Percutaneous mitral balloon valvotomy in patients with calcific mitral stenosis: immediate and long-term outcome.

OBJECTIVES: This study analyzed the immediate and long-term outcome of percutaneous balloon mitral valvotomy in patients with and without fluoroscopically visible mitral valve calcification.

BACKGROUND: Mitral valve calcification has been shown to be an important factor in determining immediate and long-term outcome of patients undergoing surgical mitral commissurotomy. Patient selection has an important impact on the outcome of percutaneous balloon mitral valvotomy.

METHODS: The immediate and long-term results of percutaneous balloon mitral valvotomy were compared in 155 patients with and 173 patients without mitral valve calcification. The patients with calcified valves were assigned to four groups according to severity of calcification.

RESULTS: Patients with calcified mitral stenosis more frequently were in New York Heart Association functional class III or IV and more frequently had atrial fibrillation, previous surgical commissurotomy, echocardiographic score > 8, higher pulmonary artery and left atrial pressures, higher pulmonary vascular resistance and mean mitral valve gradient and lower cardiac output and smaller mitral valve area. Mitral valve area after valvotomy was significantly smaller in patients with calcified valves (1.8 +/- 0.06 vs. 2.1 +/- 0.06 cm2) and was > or = 1.5 cm2 in 65% of patients with and 83% of patients without calcified valves (p = 0.004). A successful outcome, defined as mitral valve area > 1.5 cm2 without significant mitral regurgitation and left to right shunting, was achieved in 52% of patients with and 69% of patients without uncalcified valves (p = 0.001). The success rate was 59%, 48%, 35% and 33% in subgroups with 1+, 2+, 3+ and 4+ calcification, respectively. The rates of significant left to right shunting and mitral regurgitation after valvuloplasty were similar in the two groups. Estimated survival rate (80% vs. 99%, respectively, p = 0.0001), survival rate without mitral valve replacement (67% vs. 93%, respectively, p < 0.00005) and event-free survival rate (63% vs. 88%, respectively, p < 0.00005) at 2 years were significantly better in the patients with uncalcified valves. Survival rate curves became progressively worse as the severity of calcification increased.

CONCLUSIONS: These findings indicate that immediate and long-term results of mitral valvuloplasty are not as successful in patients with fluoroscopically visible mitral valve calcification as in those without calcification.