JPH0654868A - Artificial valve for living body - Google Patents
Artificial valve for living bodyInfo
- Publication number
- JPH0654868A JPH0654868A JP21052892A JP21052892A JPH0654868A JP H0654868 A JPH0654868 A JP H0654868A JP 21052892 A JP21052892 A JP 21052892A JP 21052892 A JP21052892 A JP 21052892A JP H0654868 A JPH0654868 A JP H0654868A
- Authority
- JP
- Japan
- Prior art keywords
- valve
- leaflet
- curvature
- leaflets
- valve opening
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は心臓弁等に適用できる生
体用人工弁に関し、特に、弁口の中央域を通る主流の他
に弁口の周縁を通る副流も得られる方式の生体用人工弁
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bioprosthetic valve applicable to a heart valve and the like, and more particularly to a bioprosthetic valve which can obtain a main flow passing through the central region of the valve opening as well as a side flow passing through the peripheral edge of the valve opening. Regarding artificial valve.
【0002】[0002]
【従来の技術】従来からの生体用人工弁は未だ、血栓
症、長期使用下における破損等の問題を抱えている。そ
のため、生体の自然弁に近い特性をもつ生体用人工弁が
切望されている。かかる生体用人工弁として、本発明者
等により、円形状の弁口をもつほぼリング状の弁ハウジ
ングと、揺動可能な2個1組の弁葉とをもち、弁葉を揺
動させて弁口の中央域を開弁する中心開放型のものが開
発されている(特開昭63−234965号公報)。こ
のものでは、弁口の中央域を弁葉で開弁するので、生体
の自然弁に近似した血流中心流れが得られ、血栓防止に
有利である。2. Description of the Related Art Conventional artificial valves for living bodies still have problems such as thrombosis and damage during long-term use. Therefore, an artificial valve for a living body having characteristics close to those of the natural valve of the living body is desired. As such an artificial valve for a living body, the present inventors have a substantially ring-shaped valve housing having a circular valve opening, and a set of two rockable leaflets, and swing the leaflets. A center open type has been developed that opens the central region of the valve opening (Japanese Patent Laid-Open No. 63-234965). In this case, since the central region of the valve opening is opened by the leaflets, a central blood flow similar to that of the natural valve of the living body can be obtained, which is advantageous in preventing thrombus.
【0003】更に、従来より、生体用人工弁として、弁
葉を揺動可能に枢支する軸部を弁ハウジングに対して枢
支運動の他に並進運動させ、軸部付近における血栓の防
止を図ったものも知られている(特開昭56−1610
47号公報)。Further, conventionally, as an artificial valve for a living body, a shaft portion that pivotally supports a valve leaf is translated with respect to a valve housing in addition to the pivotal movement to prevent thrombus near the shaft portion. The one designed is also known (JP-A-56-1610).
47 publication).
【0004】[0004]
【発明が解決しようとする課題】更に、本発明者等は、
生体の自然弁に一層近い生体用人工弁として、弁口の中
央域を開弁して血流の主流を得る他に、弁口の周縁をも
開弁して血流の副流を得る方式の人工弁の開発を進めて
いる。この生体用人工弁では、弁葉の中間部が軸部によ
り弁ハウジングに揺動自在に枢支されている。ここで、
弁葉が遠心方向へ揺動すると、各弁葉の前縁が互いに離
遠して弁口の中央域を開弁するとともに、各弁葉の後縁
が弁口の周縁から離遠して開弁する。このものでは、弁
口の中央域を通る主流の他に、弁口の周縁を通る副流が
得られるので、副流による効果的なウオッシュアウト効
果が得られ、弁まわりでの渦、淀みを効果的に回避で
き、血栓防止性を一層向上させ得る。Further, the present inventors have
As a biological artificial valve that is closer to the natural valve of the living body, in addition to opening the central area of the valve opening to obtain the main flow of blood flow, the peripheral edge of the valve opening is also opened to obtain a secondary flow of blood flow. We are developing the artificial valve. In this bioprosthetic valve, the intermediate portion of the leaflet is pivotally supported by the valve housing by the shaft portion. here,
When the leaflets oscillate in the centrifugal direction, the leading edges of the leaflets move away from each other to open the central region of the valve opening, and the trailing edges of the leaflets move away from the peripheral edge of the valve opening. Speak. With this type, in addition to the main flow passing through the central region of the valve opening, a side flow passing through the peripheral edge of the valve opening is obtained, so an effective washout effect due to the side flow is obtained, and vortices and stagnation around the valve are obtained. It can be effectively avoided, and the antithrombogenicity can be further improved.
【0005】本発明は、上記した弁口の中央域を通る主
流の他に弁口の周縁を通る副流が得られる方式の生体用
人工弁を更に技術的に進めたものであり、流体力学的特
性に優れ、特に弁前後の圧力差を小さくし得、弁下流で
の乱流化を一層抑制できる特性をもつ生体用人工弁を提
供することを目的とする。The present invention is a further technical advancement of a bioprosthetic valve of the type in which a side flow passing through the periphery of the valve opening is obtained in addition to the main flow passing through the central area of the valve opening described above. It is an object of the present invention to provide an artificial valve for a living body, which has excellent dynamic characteristics, in particular, can reduce the pressure difference before and after the valve, and can further suppress turbulent flow downstream of the valve.
【0006】[0006]
【課題を解決するための手段】本発明者は、揺動に伴い
開閉する機械式の人工弁における軸部の位置、曲率等が
その弁機能に大きな影響を与えるものと推察し、研究を
進め、本発明を完成させた。すなわち、本発明の生体用
人工弁は、弁口をもつほぼリング状の弁ハウジングと、
互いに対向する前縁と互いに背向し弁口の周縁に沿う弧
状の後縁とをもつ2個1組で構成され、遠心方向及び求
心方向に揺動自在に中間部が軸部により弁ハウジングに
枢支され、遠心方向への揺動に伴い各前縁が離遠して弁
口の中央域を開弁するとともに各後縁が弁口の周縁から
離遠して開弁し、求心方向への揺動に伴い各前縁が近接
して弁口の中央域を閉弁するとともに各後縁が弁口の周
縁に近接して閉弁する弁葉と、弁ハウジング及び弁葉の
少なくとも一方に設けられ、閉弁時において弁口の軸芯
と直交する仮想線に対して各弁葉を傾斜させるストッパ
部とで構成され、弁葉の前縁と後縁とを結ぶ方向におけ
る閉弁時の断面で、弁葉の前縁と軸部の中心とを仮想線
と平行な方向に結ぶ距離をL1とし、仮想線と平行な方
向における弁葉の前縁と後縁とを結ぶ距離をL0とし、
弁葉の翼弦長をC0とし、弁葉の最大キャンパーをC1
とし、弁葉の軸位置(%)=(L1/L0)×100と
し、弁葉の曲率(%)=(C1/C0)×100とした
とき、弁葉の軸位置は67〜73%に設定され、弁葉の
曲率は8〜10%に設定されていることを特徴とするも
のである。Means for Solving the Problems The present inventor speculates that the position, curvature, etc. of the shaft portion of a mechanical artificial valve that opens and closes in response to swinging greatly influences the valve function, and advances the research. The present invention has been completed. That is, the bioprosthetic valve of the present invention is a substantially ring-shaped valve housing having a valve opening,
It is composed of a pair of two having front edges facing each other and arcuate rear edges facing back to each other and extending along the peripheral edge of the valve opening. The intermediate part is pivotally movable in the centrifugal direction and the centripetal direction by the shaft part to the valve housing. It is pivotally supported, and as it swings in the centrifugal direction, each leading edge separates and opens the central region of the valve opening, and each trailing edge separates from the peripheral edge of the valve opening and opens, and in the centripetal direction. The leading edge of each valve closes to close the central region of the valve opening and the trailing edge of each valve closes to the edge of the valve opening, and at least one of the valve housing and the valve leaf. When the valve is closed, it is configured with a stopper portion that tilts each leaflet with respect to an imaginary line that is orthogonal to the axis of the valve opening when the valve is closed. In the cross section, the distance connecting the front edge of the leaflets and the center of the shaft portion in the direction parallel to the imaginary line is L1, and the leaflet in the direction parallel to the imaginary line is L1. The distance connecting the leading and trailing edges and L0,
Let the chord length of the leaflets be C0, and let the maximum camber of the leaflets be C1.
And the axial position of the leaflet (%) = (L1 / L0) × 100 and the curvature of the leaflet (%) = (C1 / C0) × 100, the axial position of the leaflet is 67 to 73%. The curvature of the leaflets is set to 8 to 10%.
【0007】本発明では、弁葉と軸部とは別体であって
も、一体であっても良い。In the present invention, the leaflet and the shaft portion may be separate bodies or one body.
【0008】[0008]
【作用】本発明の生体用人工弁では、開弁時には、弁口
の中央域を通る主流が得られる他に、弁口の周縁を通る
副流が得られる。本発明の生体用人工弁では、弁葉の軸
位置は67〜73%に設定され、弁葉の曲率は8〜10
%に設定されているので、流体力学的特性が向上する。In the artificial valve for a living body of the present invention, when the valve is opened, a main flow passing through the central region of the valve opening is obtained, and a side flow passing through the peripheral edge of the valve opening is obtained. In the bioprosthetic valve of the present invention, the axial position of the leaflet is set to 67 to 73%, and the curvature of the leaflet is 8 to 10%.
%, The hydrodynamic characteristics are improved.
【0009】[0009]
【実施例】本発明の生体用人工弁に係る実施例を図面を
参照して説明する。図1及び図2は閉弁状態を示す。図
3は弁ハウジング1を示す。図1、図3に示す様に弁ハ
ウジング1は、弁口10をもつほぼリング状をなす。弁
口10は弧面10a、弧面10b、直状面10e、直状
面10fで区画されている。弁ハウジング1の取付孔1
aにはストッパ部11が挿入され、ストッパ部11は弁
ハウジング1の孔1bに螺合された止め螺子12で固定
されている。なお、弁ハウジング1、ストッパ部11、
止め螺子12はステンレス製であり、抗血栓性が期待さ
れる所要厚みの窒化チタンの膜が積層されている。Embodiments of the artificial valve for a living body of the present invention will be described with reference to the drawings. 1 and 2 show the valve closed state. FIG. 3 shows the valve housing 1. As shown in FIGS. 1 and 3, the valve housing 1 has a substantially ring shape having a valve port 10. The valve port 10 is divided into an arc surface 10a, an arc surface 10b, a straight surface 10e, and a straight surface 10f. Mounting hole 1 for valve housing 1
A stopper portion 11 is inserted in a, and the stopper portion 11 is fixed by a set screw 12 screwed into the hole 1b of the valve housing 1. In addition, the valve housing 1, the stopper portion 11,
The set screw 12 is made of stainless steel, and a titanium nitride film having a required thickness, which is expected to have antithrombogenicity, is laminated.
【0010】図1、図2に示す様に、弁葉2は2個1組
で構成されている。弁葉2は、互いに対向する前縁2a
と、互いに背向し弁口10の周縁10iの弧面10aに
沿う形状の後縁2bとをもち、更に側面縁2e、2f、
弧縁面2iとをもつ。さらに図1、図6に示す様に、弁
葉2の中間部としての側面縁2fに形成された孔2wに
はステンレス製の軸部20(外径0.5mm)が挿入さ
れている。As shown in FIGS. 1 and 2, the leaflets 2 are composed of two pairs. The leaflets 2 have front edges 2a facing each other.
And a rear edge 2b having shapes that face each other and extend along the arc surface 10a of the peripheral edge 10i of the valve opening 10, and further include side surface edges 2e, 2f,
It has an arc edge surface 2i. Further, as shown in FIGS. 1 and 6, a stainless shaft 20 (outer diameter 0.5 mm) is inserted into a hole 2w formed in the side edge 2f as an intermediate portion of the leaflet 2.
【0011】なお、図6において、後縁2bは弧中心M
1から半径r1で形成されており、弧縁面2iは弧中心
M1から半径r2で形成されている。また図7におい
て、弁葉2の内面2n、外面2kは外方へ若干膨出して
いる。又、図8において、弁葉2の外面2kは弧中心M
2から半径r4で形成されており、弁葉2の内面2nは
弧中心M3から半径r5で形成されている。In FIG. 6, the trailing edge 2b has an arc center M.
The arc edge surface 2i is formed from the arc center M1 to the radius r2. Further, in FIG. 7, the inner surface 2n and the outer surface 2k of the valve leaf 2 are slightly bulged outward. Further, in FIG. 8, the outer surface 2k of the leaflet 2 has an arc center M.
The inner surface 2n of the leaflet 2 is formed from the arc center M3 to the radius r5.
【0012】図4、図5に示す様に前記したストッパ部
11は、テーパ状のストッパ面11a、11bと、挿入
孔11d(内径0.5mm)とをもつ。そして、図5に
示す様に、軸部20がストッパ部11の挿入孔11dに
挿入されて、各弁葉2は軸部20により弁ハウジング1
に枢支され、これにより各弁葉2は遠心方向つまり矢印
A1方向及び求心方向つまり矢印A2方向に揺動可能と
されている。本実施例では、図5から理解できる様に、
弁葉2とストッパ面11a、11bの境界域11cとの
間には隙間14(0.1mm程度)が形成されているの
で、軸部20のまわりにおいて血流(図5における矢印
S方向の血流)によるウオッシュアウト効果が得られ、
軸部20のまわり、ストッパ部11のまわりにおける血
栓防止に有利である。As shown in FIGS. 4 and 5, the stopper portion 11 has tapered stopper surfaces 11a and 11b and an insertion hole 11d (inner diameter 0.5 mm). Then, as shown in FIG. 5, the shaft portion 20 is inserted into the insertion hole 11 d of the stopper portion 11, so that each valve leaf 2 is moved by the shaft portion 20.
The valve leaflets 2 are swingable in the centrifugal direction, that is, the arrow A1 direction and in the centripetal direction, that is, the arrow A2 direction. In this embodiment, as can be understood from FIG.
Since a gap 14 (about 0.1 mm) is formed between the leaflet 2 and the boundary region 11c of the stopper surfaces 11a and 11b, blood flow (blood in the direction of arrow S in FIG. 5) around the shaft portion 20. )) Washout effect,
This is advantageous for preventing thrombus around the shaft portion 20 and around the stopper portion 11.
【0013】ここで、図2から理解できるように、弁葉
2の遠心方向つまり矢印A1方向への揺動に伴い、各弁
葉2の前縁2aが互いに離遠して弁口10の中央域10
hを開弁するとともに、各弁葉2の後縁2bが弁口10
の周縁10iの弧面10aから離遠して開弁する。ま
た、弁葉2の求心方向つまり矢印A2方向への揺動に伴
い、各弁葉2の前縁2aが互いに近接して弁口10の中
央域10hを閉弁するとともに、各弁葉2の後縁2bが
弁口10の周縁10iの弧面10aに近接して閉弁す
る。なお、図2において矢印Wは血流の流れる方向を示
し、よってW1は上流、W2は下流を示す。Here, as can be understood from FIG. 2, as the leaflets 2 swing in the centrifugal direction, that is, in the direction of arrow A1, the front edges 2a of the leaflets 2 move away from each other and the center of the valve opening 10 is separated. Area 10
h is opened, and the trailing edge 2b of each leaflet 2 is opened at the valve opening 10
The valve is opened apart from the arc surface 10a of the peripheral edge 10i. Further, as the leaflets 2 swing in the centripetal direction, that is, in the direction of the arrow A2, the leading edges 2a of the leaflets 2 approach each other to close the central region 10h of the leaflets 10, and The trailing edge 2b closes the arc surface 10a of the peripheral edge 10i of the valve opening 10 to close the valve. In FIG. 2, the arrow W indicates the direction of blood flow, and therefore W1 indicates upstream and W2 indicates downstream.
【0014】さて図9は、閉弁状態において弁葉2の前
縁2aと後縁2bとを結ぶ方向における中央断面を示
す。ここで、前縁2aは、弁葉2の先端と弁葉2の肉厚
中の肉厚中心線Eとの交点を意味する。図9において、
弁葉2の前縁2aと軸部20の中心とを仮想線P2と平
行な方向に結ぶ距離をL1とし、仮想線P2と平行な方
向における弁葉2の前縁2aと後縁2bとを結ぶ距離を
L0とする。更に、弁葉2の翼弦長をC0とし、弁葉2
の最大キャンパーをC1とする。ここで、図9から理解
できる様に、弁葉2の翼弦長COは、弁葉2の肉厚中心
線Eの始点E1と終点E2(前縁2a)とを結ぶ最短距
離を意味する。また、弁葉2の最大キャンパーC1は、
弁葉2の肉厚中心線Eの始点E1と終点E2とを結ぶ直
線Fと、肉厚中心線Eの最大曲率点E3との最短距離を
意味する。Now, FIG. 9 shows a central cross section in the direction connecting the front edge 2a and the rear edge 2b of the leaf 2 in the valve closed state. Here, the front edge 2a means the intersection of the tip of the leaflet 2 and the thickness center line E in the thickness of the leaflet 2. In FIG.
The distance connecting the front edge 2a of the leaflet 2 and the center of the shaft portion 20 in the direction parallel to the imaginary line P2 is L1, and the front edge 2a and the rear edge 2b of the leaflet 2 in the direction parallel to the imaginary line P2 are The connecting distance is L0. Further, the chord length of the leaflets 2 is set to C0, and the leaflets 2
The maximum camper of C1 is C1. Here, as can be understood from FIG. 9, the chord length CO of the leaflet 2 means the shortest distance connecting the start point E1 and the end point E2 (front edge 2a) of the thickness centerline E of the leaflet 2. Also, the maximum camper C1 of the leaflets 2 is
It means the shortest distance between the straight line F connecting the starting point E1 and the end point E2 of the thickness center line E of the leaflet 2 and the maximum curvature point E3 of the thickness center line E.
【0015】ここで、弁葉2の軸位置(%)=(L1/
L0)×100とし、弁葉2の曲率(%)=(C1/C
0)×100とする。本実施例では、弁葉2の軸位置は
約70%に設定され、弁葉2の曲率は約9%に設定され
ている。なお、図5から理解できる様に、閉弁時におい
ては、矢印A2方向に揺動した弁葉2がストッパ部11
のストッパ面11aに規制される。この様な閉弁時にお
いては、図2に示す様に、弁葉2は弁口10の軸芯P1
と直交する仮想線P2に対して角度θ2(15°)傾斜
して保持される。これは、弁葉2の開閉応答を迅速に行
うためである。また図5から理解できる様に、開弁時に
おいては、弁葉2がストッパ部11のストッパ面11b
に規制される。弁葉2が全開したときにおいて、前記し
た仮想線P2に対する弁葉2の弁全開時の角度は62°
である。ここで、基本的には、弁葉2の全開時には、弁
葉2の肉厚中心線Eの始点E1から肉厚中心線Eに引い
た接線が90°となるように設計されている。Here, the axial position (%) of the leaflets 2 = (L1 /
L0) × 100, and curvature (%) of leaflet 2 = (C1 / C
0) × 100. In this embodiment, the axial position of the leaf 2 is set to about 70%, and the curvature of the leaf 2 is set to about 9%. As can be understood from FIG. 5, when the valve is closed, the valve leaf 2 oscillated in the direction of the arrow A2 is moved to the stopper portion 11
Is regulated by the stopper surface 11a. At the time of such valve closing, as shown in FIG. 2, the valve leaf 2 has the axis P1 of the valve port 10.
It is held at an angle θ2 (15 °) with respect to an imaginary line P2 that is orthogonal to. This is because the opening / closing response of the leaflets 2 is performed quickly. Further, as can be understood from FIG. 5, when the valve is opened, the valve leaf 2 has the stopper surface 11b of the stopper portion 11.
Regulated by. When the leaflet 2 is fully opened, the angle of the leaflet 2 with respect to the imaginary line P2 when the valve is fully opened is 62 °.
Is. Here, basically, when the leaflet 2 is fully opened, the tangent line drawn from the starting point E1 of the thickness centerline E of the leaflet 2 to the thickness centerline E is 90 °.
【0016】本実施例では、弁葉2はA1−Zn−Mg
系のアルミニウム基金属つまり超々ジュラルミン(JI
S A7056−T6)で形成され、その表面には反応
性スパッタリングにより酸化アルミニウムの膜が積層さ
れている。酸化アルミニウムの膜はその最表面側が高濃
度となる様な傾斜組成とされている。酸化アルミニウム
は生体適合性、血液適合性をもつ。この酸化アルミニウ
ムは構造的にはアモルファス構造であり、組成的には酸
素リッチであることが確認された。また本実施例では、
弁葉2はA1−Zn−Mg系のアルミニウム基金属で形
成されているので、耐久性、強度を確保しつつ、良好な
切削加工性をもち、弁葉の形状設定に有利である。本実
施例では、成膜手段として反応性スパッタリングを利用
したことで、低温での成膜が可能となり、弁葉2を構成
するアルミニウム基金属の機械的特性の熱劣化を防止で
きる。In this embodiment, the leaflets 2 are A1-Zn-Mg.
Aluminum-based metals of the series, namely ultra-super duralumin (JI
S A7056-T6), and a film of aluminum oxide is laminated on the surface thereof by reactive sputtering. The aluminum oxide film has a graded composition so that the outermost surface thereof has a high concentration. Aluminum oxide is biocompatible and blood compatible. It was confirmed that the aluminum oxide had an amorphous structure structurally and was oxygen-rich compositionally. Further, in this embodiment,
Since the leaflets 2 are formed of an Al1-Zn-Mg-based aluminum-based metal, they have good machinability while ensuring durability and strength, and are advantageous in setting the shape of the leaflets. In this embodiment, since reactive sputtering is used as the film forming means, it is possible to form a film at a low temperature, and it is possible to prevent thermal deterioration of the mechanical properties of the aluminum-based metal forming the leaflets 2.
【0017】以上説明した様に本実施例では、弁葉2の
開弁時には、弁口10の中央域10hの他に弁口10の
周縁10iも開弁されるので、弁口10の中央域10h
を通る主流の他に、弁口10の周縁10iを通る副流が
得られ、弁まわりでの渦、淀みを効果的に回避でき、優
れた血栓防止効果が得られる。更に本実施例では、弁葉
2の軸位置は約70%に設定され、弁葉2の曲率は約9
%に設定されているので、後述の試験例に示す様に、流
体力学的特性が向上した弁葉2が得られ、人の自然弁に
一層近似したものが得られる。As described above, in the present embodiment, when the valve leaf 2 is opened, the peripheral area 10i of the valve opening 10 is opened in addition to the central area 10h of the valve opening 10, so that the central area of the valve opening 10 is opened. 10h
In addition to the main flow passing through, the secondary flow passing through the peripheral edge 10i of the valve opening 10 can be obtained, vortices and stagnation around the valve can be effectively avoided, and an excellent thrombus prevention effect can be obtained. Further, in this embodiment, the axial position of the leaf 2 is set to about 70%, and the curvature of the leaf 2 is about 9%.
%, The leaflets 2 having improved hydrodynamic characteristics can be obtained, as shown in the test example described later, and a leaflet more similar to a human natural valve can be obtained.
【0018】(試験例)弁葉2の軸位置および弁葉2の
曲率をパラメ−タとして表1に示す7種類の人工弁を試
作した。即ち、弁葉2の軸位置を70%に固定して弁葉
2の曲率を0%、9%、11%、13%と変化させたも
のと、弁葉2の曲率を9%に固定して軸位置を65%、
70%、75%、80%と変化させたものの計7種類を
試作した。そして表1に示す様に、各人工弁はS650
9、S7000、S7009、S7011、S701
3、S7509、S8009で表した。ここで、例えば
人工弁S7009において、70の数字は軸位置を示
し、09の数字は曲率を示す。(Test Example) Seven kinds of artificial valves shown in Table 1 were made as trials by using the axial position of the leaflets 2 and the curvature of the leaflets 2 as parameters. That is, the axial position of the leaflets 2 was fixed at 70% and the curvature of the leaflets 2 was changed to 0%, 9%, 11% and 13%, and the curvature of the leaflets 2 was fixed at 9%. Axis position 65%,
Seven types of prototypes were produced, with the changes being 70%, 75%, and 80%. And, as shown in Table 1, each artificial valve is S650.
9, S7000, S7009, S7011, S701
3, S7509 and S8009. Here, for example, in the artificial valve S7009, the numeral 70 indicates the axial position and the numeral 09 indicates the curvature.
【0019】[0019]
【表1】 (1)試験方法 試作した各人工弁を用い、流体力学的な特性評価を行っ
た。この場合、以下述べる様な定常流試験、定圧もれ試
験、生体内の左心系体循環を模擬した拍動流試験を行っ
た。 (1−1)定常流試験 基礎的な流体特性評価として、定常流における弁前後の
圧力差および流れの可視化による弁通過後の流体動態を
試験した。この試験は、長さ250cmのアクリル管の
先に人工弁を固定し、一定の静圧を保ったタンクからバ
ルブによって流量を0.5〜14.0L/minに変化
させて行った。また、アクリル管に流す流体として、血
液の比重(1.08)、血液の粘度(2.7cSt)に
適応する様に、34%グリセリン水溶液を用いた。ま
た、流れの可視化には、トレーサーとしてアルミニウム
粉末を用いた。 (1−2)拍動流試験 この試験では、生体内の左心系体循環を模擬した、拍動
流における流体力学的な弁機能評価を行った。この試験
は、駆動圧(150mmHg)、動脈コンプライアンス
(0.015L/mmHg)、末梢抵抗(16.25m
mHg min/L)および心臓収縮期(0.29s)
を一定とし、拍動数を1分間あたり60、72、84、
96回と変化させて行なった。[Table 1] (1) Test method Using each prototype artificial valve, hydrodynamic characteristic evaluation was performed. In this case, a steady flow test, a constant pressure leak test, and a pulsatile flow test simulating the left ventricular system circulation in vivo were performed as described below. (1-1) Steady flow test As a basic fluid property evaluation, the fluid dynamics after passing through the valve were tested by visualizing the pressure difference before and after the valve in the steady flow. This test was performed by fixing an artificial valve to the tip of an acrylic tube having a length of 250 cm, and changing the flow rate from 0.5 to 14.0 L / min by a valve from a tank maintaining a constant static pressure. A 34% glycerin aqueous solution was used as a fluid to flow through the acrylic tube so as to adapt to the specific gravity of blood (1.08) and the viscosity of blood (2.7 cSt). In addition, aluminum powder was used as a tracer for visualization of the flow. (1-2) Pulsatile flow test In this test, a hydrodynamic valve function evaluation in pulsatile flow, which simulates the left ventricular system circulation in the living body, was performed. This test is based on driving pressure (150 mmHg), arterial compliance (0.015 L / mmHg), peripheral resistance (16.25 m).
mHg min / L) and systole (0.29s)
Is constant and the number of beats is 60, 72, 84 per minute,
The number of times was changed to 96 times.
【0020】そして、流量、有効弁口面積、エネルギ損
失、および弁閉鎖流量(弁閉鎖時の逆流量)を測定し
た。なお、有効弁口面積の算出にはGorlinの式を
用いた。 (1−3)定圧もれ試験 弁閉鎖時におけるもれ量の評価として、定圧もれ試験を
行なった。試験は、人工弁(S7009)を用いて一定
圧(100cmH2O)でのもれ量を測定し、1分間あたりの量に
換算した。Then, the flow rate, the effective valve opening area, the energy loss, and the valve closing flow rate (reverse flow rate when the valve was closed) were measured. The Gorlin equation was used to calculate the effective valve opening area. (1-3) Constant Pressure Leakage Test A constant pressure leakage test was performed as an evaluation of the amount of leakage when the valve was closed. In the test, the amount of leak at a constant pressure (100 cmH 2 O) was measured using an artificial valve (S7009) and converted into the amount per minute.
【0021】(2)試験結果 (2−1)定常流試験の結果 図10、図11に定常流を用いた場合における人工弁前
後の圧力差の試験結果を示す。図10は、軸位置による
比較である。図10の結果より、S6509(軸位置6
5%、曲率9%)を除いては、特に大きな変化は見られ
ない。よって表2のA欄に示す様に軸位置65%は×と
判定し、軸位置70%、75%、80%は○と判定し
た。(2) Test Results (2-1) Results of Steady Flow Test FIGS. 10 and 11 show the test results of the pressure difference before and after the artificial valve when the steady flow is used. FIG. 10 is a comparison according to the axial position. From the result of FIG. 10, S6509 (axial position 6
Except for 5% and curvature 9%), no significant change is observed. Therefore, as shown in the column A of Table 2, the axial position 65% was determined as x, and the axial positions 70%, 75%, and 80% were determined as o.
【0022】図11は、弁葉2の曲率による比較であ
る。図11の結果より、弁葉2の曲率が人工弁の前後の
圧力差に大きく影響することが観察された。特に、S7
009(軸位置70%、曲率9%)が圧力差が最も小さ
いことが観察された。圧力差が大きいと、弁下流で乱流
に移行し易くなり、好ましくない。よって表3のA欄に
示す様に曲率0%、9%は○と判定し、曲率13%は×
と判定した。FIG. 11 is a comparison based on the curvature of the leaflets 2. From the result of FIG. 11, it was observed that the curvature of the leaflets 2 greatly affects the pressure difference before and after the artificial valve. In particular, S7
It was observed that 009 (axial position 70%, curvature 9%) had the smallest pressure difference. If the pressure difference is large, turbulent flow is likely to occur downstream of the valve, which is not preferable. Therefore, as shown in the column A of Table 3, 0% and 9% of curvatures are judged as ◯, and 13% of curvatures are ×.
It was determined.
【0023】[0023]
【表2】 [Table 2]
【0024】[0024]
【表3】 定常流における人工弁の流れの可視化試験では、弁口1
0の中央域10hを通る主流は、弁葉2の軸位置の変動
による影響をあまり受けなかった。しかし副流は、弁葉
2の軸位置の変動の影響を大きく受けた。すなわち、弁
葉2の軸位置の値を大きくすると、副流は小さくなり、
よって、副流による血栓防止効果が低下すると推察され
る。弁周りの淀みを効果的に減少させるためには、S7
009程度の副流の流れが必要である。従って表2のB
欄に示す様に、軸位置70%は○と判定し、表3のB欄
に示す様に曲率9%も○と判定した。 (2−2)拍動流試験の結果 図12、図13に、拍動流を用いた場合における拍出流
量と拍動数との関係を示す。図12は弁葉2の軸位置に
よる比較である。図12においてS7009、S800
9は流量が大きく、S6509は流量が最も小さい。よ
って表2のC欄に示す様に軸位置70%、80%は○と
判定し、軸位置65%、75%は△と判定した。図13
は弁葉2の曲率による比較である。図13において、S
7009は流量が最も大きく、S7013は流量が最も
小さい。よって表3のC欄に示す様に曲率9%は○と判
定し、曲率13%は×と判定し、曲率0%、11%は△
と判定した。[Table 3] In the visualization test of the flow of the artificial valve in the steady flow, the valve opening 1
The main flow passing through the central region 10h of 0 was not significantly affected by the change in the axial position of the leaflets 2. However, the sidestream was greatly affected by the change in the axial position of the leaflets 2. That is, when the value of the axial position of the leaflet 2 is increased, the side flow becomes smaller,
Therefore, it is presumed that the thrombus prevention effect due to the sidestream is reduced. To effectively reduce the stagnation around the valve, S7
A sidestream flow of about 009 is required. Therefore, B in Table 2
As shown in the column, 70% of the axial position was judged as ◯, and as shown in the column B of Table 3, 9% of curvature was also judged as ◯. (2-2) Results of pulsatile flow test FIGS. 12 and 13 show the relationship between the pulsating flow rate and the pulsation rate when pulsatile flow is used. FIG. 12 is a comparison according to the axial position of the leaflets 2. 12, S7009 and S800
9 has a large flow rate, and S6509 has the smallest flow rate. Therefore, as shown in the column C of Table 2, 70% and 80% of the shaft positions were judged to be ◯, and 65% and 75% of the shaft positions were judged to be Δ. FIG.
Is a comparison based on the curvature of the leaflets 2. In FIG. 13, S
7009 has the highest flow rate, and S7013 has the lowest flow rate. Therefore, as shown in the column C of Table 3, 9% of curvature is judged as ◯, 13% of curvature is judged as ×, and 0% and 11% of curvature are Δ.
It was determined.
【0025】図14、図15に、有効弁口面積と拍動数
との関係を示す。図14は弁葉2の軸位置による比較で
ある。図14においてS8009は有効弁口面積が最も
大きく、S6509は有効弁口面積が最も小さい。よっ
て表2のD欄に示す様に軸位置80%は○と判定し、軸
位置65%は×と判定し、軸位置70%、75%は△と
判定した。図15は弁葉2の曲率による比較である。図
15において、S7009は有効弁口面積が最も大き
く、S7000は有効弁口面積が最も小さい。よって表
3のD欄に示す様に曲率9%は○と判定し、曲率0%は
×と判定し、曲率11%、13%は△と判定した。14 and 15 show the relationship between the effective valve opening area and the pulsation rate. FIG. 14 is a comparison according to the axial position of the leaflets 2. In FIG. 14, S8009 has the largest effective valve opening area, and S6509 has the smallest effective valve opening area. Therefore, as shown in column D of Table 2, 80% of the shaft positions were judged as ◯, 65% of the shaft positions were judged as x, and 70% and 75% of the shaft positions were judged as Δ. FIG. 15 is a comparison based on the curvature of the leaflets 2. In FIG. 15, S7009 has the largest effective valve opening area, and S7000 has the smallest effective valve opening area. Therefore, as shown in the column D of Table 3, 9% of curvature was judged as ◯, 0% of curvature was judged as ×, and 11% and 13% of curvature were judged as Δ.
【0026】図16、図17に各人工弁における拍動数
とエネルギ損失との関係を示す。図16は軸位置による
比較である。図16に示す結果より、軸位置の違いによ
ってエネルギ損失には大きな差は見られないが、S80
09はエネルギ損失が最も小さく、S6509はエネル
ギ損失が最も大きい。よって表2のE欄に示す様に軸位
置80%は○と判定し、軸位置65%は×と判定し、軸
位置70%、75%は△と判定した。図17は、弁葉2
の曲率の違いによるエネルギ損失の比較である。図17
に示す様に、S7013で最も大きなエネルギ損失が見
られ、S7009はエネルギ損失が最も小さい。よって
表3のE欄に示す様に曲率13%は×と判定し、曲率9
%は○と判定し、曲率0%、11%は△と判定した。16 and 17 show the relationship between the pulse rate and energy loss in each artificial valve. FIG. 16 is a comparison according to the axial position. From the results shown in FIG. 16, although there is no significant difference in energy loss due to the difference in shaft position, S80
09 has the smallest energy loss, and S6509 has the largest energy loss. Therefore, as shown in the E column of Table 2, 80% of the shaft positions were judged as ◯, 65% of the shaft positions were judged as ×, and 70% and 75% of the shaft positions were judged as Δ. FIG. 17 shows leaflet 2
3 is a comparison of energy loss due to a difference in curvature of the. FIG. 17
As shown in, the largest energy loss is observed in S7013, and the energy loss is smallest in S7009. Therefore, as shown in column E of Table 3, a curvature of 13% is judged as x, and a curvature of 9% is determined.
% Was judged as ◯, curvature 0% and 11% were judged as Δ.
【0027】図18、図19に各人工弁における拍動数
と弁閉鎖流量(弁閉鎖時の逆流量)との関係を示す。図
18は軸位置による比較である。図18に示す結果よ
り、S7009が最も弁閉鎖流量が小さいことがわか
る。よって表2のF欄に示す様に軸位置70%は○と判
定し、軸位置65%、75%、80%は△と判定した。
図19は、弁葉2の曲率による弁閉鎖流量の比較であ
る。図19に示す結果より、S7013、S7009は
弁閉鎖流量が小さく、S7000は弁閉鎖流量が最も大
きい。よって表3のF欄に示す様に曲率13%、9%は
○と判定し、曲率0%は×と判定し、曲率11%は△と
判定した。 (2−3)定圧もれ試験の結果 S7009に係る人工弁の定圧もれ量は、厚生省で定め
たもれ量1.5 L/minの半分以下であった。 (2−4)総合評価 表2においては軸位置70%で○が多く、表3において
は曲率9%で○が多い。従って、定常流および拍動流で
の流体力学的特性評価から、総合的に勘案すると、S7
009(軸位置70%、曲率9%)が、最も適切な形状
であると把握される。特に、図11から理解できる様
に、S7009は、人工弁の前後の圧力差が最も小さい
ので、人工弁の下流側における乱流化を抑制できる効果
が大きい。18 and 19 show the relationship between the pulse rate and the valve closing flow rate (reverse flow rate when the valve is closed) in each artificial valve. FIG. 18 is a comparison according to the axial position. From the results shown in FIG. 18, it can be seen that S7009 has the smallest valve closing flow rate. Therefore, as shown in column F of Table 2, 70% of the shaft positions were judged to be ◯, and 65%, 75% and 80% of the shaft positions were judged to be Δ.
FIG. 19 is a comparison of valve closing flow rates depending on the curvature of the valve leaf 2. From the results shown in FIG. 19, the valve closing flow rate is small in S7013 and S7009, and the valve closing flow rate is the largest in S7000. Therefore, as shown in the column F of Table 3, the curvatures of 13% and 9% were judged as ◯, the curvature of 0% was judged as ×, and the curvature of 11% was judged as Δ. (2-3) Result of constant pressure leakage test The constant pressure leakage amount of the artificial valve according to S7009 was less than half of the leakage amount of 1.5 L / min determined by the Ministry of Health and Welfare. (2-4) Comprehensive Evaluation In Table 2, there are many ◯ when the axial position is 70%, and in Table 3, there are many ◯ when the curvature is 9%. Therefore, when comprehensively considering from the hydrodynamic characteristic evaluations in the steady flow and the pulsatile flow, S7
009 (70% axial position, 9% curvature) is understood to be the most suitable shape. In particular, as can be understood from FIG. 11, in S7009, since the pressure difference before and after the artificial valve is the smallest, the effect of suppressing turbulence on the downstream side of the artificial valve is great.
【0028】[0028]
【発明の効果】本発明によれば、主流の他に副流も得ら
れ、しかも、流体力学的特性に優れ、特に弁前後の圧力
差を小さくし得て弁下流における乱流を抑制できるとい
う優れた特性をもつ生体用人工弁が得られる。According to the present invention, not only the main flow but also the sub-flow can be obtained, and the hydrodynamic characteristics are excellent. In particular, the pressure difference before and after the valve can be made small, and the turbulent flow in the downstream of the valve can be suppressed. A bioprosthetic valve having excellent characteristics can be obtained.
【図面の簡単な説明】[Brief description of drawings]
【図1】本発明の生体用人工弁の平面図である。FIG. 1 is a plan view of a bioprosthetic valve of the present invention.
【図2】本発明の生体用人工弁の図1におけるB−B’
断面図である。FIG. 2 is a sectional view taken along line BB ′ in FIG. 1 of the bioprosthetic valve of the present invention.
FIG.
【図3】本発明の生体用人工弁の弁ハウジングの平面図
である。FIG. 3 is a plan view of the valve housing of the bioprosthetic valve of the present invention.
【図4】図3の矢印Y1方向からみた本発明の生体用人
工弁のストッパ部の正面図である。4 is a front view of the stopper portion of the bioprosthetic valve of the present invention as seen from the direction of arrow Y1 in FIG.
【図5】弁葉を揺動可能に枢支した状態を示す本発明の
生体用人工弁のストッパ部付近の説明図である。FIG. 5 is an explanatory view of the vicinity of the stopper portion of the bioprosthetic valve of the present invention showing a state in which the leaflet is pivotally supported.
【図6】本発明の生体用人工弁の弁葉の平面図である。FIG. 6 is a plan view of the leaflet of the bioprosthetic valve of the present invention.
【図7】図6の矢印Y2方向からみた本発明の生体用人
工弁の弁葉の正面図である。FIG. 7 is a front view of the leaflet of the bioprosthetic valve of the present invention viewed from the direction of arrow Y2 in FIG.
【図8】図6の矢印Y3方向からみた本発明の生体用人
工弁の弁葉の正面図である。8 is a front view of the leaflet of the bioprosthetic valve of the present invention as seen from the direction of the arrow Y3 in FIG.
【図9】L1、L0、C0、C1を示すための本発明の
生体用人工弁の弁葉の説明図である。FIG. 9 is an explanatory diagram of leaflets of the bioprosthetic valve of the present invention for showing L1, L0, C0, and C1.
【図10】軸位置を変更した場合における定常流の流量
と圧力差との関係を示すグラフである。FIG. 10 is a graph showing a relationship between a steady flow rate and a pressure difference when the axial position is changed.
【図11】曲率を変更した場合における定常流の流量と
圧力差との関係を示すグラフである。FIG. 11 is a graph showing the relationship between the flow rate of a steady flow and the pressure difference when the curvature is changed.
【図12】軸位置を変更した場合における拍出流量と拍
動数との関係を示すグラフである。FIG. 12 is a graph showing the relationship between the stroke flow rate and the pulsation rate when the axis position is changed.
【図13】曲率を変更した場合における拍出流量と拍動
数との関係を示すグラフである。FIG. 13 is a graph showing the relationship between the ejection flow rate and the pulsation rate when the curvature is changed.
【図14】軸位置を変更した場合における有効弁口面積
と拍動数との関係を示すグラフである。FIG. 14 is a graph showing the relationship between the effective valve opening area and the pulsation rate when the axial position is changed.
【図15】曲率を変更した場合における有効弁口面積と
拍動数との関係を示すグラフである。FIG. 15 is a graph showing the relationship between the effective valve opening area and the pulsation rate when the curvature is changed.
【図16】軸位置を変更した場合におけるエネルギ損失
と拍動数との関係を示すグラフである。FIG. 16 is a graph showing the relationship between energy loss and pulse rate when the axis position is changed.
【図17】曲率を変更した場合におけるエネルギ損失と
拍動数との関係を示すグラフである。FIG. 17 is a graph showing the relationship between energy loss and pulse rate when the curvature is changed.
【図18】軸位置を変更した場合における弁閉鎖流量と
拍動数との関係を示すグラフである。FIG. 18 is a graph showing the relationship between the valve closing flow rate and the pulsation rate when the axial position is changed.
【図19】曲率を変更した場合における弁閉鎖流量と拍
動数との関係を示すグラフである。FIG. 19 is a graph showing the relationship between the valve closing flow rate and the pulsation rate when the curvature is changed.
図中、1は弁ハウジング、10は弁口、11はストッパ
部、11aはストッパ面、2は弁葉、2aは前縁、2b
は後縁、P2は仮想線を示す。In the figure, 1 is a valve housing, 10 is a valve opening, 11 is a stopper portion, 11a is a stopper surface, 2 is a valve leaf, 2a is a front edge, and 2b.
Indicates a trailing edge, and P2 indicates an imaginary line.
Claims (1)
と、 互いに対向する前縁と互いに背向し該弁口の周縁に沿う
弧状の後縁とをもつ2個1組で構成され、遠心方向及び
求心方向に揺動自在に中間部が軸部により該弁ハウジン
グに枢支され、遠心方向への揺動に伴い各前縁が離遠し
て該弁口の中央域を開弁するとともに各後縁が該弁口の
周縁から離遠して開弁し、求心方向への揺動に伴い各前
縁が近接して該弁口の中央域を閉弁するとともに各後縁
が該弁口の周縁に近接して閉弁する弁葉と、 該弁ハウジング及び該弁葉の少なくとも一方に設けら
れ、閉弁時において該弁口の軸芯と直交する仮想線に対
して各該弁葉を傾斜させるストッパ部とで構成され、 該弁葉の前縁と後縁とを結ぶ方向における閉弁時の断面
で、該弁葉の前縁と軸部の中心とを該仮想線と平行な方
向に結ぶ距離をL1とし、該仮想線と平行な方向におけ
る該弁葉の前縁と後縁とを結ぶ距離をL0とし、該弁葉
の翼弦長をC0とし、該弁葉の最大キャンパーをC1と
し、該弁葉の軸位置(%)=(L1/L0)×100と
し、該弁葉の曲率(%)=(C1/C0)×100とし
たとき、 該弁葉の軸位置は67〜73%に設定され、該弁葉の曲
率は8〜10%に設定されていることを特徴とする生体
用人工弁。1. A centrifuge, comprising a pair of valve housings each having a substantially ring-shaped valve housing having a valve opening, front edges facing each other, and arc-shaped rear edges facing each other and extending along the periphery of the valve opening. The central portion is pivotally supported by the valve housing by the shaft portion so as to be swingable in the axial direction and the centripetal direction, and the respective front edges are separated from each other with the swing in the centrifugal direction, and the central region of the valve opening is opened. Each trailing edge separates from the periphery of the valve opening and opens, and as the centering direction swings, each leading edge approaches and closes the central region of the valve opening, and each trailing edge closes the valve. A valve leaf that closes near the periphery of the mouth and at least one of the valve housing and the leaflet, and each leaflet with respect to an imaginary line that is orthogonal to the axis of the valve mouth when closed. A stopper portion for inclining the valve leaf, and a cross section at the time of valve closing in a direction connecting the front edge and the rear edge of the leaflet, Let L1 be the distance connecting in the direction parallel to the imaginary line, L0 be the distance connecting the leading edge and the trailing edge of the leaflet in the direction parallel to the imaginary line, and let the chord length of the leaflet be C0. When the maximum camper of the leaflet is C1, the axial position of the leaflet (%) = (L1 / L0) × 100, and the curvature (%) of the leaflet = (C1 / C0) × 100 The artificial valve for a living body, wherein the axial position of the leaflets is set to 67 to 73% and the curvature of the leaflets is set to 8 to 10%.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21052892A JPH0654868A (en) | 1992-08-06 | 1992-08-06 | Artificial valve for living body |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21052892A JPH0654868A (en) | 1992-08-06 | 1992-08-06 | Artificial valve for living body |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0654868A true JPH0654868A (en) | 1994-03-01 |
Family
ID=16590860
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP21052892A Pending JPH0654868A (en) | 1992-08-06 | 1992-08-06 | Artificial valve for living body |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0654868A (en) |
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WO2017200920A1 (en) * | 2016-05-19 | 2017-11-23 | Boston Scientific Scimed, Inc. | Prosthetic valves, valve leaflets and related methods |
US10195023B2 (en) | 2015-09-15 | 2019-02-05 | Boston Scientific Scimed, Inc. | Prosthetic heart valves including pre-stressed fibers |
US10299915B2 (en) | 2015-04-09 | 2019-05-28 | Boston Scientific Scimed, Inc. | Synthetic heart valves composed of zwitterionic polymers |
US10314696B2 (en) | 2015-04-09 | 2019-06-11 | Boston Scientific Scimed, Inc. | Prosthetic heart valves having fiber reinforced leaflets |
US10413403B2 (en) | 2015-07-14 | 2019-09-17 | Boston Scientific Scimed, Inc. | Prosthetic heart valve including self-reinforced composite leaflets |
US10426609B2 (en) | 2015-04-09 | 2019-10-01 | Boston Scientific Scimed, Inc. | Fiber reinforced prosthetic heart valve having undulating fibers |
US10433955B2 (en) | 2012-07-02 | 2019-10-08 | Boston Scientific Scimed, Inc. | Prosthetic heart valve formation |
US10716671B2 (en) | 2015-07-02 | 2020-07-21 | Boston Scientific Scimed, Inc. | Prosthetic heart valve composed of composite fibers |
US10925998B2 (en) | 2017-04-25 | 2021-02-23 | Boston Scientific Scimed, Inc. | Method of manufacturing a biocompatible composite material |
-
1992
- 1992-08-06 JP JP21052892A patent/JPH0654868A/en active Pending
Cited By (12)
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---|---|---|---|---|
US10433955B2 (en) | 2012-07-02 | 2019-10-08 | Boston Scientific Scimed, Inc. | Prosthetic heart valve formation |
US10299915B2 (en) | 2015-04-09 | 2019-05-28 | Boston Scientific Scimed, Inc. | Synthetic heart valves composed of zwitterionic polymers |
US10314696B2 (en) | 2015-04-09 | 2019-06-11 | Boston Scientific Scimed, Inc. | Prosthetic heart valves having fiber reinforced leaflets |
US10426609B2 (en) | 2015-04-09 | 2019-10-01 | Boston Scientific Scimed, Inc. | Fiber reinforced prosthetic heart valve having undulating fibers |
US11304798B2 (en) | 2015-04-09 | 2022-04-19 | Boston Scientific Scimed, Inc. | Prosthetic heart valves having fiber reinforced leaflets |
US10716671B2 (en) | 2015-07-02 | 2020-07-21 | Boston Scientific Scimed, Inc. | Prosthetic heart valve composed of composite fibers |
US10413403B2 (en) | 2015-07-14 | 2019-09-17 | Boston Scientific Scimed, Inc. | Prosthetic heart valve including self-reinforced composite leaflets |
US10195023B2 (en) | 2015-09-15 | 2019-02-05 | Boston Scientific Scimed, Inc. | Prosthetic heart valves including pre-stressed fibers |
WO2017200920A1 (en) * | 2016-05-19 | 2017-11-23 | Boston Scientific Scimed, Inc. | Prosthetic valves, valve leaflets and related methods |
US10368982B2 (en) | 2016-05-19 | 2019-08-06 | Boston Scientific Scimed, Inc. | Prosthetic valves, valve leaflets and related methods |
US11559394B2 (en) | 2016-05-19 | 2023-01-24 | Boston Scientific Scimed, Inc. | Prosthetic valves, valve leaflets and related methods |
US10925998B2 (en) | 2017-04-25 | 2021-02-23 | Boston Scientific Scimed, Inc. | Method of manufacturing a biocompatible composite material |
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