DOPPLER-ECHOCARDIOGRAPHIC STUDIES ON PORCINE MITRAL-VALVES 7-14 YEARSAFTER IMPLANTATION

Thirty-two adult patients with Hancock bioprosthetic heart valve in th e mitral position were investigated with Doppler echocardiography. The patients included the total number of available patients who had thei r valve implanted at our hospital between 1975 and 1977. The mean time interval since implantation was 10 years (range 7-14). At the time of restudy, 26 patients were asymptomatic while 6 were symptomatic (NYHA class II-IV). Three parameters of flow were assessed: maximum diastol ic left ventricular inflow velocity (V(max)), mean valvular pressure g radient (MVG), and pressure half-time (P1/2). V(max) varied between 13 0 and 340 cm s-1 with a mean value of 200 +/- 45.0 cm s-1, MVG varied between 2 and 24 mm Hg with a mean value of 6.7 +/- 5.0 mm Hg and P1/2 between 80 and 219 ms with a mean value of 149 +/- 40.0 ms. The 6 sym ptomatic patients had significantly higher values for V(max) and for M VG than the 26 asymptomatic patients, while the difference in P1/2 bet ween the two subgroups was insignificant. None of the 3 parameters und er study correlated significantly with the prosthesis age or size.