A 49-year-old obese female was admitted for acute onset pleuritic chest pain. Previous history was significant for surgical correction of a lower esophageal ring. Echocardiography revealed a pericardial effusion, which resolved with steroids. One week later, the patient complained of similar symptoms. Physical examination was consistent with tamponade, while a Hammond crunch was noted over the sternum. Chest x-ray revealed a pneumopericardium. Operative findings consisted of an intrathoracic stomach, a greater curvature ulcer that had perforated the pericardium and a mediastinal abscess. A pericardial window was created, a drain was placed and the perforated ulcer was repaired. Postoperative course was complicated by fever and gastrointestinal bleeding. The patient died suddenly on the 30th postoperative day. Autopsy revealed a massive pulmonary embolus, bleeding esophageal ulcer, healed gastric ulcer and serofibrinous pericarditis. This case illustrates that, while the immediate treatment of tension pyopneumopericardium is usually successful, postoperative mortality remains elevated.