I018 Short and long lasting action of shear stress changes on diameter of conduit arteries in patients with arterial hypertension

Results Compared with normotensive control subjects, initial vascular diameter (D0), was higher in hypertensive subjects (3.76±0.28 vs. 4.32±0.14, P<0.01). Initial shear stress was not significantly different between the two groups. Therefore, after reactive hyperemia test (RHtest) shear stress as well as changes of shear stress were higher in hypertensive population compared with healthy control subjects (5.86±0.32 vs. 5.15±0.32, P<0.05 and -0.35±0.09 vs. -0.71±0.09; P<0.001). Initial vascular diameter was in a negative correlation with initial shear stress, as well as with after RHtest shear stress, but there was appeared positive correlation between initial vascular diameter and changes of it. Conclusions Arterial hypertension is associated with permanent changes of vascular wall diameter via neuro-humoral factors. Therefore, obtained results confirm an opinion that different from the short action of the changes of shear stress, vascular diameter of conduit arteries increases in response to the chronic increase of the shear stress.