| 摘要 |
A bioprosthetic heart valve comprising leaflets with free edges which do not impinge on adjacent leaflets when the leaflets are closed before being implanted and subject to body fluids and cardiac pressure cycles. Commissures supporting the leaflets have semi-permeable membranes which reduce the pressure load on the leaflets during implantation. In response to immersion in body fluids, the membranes become substantially impermeable. The leaflets can stretch in response to loads and hydration, so that the free edges mate shortly after implantation. First and second mechanisms for supporting leaflets to provide multiple effective spring constants. An inner frame supporting commissures of the valve is elastic, permitting the commissures to bend in toward the center of the prosthetic heart valve at very low loads. A relatively rigid annular support ring supports the elastic frame and provides the second spring constant mechanism. The leaflets have an uncoupled mating edge where the leaflet approach each other in the center of the valve.
|
