04204283 is referenced by 84 patents and cites 4 patents.

A prosthetic valve, suitable for use as a mitral valve replacement, has a D-shaped annular seat-forming member and obturating flap, the flap having a major area formed by a rigid sheet of similar D-shape and extent for direct support on the seat when the valve is closed, and a flexible sheet hinge connecting the flap and annular member as a hinge along their straight edge portions. The rigid sheet is preferably scalloped around its free edge, with a flexible skirt being located across the incursions of this shaping, and is also preferably dished inwardly towards the valve.

Title
Prosthetic valve
Application Number
5/902746
Publication Number
4204283
Application Date
May 3, 1978
Publication Date
May 27, 1980
Inventor
William G Williams
Islington
CA
Brian J Bellhouse
Islip
GB
Agent
Cushman Darby & Cushman
Assignee
National Research Development Corporation
GB
IPC
A61F 1/22
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