Incidence and type of recurrent ventricular arrhythmia in patients with arrhythmic mitral valve prolapse and implantable cardioverter defibrillator for secondary prevention

Abstract

Aims: Mitral valve prolapse (MVP) is a common valvular disorder associated with ventricular arrhythmias (VAs) in a subgroup of patients, known as arrhythmic MVP (AMVP). Arrhythmic MVP patients with malignant VAs typically receive an implantable cardioverter-defibrillator (ICD) for secondary prevention. However, data regarding the incidence of appropriate ICD therapy and the type of arrhythmia recurrence in this population remain scarce. This study aimed to evaluate the incidence of appropriate ICD therapies and type of arrhythmia recurrence in AMVP patients with an ICD implanted for secondary prevention. Methods and results: A systematic literature search was conducted in PubMed/MEDLINE and EMBASE databases until January 2025. Studies reporting the incidence of appropriate ICD therapy in AMVP patients were included. A total of 9 studies met the inclusion criteria, resulting in 166 AMVP patients with ICDs for secondary prevention. The mean age was 41.8 years, with 55.8% of patients being female. Over a weighted mean follow-up of 4.9 ± 3.1 years, 34.9% [95% confidence interval (CI): 28.1–42.5] of the patients experienced recurrence of VA. The pooled incidence of appropriate ICD therapies during follow-up was 8.1 per 100 person-years (95% CI: 5.6–10.5, I2: 11.7%). Regarding the type of arrhythmic recurrence, the majority of arrhythmias (53.8%, 95% CI: 44.3–63.0%) were in the form of ventricular fibrillation or polymorphic ventricular tachycardia (VT), while the remaining arrhythmias were reported as monomorphic VT. Among 67 ventricular arrhythmic episodes reported in 7 studies with available data, 65 required shock therapy, corresponding to a shock proportion of 97.0% (95% CI: 89.6–99.6%). Conclusion: Arrhythmic MVP patients with ICDs for secondary prevention exhibit a high risk of recurrent arrhythmias, with recurrences in the form of polymorphic VA occurring in more than half of the cases.