Wall-to-lumen ratio of retinal arterioles: A reproducible, valid and noninvasive approach for evaluation of early arteriolar changes in arterial hypertension in vivo

摘要

Small resistance arteries (small arteries and arterioles with a diameter <350 mum) are major regulators of peripheral vascular resistance, which represents the hemoclynamic hallmark of arterial hypertension. According to Hagen-Poiseuille's law, flow resistance is inversely related to the fourth power of the vessel. Thus, even mild narrowing (either structural or functional or both) increases total peripheral vascular resistance, and thereby blood pressure. To determine changes in small arteries and arterioles, either within a participant or between participants, media-to-lumen ratio or wall-to-lumen ratio of small resistance arteries and arterioles has been measured and found to represent an early phenomenon in the pathophysiology of arterial hypertension. Moreover, in a cohort of 45 never-treated individuals with primary hypertension and 40 normotensive individuals, SBP and DBP were significantly related to media-to-lumen ratio of isolated subcutaneous small arteries and arterioles indicating that the degree of blood pressure elevation is related to the severity of small artery and arteriolar changes .