Impact of cerebral microbleeds on bleeding and outcome after stroke thrombolysis

Cerebral microbleeds may be responsible for bleeding and poor functional outcome following thrombolysis of acute ischemic stroke. We tried to assess the association between cerebral microbleeds, hemorrhagic complication and functional outcome following intravenous thrombolysis in Egyptian acute ischemic stroke patients. We evaluated 66 acute ischemic stroke patients treated with intravenous thrombolysis for cerebral microbleeds using T2* weighted Magnetic Resonance Imaging Gradient echo. Distribution, number, and predictors of microbleeds were assessed. The effect of microbleeds presence and burden on development of hemorrhage after thrombolysis and 90 days functional outcome was evaluated. Out of 66 stroke patients treated with intravenous thrombolysis, 33 patients had microbleeds. Multivariate analysis shows that hypertension, diabetes mellitus, atrial fibrillation, smoking and leukoaraiosis were independently associated with microbleeds. Post-thrombolysis symptomatic intracerebral hemorrhage occurred in 12/66 (18.1%). Multivariate analysis shows that high burden microbleeds (≥ 10), leukoaraiosis, stroke severity, delayed thrombolysis were independently associated with intracerebral hemorrhage. Post-thrombolysis hemorrhage was statistically higher in microbleeds group (51.5%) than non-microbleeds group (9.1%) (p < 0.001). Parenchymal hemorrhage represents (58.8%) of hemorrhagic cases in microbleeds group in comparison to (33.3%) of non-microbleeds group (p = 0.62). Parenchymal hemorrhage represents (50%) of hemorrhagic cases with microbleeds < 10, while it represents (100%) of hemorrhagic cases with microbleeds ≥ 10. Favorable modified Rankin Scale (0–2) was more prevalent in non-microbleeds group (72.7%) than microbleeds group (45.5%) at 90 days (p = 0.024). Favorable outcome at discharge and at 90 days was statistically more prevalent in patients with microbleeds < 10 (p = 0.004). High burden cerebral microbleeds should be considered a risk for parenchymal hemorrhage following intravenous thrombolysis. The presence and burden of microbleeds may affect prognosis 90 days after thrombolytic therapy.