Treatment of ruptured subclavian steal flow-related vertebrobasilar junction aneurysms: Case report on surgical and endovascular considerations from two cases.

Introduction: Subclavian steal phenomenon causes retrograde flow through the vertebral artery, ipsilateral to the affected subclavian artery, which rarely leads to flow-related vertebrobasilar junction (VBJ) aneurysms.

Case Descriptions: We describe two cases of subarachnoid hemorrhage from such ruptured aneurysms in which the retrograde flow direction in the vertebral artery complicated surgical and endovascular treatment.

Discussion: Reversed flow in the vertebral artery, ipsilateral to the stenotic subclavian artery leads to a lack of proximal control in surgical clipping of these VBJ aneurysms and jeopardizes stability of coil and stent placement in endovascular aneurysm treatments in this setting.