A Hemodynamic Study of the Carpentier-Edwards and Hancock Porcine Xenografts in the Mitral Position

Abstract
A hemodynamic study was performed on 11 female and 3 male patients with porcine xenograft (9 Carpentier-Edwards, 5 Hancock) in mitral position on average 32.5 mo. (range 10-65 mo.) after the operation. In comparison with the preoperative values, the following parameters showed statistically significant postoperative decrease (mean values): wedge pressure (from 22.9 to 13.7 mmHg), pulmonary artery pressure (33.6-21.7), right atrial pressure (7.1-4.2) and pulmonary vascular resistance (3.6-1.9 mmHg/l per min). In a supine bicycle exercise test the mean wedge pressure rose to 27.8 (range 15-44) mmHg. The transvalvular average diastolic gradient showed a mean value of 6.9 (range 4-12 mmHg). The corresponding figures for the calculated valve area were 2.0 (1.0-3.5) cm2. A biplane left ventriculography showed no valvular or paravalvular regurgitation to the left atrium in any patient. The wedge pressures during exercise were significantly correlated with graft diameters. The results were compared with previous reports on mechanical and biological mitral prostheses, and it was concluded that implantation of a porcine xenograft in the mitral position is a satisfactory procedure in severe mitral disease.