Intraprocedural thrombus formation in a patient with anticoagulated atrial fibrillation

A 57-year-old man with 16-year history of persistent atrial fibrillation (AF) was admitted for electrophysiology study and catheter ablation. He was on amiodarone, carvedilol and warfarin. His international normalised ratio (INR) was 2.2. Intracardiac echocardiogram (ICE) prior to atrial septum puncture did not show any spontaneous echo contrast. After advancing the sheath across the interatrial septum, it was flushed with heparin. A few seconds after sheath placement and prior to placement of …