A 79-year-old man died 3.5 hours after catheter ablation of atrial fibrillation due to pericardial tamponade. Autopsy and consecutive microscopic examinations furnished evidence of electrothermical necroses topographically arranged regularly adjacent to the pulmonary veins in the left atrium and across the area of the isthmus in the right atrium with a rupture of the right atrial wall in the area of a coagulation spot. The post-mortem findings and pathogenetic considerations for the delayed pericardial tamponade are discussed.
