Central pulse pressure is associated with retinal arteriolar wall thickness and wall cross sectional area as evaluated by adaptive optics

Abstract

IntroductionIn 1991 Baumbach et al demonstrated taht pulse pressure (PP) but not mean arterial pressure (MAP) was correlated with pial arterioles wall cross-sectional area (WCSA)in rats. Adaptive optics (AO) allows a near-histological evaluation of retinal microcirculation (which shares the same embryological origins as the cerebral one) in a completely non-invasive fashion in humans. The aim of the study was to evaluate the relationship between PP/MAP and retinal arteriolar microcirculation.MethodsAssessment included office BP measurements realized with SphygmoCor® with the patient resting in a supine position for at least 5 minutes followed by retinal microvascular analysis with AO RTX1® Camera to measure WT, internal diameter (ID), wall-to-lumen ratio (WLR) and WCSA, realized with the patients sitting in a stable position for at least 5 minutes.ResultsThe study cohort consisted of 103 subjects on primary prevention and at intermediate risk, aged 20 to 80 years, with arterial hypertension and/or dyslipidemia. Study population was stratified according to median central PP (40 mmHg) and MAP (94 mmHg). Main results are shown in Table 1. Patients with a higher central PP showed an increased WT and WCSA. No difference was observed in WT and WCSA according to MAP.ConclusionsCentral PP is associated with structural changes in retinal microcirculation, namely a wall thickening and an increased vascular mass, as previously found on cerebral arterioles. Adaptive Optics allows a non-invasive evaluation of a microvascular territory which shares many morphological and physiological properties with the cerebral microcirculation, representing a promising tool for the prevention of cerebrovascular events.Pulse PressureMean Arterial Pressure<40 mmHg≥ 40 mmHg< 94 mmHg≥ 94 mmHgSmall retinal arteriesn = 49n = 53pn = 48n= 54pWall Thickness.- μm21.7 + 3.724.3 ± 4.20.00222.6 ± 3.423.4 ± 4.70.794Internal Diameter.- μm77.7 ± 13.181.2 ± 9.40.20779.1 ± 9.679.9 ± 12.90.417Wall tg Lumen Ratio0.284 ± 0.050.302 ± 0.050.1200.287 ± 0.040.298 ± 0.060.410Wall Cross Seclionnal Area. -μm23067 ± 8733585 ± 8450.0053245 ± 7553417 ± 9990.529