Hemorrhagic Moyamoya Angiopathy in European Patients

BACKGROUND: Moyamoya angiopathy (MMA) is an important cause of juvenile stroke but an overall rare disease among European populations compared with East Asian cohorts. Consecutively, hemorrhagic MMA is described well in East Asian cohorts, but knowledge in non-Asian patients is limited. Literature suggests that disease presentation may vary between those cohorts, also including hemorrhage frequencies. Hence, this article aims to analyze hemorrhagic MMA in European patients. METHODS: We screened for patients of European origin with MMA from a single-center consecutive database of a German hospital specialized on MMA. Those who had a record of intracranial hemorrhage were analyzed individually regarding the type of hemorrhage and use of antiplatelet therapy before and after bleeding onset. To identify associated factors of intracranial hemorrhage, an age- and sex-matched control group was identified from the pool of patients without a history of hemorrhage. Both groups had a comparable follow-up time and were compared in terms of disease presentation, therapeutic interventions, and imaging characteristics, using both univariate tests and multivariate logistic regression analysis. RESULTS: From a pool of 332 patients with MMA we identified 288 of European ancestry. From those, 36 had a record of intracranial hemorrhage (12.5%). Thirty-three patients presenting with 37 events were included for further analysis and case-control-comparison. Most events were intracerebral hemorrhage (n=20; 54%) and subarachnoid hemorrhage (n=11; 30%). 78% developed hemorrhage although no antiplatelet therapy was in use (n=29). Seven patients developed intracranial hemorrhage ipsilateral to prior bypass surgery (21%), while 29 of the control patients had a bypass surgery (88%; P =0.0001). There was no significant difference in terms of unilateral or bilateral disease type, history of hypertension, as well as imaging characteristics (high Suzuki stage and the presence of collateral pathways in conventional angiography, as well as ischemic defects and the presence of microbleeds on cerebral magnetic resonance imaging; P >0.05 in multivariate analysis, respectively). CONCLUSIONS: Bypass surgery was negatively associated with the development of intracranial hemorrhage in MMA in European patients. There was no difference in terms of a history of hypertension between groups, indicating that blood pressure is not the major contributor for rupture of fragile collateral vessels. The investigated imaging characteristics were not associated to hemorrhage onset and, therefore, are not suitable as a tool of screening for patients at risk.