Which patients benefit from percutaneous mitral balloon valvuloplasty? Prevalvuloplasty and postvalvuloplasty variables that predict long-term outcome

Background-Percutaneous mitral balloon valvuloplasty (PMV) results in good immediate results, particularly in patients with echocardiographic scores (Echo-Sc) less than or equal to8. However, which variables relate to long-term outcome is unclear. Methods and Results-We report the immediate and long-term clinical follow-up (mean, 4.2 +/- 3.7 years; range, 0.5 to 15) of 879 patients who underwent 939 PMV procedures. Patients were divided into 2 groups, Echo-Sc less than or equal to8 (n=601) and Echo-Sc >8 (n=278). PMV resulted in an increase in mitral valve area from 1.0 +/- 0.3 to 2.0 +/- 0.6 cm(2) in patients with Echo-Sc less than or equal to8 and from 0.8 +/- 3 to 1.6 +/- 6 cm(2) in patients with Echo-Sc >8 (P<0.0001). Although adverse events (death, mitral valve surgery, and redo PMV) were low within the first 5 years of follow-up, a progressive number of events occurred beyond this period. Nevertheless, survival (82% versus 57%) and event-free survival (38% versus 22%) at 12-year follow-up was greater in patients with Echo-Sc >58 (P<0.0001). Cox regression analysis identified post-PMV mitral regurgitation greater than or equal to3+, Echo-Sc >8, age, prior surgical commissurotomy, NYHA functional class IV, pre-PMV mitral regurgitation greater than or equal to2+, and higher post-PMV pulmonary artery pressure as independent predictors of combined events at long-term follow-up. Conclusions-The immediate and long-term outcome of patients undergoing PMV is multifactorial. The use of the Echo-Sc in conjunction with other clinical and morphological predictors of PMV outcome allows identification of patients who will obtain the best outcome from PMV.