Open aortic bioprosthesis at zero pressure. A new concept in glutaraldehyde fixation of tissue valve

An experimental trial has been made to fix a porcine aortic valve in a semi-open position using 1 percent glutaraldehyde (open model). Four valves of open model xenograft were examined with use of our pulse-simulator. Four valves fixed in the closed position (closed model) and one untreated valve were studied for comparison. Comparison of the opening characteristics at the pump pressure of 120 gr/sq.cm revealed the significant difference in that the open model valves gave the simultaneous cusp opening with a circular orifice, while the closed model valves opened in sequence with irregular orifice. This relationship was substantiated by forward flow measurement. Analysis of the flow velocity curve confirmed the competence of the open model xenograft. These results suggest that the open aortic bioprosthesis may provide an improved hemodynamic function under low flow conditions.