Spontaneous Aortic Arch Thrombus Presenting as Acute Critical Limb Ischemia

We report a case of a 52-year-old male who presented with acute leg ischemia and underwent successful femoral embolectomy and fasciotomies. Investigations revealed a pedunculated mass in the aortic arch, floating under the innominate and left common carotid arteries. Urgent resection was performed through a longitudinal aortotomy with deep hypothermic circulatory arrest and axillary artery perfusion to reveal a 2.5 × 1.5 cm pedunculated mass attached to the posterior aspect of the arch that was resected. Histology revealed thrombus material prompting lifelong systemic anticoagulation. On 3 months follow-up, the patient had returned to normal activities and computed tomography confirmed complete resection without recurrence. This case study demonstrates that spontaneous thrombus formation is possible in high-flow vascular regions such as the aortic arch and also confirms the importance of evaluating central sources of thromboemboli in patients presenting with acute limb ischemia. Urgent surgical removal is recommended and can be performed safely.