US-20260124033-A1 - ARTIFICIAL HEART VALVE

US20260124033A1US 20260124033 A1US20260124033 A1US 20260124033A1US-20260124033-A1

Abstract

An artificial heart valve includes a stent, a leaflet assembly, an inner skirt, and an outer skirt. The stent includes an inflow end, an outflow end, and stent holes. The outer skirt includes a closing part, a free part, and a connecting part. The closing part is close to the inflow end and connects to the inner skirt. The free part is connected to the closing part and extends away from the inflow end. The connecting part connects to a portion of the free part close to the outflow end and connects to the stent and/or the inner skirt at the same time. Backflow blood can flow through the stent holes located between the outflow end and an inflow edge of the leaflet assembly and flows into the free part. The free part can swell away from the stent under pressure of the backflow blood to abut against surrounding tissues.

Inventors

Gui ZHANG
Luyao FANG
Deyuan Zhang

Assignees

BIOTYX MEDICAL (SHENZHEN) CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20230928
Priority Date: 20220930

Claims (19)

1 .- 18 . (canceled)
19 . An artificial heart valve, comprising: a stent comprising an inflow end and an outflow end, wherein a plurality of stent holes are formed in the stent; a leaflet assembly arranged in the stent, wherein the leaflet assembly has an inflow edge facing the outflow end; an inner skirt arranged on an inner surface of the stent, wherein the inner skirt comprises an inflow skirt edge close to the inflow end and an outflow skirt edge close to the outflow end, and the inner skirt is connected to the inflow edge; and an outer skirt, at least partially arranged at an outer periphery of the stent, wherein the outer skirt comprises a closing part, a free part, and a connecting part; the closing part is arranged outside the stent and is close to the inflow end; the closing part is connected to the inner skirt; the free part is connected to the closing part and extends in a direction away from the inflow end; the connecting part is connected to a portion of the free part close to the outflow end, and the connecting part is connected to the stent and/or the inner skirt; backflow blood flows through the stent holes located between the outflow end and the inflow edge and flows into the free part; the free part swells in a direction away from the stent under pressure of the backflow blood to abut against surrounding tissues and achieve sealing.
20 . The artificial heart valve according to claim 19 , wherein an axial distance between the closing part and the inflow end is A1; a minimum axial distance between the inflow edge and the inflow end is B1; an axial distance between the inflow skirt edge and the inflow end is C1; an axial distance between the outflow skirt edge and the inflow end is C2; and A ⁢ 1 ≤ B ⁢ 1 , C ⁢ 1 < A ⁢ 1 , C ⁢ 2 > B ⁢ 1 ; or , A ⁢ 1 > B ⁢ 1 , C ⁢ 1 < B ⁢ 1 , C ⁢ 2 > A ⁢ 1 .
21 . The artificial heart valve according to claim 20 , wherein A1 is greater than or equal to 1% of a nominal length of the stent and less than or equal to 49% of the nominal length of the stent.
22 . The artificial heart valve according to claim 20 , wherein an axial distance between an extending end of the free part after swelling and the inflow end is A2, and a difference between A2 and B1 is greater than or equal to 30% of a nominal length of the stent and less than or equal to 74% of the nominal length of the stent.
23 . The artificial heart valve according to claim 19 , wherein a radial extension of the free part after swelling is greater than or equal to 5% of a nominal diameter of the stent and less than or equal to half of a nominal length of the stent.
24 . The artificial heart valve according to claim 19 , wherein an axial distance between an extending end of the free part after swelling and the closing part is L; an axial distance between the outflow end and the closing part is H; and a length of the free part is greater than or equal to L and less than or equal to (H−1/2L)π.
25 . The artificial heart valve according to claim 19 , wherein a thickness of the free part is greater than or equal to 5 μm and less than or equal to 200 μm.
26 . The artificial heart valve according to claim 19 , wherein the connecting part comprises a first connecting sub-part and a second connecting sub-part which are connected to each other; or the connecting part comprises a first connecting sub-part, a second connecting sub-part, and an extending sub-part, and two ends of the extending sub-part are respectively connected to the first connecting sub-part and the second connecting sub-part; and the first connecting sub-part is connected to the free part; and the second connecting sub-part is connected to the stent and/or the inner skirt.
27 . The artificial heart valve according to claim 26 , wherein there are a plurality of connecting parts; the plurality of connecting parts are arranged in a spacing manner in a circumferential direction of the free part; or, in the same connecting part, there are a plurality of first connecting sub-parts.
28 . The artificial heart valve according to claim 27 , wherein an axial distance between at least one of the first connecting sub-parts and an extending end of the free part is greater than or equal to 0 and less than or equal to 10 mm.
29 . The artificial heart valve according to claim 27 , wherein at least one of the first connecting sub-parts is strip-shaped or ringlike from a top-view surface; and by taking a center of the stent as a vertex, an angle between two ends of the strip-shaped first connecting sub-part from the top-view surface is greater than or equal to 120° and less than 360°; or at least two adjacent first connecting sub-parts are point-like from the top-view surface; and by taking the center of the stent as the vertex, an angle between the two first connecting sub-parts from the top-view surface is greater than or equal to 120° and less than or equal to 240°.
30 . The artificial heart valve according to claim 26 , wherein a length of the extending sub-part is greater than 0 and less than or equal to a nominal length of the stent.
31 . The artificial heart valve according to claim 19 , wherein the free part comprises a swelling sub-part and a blood-permeable sub-part which are connected to each other; the swelling sub-part is connected to the closing part; the swelling sub-part swells in the direction away from the stent under the pressure of the backflow blood to abut against the surrounding tissues and achieve sealing; the blood-permeable sub-part allows blood to permeate through; and an axial length of the blood-permeable sub-part is greater than 0 and less than or equal to 40% of a nominal length of the stent.
32 . The artificial heart valve according to claim 31 , wherein the blood-permeable sub-part is made from a blood-permeable material, and/or the blood-permeable sub-part is provided with an opening for allowing blood to permeate through.
33 . The artificial heart valve according to claim 19 , wherein the outer skirt is made from at least one of a biocompatible polymer film, a natural biological tissue, or a surface-modified biocompatible material.
34 . The artificial heart valve according to claim 19 , wherein a spread shape of the outer skirt includes at least one of a triangle, a rectangle, a polygon, a semicircle, a semi-ellipse, or a sector.
35 . The artificial heart valve according to claim 20 , wherein A1≤B1, and the backflow blood permeates through at least a portion of the inner skirt located between the inflow edge and the outflow skirt edge; or A1>B1, and the backflow blood permeates through at least a portion of the inner skirt located between the closing part and the outflow skirt edge.
36 . The artificial heart valve according to claim 20 , wherein C1 is greater than 0 and less than or equal to 40% of a nominal length of the stent

Description

TECHNICAL FIELD The embodiments belong to the field of medical devices, and to an artificial heart valve. BACKGROUND A heart valve is a one-way valve between an atrium and a ventricle or between a ventricle and an artery. A valvular heart disease is one of the most common cardiovascular diseases. In clinical practice, a single valve structure/multiple valve structures abnormalities caused by rheumatic inflammation, degenerative changes, congenital malformations, ischemic necrosis, trauma, and the like may lead to valvular stenosis or valvular inadequacy. For patients suffering from mild valvular heart diseases, the symptom can be relieved through medication. For patients suffering from severe valvular heart diseases, they need valve repair. If valve repair is not feasible, patients need artificial heart valve replacement. Due to factors such as calcification of a native valve, vegetations in the native valve, or defects in the native valve, there may be a gap between an artificial heart valve and the native valve after the artificial heart valve replacement. Blood may leak out from the gap between the artificial heart valve and the native valve under a pressure, forming perivalvular leakage. Worsened perivalvular leakage can lead to symptoms such as chest tightness, chest pain, fatigue, and dizziness. Severe perivalvular leakage can lead to consequences such as heart failure and sudden cardiac death. At present, there have been some methods for preventing perivalvular leakage. For example, an outer skirt with a fibrous edge is added outside an artificial heart valve. The outer skirt promotes blood coagulation in a perivalvular gap, thereby filling a gap between the artificial heart valve and a native valve to achieve the goal of reducing or eliminating perivalvular leakage. However, this method can usually only block small gaps, but has a non-ideal blocking effect on large gaps or notches. For example, there are also methods that use an elastic filling material around an artificial heart valve. A gap between the artificial heart valve and surrounding tissues is reduced by compression and swelling of the filling material, to achieve the goal of reducing and preventing perivalvular leakage. However, a deformation degree of the elastic filling material is limited, so that the blocking effect on large gaps or notches is usually not ideal. It can further easily lead to a further expansion of surrounding tissues, causing damage to the surrounding tissues. SUMMARY To overcome the defects and shortcomings in the existing technology, the embodiments provide an artificial heart valve. An outer skirt of the artificial heart valve can accommodate backflow blood. The blood flows into a free part of the outer skirt from a surface of a leaflet assembly close to the stent via stent holes. Due to non-uniform stress, the blood can flow towards a gap or a notch between surrounding tissues and the stent of the artificial heart valve. Consequently, the free part of the outer skirt can adaptively fill the gap or notch between the surrounding tissues and the stent under the pressure of internal blood, thereby achieving a seal and preventing perivalvular leakage. Meanwhile, as the free part deforms under the pressure of the blood to fill the gap or the notch, the free part does not excessively expand the surrounding tissues, thereby minimizing damage to the surrounding tissues. The artificial heart valve provided by the embodiments includes: a stent, including an inflow end and an outflow end, where a plurality of stent holes are formed in the stent;a leaflet assembly, arranged in the stent, where the leaflet assembly has an inflow edge facing the outflow end;an inner skirt, arranged on an inner surface of the stent, where the inner skirt includes an inflow skirt edge close to the inflow end and an outflow skirt edge close to the outflow end, and the inner skirt is connected to the inflow edge; andan outer skirt, at least partially arranged at an outer periphery of the stent, where the outer skirt includes a closing part, a free part, and a connecting part; the closing part is arranged outside the stent and is close to the inflow end; the closing part is connected to the inner skirt; the free part is connected to the closing part and extends in a direction away from the inflow end; the connecting part is connected to a portion of the free part close to the outflow end, and the connecting part is connected to the stent and/or the inner skirt; backflow blood flows through the stent holes located between the outflow end and the inflow edge and flows into the free part; the free part swells in a direction away from the stent under pressure of the backflow blood to abut against surrounding tissues and achieve sealing. Details of one or more embodiments are set forth in the following drawings and description. Other features, objects, and advantages of the embodiments will become apparent from the drawings and descriptions thereof. BRIEF