Abstract 160: Intravenous rt-PA is Not Associated with Increased Risk of Symptomatic Hemorrhage in Patients with Intracranial Aneurysms

Introduction: Recent American Heart Association guidelines for acute ischemic stroke suggest a prominent role for CT angiography. As vascular neuro-imaging is used more commonly in the acute setting, the incidental detection of intracranial aneurysms is likely to increase. In the protocols of some stroke centers, the presence of an intracranial aneurysm is a relative or absolute contraindication for the administration of rt-PA. This study was designed to test the hypothesis that administration of rt-PA is safe in patients who have an unruptured intracranial aneurysm. Methods: We performed a retrospective analysis of all acute ischemic stroke patients treated with rt-PA at our tertiary care academic medical center from June 2006 to June 2010 who also received intracranial vessel imaging during their hospitalization. Patients who received rt-PA but did not receive vessel imaging were excluded. Baseline clinical characteristics were prospectively determined. Identification of hemorrhage and presence of aneurysm was obtained from radiology report and neuro-imaging findings were confirmed by study investigators. Symptomatic ICH (sICH) was defined according to NINDS criteria. Results: Five percent of patients (8/172) had at least one intracranial aneurysm on vessel imaging. There were no differences in baseline clinical characteristics including age, NIHSS, INR, or atrial fibrillation between patients who did and did not have an aneurysm. A total of seven patients (4%) had sICH. There was no significant difference in intracranial aneurysms between patients with or without sICH (1/7 (14%) vs. 7/165 (4.2%), p=0.29). Risk factors for sICH included history of atrial fibrillation (4/7 vs. 31/134, p=0.032; RR = 5.22) and final infarct volume (mean 155 ml 3 (SEM 45) vs. 36 ml 3 (SEM 6); p=0.0004). There was a trend towards increased hemorrhage in patients with elevated serum glucose (mean 153 mg/dl (SEM 19) vs. 123 mg/dl (SEM 4); p=0.068). In the one patient with sICH and an intracranial aneurysm, the location of hemorrhage was distant from the aneurysm. Conclusions: Incidental intracranial aneurysms are common in patients who present with acute ischemic stroke. Administration of rt-PA in these patients appears to be safe, and the presence of an intracranial aneurysm should not be a contraindication to thrombolysis.