Catheter ablation of atrial tachycardia due to recipient-to-donor transatrial conduction after orthotopic heart transplantation.

Atrial arrhythmias occur frequently after orthotopic heart transplantation. In some cases, they may depend on atrio-atrial conduction across the surgical suture line. We report an unusual case of a heart transplant recipient who had recipient atypical atrial flutter with 2:1 transatrial conduction and a resulting tachycardia in the donor atrium. Electroanatomical mapping identified the site of transatrial conduction and guided successful catheter ablation.