LEFT-VENTRICULAR OUTFLOW TRACT OBSTRUCTION AFTER MITRAL-VALVE REPAIR - RESULTS OF THE SLIDING LEAFLET TECHNIQUE

Background. Left ventricular outflow tract obstruction (LVOTO) occurs in 4% to 5% of patients after prosthetic ring mitral valve repair. Maj or anatomic factors incriminated in the genesis of LVOTO include degen erative mitral valve insufficiency with excess leaflet tissue, nondila ted left ventricular cavity, and narrow mitro-aortic angle. We have pr eviously reported a 14% incidence of LVOTO after prosthetic ring mitra l valve repair in this high-risk group of patients. Serial echo Dopple r studies demonstrated an overlapping and/or inversion of the left ven tricular functional compartments generating systolic anterior motion o f the posterior leaflet and paradoxical opening (eversion) of the ante rior leaflet. In an attempt to eliminate LVOTO after mitral valve repa ir, a new surgical procedure was developed in 1988 by Carpentier. the sliding leaflet technique, which reduces the height of the posterior l eaflet. The purpose of this study was to analyze the results of the ne w technique in terms of the occurrence of LVOTO. Methods and Results. Eighty-two patients undergoing prosthetic ring mitral valve repair bet ween 1988 and 1991 and identified as high risk for LVOTO were operated on using the sliding leaflet technique. There were 52 men and 30 wome n. Ages ranged from 28 to 75 years. The surgical techniques used inclu ded prosthetic ring annuloplasty (n=82), leaflet resection (n=82), cho rdal shortening or transposition (n=36), and other (n=19). Intraoperat ive and/or immediate postoperative echo Doppler studies were obtained in all cases. Two patients (2.4%) died, and 2 (2.4%) required reoperat ion. Nonsignificant LVOTO was identified in 2 cases (2.4%), in whom in stantaneous maximal subaortic gradients were 20 and 18 mm Hg, respecti vely. Conclusions. This study was not done on a concomitant series of patients but on patients with the same type of pathology. It demonstra tes that (1) the sliding leaflet technique eliminates significant LVOT O in the high-risk patients; (2) the sliding leaflet technique is asso ciated with a low mortality; and (3) no reoperations for mitral insuff iciency were required in this series.