Penetration of the pericardium and heart by benign peptic ulcers is rare. Before 1965 it was almost invariably fatal, but about 20% of recently reported cases have survived. We report 4 representative cases and review 91 additional cases from the literature. The ulcers arose in esophagus, hiatus hernias, abdominal stomach, and near anastomoses, and the predominant predisposing factor was previous surgery to the esophagogastric region. Whereas penetrating esophageal ulcers had a slightly better prognosis than gastric lesions, the principal determinant of clinical presentation, findings, and prognosis was the site of cardiac involvement. The clinicopathological features of pericardial, atrial, and ventricular involvement are distinct. We evaluate the different implications of these features for diagnosis, management, and prognosis and make some tentative recommendations regarding diagnostic procedures and treatment. Early diagnosis and prompt surgical intervention are critical to successful treatment of this entity, which may present with predominantly cardiac or gastrointestinal symptomatology.