Background
Arrhythmogenic mitral valve prolapse (AMVP) is a cardiac disorder characterized by the coexistence of mitral valve prolapse (MVP) and potentially life-threatening ventricular arrhythmias. The underlying pathophysiological mechanisms as well as the role of surgical valve repair as an antiarrhythmic therapeutic strategy remain poorly understood. This study aimed to evaluate the impact of surgical intervention on arrhythmia burden in patients with AMVP and severe mitral regurgitation.
Methods and Results
Patients diagnosed with MVP between 2010 and 2024 were retrospectively identified from our institutional database. AMVP was defined according to the 2022 EHRA consensus criteria as the presence of MVP accompanied by clinically significant ventricular arrhythmias, in the absence of other structural or ischemic substrates that could explain the arrhythmic phenotype. Pre- and post-surgical data, including follow-up investigations, were analysed. The presence and burden of ventricular arrhythmias were documented before and after surgical intervention. Differences in pre- and post-interventional arrhythmia occurrence were analyzed using Fisher’s exact test.
Among 4708 patients with MVP, 84 (1.8%) met the diagnostic criteria for AMVP. Thirty-six patients (42.8%) were female, and seven (8.3%) exhibited mitral annular disjunction (MAD). The mean left ventricular ejection fraction was 52.3±7.2%. Coronary artery disease was excluded invasively in all patients. Cardiac magnetic resonance imaging was performed in 23 patients (27.4%), of whom 10 (11.9%) demonstrated late gadolinium enhancement in the basal inferolateral segments. During a mean observation period of 2385±1623 days, 68 patients (79.8%) exhibited a significant burden of ventricular extrasystoles (PVC burden >5%). Sixteen patients (19.0%) presented with syncope and 17 patients (20.2%) experienced cardiac arrest due to ventricular fibrillation (VF) or sustained ventricular tachycardia (VT), necessitating cardiopulmonary resuscitation; nine patients received a subcutaneous implantable cardioverter-defibrillator (ICD), and eight individuals received a transvenous ICD.
Surgical mitral valve repair was performed in 64 patients. Minimally invasive reconstruction was conducted in 59/64 patients (92.2%), and valve replacement in 5/64 (7.8%). Syncope occurred in 13/64 patients (20.3%) prior to surgery (Figure 1A). Before surgical intervention, 57/64 patients (89.1%) had a PVC burden >5% (Figure 1B), and ventricular arrhythmias were documented in 14/64 patients (21.9%): 4/64 (6.3%) with non-sustained VT (Figure 1C), 2/64 (3.2%) with sustained VT, and 8/64 (12.5%) with VF (Figure 1D).
During a mean postoperative follow-up of 1690 ± 1254 days, a PVC burden > 5% persisted in 12/64 patients (18.8%) (Figure 1B) (P<0.001). Non-sustained VT was documented in 2/64 cases (3.1%) (Figure 1C), while no patients experienced sustained ventricular arrhythmias or syncope after surgery (Figure 1A, D). Two patients experienced a transient ischemic attack during follow-up.
Conclusion
AMVP represents a rare but clinically significant subtype of MVP associated with malignant ventricular arrhythmias. Surgical mitral valve repair was associated with a significant reduction in PVC burden, syncope, and ventricular arrhythmias, suggesting a potential role in reducing the risk of severe arrhythmic events.
