Surgical repair of congenital mitral valve malformations in infancy and childhood: a single-center 36-year experience

Objective: We sought to evaluate the results of surgical repair and determine predictors for the late outcome of congenital mitral valve dysplasia.

Methods: Preoperative, operative and postoperative data were obtained from an institutional database; follow-up data came from regular clinical evaluation at our institution or elsewhere. Patients were divided into isolated and complex cases according to the complexity of associated lesions.

Results: Between 1972 and 2008, 93 patients (43 male and 50 female patients) underwent mitral repair (median, 4.5 years; range, 0.16-19.8 years). Predominant mitral regurgitation was present in 52%. Associated cardiac anomalies were present in 72%. Sixty-one patients were in the complex group. All patients underwent successful mitral repair. Surgical repair was tailored to the patient's valve anatomy. Early death was 7.5%. The postoperative course was uneventful in 86% of patients. At a mean follow-up of 10.3 years (median, 8.4 years; completeness, 94%), late mortality is 8% (7 patients). Twelve patients underwent mitral reintervention (11 replacements and 1 repair). Among the 80 survivors, 82.5% were in New York Heart Association class I or II, and 61.2% had some degree of persistent mitral regurgitation or stenosis, despite stable hemodynamics. Stenosis is a statistically significant risk factor for surgical intervention at less than 1 year of age and is related to higher overall mortality and incidence of late cardiac failure and mitral dysfunction; parachute mitral valve is related to higher mortality and morbidity.

Conclusions: Mitral valve repair shows acceptable early mortality and reoperation rates. Mitral malformations in the complex group are related to a significantly higher risk of reoperation on the mitral valve. Parachute mitral valve is associated with a higher rate of early mortality.