322 patients (66% women), average age: 35±13 years (9-75 years) having a tight MS and treated by PMC with Inoué balloon. The anatomic aspect of the mitral apparatus before PMC was studied according to the criteria of the Wilkins score with a concomitant study of the state of mitral commissures. The primary success of PMC was defined as follow: mitral area (MA) post-PMC >1,5cm2 and gain in MA >25% and mitral regurgitation (MR) ≤grade 2. Mitral restenosis was defined as a MA <1,5cm2 and/or loss >50% of initial gain in MA.
The rate of primary success of PMC was 86% and mean MA post PMC was 1,82±0,33cm 2 compared to MA pre-PMC of 1±0,18cm 2 (p<0.0001).
Opening of two commissures was observed in 74% of patients. After an average period of 62±32 months, only 12% of patients had a dyspnea stage III-IV of NYHA, MA was 1,64±0.3cm 2 (p<0.001) and mitral restenosis happened in 47 patients (20%) after a period of 60,48±27 months (22 – 124 months).
The independent predictors of mitral restenosis after a successful PMC were: previous surgical commisurotomy, Wilkins score >8, MA after PMC <1,8cm2 and absence of bicommissural opening post PMC.
A favorable anatomy of mitral apparatus and the optimisation of immediate result of PMC are the guaranty for the maintain of good result in the long term.