[Artificial cardiac valve with curved disc (author's transl)].

Abstract

Because of insufficient opening of Björk-Shiley- and Lillehei-Kaster-prostheses in vitro and in vivo a new pendulum valve is proposed. The skeleton line of the disc crossection is bent towards the main flow direction when the valve is closed. Thus during valve opening the blood stream is directed to the opposite of the opening direction as to add torque to the disc which enables complete valve opening. During flow observations in an open water table with eight different curved discs an increase of the opening angle with which the torque disappears could be measured with increasing curve of the disc. The pressure loss of the valve is smaller in comparison to the pressure loss of pendulum valves with plane or contrarily curved discs. Furthermore the curvature decreases the backflow volume during valve closure.