A 75-year-old female with atrial fibrillation underwent elective left atrial appendage occlusion (LAAO) with a Watchman device. Transseptal access was achieved without complication. A 24 mm device was initially deployed but was later exchanged for a 20 mm device due to excessive device protrusion. Following device implantation, a post-implantation transesophageal echocardiogram (TEE) revealed a periaortic hematoma in the descending thoracic aorta. Subsequent CT angiography confirmed a circumferential hematoma extending from the mid-aortic arch to the descending thoracic aorta. The patient remained hemodynamically stable, reporting only mild back spasms. Anticoagulation was discontinued, and clopidogrel and esmolol were initiated. Given the hematoma’s size and proximity to critical structures, thoracic endovascular aortic repair (TEVAR) was performed on postoperative day 2. The procedure was completed without complications, and the patient remained asymptomatic, medically stable, and was subsequently discharged.