CMR-Based Prediction of Arrhythmic Risk in Mitral Valve Prolapse
Author Block: Y. B. Uluman, E. İsmailov, F. Köse, M. Kadıoğlu, B. Tütüncüoğlu, F. Alpaslan, T. Banaz, K. B. Bekaroğlu, S. Baş Özkök; Istanbul/TR
Purpose: To investigate the association between cardiac arrhythmias and cardiac magnetic resonance (CMR) findings in mitral valve prolapse (MVP).
Methods or Background: MVP is usually benign, but some patients develop malignant arrhythmias and sudden cardiac death; CMR may help identify structural risk markers.
We retrospectively analyzed 27 MVP patients underwent 1.5 Tesla CMR with cine, T1/T2 mapping, and late-gadolinium-enhancement (LGE). Assessed parameters included ventricular volume/function, prolapse height, valve thickening, mitral annular disjunction, and LGE extent/localization. Prolapse height was defined relative to the atrioventricular junction, and measurements were performed using automated segmentation with manual correction. ECG/Holter were used to assessed arrhythmia. Continuous variables were presented as mean±SD and compared with the Mann–Whitney U test; categorical variables with the chi-square test. Correlations were examined using Pearson or Spearman coefficients, and multivariate logistic regression identified independent arrhythmia predictors. Significance was set at p<0.05.
Results or Findings: Mean prolapse height was 9.3±3.0 mm, and valve thickening was present in 29.6% of patients. MAD was identified in 66.7% (true/pseudo ratio: 11/8). Arrhythmia occurred in 44.4%, while biventricular systolic function was preserved. LGE was observed in 81.5% of patients, mostly limited (<5% of myocardial volume in 86.4%), involving the inferolateral wall in 29.6% and papillary muscles in 18.5%. Documented arrhythmias includes ventricular extrasystole (n=5), atrial fibrillation (n=2), and sustained ventricular tachycardia (n=5); no sudden death occurred. LGE extent and inferolateral wall involvement were not associated with arrhythmia, whereas papillary muscle fibrosis showed a significant correlation (OR=31.1,p=0.02,AUC=0.89).
Conclusion: This study demonstrated that papillary muscle fibrosis is a strong independent predictor of arrhythmia in patients with mitral valve prolapse. The findings suggest that papillary involvement, rather than global myocardial fibrosis, may represent the key structural substrate for arrhythmogenesis in this population.
Limitations: Relatively small, single-centre sample size.
Funding for this study: N/A
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Number: E-96317027-514.10-251444224 Subject: KAEK/26.06.2024.70