INTRODUCTION
The advent of high-density mapping has considerably facilitated the diagnosis and treatment of atrial tachycardia (AT). Macroreentrant circuit and bursting focus are at both ends of the mechanistic spectrum and thus necessitate opposite ablation strategies. Perimitral, roof-dependent, and cavotricuspid isthmus (CTI)-dependent flutters can be efficiently treated with a linear lesion blocking an anatomical isthmus. Whereas focal ATs require a patchy lesion targeting the source, which most often corresponds to the earliest electrical activity. At the crossroads has recently emerged a category of AT showing centrifugal propagation, while the underlying mechanism is, in fact, macroreentry.1 This comes along with a better understanding of the key role of distinct atrial epicardial structures.2 Identifying these ”pseudo-focal” ATs is crucial in order to opt for the appropriate ablation strategy.
The present study is a retrospective analysis of pseudo-focal ATs, with specific emphasis on the anatomical substrates, electrophysiological properties, and ablation outcomes.