Hemodynamic results, clinical outcome, and complications of Inoue balloon mitral valvotomy.

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 290 patients enrolled from 16 clinical centers in the United States and Canada. The mean age was 54 +/- 15 years and the mean total echocardiographic score was 7.3 +/- 2.8. Mitral valve dilatation resulted in an increase in mitral valve area from 1.0 +/- 0.3 to 1.7 +/- 0.6 cm2 (P < 0.001). Technical success, defined as final mitral area > or = 1.5 cm2 or a > or = 50% increase in area, was achieved in 83% of patients. Significant complications included mitral valve replacement in the hospital 1.0% and hospital death in 1.4%. Failure to cross the mitral valve occurred in 1.7%. Other complications that did not interfere with discharge from the hospital with a completed PTMC procedure occurred in 12.1% of patients. Among patients with successful PTMC, the valve area remained constant over a 24-month follow-up period. Although a minority of patients were NYHA Class I or II prior to PTMC, > 80% remained in Class I or II throughout the 2-yr follow-up period. The overall results in this registry demonstrate that the acute hemodynamic results of the procedure are excellent, the incidence of procedure related complications is acceptable, and a majority of patients remain symptomatically improved during a 2-yr follow-up period.