Effectiveness of percutaneous mechanical mitral commissurotomy using the metallic commissurotome in patients with restenosis after balloon or previous surgical commissurotomy

Balloon mitral valvuloplasty has been reported to give equal or less positive results after previous commissurotomy than after a first procedure. Percutaneous mechanical mitral commissurotomy (PMMC) is a new technique that has not yet been evaluated in this subset of patients. Of 1,175 PMMC procedures (1,175 patients), 173 patients (14.7%) had previous commissurotomy; patients were older (40 vs 35 years of age, p <0.0001) and more often in atrial fibrillation (34% vs 21%, p = 0.0016) than were patients who had not undergone previous commissurotomy. The baseline transmitral gradient was lower (17 ± 8 vs 19 ± 8 mm Hg, p <0.002) and the echocardiographic Wilkins score was higher (8.7 ± 1.9 vs 7.6 ± 1.8, p <0.0001) for patients who underwent previous commissurotomy. Baseline mitral valve area was comparable between the 2 groups (0.96 ± 0.21 vs 0.93 ± 0.24 cm2). Immediate results were satisfactory, although slightly less favorable after previous commissurotomy, with a final mitral valve area of 2.01 ± 0.30 versus 2.12 ± 0.36 cm2 (p <0.0001), and a residual transvalvular gradient of 5.0 ± 3.6 versus 4.2 ± 4.1 mm Hg (p = 0.003). The rates of procedural success (93%) and severe complications (4.7%) were comparable between the 2 groups. Thus, PMMC is an effective and safe technique for the treatment of mitral restenosis after previous commissurotomy.