Hemodynamic evaluation of a new stentless autologous pericardial mitral valve

Background. There is no satisfactory mitral valve prosthesis. An ideal mitr al valve substitute should be biologic, nonantigenic, and anatomically corr ect. Methods. We developed a stentless, chordal-supported (including anterior ba sal stay chords) mitral valve made with glutaraldehyde-treated autologous p ericardium. Eight such prostheses were implanted in sheep. Results. Seven animals survived the operation and were studied postoperativ ely immediately, at 1 week, and at 1 month. Simultaneous left ventricular a nd left atrial pressures showed peak and mean transvalvular pressure gradie nts of 6 +/- 2 mm tig and 1 +/- 1 mm Hg, respectively. Echocardiography per formed intraoperatively and then 1 week and 1 month postoperatively showed normal valve leaflet movements. Color and pulsed Doppler echocardiography s howed no sign of transvalvular stenosis or regurgitation. Effective orifice area was 5.39 +/- 0.35 cm(2) at intraoperative, 5.51 +/- 0.29 cm(2) 1 week after operation (n = 5), and 5.51 +/- 0.28 cm(2) 1 month after operation ( n = 3). Three animals were sacrificed at 19 days and at 1 and 3 months. One animal is alive at 10 months. Conclusions. This new stentless pericardial mitral valve performed satisfac torily with low gradients and no regurgitation. Possible advantages of this pericardial valve are excellent hemodynamics, ease of construction and imp lantation, lack of immunogenicity, and low cost. Similarly designed valves but with a shorter nonglutaraldehyde treatment time have been used in 3 she ep monitored for more than 3 months. (C) 2001 by The Society of Thoracic Su rgeons.