B leeding R isk A nalysis in S troke I maging Before Thrombo L ysis (BRASIL)

Abstract

Background and Purpose-There has been speculation that the risk of secondary symptomatic intracranial hemorrhage (SICH) may be increased after thrombolytic therapy in ischemic stroke patients who have cerebral microbleeds (CMBs) on T2*-weighted magnetic resonance imaging. Because of this concern, some centers withhold potentially beneficial thrombolytic therapy from these patients. Methods-We analyzed magnetic resonance imaging data acquired within 6 hours after symptom onset from 570 ischemic stroke patients treated with intravenous tissue plasminogen activator in 13 centers in Europe, North America, and Asia. Baseline T2*-weighted magnetic resonance images were evaluated for the presence of CMBs. The primary end point was SICH, defined as clinical deterioration with an increase in the National Institutes of Health Stroke Scale score by Ն4 points, temporally related to a parenchymal hematoma on follow-up-imaging. Results-A total of 242 CMBs were detected in 86 of 570 patients (15.1%). The number of CMBs ranged from 1 to 77 in the individual patient, with Ն5 CMBs in 6 of 570 patients (1.1%). Proportions of patients with SICH were 5.8% (95% CI, 1.9 to 13.0) in the presence of CMBs and 2.7% (95% CI, 1.4 to 4.5) in patients without CMBs (Pϭ0.170, Fisher's exact test), resulting in no significant absolute increase in the risk of SICH of 3.1% (95% CI, Ϫ2.0 to 8.3). Conclusions-The data suggest that if there is any increased risk of SICH attributable to CMBs, it is likely to be small and unlikely to exceed the benefits of thrombolytic therapy. No reliable conclusion regarding risk in the rare patient with multiple CMBs can be reached.

Silent cerebral microbleeds associated with arterial stiffness in an apparently healthy subject

“…Although several prospective studies have demonstrated that the presence or number of MBs is significantly related to the development of intracerebral hemorrhage in patients with leukoaraiosis and stroke as well as moya-moya disease, 6,37-39 a recent multicenter study demonstrated thrombolysis did not increase the risk of intracerebral hemorrhage in stroke patients with MBs. 40 Although recent guidelines recommend the use of aspirin for the primary prevention of cardiovascular diseases in subjects with high-risk profiles, there is concern that this may facilitate intracerebral hemorrhage in those with MBs. 41 A meta-analysis of primary prevention with a total of 95 456 individuals demonstrated that aspirin increased the risk of intracerebral hemorrhage 1.69 times in men.…”

Use of Magnetic Resonance Imaging to Predict Outcome after Stroke: A Review of Experimental and Clinical Evidence

“…Furthermore, recent evidence suggests that in fact these patients should not be excluded from rtPA treatment. The Bleeding Risk Analysis in Stroke by T 2 *-weighted Imaging before thromboLysis study revealed no increased risk of SICH from thrombolysis (Fiehler et al, 2007). In a recent study, fluid attenuation inversion recovery images were able to delineate focal regions of hyperintensity before thrombolysis that were highly correlated with increased risk of SICH (Cho et al, 2008) and could thus be used as an attractive SICH predictor.…”

Stroke occurring in patients with cognitive impairment or dementia

“…Leukoaraiosis has been reported as a risk for haemorrhagic transformation after rt-PA 43 . Cerebral microbleeds 44 and small-vessel disease 45 are also markers of increased risks for haemorrhagic transformation. However other studies have shown that this effect is modest and should not prevent the administration of rt-PA 46 .…”