Background: Mitral restenosis often occurs within 5 to 15 years of surgical valvotomy. Percutaneous balloon mitral valvotomy is well established as a safe and effective alternative to mitral stenosis surgery, but only a few small studies have reported on the procedure.
Aim: (i) To evaluate the safety and efficacy of percutaneous balloon mitral valvotomy in patients with mitral restenosis. (ii) To evaluate the intermediate-term outcome of patients undergoing balloon mitral valvotomy after previous surgical valvotomy. (iii) To compare these patients with those undergoing balloon mitral valvotomy as the initial procedure.
Methods: We analysed our experience of 614 consecutive patients undergoing balloon valvotomy and identified 84 patients (13.7%) with mitral restenosis following prior surgical valvotomy (Group I). The remaining 530 patients (86.3%) had not undergone previous surgery (Group II). The incidence of atrial fibrillation (19% vs 5.6%), mitral valve calcification (50% vs 30.6%) and total echo score > 8 (54.8% vs 24.15%) was significantly higher in Group I. Both groups were comparable as regards their functional class, technique of valvotomy, mitral valve area (0.87 +/- 0.18 vs 0.87 +/- 0.15 cm2, P = ns), mean transmitral gradient (19.63 +/- 6.01 vs 19.21 +/- 5.67 mmHg, P = ns), and mean pulmonary artery pressure (42.2 +/- 19.0 vs 40.8 +/- 14.4 mmHg, P = ns).
Results: After percutaneous balloon mitral valvotomy, the final mitral valve area (1.67 +/- 0.28 vs 1.69 +/- 0.29 cm2, P = ns), mean transmitral-mitral gradient (6.12 +/- 3.68 vs 5.02 +/- 3.21 mmHg, P = ns) and mean pulmonary artery pressure (31.0 +/- 15.2 vs 28.5 +/- 11.1 mmHg, P = ns) were comparable. The success rate (93.0% vs 95.3%, P = ns) were similar in both groups. Significant mitral regurgitation was seen in four (4.8%) patients in Group I and 22 (4.1%) patients in Group II (P = ns). There were two deaths (2.4%) in Group I and five (0.9%) in Group II (P = ns). The clinical and echo Doppler follow-up (8-40 months) studies showed that both groups were of similar NYHA class, and had similar mitral valve area (1.65 +/- 0.21 vs 1.66 +/- 0.3 cm2) and transmitral gradients (7.1 +/- 3.8 vs 5.9 +/- 3.5 mmHg).
Conclusion: We conclude that percutaneous balloon mitral valvotomy can be performed safely and effectively in patients with mitral restenosis following surgical valvotomy; the beneficial acute outcome is sustained, as shown at intermediate-term follow-up and is similar to that of patients undergoing balloon mitral valvotomy as an initial procedure.