[Complications of percutaneous mitral commissurotomy. Personal experience and review of the literature].

Percutaneous mitral commissurotomy was performed in 484 patients by the double balloon technique and by Inoue's technique in 33 patients. The average age of the patients was 33.6 +/- 13 years (range: 8 to 72 years); 30% were in atrial fibrillation. A primary failure was observed in 10 patients (2%). The acute mortality was 0.4% and first month mortality 0.6%, the main cause being perforation of the left ventricle. The incidence of systemic embolism was 2%, related to atrial fibrillation (p < 0.016); this complication disappeared after systematic utilisation of transoesophageal echocardiography. Grade 4+ mitral regurgitation was created in 5 patients (1%) and grade 3+ in 20 others (3.9%). A score > 8 (p < 0.006) and preexisting grade 1+ mitral regurgitation (p < 0.005) were predictive factors of these severe regurgitations. They were also more frequent with Inoue's technique (10.5%; p < 0.05). Surgical intervention was necessary during the first month in 5 patients and at long-term (38 +/- 24 months) in 15 others. A tear in the anterior leaflet and ruptured chordae tendinae were the main mechanisms. The most common minor complication was the creation of a small interatrial shunt (16%) without any immediate or long-term complications. With a major complication rate of 4.2%, the mitral surface area increased from 0.97 to 2.2 cm2 and the cardiac index from 3 to 3.6 l/min/m2; left atrial pressure fell from 27 to 15 mmHg (p < 0.0001): the incidence of residual stenosis was only 2%. Seventy nine per cent of patients were asymptomatic and 16% were paucisymptomatic (class II) at long-term. Systematic transoesophageal echocardiography to detect thrombi, the use of pig-tail or Inoue catherters, effective heparinisation during a prolonged procedure and improved experience of the medical teams, should result in a further reduction of the risks of percutaneous mitral commissurotomy.