Persistent tachycardia originating from the superior vena cava as a driver for atrial fibrillation.

We describe a patient with drug-resistant paroxysmal atrial fibrillation who underwent radiofrequency catheter ablation of tachycardia originating from the superior vena cava (SVC). A continuous and rapid tachycardia conducted to the atrium with evidence of exit block and drove atrial fibrillation (AF) and atrial tachycardia. Neither AF nor atrial tachycardia could be induced after SVC isolation, and nor were they observed during follow-up. We conclude that continuous and rapid tachycardia originating from the SVC can act as a driver as well as an initiator of AF.