Comparison of baseline brachial artery measurements and effect on peak flow-mediated dilation.
BACKGROUND
Flow-mediated dilation (FMD) following reactive hyperaemia can use different time-point measures for baseline diameter. The aim of this study is to compare preocclusion, occlusion and postocclusion baseline brachial artery measurements on the calculation of peak FMD.


METHODS
Ultrasound imaging of the brachial artery following reactive hyperaemia was conducted in 418 children and 533 adults. Baseline brachial artery measures were a 10-s average before (preocclusion), during (occlusion) and after (postocclusion) hyperaemia. Peak FMD was defined as the greatest percent change from baseline to the peak brachial artery diameter following reactive hyperaemia.


RESULTS
Preocclusion, occlusion and postocclusion baseline measures of brachial artery diameter were not significantly different in children (3·15 ± 0·51, 3·14 ± 0·50 versus 3·11 ± 0·50 mm, P = 0·179) or adults (3·81 ± 0·72, 3·81 ± 0·73 versus 3·79 ± 0·73 mm, P = 0·201). Peak FMD values were not significantly different when calculated from preocclusion, occlusion or postocclusion baselines in children (6·77 ± 5·78, 6·93 ± 4·03 versus 7·85 ± 3·62%, P = 0·208) or adults (6·07 ± 5·53, 6·14 ± 3·94 versus 6·62 ± 3·70%, P = 0·266).


CONCLUSIONS
We found no difference in FMD regardless of the baseline brachial artery diameter used in children and adults. Therefore, compilation of data and comparison of results from studies utilizing different measures of baseline brachial diameter may be able to be conducted.
Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.
Joseph D
JD
Ostrem
Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.|Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, USA.
Donald R
DR
Dengel
Laboratory of Integrative Human Physiology, School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.
Kara L
KL
Marlatt
Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, USA.
Julia
J
Steinberger
D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods*; D001916:Brachial Artery / Q000502:physiology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014111:Tourniquets; D014655:Vascular Resistance / Q000502:physiology*; D014664:Vasodilation / Q000502:physiology*; D055815:Young Adult
adult; endothelium-dependent dilation; ultrasound; vascular function; youth