Efficacy of flecainide in patients with premature ventricular contractions-induced cardiomyopathy: Subanalysis of the UNIFLECA study

Abstract Background Persistent high burden of Premature ventricular contractions (PVCs) (10%) may lead to PVC-induced cardiomyopathy, a reversible form of left ventricular (LV) dysfunction. Flecainide may offer therapeutic benefit in this patients declining catheter ablation. Purpose To investigate the effect of flecainide on left ventricular systolic function in patients with PVC-induced cardiomyopathy, defined as a left ventricular ejection fraction (LVEF) 50%, within the framework of the UNIFLECA study. Methods A subanalysis was conducted among patients presenting with LVEF 50% at baseline. LVEF values were compared between the screening period and the 3-month follow-up under flecainide therapy using paired observations and a paired t-test. Coronary artery disease was systematically excluded by invasive or non-invasive methods, and cardiac magnetic resonance imaging (CMR) was performed to confirm the absence of underlying structural cardiomyopathy or myocardial scar, thereby supporting a definitive diagnosis of PVC-induced cardiomyopathy. Results Out of the 82 patients in the UNIFLECA cohort, ten (n=10, 12.19%) had reduced LVEF (50%) at baseline. In all cases, coronary artery disease was excluded either invasively or non-invasively, and CMR confirmed the absence of structural abnormalities or myocardial scarring, validating the diagnosis of PVC-induced cardiomyopathy. The mean baseline LVEF was 42.1% ± 5.4%, indicating mild to moderate systolic dysfunction. After three months of flecainide therapy, LVEF increased significantly to 54.7% ± 4.3% (p = 0.011). All patients demonstrated improvement in systolic function, documenting the reversibility of PVC-induced cardiomyopathy following effective antiarrhythmic therapy. Conclusions Flecainide was associated with significant recovery of left ventricular ejection fraction in patients with PVC-induced cardiomyopathy (LVEF 50%). These findings highlight flecainide as a safe and effective therapeutic option for patients with mild-to-moderate systolic dysfunction secondary to high-burden PVCs that decline catheter ablation.EF Response in PVC induced CMP