Background In cases of subarachnoid hemorrhage due to aneurysm rupture, the administration of an anticoagulant or antiplatelet agent involves the risk of rebleeding from the aneurysm. There is a possibility of inducing thromboembolic events during the endovascular embolization of ruptured cerebral aneurysms. Patients and methods From April 2006 to March 2017, we treated a total of 70 patients with ruptured cerebral aneurysms with an endovascular technique. Among them, five patients (7.1%) showed intra-arterial thrombus formation. The aneurysms were located at the anterior communicating artery and basilar artery in two patients each, and on the internal carotid artery at the bifurcation of the anterior choroidal artery (AChoA) in one. In these patients, the clinical course, radiological findings, and management were retrospectively reviewed. Results Thrombus formation was observed in the posterior cerebral artery, anterior cerebral artery (A2), AChoA, and middle cerebral artery. The timing of thrombus formation was during coil delivery in four cases, and guiding catheter advancement in one. As for thrombus management, for all patients, administrations of heparin and antiplatelet agents were performed. For four patients, urokinase injection into the affected arteries was added after the completion of embolization. Cerebral infarction was postoperatively identified in two patients, but no hemorrhage was noted. Conclusion Administrations of heparin and antiplatelet drugs should be performed appropriately during procedures, and close observation of the arterial condition on angiography is necessary. Once thromboembolism occurs during the endovascular embolization of ruptured cerebral aneurysms, adequate heparinization, and antiplatelet therapy should first be performed.
Keywords: Ruptured; cerebral aneurysm; endovascular treatment; thromboembolism.