In this EP Edge and Heart Rhythm Society collaborative podcast, Dr. Niraj Sharma and Dr. Mike Lloyd examine new evidence challenging several long-standing assumptions in cardiac electrophysiology: when to choose catheter ablation over antiarrhythmic drug therapy for atrial fibrillation, whether left bundle branch area pacing should replace conventional right ventricular pacing in patients who require substantial ventricular pacing, and how broadly the lessons of CAST should continue to restrict flecainide and other Class Ic antiarrhythmic drugs.
The atrial fibrillation discussion brings together two complementary 2026 Heart Rhythm meta-analyses. Demy L. Idema and colleagues evaluated antiarrhythmic drugs versus catheter ablation for rhythm control across randomized controlled trials, focusing on AF recurrence, hospitalization, mortality, and treatment-related complications. Marwan Shawki and colleagues examined the safety of catheter ablation versus antiarrhythmic drugs across 24 randomized trials involving 6,665 participants. Together, the studies raise an important contemporary question: as ablation becomes more effective and procedural safety improves, does antiarrhythmic drug therapy still deserve an automatic position ahead of ablation in the AF treatment pathway?
The discussion then turns to physiologic pacing and the PACE-HF trial by Jenish P. Shroff and colleagues, published in the European Heart Journal. In this prospective randomized trial, left bundle branch area pacing was compared with conventional right ventricular pacing in patients with preserved or mildly reduced left ventricular ejection fraction who were expected to require substantial ventricular pacing. The trial provides randomized evidence on ventricular function, pacing burden, heart failure hospitalization, and the potential consequences of chronic nonphysiologic right ventricular activation.
Finally, the podcast revisits flecainide more than three decades after the Cardiac Arrhythmia Suppression Trial (CAST). The discussion incorporates the systematic review by Li and colleagues in Heart Rhythm examining how CAST reshaped flecainide research and clinical use, together with the nationwide cohort study by T.-C. Huang and colleagues in Heart Rhythm evaluating Class Ic antiarrhythmic therapy after PCI in patients with new-onset atrial fibrillation. The central question is not whether CAST was correct in the post-myocardial-infarction population it studied, but whether its findings have been extrapolated too broadly to contemporary patients with stable or revascularized coronary disease, preserved ventricular function, and atrial rather than ventricular arrhythmias.
Across atrial fibrillation ablation, conduction-system pacing, and Class Ic antiarrhythmic therapy, the episode asks a common question: when new evidence challenges an established electrophysiology default, when is the evidence strong enough to change everyday practice?
Idema DL, et al. Antiarrhythmic drugs vs catheter ablation as rhythm control for atrial fibrillation: A systematic review and meta-analysis of randomized controlled trials. Heart Rhythm. 2026;23:1465-1475.
Shawki M, et al. Safety of catheter ablation compared with antiarrhythmic drugs for atrial fibrillation: A systematic review and meta-analysis of randomized trials. Heart Rhythm. 2026;23:1453-1464.
Shroff JP, et al. Left bundle branch area pacing vs right ventricular pacing in preserved or mildly reduced ejection fraction: the PACE-HF trial. European Heart Journal. 2026;47:3298-3300.
Li et al. Flecainide use before and after the Cardiac Arrhythmia Suppression Trial: A systematic review. Heart Rhythm. 2026.
Huang TC, et al. Class Ic antiarrhythmic therapy after PCI in new-onset atrial fibrillation: Safety and clinical outcomes from a nationwide cohort. Heart Rhythm. 2026;23:e1372-e1382.