Impaired baroreceptor reflex sensitivity in acute stroke is associated with insular involvement, but not with carotid atherosclerosis.
OBJECTIVE
Impaired baroreflex sensitivity (BRS) has been previously shown to be of prognostic value in patients with cardiovascular disease and stroke. Because baroreflex seems to be blunted by both carotid atherosclerosis and by lesions affecting central processing, controversy exists regarding the etiology of stroke-related baroreflex changes. The insula may play a central role in baroreflex modulation. The aim of the study was therefore to examine BRS in patients with acute stroke with regard to carotid atherosclerosis and insular involvement.


METHODS
We evaluated spontaneous BRS in 96 patients with acute stroke within 72 hours of ictus and 41 control subjects using a sequential crosscorrelation method.


RESULTS
Fifty-two patients with ischemic stroke and 44 patients with intracerebral hemorrhage, mean age 58.4 years, were included. With comparable carotid atherosclerosis profiles, patients with stroke had significantly lower BRS than control subjects (3.3 versus 5.3, P<0.001). Carotid atherosclerosis had no influence on variance of the BRS values in the acute stroke group. Patients with insular involvement had significantly lower BRS than patients with no insular involvement (2.55 versus 4.35, P=0.001) or control subjects (2.55 versus 5.3, P<0.001). Furthermore, patients with left insular involvement had significantly lower BRS than patients with right insular involvement (2.3 versus 3.5, P=0.049). There was no significant difference between patients with no insular lesions and control subjects (P=0.263).


CONCLUSIONS
We demonstrated that baroreflex impairment in acute stroke is not associated with carotid atherosclerosis but with insular involvement. Both insulae seem to participate in processing the baroreceptor information with the left insula being more dominant.
Sykora
Marek
M
Department of Neurology, University of Heidelberg, Germany. marek.sykora@med.uni-heidelberg.de
Diedler
Jennifer
J
Rupp
Andre
A
Turcani
Peter
P
Steiner
Thorsten
T
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D002545:Brain Ischemia / Q000150:complications; D002340:Carotid Artery Diseases / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000150:complications; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D054969:Primary Dysautonomias / Q000150:complications / Q000503:physiopathology; D011446:Prospective Studies; D020521:Stroke / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed; D055815:Young Adult