Clinical and hemodynamic results after combined aortic and mitral valve replacement with the Lillehei-Kaster pivoting disc valve.

Combined mitral and aortic valve replacement with the Lillehei-Kaster pivoting disc valve prosthesis was performed in 23 patients. Hospital mortality rate was 8.3 per cent. Detailed postoperative clinical and hemodynamic studies were performed after a mean follow-up period of 24.4 months. Replacement of both valves had resulted in a marked symptomatic and hemodynamic improvement with a normal or nearly normal resting value of cardiac output, pulmonary arterial pressure, and pulmonary vascular resistance while left ventricular end-diastolic pressure (LVEDP) had increased significantly. The rise in left ventricular end-diastolic pressure most probably might be related to the simultaneous rise in cardiac output (Starling mechanism), reflecting the severity and irreversibility of the underlying myocardial disease. Most patients also had systolic gradient across the aortic prosthesis, as well as diastolic gradient across the mitral prosthesis. The gradients across the mitral prosthesis were approximately the same as seen after single valve replacement, while the pressure gradients across the aortic prosthesis were somewhat smaller than previously reported. Angiographic studies of the aortic valve movement indicated that the opening angle of the disc was approximately 60 degrees, and thus less than according to the valve specifications.