Central Pulse Pressure Is an Independent Determinant of Vascular Remodeling in the Retinal Circulation

Abstract

A lthough the importance of hypertension as predictor of coronary heart disease and stroke has been known for a long time, the relative contribution of the individual components of peripheral blood pressure (BP) to the development of cardiovascular (CV) disease is still a matter of debate. [1][2][3][4][5] More striking nowadays, the importance of central hemodynamics is more and more acknowledged. Pathophysiologically, it seems consistent that the estimation of the central pressure in the aorta, which is actually the perfusion pressure to key organs, rather than the pressure in the arm, provides more relevant prognostic information. Indeed, it has been shown in a population-based study (the Strong Heart Study) 6 and in a hypertension trial (the Conduit Artery Function Evaluation [CAFÉ] study) 7 that the noninvasively measured central BP is superior to brachial BP in predicting CV outcomes. In a comprehensive review, Laurent et al 8 summarized the evidence that central pressure and pulse pressure (PP) are superior indicators of incident CV disease in a variety of prospective studies. Vascular remodeling, characterized by an increased mediato-lumen ratio (M/L) of small resistance and large arteries, has been identified as one of the early processes that occurs in response to increased BP and leads to hypertensive endorgan damage.9,10 The prognostic role of structural alterations of isolated subcutaneous small arteries and arterioles has been shown in arterial hypertension, with adverse prognosis in those patients with an increased M/L. 11,12 Moreover, in a former study it was shown that, although all known CV risk factors were considered, only PP and M/L were significantly associated with the occurrence of CV events. 11However, the evaluation of small artery and arteriolar structure of isolated subcutaneous small vessels requires an invasive procedure, namely the performance of a biopsy of subcutaneous tissue. Hence, this methodology is inadequate for routine patient management. In contrast, the analysis of the retinal vessels offers the opportunity to visualize the microvasculature of the body noninvasively, repeatedly, and safely in vivo. Hence, a new approach focuses on retinal arteriolar structural parameters by using scanning laser Doppler flowmetry (SLDF).Previously, both methodologies SLDF (in vivo) and myograph (in vitro) were assessed in patients with hypertension and normotensive controls. A close correlation was observed between M/L of subcutaneous small arteries and wall-to-lumen ratio (WLR) of retinal arteries, indicating that SLDF may provide similar information about microvascular morphology compared with an invasive, accurate, and prognostically Abstract-Pulse pressure has been recognized as a risk factor for stroke. Moreover, it was shown that central pulse pressure relates more strongly to vascular disease and outcome than (peripheral) brachial pulse pressure. Because vascular remodeling in the retinal circulation mirrors the 1 in the cerebral circulation and represents an easy, noninvasive possi...

Relationship of Wall-to-Lumen Ratio of Retinal Arterioles With Clinic and 24-Hour Blood Pressure

“…Alternatively, abnormalities in small artery structure could increase mean BP, which, in turn, increases shear stress and hence arterial stiffness of large arteries, creating a vicious cycle. 34,35 The correlation between remodeling of retinal arterioles and aortic central systolic or pulse pressure, observed in our study, confirms previous findings, 13 but lost significance when 24-hour BP was taken into consideration, indicating that the 24-hour pressure load may be a stronger determinant of changes in microvasculature than a single measurement of aortic central pressure. A possible explanation, as compared with previous findings, 14 may be related to the in vivo evaluation of retinal arterioles, which does not allow to completely separate structural from functional characteristics, 10 whereas the more invasive micromyographic technique clearly identifies the eutrophic or hypertrophic increase in small artery wall thickness.…”

“…Central BP, indicative of changes in large conduit arteries, was found to be an independent determinant of vascular remodeling in retinal arterioles, 13 supporting the concept that changes in macrovasculature and microvasculature are strongly interrelated and confirming previous results obtained with invasive assessment of small artery remodeling by micromyography. 14 Because the possible interrelationship between alterations in retinal arterioles and 24-hour BP has not been extensively evaluated and because the influence of ambulatory BP monitoring in respect to peripheral and central hemodynamics on retinal structure deserves further investigation, we considered worthwhile assessing the relationship of WLR of retinal arterioles with clinic brachial and 24-hour ambulatory BP and with central BP in normotensive subjects and in patients with primary hypertension.…”

Central Hemodynamics Are Associated With Cardiovascular Disease and Albuminuria in Type 1 Diabetes

“…7,[13][14][15] Moreover, an association between CPP and retinal disease was recently reported. 16 We have previously found 24-hour measurements of CASP and CPP obtained with a different device (BPro, HealthStats, Singapore) to be associated with diabetic complications (albuminuria degree, presence of CVD, retinopathy, and autonomic dysfunction) in this cohort. 10 With this study, we found no association between central hemodynamics and retinopathy but a significant association with presence of autonomic neuropathy (heart rate variability during deep breathing; data not shown).…”

Retinal Microvasculature and Cardiovascular Health in Childhood

“…32 Among adults, a crosssectional study among 135 individuals showed that arterial stiffness measured by central pulse pressure was inversely correlated with wall-tolumen ratio of retinal arterioles. 33 Another study among 197 adults found that retinal arteriolar narrowing was associated with higher carotidfemoral pulse wave velocity. 34 No previous study in children examined the associations of retinal vessel calibers with carotid-femoral pulse wave velocity.…”