All experts involved in the development of these guidelines have submitted declarations of interest. These have been compiled in a report and published in a supplementary document simultaneously to the guidelines. The report is also available on the ESC website www.escardio.org/Guidelines See the European Heart Journal online for supplementary data that includes background information and detailed discussion of the data that have provided the basis of the guidelines.Click here to access the corresponding ESC CardioMed chapters.

Treatment options for atrial fibrillation (AF) have evolved from simple, fluoroscopy-guided pulmonary vein isolation for those patients with paroxysmal AF to complex, multi-modality procedures targeting not only anatomic structures but also electrophysiologic phenomena including complex fractionated electrograms, sites of dominant frequency and local non-venous drivers in patients with persistent and permanent AF. The stepwise ablation approach is a novel technique whereby structures contributing to initiation and maintenance of AF are sequentially targeted by radiofrequency ablation. Broadly divided into pulmonary veins, left atrial (LA) roof, left atrium (incorporating all anatomic regions of the chamber), mitral isthmus and non-LA structures, each region is targeted in sequence and the impact of ablation upon the global fibrillatory process assessed by measurement of AF cycle length (AFCL) at a site remote from the ablation target. In addition to pulmonary vein electrical disconnection and demonstrable complete conduction block across the roof and mitral isthmus lines (when performed), ablation is performed at those sites displaying continuous electrical and complex fractionated activity, with the endpoint of local organization, as well as at sites displaying electrograms consistent with focal sources driving AF. Ablation is accompanied by a cumulative increase in the AFCL prior to termination of AF by conversion either directly to sinus rhythm or to an atrial tachycardia which is then mapped conventionally and ablated. There is a ceiling of ablation within the LA beyond which further ablation is unlikely to result in a clinical benefit and should prompt evaluation of the contribution of the right atrium to maintenance of AF. The stepwise approach benefits from the integration of anatomic and electrophysiologic information to achieve a high level of success in termination of chronic AF by catheter ablation.

AMSA has the potential for guiding more optimal timing of defibrillation without adverse interruption of cardiopulmonary resuscitation or the delivery of unsuccessful high energy electrical shocks that contribute to postresuscitation myocardial injury.

Catheter ablation targeting both the endocardial and epicardial aspects of the CS region significantly prolongs fibrillatory cycle length and terminates AF persisting after PV isolation in 35% of patients.