Endovascular repair of an extracranial internal carotid artery aneurysm complicated by heparin-induced thrombocytopenia and thrombosis

Purpose: To report the endovascular treatment of a symptomatic extracranial internal carotid artery (ICA) aneurysm that was complicated by heparin-ind uced thrombocytopenia and thrombosis. Methods and Results: After undergoing a coronary artery bypass graft proced ure, a patient was diagnosed with a symptomatic, 3.5-cm ICA aneurysm by com puted tomography and angiography. Via a semiclosed access, an Enduring vasc ular graft was inserted under controlled back bleeding from the ICA. The pa tient was recovering uneventfully when routine duplex scanning on the fifth postoperative day suggested multiple thrombi within the graft, which was c onfirmed by arteriography. Thrombectomy and local fibrinolysis were per for med; however, the graft occluded the next day without causing neurological symptoms. Heparin-induced thrombocytopenia was diagnosed by enzyme-linked i mmunosorbent assay. Conclusions: Endovascular repair of high cervical extracranial ICA aneurysm s is feasible, and protection against intracerebral embolization can be ach ieved using a semiclosed technique with controlled back bleeding from the I CA during endograft deployment. However, multiple thrombi or thrombotic occ lusion during the postoperative period, particularly in a patient already s ensitized to heparin, should direct attention toward possible heparin induc ed thrombocytopenia.