Comparison of beta2-adrenergic and hyperemia-induced arterial vasodilation assessed by digital pulse contour analysis

. The Reflection Index (RIDVP) derived from digital volume pulse (DVP) analysis has proved to be useful in the assessment of endothelium‑dependent vasodilation induced by albuterol. Little is known of the effect of shear‑stress‑induced vasorelaxation on RIDVP.Material and Methods. Thirty three healthy volunteers (22 females, 11 males, mean age 57 yrs) were recruited. Assessment of endothelium‑dependent vasorelaxation was performed by the analysis of digital volume pulse after albuterol challenge or locally‑induced hyperemia. Results. he hyperemia‑induced vasodilation led to a significant decrease of RIDVP in comparison with the values obtained at rest (∆RIHyper 69 ± 2 % vs 64 ± 2, p < 0.0001). Similarly albuterol administration resulted in a significant drop in RIDVP (∆RIAlb 71 ± 2 % vs 67 ± 2 %, p < 0.0001). There was no significant difference between ∆RIHyper and ∆RIAlb (5.2 ± 0.8 % vs 4.6 ± 1.0 %, p = 0.61). We observed a significant correlation between the small vessel reaction in response to albuterol or hyperemia (r = 0.52, p = 0.01).Conclusions. Our study demonstrated that hyperemia‑induced changes in the Reflexion Index derived from the digital volume pulse are similar to those observed after albuterol‑challenge and both are correlated.