Patch Repair for a Subepicardial Aneurysm With an Approach From Inside the Heart

We present a case of subepicardial aneurysm that developed as a complication of acute myocardial infarction. Although the patient had stable hemodynamics, the diameter of the aneurysm tended to increase over time; thus, an operation was performed. We thought that approaching the aneurysm from outside the heart would injure the papillary muscle or distort the left ventricle and exacerbate mitral regurgitation. Therefore, we performed patch repair using bovine pericardium and approached the aneurysm from inside the heart. This is the first case report of a subepicardial aneurysm that was approached and repaired from inside the heart.