Left atrial and pulmonary vein flutter associated with double electrical connections after a lung transplantation.

A 53-year-old man with a history of a bilateral lung transplantation (LT) at the age of 39 underwent electrophysiological testing of supraventricular tachycardia (SVT). At baseline, the SVT persisted, and exhibited positive P waves in the inferior leads and lead V1. The activation map in the left atrium (LA) revealed a centrifugal pattern from the right pulmonary vein (RPV) cuff ( F1 Panel A). Further mapping within the RPV cuff revealed that the activation propagated from the RPV cuff to the LA through a first conduction gap located at the superior aspect of the RPV cuff and from the LA back to the RPV cuff through a second conduction gap located at the inferior aspect of the RPV cuff (Panel A). It was noted that double potentials or scar were recorded along the presumed suture line between the donor PV cuff and recipient LA (Panel A). These findings suggested that the SVT should be a figure-of-eight type macroreentrant atrial flutter (AFL) associated with two conduction gaps between the donor PV cuff and recipient LA. The results of entrainment pacing from both the anterior and posterior LA wall along the RPV cuff supported this mechanism. A single irrigated radiofrequency application was delivered at the first conduction gap with a fractionated mid-diastolic potential, resulting in a prolongation of the SVT cycle length followed by termination of the SVT (Panel B). A couple of irrigated radiofrequency applications were delivered at the second conduction gap, resulting in the isolation of the RPV cuff. A single electrical connection between the left pulmonary vein cuff and LA was observed at the posterior aspect of their junction, but catheter ablation was not performed at that site.