Vertebral Artery Sacrifice After Balloon Test Occlusion in Endovascular Repair of Subclavian Artery Aneurysm

Introduction: Isolated true subclavian artery aneurysm (SAA) is a rare form of peripheral arterial aneurysm that poses significant anatomical challenges to endovascular repair, especially in cases requiring planned vertebral artery (VA) sacrifice. The Balloon Occlusion Test (BOT) is a critical preoperative tool for evaluating collateral circulation before VA embolization. Case Report: A 74-year-old male was admitted with a pulsatile mass in the left supraclavicular fossa, and a 65 mm aneurysm of the intrathoracic segment of the left subclavian artery (LSA) involving critical arterial branches was diagnosed by computed tomography angiography. Due to his comorbidities, the patient was judged unfit for an open surgical repair of the aneurysm, and a two-stage endovascular subclavian aneurysm repair (EVSAR) was planned. The first step included embolization of the internal mammary artery and thyrocervical trunk, followed by BOT of the left VA, which confirmed an adequate perfusion of the posterior cerebral and cerebellar circulation that allowed safe VA embolization. The second step included zone 2 thoracic endograft placement (TEVAR) with LSA coverage and vascular plug occlusion of the proximal segment of the LSA and the axillary artery. Postoperative monitoring revealed no neurological deficit, and the patient was discharged home without complications. Follow-up imaging up to 24 months confirmed complete aneurysm exclusion and significant sac shrinkage. Conclusions: EVSAR with thoracic endograft and VA sacrifice, preceded by BOT, may be a safe and effective minimally invasive approach for the treatment of intrathoracic SAA.