Percutaneous balloon mitral valvotomy in mitral restenosis.

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.