Percutaneous balloon mitral valvotomy in pregnant patients with tight pliable mitral stenosis.

Percutaneous balloon mitral valvotomy was attempted in severely symptomatic (New York Heart Association class III or IV) pregnant patients (mean age 30 years) with tight mitral stenosis. Nineteen patients were pregnant (mean gestation 30 weeks, range 26 to 34) and one patient was in the immediate postpartum period. All patients had undergone a trial of diuretic therapy and 16 were also taking atenolol. Percutaneous valvotomy was performed with the Inoue catheter (18 patients) or the Schneider-Medintag bifoil (2 x 19 mm) balloon catheter (2 patients). The fluoroscopy time was 9.2 +/- 3.4 minutes. After percutaneous valvotomy the mean mitral gradient decreased from 17.9 +/- 6.2 to 5.9 +/- 2.4 mm Hg (p < 0.001). The mitral valve area (pressure half time) increased from 0.8 +/- 0.2 to 1.7 +/- 0.2 cm2 (p < 0.001). These hemodynamic changes were accompanied by immediate symptomatic improvement by at least one New York Heart Association functional grade in all patients. Moderate (3+) mitral regurgitation developed in one patient. Eighteen patients had normal infants delivered vaginally at term without assistance, and one patient had a normal infant delivered by cesarean section at 35 weeks' gestation. We conclude that percutaneous balloon mitral valvotomy for pliable mitral stenosis in pregnancy is safe for both the mother and fetus. We recommend that it be performed in symptomatic patients with tight mitral stenosis so as to avoid hemodynamic complications in the latter stages of pregnancy.