Mitral Annular Calcification (MAC) as a Predictor of Successful Percutaneous Transvenous Mitral Commissurotomy (PTMC) Outcomes

Background: Percutaneous Transvenous Mitral Commissurotomy (PTMC) is the preferred treatment for severe mitral stenosis (MS) in patients with favorable valve morphology. Mitral Annular Calcification (MAC) may adversely affect procedural success and increase post-procedural mitral regurgitation (MR). Objective: To evaluate the impact of Mitral Annular Calcification on post-PTMC outcomes. Methodology: This mixed retrospective and prospective study was conducted at Peshawar Institute of Cardiology from April 2021 to December 2024. A total of 303 patients with severe MS (MVA ≤1.0 cm², mean gradient >10 mmHg) were included. Echocardiographic parameters including Wilkins and commissural scores were assessed. Procedural success was defined as post-PTMC MVA >1.5 cm², ≥50% increase in MVA, and absence of severe MR or major complications. Data were analyzed using SPSS 26. Results: Mean age was 38.88±11.38 years; 80.9% were females. Wilkins score ≤8 was observed in 82.8%, and 63% had no commissural calcium. Mean MVA increased from 0.92±0.16 cm² to 1.8±0.31 cm²; 91.7% achieved procedural success. Severe MR occurred in 11.2%, with one mortality. Commissural score correlated positively with MR (r=0.475, p<0.001) and negatively with MVA (r=–0.398, p<0.001). Patients with commissural score 2 had a 5.24-fold higher risk of severe MR (p=0.027). Conclusion: PTMC is a safe and effective intervention for severe MS; however, Mitral Annular Calcification significantly reduces procedural success and increases MR risk. Pre-procedural commissural scoring enhances patient selection and outcome prediction. Keywords: Commissural Score, Mitral Annular Calcification, Mitral Regurgitation, Mitral Valve Area, PTMC.