Abstract WMP97: Acute Cerebral Ischemia After Aggressive Blood Pressure Reduction in Primary Intracerebral Hemorrhage: How Low Can You Go?

Introduction: Despite studies of aggressive blood pressure reduction in primary intracerebral hemorrhage (ICH), the potential for inducing ischemia remains a concern. The primary objective of this study is to determine the relationship between blood pressure and acute cerebral ischemia following ICH. Methods: We performed a retrospective chart review of patients with primary ICH admitted between January 2013 and December 2014 in whom MRI brain with diffusion-weighted imaging (DWI) was performed within 2 weeks of admission. Acute ischemia was defined as DWI hyperintensity with corresponding apparent diffusion coefficient hypointensity. Lesions adjacent to the ICH or after an invasive procedure were excluded and all MRIs were performed prior to digital subtraction angiography. Serial blood pressure measurements were collected from admission to 72h post ictus. Clinical deterioration was defined as any acute exam change not explained by seizure, hematoma expansion or other medical causes. Results: Among 119 patients with primary ICH (mean age 69.3 years, 58% males, 65% Caucasians), 28 (23.5%) had acute ischemia. Acute ischemia was associated with lower mean 24-hour SBP (132 mmHg in DWI+ versus 141 mmHg in DWI-, p<0.001), greater mean change in SBP from admission to 24 hours (67 mmHg in DWI+ versus -42 mmHg in DWI-, p=0.002), lower mean minimum SBP at 72 hours (104 mmHg in DWI+ versus 111 mmHg in DWI-, p=0.008) and lobar ICH location (35% in DWI+ versus 14% in DWI-, p=0.009). Minimum SBP <120 mmHg during the first 72 hour after ICH has a sensitivity of 96% in predicting DWI lesions in patients with ICH (p=0.014). Overall, patients with DWI+ lesions had a higher incidence of clinical deterioration (32% in DWI+ versus 6% in DWI-, p<0.001) and longer length of stay compared to patients without DWI lesions (13 days in DWI+ versus 8 days in DWI-, p=0.006). Hematoma volume, initial NIH Stroke Scale and admission SBP were not significantly associated with DWI lesions in patients with primary ICH. Conclusions: Aggressive SBP reduction, particularly SBP<120 mmHg within the first 72h of ICH, can be associated with acute cerebral ischemia. A third of acute ischemic lesions are associated with clinical deterioration.