Aortic valve replacement. A randomized study comparing the Björk-Shiley and Lillehei-Kaster disc valves. Peroperative haemodynamic evaluation and early results.

Three hundred patients were selected at random in order to compare the Björk-Shiley and the Lillehei-Kaster valves in the aortic position. Peroperative haemodynamic evaluations were carried out in 106 cases. The effective orifice area of the valves and the effective area index were calculated. The results indicate that the Björk-Shiley valves utilize the available space in the aortic root about 12% better than the Lillehei-Kaster valves. There were 11 hospital deaths, but none of them were valve related.