Remote brain hemorrhage after IV thrombolysis: Role of preexisting lesions

Objective To test the hypothesis that remote intracerebral hemorrhages (r-ICHs) after IV thrombolysis occur in preexisting brain lesions. Method We prospectively collected baseline data from consecutive patients treated with IV thrombolysis for cerebral ischemia and reviewed their baseline MRI scans to identify preexisting lesions in those who developed r-ICH. We evaluated outcomes with the modified Rankin Scale (mRS) and defined good outcomes as scores of 0 to 2 or similar to the preexisting mRS score. Results Of 944 patients, 24 (2.5%) had r-ICH: lobar in 14, deep in 7, and both in 3. Sixteen of them (1.7% of all patients, 66.7% of those with r-ICH) were asymptomatic. Of the 41 r-ICHs found in these patients, 17 (41%) occurred within a lesion present before thrombolysis: 6 cerebral microbleeds (CMBs), 6 old and 1 recent infarct, and 4 areas of white matter hyperintensity. Patients with r-ICH were more likely to have strictly lobar CMBs (p = 0.049). They were 10 years older (p = 0.007), had a 16–mm Hg higher systolic blood pressure (p = 0.035) at baseline, and had more CMBs (p = 0.007). r-ICHs were better predicted by clinical (age, baseline systolic blood pressure) than imaging (purely lobar CMBs and having >5 CMBs) variables. r-ICHs tended to be associated with worse outcomes. Conclusion We identified preexisting brain lesions in nearly half of the patients with r-ICH. All were of vascular origin, supporting the hypothesis that r-ICHs occur in preexisting brain lesions. Higher-field machines could help identifying preexisting lesions in those who developed r-ICH in an apparently normal area.