| 摘要 |
<p>A heart valve prosthesis (88; 128) having a plurality of leaflets (18, 20 and 22; 138, 140 and 142). The valve (10; 130) is covered with a sheath (90; 172) of natural tissue. The sheath (90; 172) extends from an inflow end (12; 132) of the valve (10; 130) beyond an outflow end (14; 134) of the valve (12; 132) to define a plurality of lobes (98, 100 and 102; 182, 184 and 186). A substantially flexible annular ring (60; 162) may be positioned between the sheath (90; 172) and the heart valve (10; 132) to provide additional stability.</p> |
