A 30-year-old woman with rheumatic mitral stenosis (valve area 1.0 cm², moderate-severe MS) becomes pregnant at 14 weeks. She is in NYHA Class II–III despite medical therapy with beta blockers and diuretics. She develops increasing dyspnoea at 22 weeks. What is the preferred intervention, and what is the Wilkins score's role in selecting this?

• A Closed mitral commissurotomy under cardiopulmonary bypass is the standard approach in pregnancy
• B Elective cesarean section at 34 weeks followed by PBMV in the postpartum period
• C Open mitral valve replacement (MVR) with bioprosthetic valve preferred at 22 weeks
• D Percutaneous balloon mitral valvotomy (PBMV) is preferred if Wilkins score ≤8; performed with lead shielding and minimal fluoroscopy time after 12 weeks ✓

Explanation

For symptomatic severe mitral stenosis in pregnancy (MVA ≤1.5 cm², or ≤1.0 cm² as here, refractory to medical therapy), PBMV (Inoue balloon technique) is the preferred intervention when anatomy is suitable. The Wilkins score assesses mitral valve anatomy (leaflet mobility, thickening, calcification, subvalvular disease) on a scale of 4–16; a score ≤8 predicts good outcome from PBMV. It is performed ideally after 12–14 weeks (organogenesis complete) with careful radiation minimisation using abdominal lead shielding. Open heart surgery with cardiopulmonary bypass carries a 20–30% fetal mortality risk and is reserved for cases where PBMV fails or anatomy is unsuitable.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.