Serial changes in static and dynamic cerebral autoregulation after acute ischaemic stroke.
BACKGROUND
The longitudinal changes in static and dynamic cerebral autoregulation (CA) following acute ischaemic stroke are unknown and were assessed in this study.


METHODS
Fifty-four ischaemic stroke patients were studied within 96 h of ischaemic stroke and again 7-14 days later, using transcranial Doppler techniques to measure CA. Results were compared to an age-, sex- and blood pressure (BP)-matched control group. Static BP pressor stimulus was produced by thigh cuff inflation and dynamic stimulus by rapid thigh cuff release.


RESULTS
Dynamic, but not static, CA was globally impaired at initial (mean dynamic CA index 3.9 +/- 3.1 vs. 6.2 +/- 2.3, p < 0.005) and follow-up studies (dynamic CA 3.9 +/- 2.8 vs. 6.2 +/- 2.3, p < 0.01) in stroke patients compared to controls. Static CA was similar in stroke patients and controls and was unchanged during follow-up.


CONCLUSIONS
Dynamic, but not static, CA is impaired after acute ischaemic stroke and remains abnormal for at least 1-2 weeks post ictus. These changes are present in both the affected and non-affected hemispheres and are unrelated to previous antihypertensive treatment, baseline BP levels or BP changes after stroke, age or stroke type.
Dawson
Suzanne L
SL
University Division of Medicine for the Elderly, Leicester Warwick Medical School, University of Leicester, UK.
Panerai
Ronney B
RB
Potter
John F
JF
D000208:Acute Disease; D000368:Aged; D000375:Aging / Q000502:physiology; D000465:Algorithms; D001794:Blood Pressure / Q000502:physiology; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality / Q000502:physiology; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011311:Pressoreceptors / Q000502:physiology; D020521:Stroke / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017585:Ultrasonography, Doppler, Transcranial