A variant of pulmonary vein-gap reentrant atrial tachycardia with multiple epicardial conduction gaps

Abstract

A 66-year-old male had an atrial tachycardia (AT) during a first extensive pulmonary vein (PV) isolation (PVI) of persistent atrial fibrillation. Activation mapping during the AT using Rhythmia (Boston Scientific, Marlborough, MA, USA) exhibited a centrifugal pattern with the earliest activation at the left-sided carina, and conduction towards the inferior left atrium (LA) over the left PVI line. The post-pacing interval was similar to the tachycardia cycle length (TCL) upon entrainment from the LA roof, left-sided carina, and anterior, inferior, and septal LA, but was longer than the TCL upon entrainment from the left superior PV and lateral and posterior LA. These findings suggested the presence of a macroreentrant AT circuit with epicardial conduction from the roof toward the inferior LA via the left-sided carina over the PVI line and propagation to the anterior LA through the septum. A radiofrequency application at the left-sided carina terminated the AT. This case suggested a rare type of PV-gap reentrant AT with multiple epicardial conduction gaps by high-resolution activation mapping and entrainment pacing, which may have been associated with non-transmural radiofrequency lesions along the PVI line. Further, the origin of the residual epicardial gaps may have been subepicardial myocardial strands or the Marshall ligament.<Learning objective: Pulmonary vein (PV)-gap reentrant atrial tachycardias (ATs) generally have conduction gaps on the previous PV isolation lines. However, this case had a variant of PV-gap reentrant AT with multiple epicardial conduction gaps, without any endocardial gaps on the PV isolation line. High-resolution activation mapping during PV pacing and the AT in combination with entrainment pacing may facilitate an identification of residual epicardial connections associated with the PV-gap reentrant AT circuits.>