Association of Systolic Blood Pressure and Cerebral Collateral Flow in Acute Ischemic Stroke by Stroke Subtype

Background and PurposeCollateral flow in acute ischemic stroke is known as a predictor of treatment outcome and long-term prognosis. However, factors determining the initial collateral flow remain unclear. We investigated factors related to collateral flow in patients with acute ischemic stroke caused by large vessel occlusion (AIS-LVO) and further analyzed the results according to stroke etiology. MethodsThis was a retrospective study using prospective stroke registry data from a single university hospital from October 2014 to May 2021. AIS-LVO with middle cerebral artery M1 occlusion identified by pre-treatment multiphasic computed tomography angiography was included. Collateral flow score was graded on a 6-point ordinal scale according to pial arterial filling. ResultsA total of 74 patients [cardioembolism (CE): 57; large artery atherosclerosis (LAA): 17] was included. The mean age of all patients was 72.2 +/- 11.7 years, and 37.8 % (n = 28) were men. Multivariate regression analysis showed that initial SBP [odds ratio (OR): 0.994; 95% confidence interval (CI): 0.990-0.998; p = 0.002] and stroke etiology (OR: 0.718; 95% CI: 0.548-0.940; p = 0.019) were independent factors of the collateral flow grade. Collateral flow grade was independently associated with initial SBP in the CE group (OR: 0.993; 95% CI: 0.989-0.998; p = 0.004) but not in the LAA group (OR: 0.992; 95% CI: 0.980-1.004; p = 0.218). Initial SBP was significantly correlated with NIHSS score in the CE group but not in the LAA group (r(2)= 0.091, p = 0.023; r(2) = 0.043, p = 0.426, respectively). ConclusionsElevated initial SBP was associated with poor cerebral collateral flow and more severe symptoms in the CE group, but not in the LAA group in patients with AIS-LVO. These findings suggest differential effects of initial SBP elevation on collateral flow by stroke subtypes.

Automated summary

This study investigated the factors related to initial collateral flow in patients with acute ischemic stroke and analyzed the results according to stroke etiology. The results showed that elevated initial systolic blood pressure was associated with poor cerebral collateral flow and more severe symptoms in the cardioembolism group, but not in the large artery atherosclerosis group.