Endovascular Repair of an Extracranial Internal Carotid Artery Aneurysm Complicated by Heparin-Induced Thrombocytopenia and Thrombosis

Abstract

Purpose: To report the endovascular treatment of a symptomatic extracranial internal carotid artery (ICA) aneurysm that was complicated by heparin-induced thrombocytopenia and thrombosis. Methods and Results: After undergoing a coronary artery bypass graft procedure, a patient was diagnosed with a symptomatic, 3.5-cm ICA aneurysm by computed tomography and angiography. Via a semiclosed access, an Enduring vascular graft was inserted under controlled back bleeding from the ICA. The patient was recovering uneventfully when routine duplex scanning on the fifth postoperative day suggested multiple thrombi within the graft, which was confirmed by arteriography. Thrombectomy and local fibrinolysis were performed; however, the graft occluded the next day without causing neurological symptoms. Heparin-induced thrombocytopenia was diagnosed by enzyme-linked immunosorbent assay. Conclusions: Endovascular repair of high cervical extracranial ICA aneurysms is feasible, and protection against intracerebral embolization can be achieved using a semiclosed technique with controlled back bleeding from the ICA during endograft deployment. However, multiple thrombi or thrombotic occlusion during the postoperative period, particularly in a patient already sensitized to heparin, should direct attention toward possible heparin-induced thrombocytopenia.