Focal Source of Atrial Fibrillation Arising From the Ostium of the Inferior Vena Cava

Abstract

A patient presented with paroxysmal atrial fibrillation (AF) caused by focal rapid discharges arising from the ostium of the inferior vena cava (IVC). Surface ECG showed typical features of AF and flutter when rapid activation at the IVC ostium was conducted to the right atrium in a 1-to-1 and 2-to-1 fashion, respectively. Discrete radiofrequency energy applications at the medial ostium of the IVC completely eliminated the atrial tachyarrhythmias.