PERCUTANEOUS MITRAL COMMISSUROTOMY DURING PREGNANCY

This report analyses the efficacy and tolerance of percutaneous mitral commissurotomy (PMC) in 10 pregnant women with severe mitral stenosis. Pregnancy was the cause of decompensation of the mitral stenosis and surgery was not considered because of the foetal risk. PMC was undertaken after an average of 26 +/- 4 weeks of gestation (range 23-33 weeks). The average age of the patients was 28 +/- 6 years (range 20-41 years). Six patients were in NYHA Class III and 4 in Class IV despite medical treatment. Five patients had mild mitral regurgitation. Foetal protection was ensured by covering the mother's abdomen with a lead apron. The double balloon technique was used in 4 cases and Inoue's balloon in 6 patients. The average duration of fluoroscopy was 17 +/- 10 minutes (range 6-37 minutes). After PMC, the mean pulmonary artery pressure decreased from 47 +/- 12 mmHg to 31 +/- 11 mmHg (p = 0.005); two dimensional echocardiography showed an increase in mitral valve surface area from 1 +/- 0.2 cm2 to 2 +/- 0.3 cm2 (p = 0.005). There were no complications related to the procedure. The foetal heart rate was monitored continuously and no significant modification suggestive of foetal distress was recorded. The abdominal cutaneous dose of irradiation was less than 0.2 millisievert, which was minimal. All patients experienced a functional improvement after PMC. Nine delivered after an average gestation of 38 +/- 2 weeks (range 36-42 weeks) without cardiac decompensation. The average birth weight of the babies was 3.1 +/- 0.3 kg (range 2.9-3.7 kg). One neonatal death occurred 3 months after PMC after a caesarian section performed at 29 weeks of gestation for obstetrical reasons. These results show that PMC is effective and well tolerated and may be offered to pregnant women who remain symptomatic despite medical treatment.