Four-year follow-up of patients undergoing percutaneous balloon mitral commissurotomy. A report from the National Heart, Lung and Blood Institute Balloon Valvuloplasty Registry

Objectives. This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry. Background. The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short and long-term safety and efficiency of percutaneous balloon mitral commissurotomy. Methods. Between November 1987 and October 1989, 736 patients ≤18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years. Results. The actuarial survival rate was 93 ± 1% (mean ± SD), 90 ± 1.2%, 87 ± 1.4% and 84 ± 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomv at 1 year. The event-free survival rate was 80 ± 1.5% at 1 year, 71 ± 1.7% at 2 years, 66 ± 1.8% at 3 years and 60 ± 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age >70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01). Conclusions. Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients.