Spontaneous Resolution of a Pseudoaneurysm at the Anastomosis Site of Coronary Artery Bypass Graft: A Case Report

Pseudoaneurysms at the coronary artery bypass graft (CABG) anastomosis site are rare. Here, we report a rare case of spontaneous resolution of a pseudoaneurysm at the anastomosis site developed soon after CABG. A 66-year-old man was referred to our hospital because of chest pain with paroxysmal atrial fibrillation. Pulmonary vein isolation (PVI), atrial appendage closure, and CABG were performed under cardiopulmonary bypass. Contrast computed tomography (CT) on postoperative day (POD) 5 revealed a pseudoaneurysm at the anastomosis of the left internal mammary artery (LIMA) to the circumflex artery. However, the pseudoaneurysm spontaneously resolved after three days. Given the possibility of rupture, surgical or interventional treatment would generally be the first choice. Exceptionally, observation for days to weeks may be one of the management strategies in patients with a small pseudoaneurysm, stable vital signs, no symptoms, discontinuable antithrombotic medications, a short time after CABG, or a pseudoaneurysm at the anastomosis site. The findings in this case may serve as a reference for the determination of treatment strategies for similar cases in the future.