Flow-mediated dilatation: learning curve study with a novice operator

Abstract

AbstractIntroductionBrachial artery flow-mediated dilatation (FMD) is commonly measured to assess endothelial function in experimental and clinical research studies. However, attaining reproducible results can be challenging, especially among inexperienced operators. Until now, no detailed learning curve study of novice operators has been published.MethodsWe assessed the learning curve of FMD measurement in one novice operator. Following a one-week basic training period, the operator performed duplicate measurements on 6-8 individuals per week, for six weeks. The operator followed the recommendations of the most recent FMD measurement guideline. Duplex ultrasound was used for the simultaneous and continuous measurement of brachial artery diameter and local blood flow velocity. Following a 1-minute recording of baseline diameter (D), FMD was measured after a 5-minute period of occlusion of the proximal forearm vessels. Inter-session coefficient of variation (CV) values for D and FMD were calculated for each week.ResultsThe majority of participants did not have any cardiovascular disease history. The number of volunteers assessed each week were the following: 8, 7, 7, 6, 7, 7 individuals, from week 1 to week 6. CV values for both D and FMD exhibited a decreasing trend over the training period, ending at 1.73% for D and 14.24% for FMD at week 6. The CV values at week 6 were within the range outlined in the most recent FMD guideline for proficiency.ConclusionsWithin a reasonable timeframe, and with careful adherence to measurement guidelines, the attainment of sound reproducibility in FMD measurements by a novice operator is feasible.