Comparison of baseline brachial artery measurements and effect on peak flow-mediated dilation

Abstract

The aim of this study was to examine the effect of pre-occlusion, occlusion, and post-occlusion baseline brachial artery measurements on the calculation of peak flow mediation dilation (FMD). Ultrasound imaging of the brachial artery following reactive hyperemia was conducted in 418 children and 533 adults. Baseline brachial artery measures were a 10-second average before (pre-occlusion), during (occlusion), and after (post-occlusion) hyperemia. Peak FMD was defined as the change from baseline to the peak brachial artery diameter following reactive hyperemia. Pre-occlusion, occlusion, and post-occlusion baseline measures of brachial artery diameter were not significantly different in children (3.15±0.51, 3.14±0.50 vs. 3.11±0.50 mm, P=0.179) or adults (3.81±0.72, 3.81±0.73 vs. 3.79±0.73 mm, P=0.201). Peak FMD values were not significantly different when calculated from pre-occlusion, occlusion, or post-occlusion baselines in children (6.77±5.78, 6.93±4.03 vs. 7.85±3.62%, P=0.208) or adults (6.06±5.53, 6.12±3.94 vs. 6.62±3.70%, P=0.266). We found no differences in FMD regardless of the baseline brachial artery diameter used in children or adults. Therefore, comparison of data from studies utilizing different measures of baseline brachial diameter can be conducted without correction of data.