Atrial Fibrillation Ablation in A Patient with Absent Pericardium.

A 45-year-old woman with drug-refractory paroxysmal atrial fibrillation (AF) underwent AF ablation. She had a history of abnormal chest radiograph, which on review was consistent with congenital absence of pericardium and this was later confirmed on cardiac magnetic resonance imaging. She had extreme leftward and posterior rotation of the heart, resulting in abnormal fluoroscopic appearance of the electrophysiological catheters and orientation of the interatrial septum. This along with exaggerated beat to beat motion of the heart posed significant technical challenges for the electrophysiologist during left atrial access and pulmonary vein isolation.