Congenital mitral stenosis with or without associated defects - An evolving surgical strategy

Background-Congenital mitral stenosis (CMS) remains a surgical challenge, p articularly when it is associated with other heart defects. As in other gro ups of heart defects, there is a trend toward early single-stage complete r epair, but the optimal surgical approach remains unanswered. Methods and Results-This study was designed to analyze the evolution of sur gical strategies in patients with CMS and associated defects through single -stage and staged repair. Between 1980 and 1999, 72 children were operated on for congenital heart defects, including CMS. Preoperative transmitral gr adient was 12.6+/-7 mm Hg. Preoperatively, all the patients were NYHA class In to IV. Thirteen patients had an isolated CMS; in 59, it was associated with other heart defects, mainly ventricular septal defect (n=28) or multil evel left ventricular obstruction (n=41). In this group of patients, 33 had a staged approach, and 16 had a single-stage approach. Early mortality was 12.5% (9 patients). There were no deaths in the isolated CMS and single-st age repair groups. Logistic regression revealed that early mortality was in fluenced by association with left ventricular outflow tract obstruction (P< 0.001) and by use of a staged approach (P<0.01). There was no late mortalit y in isolated CMS; there were 2 late deaths in the group of single-stage re pair and 6 late deaths in the staged approach group (P<0.01). Reoperation w as required in 24 patients, mainly for residual mitral valve dysfunction or residual left ventricular outflow tract obstruction. Including the reopera tions, 10 patients received a prosthetic mitral valve. At 15 years after su rgery, survival was 69.6+/-7.5%, freedom from reoperation was 70.8+/-6.3%, and freedom from mitral valve replacement was 69+/-6%. Conclusions-Surgery for isolated CMS gives excellent early and long-term re sults. In patients with associated heart defects, a single-stage operation seems superior to a staged approach. Mitral valve replacement in this categ ory of patients should be reserved as a salvage procedure.