Redo Scoring for Prediction of Success of Redo-Percutaneous Balloon Mitral Valvuloplasty in Patients with Mitral Restenosis.

Background: Echocardiographic predictors of redo-percutaneous balloon mitral valvuloplasty (redo-PBMV) have not been well studied, and indications are based mainly on Wilkins score. The study aim was to evaluate the immediate results of redo-PMBV and to introduce a simplified redo-score to predict the success of redo-PBMV.

Methods: Two cohorts of symptomatic patients (derivation group, n = 218; validation group, n = 100) who had undergone redo-PBMV at a mean of 8.1 ± 2.9 years after a first successful PBMV were enrolled in the study. The mean Wilkins scores were 8.5 ± 1.7 in the derivation group and 8.4 ± 1.8 in the validation group. PBMV was performed using a multi-track technique. Independent echocardiographic predictors of outcome were assigned a points value: mitral valve area ≤1.0 cm2 (2 points), posterior mitral valve leaflet length (PMVL)/anterior mitral valve leaflet length (AMVL) ratio ≤1/2 (2 points), doming distance ≤12 mm (3 points), mitral annular calcification (mild = 1 point; moderate = 2 points; severe = 3 points), commissural status (no fusion = 0 points; uni-fusion = 2 points; bi-fusion = 3 points) and chordal length ≤10 mm (2 points).

Results: The minimum score was 5 and the maximum was 13. A receiver operating curve analysis showed the redo score to be highly significant in predicting redo-PBMV immediate results. The cut-off value of redo score to predict a favorable outcome was ≤8, with a sensitivity of 96% and specificity of 85% in the derivation cohort, and a sensitivity of 95% and specificity of 83% in the validation cohort. A Wilkins score ≤8 had a sensitivity of 71% and a specificity of 59% in the derivation cohort, while sensitivity was 70% and specificity 62% in the validation cohort.

Conclusions: The described scoring system was significantly more predictive than the Wilkins score, and was particularly valuable in predicting outcome in patients with a prior PBMV. It may serve as a satisfactory scoring system for correctly selecting patients with mitral restenosis for PBMV.