Abstract
A 47-year-old male with persistent atrial fibrillation presented with melena and presyncope 3 weeks after epicardial ablation and left atrial appendage ligation. He was found to have hemorrhagic pericardial effusion with tamponade physiology and gastrointestinal bleeding from a clean-based duodenal ulcer. Management included pericardiocentesis, anticoagulation reversal, and stabilization. This case underscores the interplay between cardiac tamponade and GI bleeding, highlighting the importance of early recognition and multidisciplinary management.