Carotid artery reactivity to isometric hand grip exercise identifies persons at risk and with coronary disease.
BACKGROUND
The change in brachial artery diameter (DBA(d)) following release of an occluding cuff (BAO(cclR)) has been used to characterize local endothelial function and coronary risk. We designed a study to determine the CA diameter (CA(d)) response to exercise (IHG), whether the response is influenced by coronary risk, and compare it with the BAO(cclR) method.


RESULTS
High resolution ultrasound was used to detect the DCA(d) in response to120 s of 33% of maximum and DBA(d) was measured 60 s following release of an occluding cuff. There was no change in CA(d) during IHG. At 90 s following release, CA(d) dilated >0.1 mm in 95% of volunteers with average risk (mean 0.42+/-0.25 mm or 5.97+/-3.5%). There was no change or constriction in 62% of high risk (0.01+/-0.28 mm, 0.0+/-3.6%), and predominantly constriction in CAD subjects (-0.22+/-0.23 mm, -0.01+/-3.2%), P=0.0001 for trend and 0.01 between groups. The %DCA(d) following IHG and %DBA(d) following OcclR were highly correlated, r=0.66, P=0.0001. The major determinant of response to each stressor was group (%DBA(d) R(2)=0.55 and %DCA(d) R(2)=0.52).


CONCLUSIONS
The reactivity of the carotid artery to IHG is highly influenced by coronary risk, and may be an additional modality to characterize pre-clinical CAD and assess treatment strategies.
Rubenfire
Melvyn
M
Division of Cardiology, Department of Internal Medicine, University of Michigan Health System, P.O. Box 363, 24 Frank Lloyd Wright Drive, Ann Arbor, MI 48106-0363, USA. mrubenfi@umich.edu
Cao
Ning
N
Smith
Dean E
DE
Mosca
Lori
L
D000328:Adult; D000367:Age Factors; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000188:drug therapy / Q000503:physiopathology; D001916:Brachial Artery / Q000187:drug effects / Q000503:physiopathology; D002339:Carotid Arteries / Q000187:drug effects / Q000503:physiopathology*; D003327:Coronary Disease / Q000503:physiopathology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000503:physiopathology; D005996:Nitroglycerin / Q000627:therapeutic use; D011237:Predictive Value of Tests; D012307:Risk Factors; D014665:Vasodilator Agents / Q000627:therapeutic use
D014665:Vasodilator Agents; D005996:Nitroglycerin