Flow-mediated slowing of brachial-radial pulse wave velocity: Methodological aspects and clinical determinants

Abstract

Background: Recent studies proposed that deceleration in pulse wave velocity (PWV) following reactive hyperaemia might reflect arterial distensibility and endothelial function. We therefore investigated methodological aspects and clinical determinants of new indexes of flow-mediated slowing (FMS) of PWV in a community-based sample. Methods: In 71 subjects (mean age, 60.3 years; 50.7% women), we continuously assessed brachial-radial PWV using Vicorder® at baseline and after 3-min or 5-min suprasystolic upper-arm cuff occlusion. We calculated the relative change (Δ) in PWV per each 30 s intervals during 4 min of post-occlusion. We performed stepwise regression analyses to assess determinants of the PWV response. Results: The peak FMS was detected at the first PWV recording obtained after occlusion. Overall, the decline in PWV during hyperaemia was significantly greater after 5-min of occlusion as compared to 3-min (effect sizes for 0–240 s intervals: −1.83% to −9.63%; P ≤ 0.037). PWV declined significantly less with higher age during the 0–60 s post-occlusion intervals (P ≤ 0.0053). On the other hand, after 120 s of post-occlusion, ΔPWV remained significantly lower in subjects with high diastolic blood pressure and oxidized LDL, and in smokers (P ≤ 0.028). Consequently, as compared to healthy reference group, participants with cardiovascular risk factors exhibited a delay in age-adjusted recovery of PWV after 5-min of occlusion (P ≤ 0.039). Conclusions: Our findings confirm the use of a 5-min occlusion time for the assessment of vasomotor function by FMS. Whereas the early FMS response might deteriorate with ageing, cardiovascular risk factors such as smoking, oxidative stress and hypertension might affect recovery of PWV after reactive hyperaemia.

Keywords

• General population
• Endothelial function
• Flow-mediated slowing
• Pulse wave velocity