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Substrate Ablation in Treatment of Atrial Fibrillation

From the time catheter ablation of atrial fibrillation (AF) was first reported, of the two dominant approaches for AF ablation, only pulmonary vein (PV) isolation has been modified, while circumferential pulmonary vein ablation (CPVA) as performed by our group in Milan has remained substantially unmodified. In fact, PV isolation as initially performed by Haissaguerre et al. has undergone rapid evolution toward substrate modification with significantly higher success rates without major complications. Modification of such technique was due to modification of the substrate. It is now evident that substrate modification is indeed crucial for curing AF particularly in patients with long‐lasting or permanent AF. Indeed, to achieve good outcomes, any ablation technique should simultaneously include elimination of all triggers associated with modification of both anatomic and autonomic substrate, as we started to do many years ago by performing CPVA.