BUBBLE HEART VALVE

摘要

A novel bileaflet mitral heart valve is provided herein, which. in two alternative embodiments, may have symmetrical leaflets or asymmetrical leaflets. The valve has a stent including a circular base and a pair of upstanding struts separating a pair of arcuately-shaped, depressed, reliefs, each such relief being bounded by a smooth curve interconnecting the struts to the circular base. A flexible, durable, bicompatible covering. e.g. a pericardial covering, is secured to the stents and provides two opposed moulded, flexible. flappably-movable valve leaflets secured along the smooth curve defining the upper perimeter of the reliefs. These valve leaflets each are preformed and moulded so that the free margin of the biocompatible leaflets along the free edge of each of the leaflets between the tips of the struts is related to the circumference of the circular base such that, when the valve is in the open position, the cross-sectional area is substantially equal to the inside cross-sectional area of the circular base, and when the valve is in its relaxed and natural closed position, the free edges of the leaflets drop down and sealingly meet in substantially wrinkle-free form at a curve of apposition, preferably in the plane defined by the tip of the struts and the axis of the valve. to provide symmetrical leaflets, and, in one embodiment. may follow the approximate shape of a catenary curve. The shape of the leaflets in that closed position approximates (continued) that of a surface formed by two coapting bubbles under pressure. That shape is defined by five simultaneous equations as disclosed herein. The two leaflets may thus approach the configuration of the natural human mitral valve.