Ensuring durable pulmonary vein isolation for atrial fibrillation: prevention of collateral thermal injury and lesion inconsistency

INTRODUCTION: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation (AF). Despite major technological advances, arrhythmia recurrence remains common because of pulmonary vein reconnection caused by non-durable lesions. Achieving durable PVI requires balancing effective lesion formation with the prevention of collateral injury. AREAS COVERED: This review examines the biophysical determinants of lesion formation, mechanisms responsible for lesion inconsistency, and strategies to improve lesion durability while minimizing collateral injury. The literature was identified through a structured review of major clinical trials, observational studies, mechanistic investigations, and contemporary guideline documents focusing on radiofrequency, cryoballoon, laser balloon, and pulsed field ablation technologies, together with emerging approaches for lesion assessment and procedural optimization. EXPERT OPINION: Durable PVI depends not only on the energy source but also on precise control of catheter - tissue interaction, lesion contiguity, and individualized energy delivery. Pulsed field ablation has substantially improved procedural safety by reducing collateral thermal injury; however, durable lesion formation remains dependent on adequate tissue contact and appropriate energy delivery. Future progress will be driven less by the development of new energy sources than by technologies capable of providing real-time lesion verification and patient-specific ablation strategies.