Eh. Lieberman et al., FLOW-INDUCED VASODILATION OF THE HUMAN BRACHIAL-ARTERY IS IMPAIRED INPATIENTS LESS-THAN-40 YEARS OF AGE WITH CORONARY-ARTERY DISEASE, The American journal of cardiology, 78(11), 1996, pp. 1210-1214
zThe objective of this study was to determine whether abnormal flow-in
duced endothelium-dependent vasodilation in the brachial artery identi
fies young patients with coronary artery disease (CAD). High-resolutio
n ultrasonography was used to measure vascular reactivity in a periphe
ral conduit vessel, the brachial artery, in 14 young men with CAD and
in 11 age-matched, healthy, merle volunteers, Endothelium-dependent va
sodilation was determined by measuring the change in brachial artery d
iameter during increases in flow induced by reactive hyperemia. Endoth
elium-independent vasodilation was assessed by administration of subli
ngual nitroglycerin. To ascertain whether flow-mediated vasodilation i
n humans is mediated by endothelium-derived nitric oxide, brachial art
ery diameter was measured during reactive hyperemia, before and during
administration of the nitric oxide synthase antagonist N-G-monomethyl
-L-arginine (L-NMMA). Brachial artery diameter was also measured durin
g intraarterial infusion of acetylcholine and nitroprusside before and
after administration of L-NMMA. Flow-induced vasodilation was less in
patients with CAD than in healthy volunteers (1.3+/-1.1% vs 6.2+/-0.7
%, p <0.05). Nitroglycerin increased brachial artery diameter similarl
y in each subject group (11.3+/-1.0% vs 15.8+/-1.2%, p=NS). L-NMMA inh
ibited flow-mediated vasodilarion and the vasodilative response to ace
tylcholine, but did not affect the response to nitroprusside. It is co
ncluded that abnormal flow-induced endothelium-dependent vasodilation
occurs in the brachial artery of young patients with CAD. (C) 1996 by
Excerpta Medica, Inc.