Abstract TP324: Macrobleeds and Microbleeds: A Vascular Risk Factor Microangiopathy

Abstract

Background: The predominant type of cerebral small vessel disease (SVD) and clinical outcomes of patients who present with a combination of lobar and deep intracerebral hemorrhage (ICH)/microbleed (MB) locations (Mixed-ICH, see figure) is unknown. Methods: Out of 391 consecutive ICH, 75 (19%) had Mixed-ICH, and their demographics, clinical/laboratory features, and SVD neuroimaging markers were compared to 191 probable Cerebral Amyloid Angiopathy (CAA-ICH) and 125 strictly deep-MB and ICH (Deep-ICH) patients. ICH-recurrence on follow up was also analyzed. Results: Mixed-ICH patients had a higher prevalence of hypertension, diabetes, left ventricular hypertrophy rates, higher creatinine values, as well as more prevalent lacunes and basal ganglia (BG) enlarged perivascular spaces (EPVS) than CAA-ICH (all p<0.05). When compared to Deep-ICH, Mixed-ICH patients were older, had higher WMH volumes and MB count, and more prevalent lacunes and centrum semiovale EPVS (all p<0.05). In multivariable models, Mixed-ICH diagnosis was associated with higher creatinine, more lacunes and BG EPVS, than CAA-ICH (all p<0.05). When compared to Deep-ICH, Mixed-ICH patients were older and had more lacunes and MBs in multivariable models (all p<0.05). Annual risk of ICH-recurrence was 5.1% for Mixed-ICH, higher compared to Strictly Deep-ICH but lower than CAA-ICH (1.6% and 10.4%, respectively). Conclusions: Mixed-ICH, commonly seen when MRI obtained during etiologic workup, appears to be mostly driven by vascular risk factors similar to Strictly Deep-ICH, but demonstrates more severe parenchymal damage and higher ICH-recurrence risk.