53 to flip through elastic bending deformation during the anti-folding process to form a guide slope. In the retracted state, each support arm 52 is radially compressed and attached to the outer wall of the capsule cavity 41 by the outer sheath tube 3, maintaining a low profile shape together with the flexible film 53; in the unfolded state, each support arm 52 opens outward under the drive of elastic restoring force, and the flexible film 53 unfolds outward accordingly, forming an annular isolation surface outside the release opening 42.

[0046] A flexible film 53 is laid on multiple support arms 52. The flexible film 53 covers the gaps between adjacent support arms 52, so that the multiple support arms 52 and the flexible film 53 together form a continuous deformable interface. In the unfolded state, the flexible film 53 unfolds between each support arm 52 to form a continuous planar isolation structure, so that the isolation interface is not limited to the local direction where each support arm 52 is located, but forms a circumferential continuous coverage with a high degree of closure, thereby achieving full circumferential physical isolation between the outer edge of the capsule cavity 41 and the release end of the self-expanding valve stent 6. In the folding stage, the flexible film 53 flips synchronously with the bending deformation of the support arms 52, so that the guide surface maintains planar continuity. When the capsule cavity 41 retracts, it contacts the continuous guide surface and slides smoothly along it, thereby avoiding the risk of local snagging caused by gaps in the guide surface.

[0047] Through the coordinated operation of the base 51, support arms 52, and flexible membrane 53, the external adaptive anti-folding structure 5 forms a complete "skeleton-membrane" external protection system: the base 51 provides a stable connection foundation, multiple support arms 52 constitute a deformable support skeleton, and the flexible membrane 53 fills the spaces between the skeletons to form a continuous isolation and guiding interface. When deployed, the structure resembles an unfolded umbrella shape, forming an annular protective space outside the capsule cavity 41; during anti-folding guidance, the flexible membrane 53 naturally transitions from an isolation surface to a continuously inclined guiding surface, guiding the capsule cavity 41 to smoothly cross the release edge of the self-expanding valve stent 6.

[0048] Furthermore, the support arm 52 includes multiple successively angled bending segments in its extension direction to form a continuously inclined guide surface when the external adaptive anti-folding structure 5 is in the unfolded state. Specifically, the support arm 52 is not a straight rod with a uniform cross-section, but rather has multiple segments bent at different angles along its extension direction from the base 51 to the free end. In the retracted state during the conveying stage, each bending segment is radially compressed by the outer sheath 3 and is in an approximately straight-line attached state; when the outer sheath 3 is retracted, each bending segment recovers its preset bending angle under the drive of the support arm 52's own elasticity or shape memory characteristics, thereby making the entire support arm 52 present a spatial configuration of multiple broken lines or smooth curves in the unfolded state.

[0049] During the retraction of the capsule cavity 41, when the external adaptive folding structure 5 is subjected to the external tension at the release end of the self-expanding valve stent 6 and the reaction force generated by the retraction movement of the capsule cavity 41, each bending segment of the support arm 52 undergoes controlled elastic bending deformation under the action of the aforementioned forces. The bending angle of each bending segment is gradually adjusted under the action of external forces, so that the support arm 52 as a whole adaptively transitions from an outwardly isolated configuration to an inclined guiding configuration. The flexible membrane 53 moves synchronously with the deformation of each bending segment, forming a continuous inclined guiding surface between multiple support arms 52. The curvature and tilt angle of this guiding surface are not fixed, but can be automatically adjusted according to changes in factors such as the degree of deployment of the self-expanding valve stent 6, the curvature of the blood vessel, and the retraction speed of the capsule cavity 41. Thus, under various complex anatomical and operational conditions such as aortic sinus dilation, irregular deep sinus structure, supravalvular calcification, significant bending of the ascending aorta, and slight drift of the self-expanding valve stent 6, it always provides a stable and continuous guiding sliding path for the capsule cavity 41.

[0050] Compared to existing technologies that use fixed-angle or rigid guides, the bent section structure of this embodiment allows the formation of the guide surface to be independent of any independent mechanical mechanism or sliding fit, but is entirely based on the elastic geometric deformation of the support arm 52 itself. Therefore, it has higher adaptability and stronger robustness, and can maintain the smoothness and predictability of the guiding action even under extreme anatomical conditions.

[0051] Optionally, the bending segment includes a root segment 521, a guide segment 522, and a retraction segment 523. The root segment 521 is connected to the base 51 and is the connecting segment of the support arm 52 near the capsule cavity 41. The root segment 521 and the base 51 form a rigid or semi-rigid connection to provide a stable anchoring foundation and support stiffness for the support arm 52 throughout the unfolding and retraction process. The root segment 521 undertakes the main support function, enabling the support arm 52 to resist the radial pressure of the blood vessel wall when unfolding and maintain the outward configuration of the flexible membrane 53.

[0052] The guide segment 522 is connected to the distal end of the root segment 521 and is the middle section of the support arm 52 along its extension direction. The guide segment 522 is designed to be flexible, meaning its bending stiffness is lower than that of the root segment 521. This design ensures that during the retraction of the capsule cavity 41, when the reverse load is transmitted to the support arm 52 via the flexible membrane 53, the guide segment 522 preferentially undergoes elastic bending deformation, becoming the main area where the overall bending deformation of the support arm 52 occurs. The flexible characteristic of the guide segment 522 can be achieved by reducing its cross-sectional size, changing its cross-sectional shape (e.g., using a flat cross-section), setting local slots, or using a variable cross-section design, enabling it to produce controllable progressive bending under stress conditions.

[0053] The reversing section 523 is connected to the distal end of the guide section 522 and is the farthest working section of the support arm 52. The reversing section 523 is located close to the release edge of the self-expanding valve stent 6 and plays a key role in forming the guide slope. The reversing section 523 can form a repeatable "articulated bending zone" by preset bending angle, pre-formed curvature, or by using variable cross-section, grooving, local heat treatment, etc.

[0054] In this embodiment, when the external adaptive folding structure 5 is in the retracted state, the folding segment 523 is bent in the opposite direction and positioned between the guide segment 522 and the capsule cavity 41. That is, in the retracted state, the folding segment 523 does not continue to extend distally along the extension direction of the guide segment 522, but instead bends inward from the end of the guide segment 522 and adheres to the space between the guide segment 522 and the capsule cavity 41. This pre-configured design ensures that in the retracted state, the folding segment 523 is housed inside the guide segment 522, without increasing the radial space occupied by the external adaptive folding structure 5, thus helping to maintain a low profile.

[0055] After the outer sheath 3 retracts, the external adaptive folding structure 5 unfolds, and the folding section 523 unfolds outward along with the support arm 52. During the subsequent retraction of the capsule cavity 41, the leading edge of the flexible membrane 53 generates a reaction force due to the obstruction of the release end of the self-expanding valve stent 6. This reaction force is transmitted through the flexible membrane 53 to the free end of the support arm 52 (i.e., the area where the folding section 523 is located), forming a torque near the root section 521, causing the guide section 522 and the folding section 523 to bend sequentially. During this process, the folding section 523, which is pre-bent in the reverse direction and located inside the guide section 522, is pushed out of the guide section 522 and unfolds outward relative to the end of the guide section 522 by the capsule cavity 41 pushed outward by the release end of the self-expanding valve stent 6, thus naturally transitioning from the outward-extending isolation surface to a continuously inclined guide surface. During the unfolding process, the pre-set bending curvature of the folding section 523 naturally forms a smooth guide surface with a gradually changing slope, guiding the capsule cavity 41 to slide smoothly along the guide surface and smoothly cross the release end edge of the self-expanding valve stent 6, thus achieving adaptive folding guidance.

[0056] It is important to note that the aforementioned folding process is not actively driven, but rather triggered by the elastic geometric deformation resulting from the relative motion and contact reaction force of the capsule cavity 41 in the retraction direction. The entire deformation chain is automatically completed based entirely on the elastic characteristics and spatial geometry of each segment of the support arm 52, without the need for additional button drives, internal push-pull mechanisms, or independent sliding parts to achieve shape transformation. This passive adaptive working method significantly simplifies the operation process, eliminating reliance on operator adjustments to the delivery system's angle or other skillful operations, lowering the operational threshold, and improving the consistency and reliability of operations among different operators.

[0057] Optionally, the outer sheath 3 is provided with a traction structure connected to the support arm 52. This traction structure can be a traction line, traction wire, or other flexible control component, with one end connected to a suitable position on the support arm 52 and the other end extending to the outer sheath 3 or the control handle side. Through this traction structure, the operator can actively retract the support arm 52 inwards when needed, causing the flexible film 53 to fold and retract, so that the external adaptive anti-folding structure 5 returns from its unfolded state to a retracted state or a nearly retracted folded configuration. Subsequently, the outer sheath 3 is pushed further outwards to cover the retracted external adaptive anti-folding structure 5.

[0058] The traction structure enables the external adaptive folding structure 5 to retract into its sheath during release and retraction. In clinical practice, if unsatisfactory positioning occurs during the release of the self-expanding valve stent 6, requiring readjustment of the system's posture or repositioning, the operator can actively retract the external adaptive folding structure 5 using the traction structure and reintegrate it into the outer sheath 3, thereby resetting the delivery system's posture and facilitating subsequent re-release. This retraction process can be coordinated with the advancement and retraction of the outer sheath 3, making the operation simple and requiring no additional complex control mechanisms.

[0059] Optionally, the flexible film 53 and the support arm 52 are connected by methods such as bonding, heat sealing, sewing, or injection molding. Specifically, the edge of the flexible film 53 or the area corresponding to the position of the support arm 52 is fixedly connected to each support arm 52, so that the flexible film 53 always moves synchronously with the support arm 52 during the unfolding and bending deformation of the support arm 52, maintaining the integrity of the continuous guiding interface. Bonding can be achieved by using medical-grade adhesive to firmly bond the corresponding area of ​​the flexible film 53 to the surface of the support arm 52; heat sealing uses local heating to fuse the flexible film 53 material to the surface of the support arm 52; sewing uses medical sutures to sew and fix the flexible film 53 to the support arm 52; injection molding directly coats the flexible film 53 material onto the outer surface of the support arm 52 during the molding process, forming an integrated connection structure. The optimal connection method can be selected based on the material characteristics of the flexible film 53 and the support arm 52, or multiple connection methods can be combined to improve connection reliability. A reliable connection ensures that the flexible film 53 will not detach from or lift off the support arm 52 during outward and folding processes, thereby reducing the risk of snagging caused by the edge of the flexible film 53 lifting and maintaining the continuity and integrity of the isolation and guidance interface.

[0060] Optionally, multiple support arms 52 are arranged at equal angular intervals around the circumference of the capsule cavity 41. That is, the support arms 52 are arranged radially and evenly distributed on the cross-sectional projection of the capsule cavity 41, and the circumferential angular interval between adjacent support arms 52 is equal. For example, when there are 3 support arms 52, the circumferential interval angle between adjacent support arms 52 is 120°; when there are 4, the interval angle is 90°; and when there are 6, the interval angle is 60°.

[0061] The equiangularly spaced support arms 52 create a circumferentially uniform isolation and guidance interface for the external adaptive anti-reflection structure 5 in its deployed state. The isolation and guidance capabilities are consistent in all directions, eliminating localized weak points caused by uneven distribution of the support arms 52. This uniform arrangement is particularly important for dealing with unpredictable radial force distribution within the blood vessel lumen, as the direction and degree of aortic curvature vary depending on individual patient differences in the clinical setting, and the direction of lateral compressive force on the capsule cavity 41 is not always predictable. The equiangularly spaced support arms 52 ensure that the external adaptive anti-reflection structure 5 provides stable isolation and guidance support in any radial direction, regardless of the rotational posture and eccentricity of the capsule cavity 41 within the blood vessel.

[0062] In some alternative implementations, the support arms 52 may also be arranged in a non-uniform manner according to specific clinical needs. For example, the distribution density of the support arms 52 may be increased in the direction in which the capsule cavity 41 is expected to be mainly eccentrically attached, so as to provide stronger isolation support in that direction. Those skilled in the art can flexibly choose the number and arrangement of the support arms 52 according to actual needs.

[0063] Optionally, the base 51 is connected to the outside of the capsule cavity 41 by welding, riveting, snap-fitting, or adhesive bonding. As the only fixed connection point between the external adaptive anti-folding structure 5 and the capsule assembly body 4, the strength and reliability of the base 51 directly determine the stability of the external adaptive anti-folding structure 5 throughout its operation. Welding (e.g., laser welding or resistance welding) can form a high-strength metallurgical bond between the base 51 and the outer wall of the capsule cavity 41, suitable for bases made of metal. Riveting uses mechanical rivets to lock the base 51 onto the capsule cavity 41, providing a strong connection and facilitating assembly and inspection. Snap-fitting achieves a reliable connection by using mutually cooperating fastening structures on the base 51 and the capsule cavity 41, suitable for situations requiring positioning adjustments during assembly. Adhesive bonding uses medical-grade adhesive to fix the base 51 to the outer wall of the capsule cavity 41, suitable for situations where the materials of the base 51 and the capsule cavity 41 differ and direct welding is not suitable.

[0064] In this embodiment, the base 51 can be a ring structure, a semi-ring structure, or a multi-point fixing structure. When the base 51 is a ring structure, it is arranged around the outer wall of the capsule cavity 41, providing a circumferentially continuous connection base for all support arms 52, so that the deployment behavior of each support arm 52 is highly consistent in the circumferential direction. When the base 51 is a semi-ring or multi-point fixing structure, it only covers a portion of the circumferential area of ​​the capsule cavity 41 or sets fixing nodes at several discrete points on the outer wall of the capsule cavity 41, and each support arm 52 is connected to the corresponding fixing node. The base 51 can also be used to limit the deployment angle and deployment stroke of the support arm 52. For example, by setting a limiting structure at the connection between the base 51 and the support arm 52, the support arm 52 is prevented from extending excessively beyond the expected working range, thereby ensuring that the isolation and guiding surface formed by the flexible film 53 accurately covers the area most prone to interference between the outer edge of the capsule cavity 41 and the release end of the self-expanding valve stent 6.

[0065] Optionally, the support arm 52 is made of shape memory alloy or elastic metal. In a preferred embodiment, the support arm 52 is made of nickel-titanium alloy (NiTi). Nickel-titanium alloy has excellent superelasticity and shape memory properties. Under body temperature conditions (approximately 37°C), it is in the austenitic phase and can produce fully recoverable elastic deformation over a large strain range. This characteristic allows the support arm 52, after being radially compressed by the outer sheath 3 to a retracted state attached to the outer wall of the capsule cavity 41, to automatically return to the preset outward configuration under its own superelastic restoring force once the outer sheath 3 is withdrawn and the radial constraint is released, without any external driving force. At the same time, during the anti-folding guidance stage, the superelasticity of the nickel-titanium alloy keeps the bending deformation of the support arm 52 within the elastic range, and it can automatically spring back to its original shape after the external force is removed, ensuring the reusability and predictability of shape recovery of the external adaptive anti-folding structure 5.

[0066] In another embodiment, the support arm 52 can be made of an elastic metal material, such as stainless steel spring wire or cobalt-chromium alloy elastic wire. These materials also have a high elastic limit and good fatigue life, which can meet the mechanical requirements of the support arm 52 during repeated storage and deployment.

[0067] The specific number of support arms 52 can be selected according to the diameter of the delivery system and clinical application requirements, for example, it can be set to 2, 3, 4, 6 or more. A larger number of support arms 52 can provide more uniform circumferential coverage and finer skeleton support, making the planar isolation of the flexible membrane 53 more complete; a smaller number of support arms 52 can help reduce radial profile occupation and simplify the structure.

[0068] Optionally, the flexible film 53 is a polymer elastic coating, a fabric film, or a composite material film. In a preferred embodiment, the flexible film 53 is made of expanded polytetrafluoroethylene (ePTFE) film. ePTFE film has excellent blood compatibility, chemical inertness, and biological stability. Its microporous structure combines flexibility and mechanical strength, enabling it to maintain structural integrity during repeated folding and unfolding without irritating or damaging the blood vessel wall or contacting tissue.

[0069] In another embodiment, the flexible film 53 can be a thermoplastic polyurethane (TPU) film. TPU films have good elasticity, high elongation, and excellent tear resistance, maintaining planar continuity without tearing when the flexible film 53 needs to undergo significant deformation following the support arm 52. In yet another embodiment, the flexible film 53 can be a silicone rubber film, which has excellent flexibility and biocompatibility, making it suitable for applications requiring high softness and fit. In a further embodiment, the flexible film 53 can also be a multilayer composite polymer film or fabric film (e.g., polyester fabric film, nylon fabric film) to achieve a balance of strength, flexibility, and fatigue resistance through a multilayer composite structure.

[0070] The material selection for the flexible membrane 53 should simultaneously meet the following requirements: sufficient flexibility to follow the bending deformation of the support arm 52 without cracking; sufficient mechanical strength to resist blood flow impact and contact friction during unfolding and folding without tearing; good blood compatibility to reduce adverse effects on blood components and vascular tissues; and good fatigue resistance to withstand repeated folding and unfolding mechanical cycles. Those skilled in the art can select the most suitable material for the flexible membrane 53 based on the specific delivery system specifications and clinical indication requirements.

[0071] In some embodiments, during release and retraction, the distal end of the core tube 1 can still maintain traction and positioning association with the end of the self-expanding valve stent 6, ensuring the stability of the self-expanding valve stent 6 during the critical release phase. When abnormal resistance occurs during the retraction of the capsule cavity 41, the operator can perform a short reverse advance (i.e., push the capsule cavity 41 slightly distally back) to release the contact, and then adjust the system posture before retracting again to improve the stability and controllability of the crossing. This operation, combined with the adaptive guidance function of the external adaptive anti-folding structure 5, can further reduce the operational risks under complex anatomical conditions.

[0072] In some embodiments, when the blood vessel diameter is large or the proximal structure of the self-expanding valve stent 6 is more complex, the number of support arms 52 can be appropriately increased or the coverage width of the flexible film 53 can be increased to increase the isolation interface area and ensure sufficient coverage of the interference area between the outer edge of the capsule cavity 41 and the release end of the self-expanding valve stent 6. If it is desired to further reduce the overall outer diameter occupancy, the cross-sectional dimensions of the support arms 52 can be reduced or a higher-strength material can be selected to maintain sufficient support force while reducing the radial space occupancy. Those skilled in the art can optimize the structural parameters based on the above embodiments, all of which are reasonable variations of the disclosure of this invention.

[0073] It should be noted that, in the description of this invention, the term "distal" refers to the direction farther from the operator and closer to the heart in the transcatheter delivery path; the term "proximal" refers to the direction closer to the operator in the transcatheter delivery path. The term "axial" refers to the direction along the central axis of the core tube 1; the term "radial" refers to the direction perpendicular to the central axis of the core tube 1; and the term "circumferential" refers to the direction surrounding the central axis of the core tube 1. The above directional limitations are only used to explain the relative positional relationship between the components and do not constitute a limitation on the scope of protection of this invention.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A peripheral adaptive guiding protection structure for implantation of artificial heart valve stents, characterized in that, include: Core tube (1), inner sheath (2), outer sheath (3), capsule assembly body (4), external adaptive folding structure (5), and self-expanding valve stent (6). The capsule assembly body (4) includes a capsule cavity (41) movably inserted through the core tube (1). The capsule cavity (41) has a release opening (42) at one end near the distal end of the core tube (1). The self-expanding valve stent (6) is folded inside the capsule cavity (41) and detachably connected to the core tube (1). The external adaptive anti-folding structure (5) is fixedly disposed on the outer wall of the capsule cavity (41). The outer sheath (3) is movably sleeved on the core tube (1). The capsule assembly body (4) and the external adaptive folding structure (5) are wrapped around the capsule assembly body (41) and the external adaptive folding structure (5). The inner sheath (2) is movably inserted into the outer sheath (3). The external adaptive folding structure (5) is configured to have a folded and attached storage state between the outer wall of the capsule cavity (41) and the inner wall of the outer sheath (3), and an unfolded state that unfolds radially outward along the capsule cavity (41) and surrounds the capsule cavity (41) and the outside of the release opening (42). The external adaptive anti-folding structure (5) includes a base (51), a support arm (52), and a flexible film (53). The base (51) is fixedly connected to the outside of the capsule cavity (41). The support arm (52) is provided in multiple and is connected to the base (51) at intervals along the circumference of the capsule cavity (41). The support arm (52) extends toward the release opening (42). The flexible film (53) is laid on the multiple support arms (52). The support arm (52) includes multiple bending segments that are bent at angles in sequence in the extension direction, so as to form a continuously inclined guide surface when the external adaptive anti-folding structure (5) is in the unfolded state. The bending section includes a root section (521), a guide section (522), and a folding section (523). The root section (521) is connected to the base (51). When the external adaptive folding structure (5) is in the storage state, the folding section (523) is bent in the opposite direction and disposed between the guide section (522) and the capsule cavity (41).

2. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to claim 1, characterized in that, The outer sheath (3) is provided with a traction structure that is connected to the support arm (52).

3. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to claim 1, characterized in that, The flexible film (53) is connected to the support arm (52) by bonding, heat sealing, sewing or injection molding.

4. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to claim 1, characterized in that, The multiple support arms (52) are arranged at equal angular intervals around the capsule cavity (41) in the circumferential direction.

5. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to any one of claims 1 to 4, characterized in that, The base (51) is connected to the outside of the capsule cavity (41) by welding, riveting, snapping or bonding.

6. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to any one of claims 1 to 4, characterized in that, The support arm (52) is made of shape memory alloy or elastic metal.

7. The peripheral adaptive guiding protection structure for implantation of artificial heart valve stents according to any one of claims 1 to 4, characterized in that, The flexible film (53) is a polymer elastic film, a fabric film, or a composite material film.

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