In developing countries, mitral stenosis (MS) is the most common valvular heart disease revealed by pregnancy. Since cardiac surgery is very risky in this case, percutaneous mitral balloon commissurotomy (PMC) is currently the treatment of choice.

We aimed to evaluate the immediate, medium and long-term results of PMC in pregnant women with severe MS.

This was a retrospective study that included 20 pregnant women suffering from severe MS, hospitalized in the cardiology department of a tertiary care center, and treated by PMC during last two decades.

Mean patients age was 31.5±4.6 years. The PMC was performed on average 27.5±1.8 weeks of pregnancy. Functional improvement was observed immediately after successful PMC. Mitral valve area increased from 1.01±0.1cm² averaged to 1.89±0.3cm² (P<0.01). Mean transmitral gradient decreased from 17.9±5.8mm Hg to 8.05±4.3mm Hg (P<0.01). Systolic pulmonary arterial pressure decreased from 64.85±16.4mm Hg to 39.15±13.15mm Hg (P<0.01). Mitral regurgitation (MR) increased in nine cases and appeared in eight cases. We noticed no severe MR during the procedure in all cases. Seventeen patients delivered at term. Newborns were all healthy. Four of them had a low birth weight. On the long term follow-up (133.35±77.3months), five patients had mitral restenosis, one patient underwent a second PMC and the four other patients had a surgical valve replacement. Predictive factors of restenosis were Wilkins score ≥8 and partial or absent commissural opening during procedure. These results were comparable to those observed in a population of non-pregnant women who underwent PMC during the same period.

It is clear that PMC is an effective technique in the management of MS during pregnancy. The ultimate goal is to improve the hemodynamic situation of the patient in order to pursue the pregnancy and to get better conditions for childbirth.