Abstract Background Mitral valve prolapse (MVP) is a common valvular disorder, affecting approximately 2-3% of the population, with variable outcomes, primarily influenced by mitral regurgitation (MR) severity. However, a subset of patients develops malignant ventricular arrhythmias, independent of MR. The temporal progression of pro-arrhythmic features in MVP remains poorly understood. Purpose To evaluate the long-term structural and electrical remodelling in MVP and identify predictors of arrhythmic and clinical progression. Methods Patients with echocardiographically confirmed MVP who underwent a Holter electrocardiogram (ECG) monitoring within ±9 months and had at least five years of echocardiographic follow-up, were identified from a large tertiary medical center database. A comprehensive manual review of electrocardiographic and echocardiographic parameters was performed at baseline and at last follow-up. The primary endpoint was a composite of sustained or non-sustained ventricular arrhythmia and all-cause mortality. Secondary endpoints included new fulfilment of AMVP diagnostic criteria, progression of MR, changes in mitral annular dimensions, and the prevalence of mitral annular disjunction (MAD) and repolarisation abnormalities. Results Eighty-four patients (39.3% female, mean age 63.7 ± 15.8 years) were included, with a median follow-up of 8.0 years (IQR 6.0-10.0). At baseline, 20.2% met criteria for AMVP and 16.9% had ≥ moderate-to-severe mitral regurgitation (MR). During follow-up, 20 patients died (cumulative incidence of 39.4%) and the 8-year event-free survival for the primary composite of arrhythmic events or death was 49.9% (SE 12.5%). MR severity worsened by ≥1 grade in 34/83 patients (40.5%). Annular remodelling was evident, with increases in mitral annular diameters and MAD length (Δ0.12 ± 0.37 cm). Notably, the prevalence of MAD did not change. QTc prolonged modestly while T-wave inversion rates remained unchanged. In patients with repeat Holters (n = 38), 9/81 patients (11.1%) converted to AMVP. In multivariable analysis, baseline non-sustained ventricular tachycardia (NSVT) was the only independent predictor of the composite arrhythmic or death endpoint (p = 0.003, HR 139, 95% CI 5.6-3440). Conclusions MVP demonstrated progressive structural and electrical changes. A substantial portion of this intermediate-to-high-risk cohort experienced adverse outcomes, underscoring the importance of ongoing clinical, echocardiographic, and electrophysiological surveillance.
Margalit et al. (Mon,) studied this question.