Hemodynamic Findings Following Replacement of the Mitral Valve with the University of Cape Town Prosthesis

Abstract

The insertion of the University of Cape Town prosthetic mitral valve in patients severely disabled results in marked clinical and haemodynamic improvement, marred only by the high incidence of systemic embolisation. Post-operative haemodynamic studies revealed in 11 patients that the valve is mildly stenotic but completely competent. The residual pressure gradient across the prosthesis is related to the size of the prosthesis used, but inertial delay in valve opening may be a factor contributing to the residual obstruction. Severe pulmonary hypertension was found to be reversible when the left atrial hypertension was relieved. Poor left ventricular function appeared to be present in 3 cases and was unexplained in one.