Coronary sinus focus acting as a trigger for atrial fibrillation in a patient with orthotopic heart transplantation

Coronary Sinus Focus Acting as a Trigger for Atrial Fibrillation. We report the case of a 46-year-old man who presented for evaluation and ablation of paroxysmal atrial fibrillation, which he developed one year prior to presentation and that was refractory to antiarrhythmic drugs. His past medical and surgical history was significant for orthotopic heart transplantation (OHTX) and idiopathic nonfamilial dilated cardiomyopathy. We present the first case of post OHTX where the coronary sinus was acting as a trigger and driver for atrial fibrillation. This illustrates an unusual role of nonpulmonary vein foci in the etiology of atrial fibrillation in patients status post OHTX.