[Evaluation of paravalvular leakage occurring after the 3rd mitral valve replacement]

We evaluated the frequency of paravalvular leakage (PVL) in 21 patients who had undergone mitral valve replacement (MVR) 3 times or more in our department between January 1981 and December 2003. Of these 21 patients, 5 underwent MVR 4 times, including the one who underwent the 5th MVR. Seven (38%) of 18 patients who had successfully undergone MVR 3 times and all 2 patients who had successfully undergone MVR 4 times developed PVL. PVL recurred in 6 (67%) of 9 patients who had undergone the 3rd MVR due to the occurrence of PVL. However, PVL recurred in only 1 (11%) of 9 patients who had undergone the 3rd MVR due to some postoperative complications other than PVL. Among 10 patients who developed PVL after the 1st or 2nd MVR, PVL recurred in 7 patients after the 3rd MVR. However, among 8 patients who did not develop PVL after the 1st or 2nd MVR, PVL occurred after the 3rd MVR only in 1 patient. These findings suggest that repeated MVR increases the incidence of PVL, and that patients with a past history of PVL are at a higher risk of developing PVL after repeated MVR.