Hybrid ablation for atrial fibrillation: the importance of achieving transmurality and lesion validation

Therapeutic ablation for atrial fibrillation (AF) has evolved significantly with progressive advancements in technology and surgical instruments. With the goal of minimizing surgical morbidity while maintaining the benefits of the traditional Cox-Maze procedure, surgical ablation for AF has undergone significant modifications. Most recently, an increased understanding of substrate complexity, predominantly in patients with persistent or long-standing persistent AF, has led to the development of a synergistic hybrid approach. The hybrid approach attempts to combine the benefits of epicardial ablation and catheter-based endocardial ablation in order to overcome the shortcomings associated with each technique alone. Importantly, the aid of electrophysiological intervention has provided new opportunities for evaluating lesion transmurality both acutely and in a staged approach. Therefore, the hybrid procedure may provide the optimal approach for the surgical treatment of AF, with the potential to tailor procedural treatment according to the patient's specific needs. In this review, we aim to provide an overview of current surgical techniques, including the implications of this novel hybrid approach in the management of AF and improving procedural outcomes. Recent findings from published studies are highlighted with a primary focus on the importance of lesion transmurality and validation in a hybrid setting.