Does the Björk-Shiley prosthetic aortic valve improve hydrodynamic performance compared to other prosthetic valves in an in vitro pulse duplicator system?
In an in vitro pulse duplicator system, the Björk-Shiley prosthetic aortic valve demonstrated superior hydrodynamic performance with lower flow resistance, lower energy loss, and predominantly laminar flow compared to four other prosthetic valves.
A pulse duplicator system, used for studying prosthetic heart valves, is described. It provides a pulsatile flow resembling that produced by the heart, and permits a quantitative estimation of fluid flow resistance, regurgitation and energy loss in the valves. A technique for visualization of flow pattern is presented. The hydrodynamic performance of five prosthetic aortic valves, Starr-Edwards, Smeloff-Cutter, Kay-Shiley, Wada-Cutter and Björk-Shiley, were studied in the pulse duplicator and compared on the basis of their external (tissue) diameters. For a given tissue diameter, the Björk-Shiley valve had the best performance, resulting in a significantly lower flow resistance and energy loss than in the other prostheses investigated. All valves had acceptably low degrees of regurgitation with the exception of the Wada-Cutter prosthesis (16 to 20% of stroke volume). Flow visualization demonstrated a more or less turbulent flow pattern in all the valves with the exception of the Björk-Shiley valve. In this valve, predominantly laminar flow was observed.
Christian Olin (Fri,) studied this question.