Detection of a unidirectional epicardial connection between the right-sided pulmonary venous carina and the right atrium by pacing from a high-density mapping catheter.

We report a case of recurring, persistent atrial fibrillation (AF) in a patient with a unidirectional epicardial connection (EC) between the right-sided pulmonary venous (PV) carina and the right atrium detected using a high-density mapping catheter with a steerable introducer support, but not a conventional circular mapping catheter. This unidirectional EC could be steadily abolished by a radiofrequency delivery. Finally, we were able to successfully achieve complete PV antrum isolation. Thereafter, he has remained well without any AF.