Aortic size index enlargement is associated with central hemodynamics in essential hypertension

Abstract

The aim of this study was to evaluate the association between brachial and central blood pressure (bBP and cBP) levels and aortic root dilatation (ARD) in essential hypertensive patients. A total of 190 untreated and treated essential hypertensive patients (mean age, 55±11 years) were considered for this analysis. We measured pulsatile hemodynamics and the proximal aortic diameter directly using tonometry, ultrasound imaging (echocardiography) and Doppler. Ninety-one hypertensive patients had an ARD (defined as aortic size index (ASi)42 cm/m 2 ). Central hemodynamic variables were significantly associated with ASi. Patients with increased ASi were significantly older (60 ± 10 vs. 50 ± 11 years, Po0.0001) and had higher levels of the augmentation index (AIx; 28±10 vs. 21±10 Po0.0001), augmentation pressure (AP; 13±6 vs. 8±5 mm Hg, Po0.0001), and central pulse pressure (cPP; 44 ± 10 vs. 39 ± 8 mm Hg, Po0.0001) compared with patients with normal ASi. In a logistic regression analysis, the AIx was the only significant predictor of ASi. In hypertensive patients, the AIx and cBP were associated with ARD, whereas the bBP was not. Patients with an increased ASi may lose part of the elastic properties of the aorta, demonstrating a strict correlation between ASi and central hemodynamic indexes, in particular, the cPP and AIx.

Large Artery Stiffening and Remodeling Are Independently Associated With All-Cause Mortality and Cardiovascular Events in Chronic Kidney Disease

“…In this study, carotid internal diameter was an independent prognostic factor for all-cause mortality, whereas circumferential wall stress, which integrates diameter, intimamedia thickness, and pressure, was not. Arterial enlargement is a process associated with supposedly normal aging 32 but has also been associated with pathological conditions, such as hypertension in menopausal women, 33 hypertension, 34,35 CKD, 6 and end-stage renal disease patients. 36 In hypertensive patients, an increase in aortic diameter has been independently associated with target organ damage, such as cardiac hypertrophy.…”

The Structural Factor of Hypertension

“…This finding is in accordance with numerous in vitro studies showing that cyclic stretch exerts a greater influence than static load on phenotype and growth of VSMCs (including synthesis of DNA, smooth muscle myosin, and collagen). [53][54][55] The diameter of the aortic root has been studied in hypertensives 52 : the higher the central PP, the larger the aortic root diameter, suggesting as discussed above a major role of pressure pulsatility on aortic root enlargement. MRI, which precisely investigates the geometry of aorta in hypertensives, showed that ascending aortic diameter and increased aortic arch length and width, as well as decreased aortic arch curvature, were highly correlated with increased central PP.…”

“…The enlargement of proximal elastic large arteries with aging and elevated mean blood pressure has been extensively described in humans in studies using ultrasounds, particularly high-resolution echotracking systems. [43][44][45][46][47][50][51][52] The enlargement of large arteries, such as the thoracic aorta and the common carotid artery (CCA), is generally attributed to fracture of the load-bearing elastin fibers in response to the fatiguing effect of steady and pulsatile tensile stress. However, growth and apoptosis of VSMCs could also be involved.…”

“…50 If local pressure pulsatility plays a major role on aortic root enlargement, conversely the consequences of aortic remodeling on central BP remain unclear. [50][51][52] By contrast to studies in hypertensives, studies in normotensives 51,59 reported a negative relationship between central PP and aortic root diameter, ie, the smaller the lumen diameter, the higher the central PP. Lam et al 51 thus suggested that the lack of aortic root dilatation, increasing characteristic impedance (Z c ) and wave reflection, would be the cause of high central PP and systolic blood pressure (SBP).…”

The Association between Prolactin, High-Sensitivity C-Reactive Protein and Framingham Risk Score in Menopause

“…Increased left atrial and aortic root diameters can be observed in hypertension with high hs-CRP levels [22]. Milan et al [23] demonstrated a strict correlation between aortic size index and central hemodynamic parameters in patients with essential hypertension. Our results support this with a positive correlation with diastolic interventricular septum thickness, and aortic root and left atrium diameters.…”