Reappraising Use of Flecainide for Atrial Fibrillation and Ventricular Arrhythmias in Structural Heart Disease Patients

<i>Background</i>: Flecainide, a class Ic antiarrhythmic agent, has long been contraindicated in structural heart disease (SHD) due to findings of the Cardiac Arrhythmia Suppression Trial (CAST). However, its proven efficacy in patients without structural abnormalities and emerging safety data in selected SHD populations have prompted reconsideration of its role. <i>Aim</i>: This mini review evaluates recent evidence on the safety and efficacy of flecainide in atrial fibrillation (AF) and premature ventricular contractions (PVCs), particularly in patients with stable coronary artery disease (CAD), and arrhythmogenic right ventricular cardiomyopathy (ARVC). <i>Results</i>: Modern imaging and improved risk stratification allow for more precise identification of patients who may safely receive flecainide, even in the presence of specific structural abnormalities. Observational studies have reported no mortality or ventricular arrhythmias incidence increase in stable CAD or ARVC when flecainide is administered under stringent criteria. While current guidelines remain cautious, clinical practice is beginning to reflect a more individualized approach. <i>Conclusions</i>: Flecainide use in selected SHD patients appears both feasible and safe when guided by comprehensive imaging and clinical judgment. The need for prospective randomized trials to confirm these findings and potentially inform future guideline updates is urgent and of utmost importance in the field of antiarrhythmic therapies.