Dynamic but not static cerebral autoregulation is impaired in acute ischaemic stroke

It remains unclear as to whether dynamic and static cerebral autoregulation (CA) are impaired in acute ischaemic stroke, and whether these changes are related to stroke subtype. This could have important implications with reg ard to poststroke prognosis and the management of blood pressure (BP) in th e acute post-ictal period. Using transcranial Doppler ultrasonography and n on-invasive manipulation of BP, we compared both mechanisms in 61 patients with ischaemic stroke within 96 h of ictus, and 54 age- and sex-matched con trols. There was no difference in static and dynamic CA indices between the various stroke subtypes, Combining all stroke subtypes dynamic autoregulat ion, as measured using thigh cuff release, was significantly impaired in bo th the affected and non-affected stroke hemispheres compared to controls (m ean autoregulation index 4.1 +/- 3.3, 4.8 +/- 3.1 and 6.2 +/- 2.3, respecti vely, p < 0.05), By comparison static autoregulation, assessed using isomet ric hand grip and thigh cuff inflation, was not significantly different. In conclusion, dynamic but not static CA appears to be globally impaired in a cute ischaemic stroke. This deserves further study and may identify possibi lities for therapeutic intervention. Copyright (C) 2000 S. Karger AG, Basel .