Percutaneous mitral commissurotomy is the reference treatment for rheumatic mitral stenosis. In high-income settings, mitral valve calcification is frequent. The CALCIMIT prospective multicenter study published in the European Heart Journal Cardiovascular Imaging assessed the reproducibility and prognostic value of computed tomography (CT)-derived Mitral Valve Calcium Scoring (MVCS) for immediate and long-term outcomes after PMC.

Between 2016 and 2019, 172 consecutive patients (mean age 56±15 years; 78% women) underwent non-contrast cardiac CT before PMC. MVCS was quantified using Agatston’s method. The primary endpoint was good immediate result (GIR), defined as final mitral valve area ≥1.5 cm² with ≥50% increase and ≤2/4 mitral regurgitation (MR). The secondary endpoint was long-term event-free survival, defined as survival free of death or mitral reintervention.

Mitral calcification was present in 66% (113/172) of patients. GIR achieved 54.7%. Independent predictors of GIR included lower CT-based MVCS, lower New York Heart Association class, and lower baseline mitral regurgitation grade. MVCS was independently associated with long-term survival free of mitral reintervention (HR 1.54; 95% CI 1.07–2.21; p=0.019). A threshold of 385.5 Agatston Units predicted both immediate and late outcomes. Interobserver reproducibility was excellent (calcification detection: Kappa 0.987; MVCS correlation: r=0.999).

CT-derived MVCS provided independent and reproducible prognostic information beyond echocardiographic scores. Integration of MVCS into preprocedural assessment may improve patient selection for PMC.