Abstract
From July 1990 through September 1991, we performed 23 aortic valve replacements using CarboMedics valves. Operative death occurred in 1 case (4.3%) and hospital death in 1 case. There were no other deaths or valve-related complications.
Doppler echocardiography was used to measure the peak trans-valvular pressure gradient in 17 cases: The peak pressure gradient for the 21mm valves (n=7) was 22.5±12.6mmHg, while for the 23mm valves (n=6) it was 20.2±12.9mmHg and for the 25mm valves (n=4) it was 16.1±10.5mmHg (mean±SD).
Valve response to tachycardia was evaluated by observing the effects of right ventricular pacing in the trans-valvular pressure gradient and effective orifice area. This was done in 8 cases (3 cases with 21mm valves, 3 cases with 23mm valves and 2 cases with 25mm valves) using cardiac catheterization. Orifice areas calculated by the formula of Gorlin and Gorlin in these 8 cases measured 1.40±0.27cm2 at rest and 1.39±0.25cm2 at a pacing rate of 90 beats/min. When the pacing rate was increased to 130 beats/min, the orifice area decreased slightly to 1.29±0.23cm2.
From these results, we conclude that the CarboMedics valve prosthesis is suitable for aortic valve replacement.
