Aortic Aortic Augmentation Index Research Articles

Arterial stiffness assessment in patients with resistant hypertension using pulse wave analysis

Abstract Introduction People living with resistant hypertension (RH) have a higher prevalence of target organ damage, and demonstrate increased risk of cardiovascular (CV) morbidity and mortality. There are distinctive vascular structural and functional changes associated with hypertension. Among these, endothelial dysfunction and increased arterial stiffness are prevalent. Increased aortic augmentation index (AIx) is a non-invasive hemodynamic indicator of systemic arterial stiffness, which has been associated with hypertension; however, there are less data in RH patients. Purpose To test the hypothesis that people living with RH have increased AIx compared to those with controlled essential hypertension (CH) and normotensive controls (NC); and to explore demographic and clinical variables related to AIx. Methods In our observational study, 54 participants: 17 with RH (mean age 60.5±12.4 years), 18 with CH (57.7±12.2 years), and 19 NC (54.7±11.9 years) were recruited. Anthropometric and resting office blood pressure (BP) measurements were obtained. Pulse wave analysis was performed using a commercially available device (Vicorder) to measure central BP, aortic pulse pressure, mean arterial pressure (MAP), aortic augmentation pressure and AIx. Results The study groups were matched for age, sex, ethnicity, height, body surface area and heart rate (P>0.05) (Table 1). Both office and central BP readings were elevated in RH group compared to CH and NC (162/102mmHg vs 126/86mmHg and 118/80mmHg, P<0.001) and (163/83mmHg vs 131/73mmHg and 120/67mmHg, P<0.05). Aortic pulse pressure, MAP and aortic augmentation pressure were significantly increased in patients with RH compared to other groups (P<0.001). AIx was markedly increased in RH compared to CH and NC (31±7% vs 23±8% and 21±9%, P=0.001, respectively). Antihypertensive medications were similar between both hypertensive groups, except for diuretics and beta-blockers which were more prevalent in the RH group (100% vs 28% and 47% vs 6%, P<0.05, respectively). In stepwise regression analysis, elevated AIx was significantly and independently associated with the presence of RH (β=6.4, P=0.005), age (β=.23, P=0.005), female sex (β=6.3, P=0.003) and body mass index (β=.71, P=0.038). Conclusion AIx is increased in RH patients and independently related to the presence of RH, age, female sex and body mass index. Increased arterial stiffness and reduced arterial compliance in patients with RH may play an important role in the progression of serious CV complications seen in these patients. The non-invasive assessment of arterial stiffness indices such as AIx in RH patients may be valuable to provide prognostic and therapeutic insights.Table 1

Maternal hemodynamics and neonatal birth weight in pregnancies complicated by gestational diabetes: new insights from novel causal inference analysis modeling.

ObjectiveNormal pregnancy is characterized by significant changes in maternal hemodynamics that are associated with fetal growth. Pregnancies complicated by gestational diabetes mellitus (GDM) are associated with large‐for‐gestational age and macrosomia, but the relationship between maternal hemodynamic parameters and birth weight (BW) among women with GDM has not been established. Our objective was to investigate the influence of maternal hemodynamics on neonatal BW in healthy pregnancies and in those complicated by GDM.MethodsThis was a prospective, cross‐sectional case–control study of women aged ≥ 16 years with a singleton viable pregnancy, recruited between January 2016 and February 2021 at Leicester Royal Infirmary, Leicester, UK. GDM was defined as a fasting glucose level ≥ 5.3 mmol/L and/or serum glucose level ≥ 7.8 mmol/L, 2 h following a 75‐g oral glucose load. We collected data on maternal characteristics and pregnancy outcome, including body mass index (BMI) at booking and BW centile adjusted for gestational age at delivery. Maternal hemodynamic parameters were assessed at 34–42 weeks' gestation using the Arteriograph® and bioreactance techniques. Graphical causal inference methodology was used to identify causal effects of the measured variables on neonatal BW centile.ResultsIncluded in the analysis were 141 women with GDM and 136 normotensive non‐diabetic pregnant controls. 62% of the women with GDM were managed pharmacologically, with metformin and/or insulin. Variables included in the final model were cardiac output (CO), mean arterial pressure (MAP), total peripheral resistance (TPR), aortic augmentation index (AIx), aortic pulse wave velocity (PWV) and BMI at booking. Among the controls, maternal BMI, CO and aortic PWV were significantly associated with neonatal BW. Each SD increase in booking BMI produced an increase of 8.4 BW centiles (P = 0.002), in CO produced an increase of 9.4 BW centiles (P = 0.008) and in aortic PWV produced an increase of 7.1 BW centiles (P = 0.017). We found no significant relationship between MAP, TPR or aortic AIx and neonatal BW. Maternal hemodynamics influenced neonatal BW among the women with GDM in a similar manner to that in the control group, but only the relationship between maternal BMI and neonatal BW reached statistical significance, with a 1‐SD increase in BMI producing an increase of 6.1 BW centiles (P = 0.019).ConclusionsMaternal BMI, CO and PWV were determinants of BW in our control group. The relationship between maternal hemodynamics and neonatal BW was similar between women with GDM and healthy controls. Our findings therefore suggest that fetal growth restriction in pregnancies complicated by GDM may indicate maternal cardiovascular dysfunction. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Carotid stiffness, intima-media thickness and aortic augmentation index among adults with SARS-CoV-2.

New Findings What is the central question of this study? We sought to investigate whether carotid stiffness, carotid intima–media thickness and the aortic augmentation index are altered in young adults 3–4 weeks after contraction of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) compared with young healthy adults. What is the main finding and its importance? We found that carotid stiffness, Young's modulus and the aortic augmentation index were greater in young adults who tested positive for SARS‐CoV‐2 compared with healthy young adults. These findings provide additional evidence for detrimental effects of SARS‐CoV‐2 on young adult vasculature, which might have implications for cardiovascular health. Contracting severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has been observed to cause decrements in vascular function of young adults. However, less is known about the impact of SARS‐CoV‐2 on arterial stiffness and structure, which might have additional implications for cardiovascular health. The purpose of this study was to assess the carotid artery stiffness and structure using ultrasound and the aortic augmentation index (AIx) using applanation tonometry in young adults after they tested positive for SARS‐CoV‐2. We hypothesized that carotid artery stiffness, carotid intima–media thickness (cIMT) and aortic AIx would be elevated in young adults with SARS‐CoV‐2 compared with healthy young adults. We evaluated 15 young adults (six male and nine female; 20 ± 1 years of age; body mass index, 24 ± 3 kg m−2) 3–4 weeks after a positive SARS‐CoV‐2 test result compared with young healthy adults (five male and 10 female; 23 ± 1 years of age; body mass index, 22 ± 2 kg m−2) who were evaluated before the coronavirus 2019 pandemic. Carotid stiffness, Young's modulus and cIMT were assessed using ultrasound, whereas aortic AIx and aortic AIx standardized to 75 beats min−1 (AIx@HR75) were assessed from carotid pulse wave analysis using SphygmoCor. Group differences were observed for carotid stiffness (control, 5 ± 1 m s−1; SARS‐CoV‐2, 6 ± 1 m s−1), Young's modulus (control, 396 ± 120 kPa; SARS‐CoV‐2, 576 ± 224 kPa), aortic AIx (control, 3 ± 13%; SARS‐CoV‐2, 13 ± 9%) and aortic AIx@HR75 (control, −3 ± 16%; SARS‐CoV‐2, 10 ± 7%; P < 0.05). However, cIMT was similar between groups (control, 0.42 ± 0.06 mm; SARS‐CoV‐2, 0.44 ± 0.08 mm; P > 0.05). This cross‐sectional analysis revealed higher carotid artery stiffness and aortic stiffness among young adults with SARS‐CoV‐2. These results provide further evidence of cardiovascular impairments among young adults recovering from SARS‐CoV‐2 infection, which should be considered for cardiovascular complications associated with SARS‐CoV‐2.

Maternal arterial stiffness in hypertensive pregnancies with and without small-for-gestational-age neonate.

Pregnancies complicated by pre-eclampsia with a small-for-gestational-age (SGA) neonate have poorer maternal hemodynamic function compared to those with hypertensive disorders of pregnancy (HDP) and an appropriately grown neonate. Arterial stiffness is a recognized prognostic marker of cardiovascular disease in the general population. The aim of this study was to compare maternal arterial stiffness between hypertensive pregnancies with, and those without, a SGA neonate and normotensive control pregnancies. This was a prospective cohort study of pregnancies complicated by pre-eclampsia or gestational hypertension and healthy normotensive control pregnancies, presenting to a tertiary referral hospital between January 2012 and May 2018. Maternal arterial stiffness was assessed by aortic pulse-wave velocity (PWV) and aortic augmentation index (AIx), which were recorded using a non-invasive device (Arteriograph®). Maternal and hemodynamic factors were adjusted for using linear regression analysis. Pregnancies with HDP were divided into those that delivered a SGA (birth weight < 10th percentile) neonate (HDP + SGA group) and those that delivered an appropriately grown neonate (HDP-only group). Comparisons between groups were carried out using the Mann-Whitney U-test for continuous variables and the chi-square (or Fisher's exact) test for categorical variables. Included in the analysis were 69 patients with HDP who delivered a SGA neonate, 129 with HDP who delivered a normally grown neonate and 220 healthy controls. Maternal age, weight, height and heart rate were associated significantly with brachial and aortic AIx. Maternal weight, height, mean arterial pressure, heart rate and gestational age were significant predictors of aortic PWV. Adjusted aortic AIx was significantly higher in both the HDP + SGA and HDP-only groups, compared with in controls (12.5% and 10.0% vs 7.6%; both P < 0.01), and was significantly different between the two HDP groups (P = 0.002). Adjusted PWV was significantly higher in the HDP-only group compared with in controls and the HDP + SGA group (7.7 m/s vs 7.1 m/s and 7.1 m/s; both P < 0.001). Conversely, unadjusted PWV was not significantly different between the two HDP groups (P = 0.414). Pregnancies complicated by HDP with, and those without, a SGA neonate have significantly higher aortic AIx compared with uncomplicated normotensive pregnancies. Aortic AIx was highest in those pregnancies complicated by HDP with a SGA neonate, reflecting a progression in severity of arterial stiffness abnormality with a worsening clinical picture. These findings most likely reflect systemic reduced vascular compliance and increased systemic vascular resistance in pregnancy complicated by HDP. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Aortic Augmentation Index is Dependent on Bodyside in Healthy Young Subjects

Aortic augmentation index (AIx) is a commonly used measure to evaluate the arterial stiffness of large elastic arteries. It has been used as an indicator for cardiovascular risk in clinical practice. To evaluate the difference in the aortic AIx assessed from the left and the right hand in a group of healthy young adults using SphygmoCor and Arteriograph devices. 32 subjects were enrolled in this study (27 ± 7years), 16 male and 16 female volunteers participated. Equally, half of the gender groups were left-handed and another half right-handed. It was found that the aortic AIx values assessed from the pressure waveforms of the right and the left hand are different and significantly higher in the left hand. Using a SphygmoCor device, the mean difference between the aortic AIx values from the right and the left hand among the whole study group was found - 4.78 ± 4.31% and using an Arteriograph the aortic AIx values were - 3.92 ± 3.90%. Aortic AIx values assessed from the right and the left hand were linearly related to each other for both devices. Moreover, it was found that the values of the aortic. AIx are independent of the subject's handedness. It has to be pointed out that subjects who cannot be subjected to assessment of the aortic AIx from one side of the body could have different AIx values estimated from the recorded pressure waveform from the other bodyside.

The serum sclerostin level is positively associated with the aortic augmentation index in patients on peritoneal dialysis.

Objective:Sclerostin is a canonical Wingless (Wnt)/β-catenin signaling pathway inhibitor and had been associated with high arterial stiffness in patients with chronic kidney disease. The aortic augmentation index (AIx), a noninvasive method of assessing central hemodynamics/wave reflections, has been widely used as a clinical index of arterial stiffness. The aim of this study was to evaluate the relationship between fasting serum sclerostin levels and AIx values in peritoneal dialysis (PD) patients.Materials and Methods:Fasting blood samples were obtained from 75 PD patients. The aortic AIx value was measured using a validated tonometry system (SphygmoCor, AtCor Medical, Sydney, New South Wales, Australia). Serum sclerostin and dickkopf-1 (DKK1) levels were quantified using commercial enzyme-linked immunosorbent assay kits.Results:Women PD patients had higher aortic AIx values than men (P = 0.039), while lower aortic AIx values were found in PD patients who used statins (P = 0.004). Univariate linear analysis of the aortic AIx values in PD patients showed that systolic blood pressure (P = 0.001), diastolic blood pressure (P = 0.018), and serum sclerostin levels (P = 0.001) were positively correlated, while height (P = 0.018), body weight (P = 0.001), body mass index (P = 0.043), and weekly total creatinine clearance (P = 0.015) were negatively correlated with aortic AIx values in PD patients. Multivariate linear regression analysis of the factors significantly associated with the aortic AIx values showed that serum sclerostin levels (adjusted R2 = 0.057, P = 0.011) and systolic blood pressure (adjusted R2 = 0.125, P = 0.004) were positively associated, while body weight (adjusted R2 = 0.113, P = 0.002) was inversely associated with aortic AIx values in PD patients.Conclusion:In this study, the serum sclerostin level, but not DKK1, was positively associated with aortic AIx values in PD patients.

Positive correlation of the serum angiopoietin-like protein 3 levels with the aortic augmentation index in patients with coronary artery disease.

PurposeAngiopoietin-like protein 3 (ANGPTL3) plays an important role in lipid metabolism and angiogenesis and is elevated in familial hypercholesterolemia, metabolic syndrome, and insulin resistance. This study aims to evaluate the relationship between the fasting serum ANGPTL3 levels and the aortic augmentation index (AIx) in patients with coronary artery disease (CAD).Materials and methodsFasting blood samples were obtained from 100 patients with CAD. The AIx was measured using a validated tonometry system (SphygmoCor). The serum ANGPTL3 levels were assessed using a commercial enzyme-linked immunosorbent assay kit.ResultsThe aortic AIx values were higher in female patients with CAD (P=0.003) than those in male patients with CAD. The univariate linear analysis of the aortic AIx values reveals that the height (r=−0.363; P<0.001) and body weight (r=−0.350; P<0.001) were negatively correlated, whereas the age (r=0.202; P=0.044) and logarithmically transformed ANGPTL3 (log-ANGPTL3, r=0.357; P<0.001) were positively correlated with the aortic AIx values in patients with CAD. The multivariate forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx revealed that the height (β=−0.269; adjusted R2 change=0.123; P=0.007) and serum log-ANGPTL3 level (β=0.259; adjusted R2 change=0.051; P=0.010) were independent predictors of the aortic AIx values in patients with CAD.ConclusionThe fasting serum ANGPTL3 level positively correlated with the aortic AIx values among patients with CAD.

Hyperleptinemia is associated with the aortic augmentation index in kidney transplant recipients.

Objective:Increased circulating leptin, a marker of leptin resistance, is common in patients with obesity and is also an independent factor in prediction of cardiovascular disease. The aim of this study was to evaluate the relationship between fasting serum leptin levels and the aortic augmentation index (AIx) in kidney transplant recipients.Materials and Methods:Fasting blood samples were obtained from 70 kidney transplant recipients. The aortic AIx was measured using a validated tonometry system (SphygmoCor). Plasma leptin levels were measured using a commercial enzyme-linked immunosorbent assay kit.Results:Simple linear analysis of the aortic AIx in kidney transplant recipients showed that body fat mass (P = 0.002), diastolic blood pressure (DBP) (P = 0.020), logarithmically transformed triglycerides (P = 0.035), and leptin (P < 0.001) were positively correlated, while height (P = 0.004) and the glomerular filtration rate (P = 0.022) were negatively correlated with the aortic AIx in kidney transplant recipients. Forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx showed that leptin (P < 0.001), DBP (P = 0.014), and body height (P = 0.036) were independent predictors of the aortic AIx in kidney transplant recipients.Conclusion:These results suggest that the serum fasting leptin level is associated with the aortic AIx in kidney transplant recipients.

Arterial stiffness in symptomatic smokers with normal lung function.

Chronic obstructive pulmonary disease (COPD) is associated with cardiovascular morbidity and mortality. Arterial stiffness and endothelial dysfunction index are validated surrogate cardiovascular markers and are increased in subjects with COPD.We tested whether increased arterial stiffness and endothelial dysfunction occur in symptomatic smokers with no evidence of bronchial obstruction. Clinical and lung functional assessments were conducted in smoker subjects with chronic respiratory symptoms and in COPD patients. Pulse wave velocity (PWV), aortic augmentation index (AIx) and reactive hyperaemia index (RHI) were measured to estimate the cardiovascular risk.48 smokers (male n=37, female n=11; mean age 70±8.4 years) were studied. Smokers with respiratory symptoms without bronchial obstruction (n=13) did not differ from COPD patients (n=35) in terms of mean±sd PWV (12±3.2 m·s−1 versus 14±3.8 m·s−1; p=0.10), aortic AIx (25.2±11.8% versus 24.8±9.7%, p=0.89) and RHI (1.66±1.49 versus 1.62±1.43; p=0.79).The current investigation shows that the cardiovascular risk occurs in smokers with respiratory symptoms in the absence of bronchial obstruction. These findings need to be confirmed in larger populations in order to inform the design of intensive preventive programmes.

Effects of acute dietary nitrate supplementation on aortic blood pressure and aortic augmentation index in young and older adults

PurposeAging is associated with elevated blood pressure (peripheral and aortic; BP) and aortic augmentation index (AIx) which may contribute to aortic BP. Although inorganic nitrate consumption reduces peripheral BP in both young and older adults, the effects of nitrate consumption on aortic BP and wave reflection in young and older adults is unknown. Therefore, we sought to characterize the effects of nitrate consumption on aortic BP and AIx in young and older adults. MethodsNoninvasive aortic pressure waveforms were synthesized from high-fidelity radial pressure waveforms via applanation tonometry before and following (60, 90, 120, 150, and 180 min) consumption of a nitrate-rich beetroot juice in 26 healthy adults (young: 25 ± 4 years, n = 14; older: 64 ± 5 years, n = 12). Aortic BP and indices of aortic wave reflection (AIx and AIx normalized for heart rate; AIx@75bpm) were calculated from the generated aortic pressure waveform. ResultsNitrate consumption increased plasma nitrite in both groups 60–180 min following beetroot consumption (P < 0.001). Nitrate consumption reduced peripheral and aortic BP in both young and older adults (P < 0.05), with the change being similar between age groups. Conversely, indices of aortic wave reflection were reduced only in young adults following nitrate consumption (range of change from baseline over time: AIx@75bpm, −4.3 to −8.8%, P < 0.05), whereas aortic AIx remained unchanged in the older adults. ConclusionsTaken together, our results suggest that acute dietary nitrate supplementation reduces peripheral and aortic BP similarly in young and older adults despite differential effects on aortic AIx between age groups.

Serum osteoprotegerin levels associated with the aortic augmentation index in renal transplant recipients

ObjectivesArterial stiffness is recognized as an independent risk factor for cardiovascular morbidity and mortality. Recent studies found that osteoprotegerin (OPG) is associated with arterial stiffness and may reflect endothelial dysfunction. The aim of this study was to evaluate the relationship between fasting serum OPG levels and the aortic augmentation index (AIx) in renal transplant recipients. Materials and methodsFasting blood samples were obtained from 66 renal transplant recipients. The aortic AIx was measured using a validated tonometry system (SphygmoCor). Serum OPG levels were measured using a commercial enzyme-linked immunosorbent assay kit. ResultsUnivariate linear analysis of the aortic AIx in renal transplant recipients revealed that body fat mass (r = 0.377, p = 0.002), aortic diastolic blood pressure (DBP; r = 0.307, p = 0.020), triglycerides (r = 0.260, p = 0.035), and logarithmically transformed OPG (log-OPG, r = 0.402, p < 0.001) were positively correlated, whereas height (r = 0.361, p = 0.004) and body weight (r = 0.212, p = 0.041) were negatively correlated with the aortic AIx in renal transplant recipients. Multivariate forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx showed that log-OPG (R2 = 0.213, p < 0.001), height (R2 = 0.081, p = 0.009), and aortic DBP (R2 = 0.058, p = 0.022) were independent predictors of the aortic AIx in renal transplant recipients. ConclusionThese results suggest that the serum fasting OPG level is associated with the aortic AIx in renal transplant recipients.

FP862SERUM OSTEOPROTEGERIN LEVELS ASSOCIATED WITH AORTIC AUGMENTATION INDEX IN RENAL TRANSPLANT RECIPIENTS

Objectives: Arterial stiffness is recognized as an independent risk factor for cardiovascular morbidity and mortality. Recent studies found that osteoprotegerin (OPG) is associated with arterial stiffness and may reflect endothelial dysfunction. The aim of this study was to evaluate the relationship between fasting serum OPG levels and the aortic augmentation index (AIx) in renal transplant recipients. Materials and methods: Fasting blood samples were obtained from 66 renal transplant recipients. The aortic AIx was measured using a validated tonometry system (SphygmoCor). Serum OPG levels were measured using a commercial enzyme-linked immunosorbent assay kit. Results: Univariate linear analysis of the aortic AIx in renal transplant recipients revealed that body fat mass (r 1⁄4 0.377, p 1⁄4 0.002), aortic diastolic blood pressure (DBP; r 1⁄4 0.307, p 1⁄4 0.020), triglycerides (r 1⁄4 0.260, p 1⁄4 0.035), and logarithmically transformed OPG (log-OPG, r 1⁄4 0.402, p < 0.001) were positively correlated, whereas height (r 1⁄4 0.361, p 1⁄4 0.004) and body weight (r 1⁄4 0.212, p 1⁄4 0.041) were negatively correlated with the aortic AIx in renal transplant recipients. Multivariate forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx showed that log-OPG (R2 1⁄4 0.213, p < 0.001), height (R2 1⁄4 0.081, p 1⁄4 0.009), and aortic DBP (R2 1⁄4 0.058, p 1⁄4 0.022) were independent predictors of the aortic AIx in renal transplant recipients. Conclusion: These results suggest that the serum fasting OPG level is associated with the aortic AIx in renal transplant recipients. Copyright © 2016, Buddhist Compassion Relief Tzu Chi Foundation. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).

Correlation between arterial wall stiffness, N-terminal prohormone of brain natriuretic peptide, functional and structural myocardial abnormalities in patients with type 2 diabetes mellitus and cardiac autonomic neuropathy

Aim. To assess arterial wall stiffness, plasma levels of of N-terminal prohormone of brain natriuretic peptide (NT-proBNP), as well as functional state and structure of the myocardium in patients with type 2 diabetes mellitus (T2DM) and cardiac autonomic neuropathy (CAN). Materials and Methods. The study involved a total of 65 patients with T2DM. 12 had no evidence of cardiovascular disease (CVD) or CAN, 14 were diagnosed with subclinical stage of CAN, 18 ? with functional stage, and 21 ? with organic stage. We measured aortic pulse wave velocity (PWV), aortic augmentation index (AIx), brachial artery AIx, ambulatory arterial stiffness index (AASI) and plasma levels of NT-proBNP. Clinical examination included ECG, Holter monitoring, ambulatory BP measurement and echocardiography. Results. Patients with isolated T2DM showed a trend for increased vascular wall stiffness. PWV was increased in patients with subclinical stage of CAN. Aortic and brachial AIx, PWV and AASI were elevated in patients with functional stage of CAN, PWV being significantly higher vs. subclinical CAN subgroup. Organic stage was characterized by pathologically increased values of all primary parameters; PWV and AASI were significantly higher compared with other groups. Development and progression of CAN was accompanied by an increase in NT-proBNP plasma levels. Concentration of NT-proBNP was in direct correlation with left ventricular mass (LVM) and PWV. PWV and LVM values also directly correlated between themselves. Conclusion. Development and progression of CAN in patients with T2DM is accompanied by an increase in vascular wall stiffness. The elevation of plasma NT-proBNP in patients with T2DM correlates with the development of CAN and is significantly and independently associated with an increase in LVM and PWV. Our data suggests the pathophysiological interconnection between metabolic, functional and structural myocardial abnormalities in patients with T2DM and CAN.

Heritability of arterial stiffness and carotid intima-media thickness: An Italian twin study

Carotid intima-media thickness (IMT) and arterial stiffness parameters, including aortic augmentation index (AIx) and pulse wave velocity (PWV), are independent predictors of stroke and cardiovascular disease. Genetic effects on these traits were never explored in a Mediterranean country. The present study aims to quantify the contribution of genes, environment and age to carotid IMT and aortic Aix and PWV. The twin design was used. A total of 348 adult twins from the Italian Twin Register underwent measurements of carotid IMT and aortic PWV and AIx in three university hospitals located in Rome, Padua and Perugia. Carotid IMT was measured by B-mode ultrasound, aortic PWV and AIx by Arteriograph. Genetic modelling was performed to decompose total variance of traits into genetic, shared and unshared environmental and age components. For each phenotype, the best-fitting model included additive genetic, unshared environmental and age effects. For IMT, heritability was 0.32 (95% confidence interval (CI): 0.25-0.38), unshared environmental component was 0.25 (0.18-0.32) and age contribution was 0.44 (0.39-0.49). For AIx and PWV, heritabilities were 0.42 (0.29-0.55) and 0.49 (0.35-0.62), unshared environmental components were 0.31 (0.22-0.44) and 0.37 (0.26-0.51) and age contributions were 0.27 (0.16-0.39) and 0.14 (0.06-0.24), respectively. This study shows substantial genetic and unshared environmental influences on carotid intima-media thickness and arterial stiffness and confirms the relevant role of age in the aetiology of these traits. Further support is provided for prevention and health promotion strategies based on modifiable factors.

PM.04 Cardiovascular Indices in the Early Identification of Pre-Eclampsia in Women at High-Risk For Hypertensive Disorders of Pregnancy

ObjectiveBiochemical markers such as PlGF have been proposed as point-of-care tests for the early identification of women at risk of hypertensive disorders. The aim of this study was to ascertain...

Arterial Stiffness and Pulse Wave Reflection in Young Adult Heterozygous Sickle Cell Carriers

Objective: Pulse wave velocity (PWV) and aortic augmentation index (AI) are indicators of arterial stiffness. Pulse wave reflection and arterial stiffness are related to cardiovascular events and sickle cell disease. However, the effect of these parameters on the heterozygous sickle cell trait (HbAS) is unknown. The aim of this study is to evaluate the arterial stiffness and wave reflection in young adult heterozygous sickle cell carriers.Materials and Methods: We enrolled 40 volunteers (20 HbAS cases, 20 hemoglobin AA [HbAA] cases) aged between 18 and 40 years. AI and PWV values were measured by arteriography.Results: Aortic blood pressure, aortic AI, and brachial AI values were significantly higher in HbAS cases compared to the control group (HbAA) (p=0.033, 0.011, and 0.011, respectively). A statistically significant positive correlation was found between aortic pulse wave velocity and mean arterial pressure, age, aortic AI, brachial AI, weight, and low-density lipoprotein levels (p=0.000, 0.017, 0.000, 0.000, 0.034, and 0.05, respectively) in the whole study population. Aortic AI and age were also significantly correlated (p=0.026). In addition, a positive correlation between aortic PWV and systolic blood pressure and a positive correlation between aortic AI and mean arterial pressure (p=0.027 and 0.009, respectively) were found in HbAS individuals. Our study reveals that mean arterial pressure and heart rate are independent determinants for the aortic AI. Mean arterial pressure and age are independent determinants for aortic PWV. Conclusion: Arterial stiffness measurement is an easy, cheap, and reliable method in the early diagnosis of cardiovascular disease in heterozygous sickle cell carriers. These results may depend on the amount of hemoglobin S in red blood cells. Further studies are required to investigate the blood pressure changes and its effects on arterial stiffness in order to explain the vascular aging mechanism in the HbAS trait population. Conflict of interest:None declared.

Aortic Augmentation Index is Independently Associated With N-Terminal Pro B-type Natriuretic Peptide in Patients With Peripheral Arterial Disease

To investigate the relationship of aortic augmentation index (AIx) with N-terminal pro B-type natriuretic peptide (NTproBNP) plasma levels in patients with peripheral arterial disease (PAD) with normal left ventricular (LV) function. Totally, 31 patients (23 males, mean age 65 ± 7.4) with a confirmed diagnosis of PAD of the lower limbs (ankle-brachial pressure index [ABPI] <0.90 in at least 1 leg) were enrolled in this study. All patients underwent pulse wave analysis by applanation tonometry of the radial artery using the SphygmoCor system and had a measurement of plasma NTproBNP levels. Patients had a mean resting ABPI of 0.62 ± 0.19 and a mean AIx 32.6% ± 6.9. Median (interquartile range) NTproBNP plasma level was 75 (44-210) pg/mL. In a univariate analysis which included age, brachial systolic blood pressure (BSBP), brachial diastolic blood pressure (BDBP), ejection duration index (ED%), heart rate (HR), and NTproBNP, aortic AIx was significantly associated (Spearman rho) with NTproBNP, HR, and ED% (r = .49, P = .006; r = -.72, P = .000, and r = -.42, P = .02, respectively). Multivariate linear regression analysis showed that AIx was associated with NTproBNP (β = 0.38, P = .02) independent of gender, HR, ED%, and use of β-blockers. N-terminal pro B-type natriuretic peptide explained 8% of the variance in aortic AIx, whereas HR explained 15% of the variance. In patients with PAD with normal LV systolic function, AIx is independently associated with NTproBNP. Structural changes in the myocardium might occur due to increased LV afterload as a result of increased wave reflections and arterial stiffness due to atherosclerosis leading to an increase in NTproBNP plasma levels.

Abstract 535: Effects of Short-term Exercise-Training on Aortic Stiffness and Central Blood Pressure in Young-to-Middle Aged Pre- or Grade I Hypertensives.

Aim: To assess the effects of 6-weeks of exercise-training and a period of detraining on aortic stiffness and central aortic blood pressure (BP) in young-to-middle-aged pre- and grade I hypertensives. Methods: Thirty-five sedentary or recreationally active men and women (30-57years) with untreated pre- or stage I hypertension completed 6-weeks of continuous moderate intensity (Mod Ex)(n=20) or high intensity interval (High Ex)(n=15) exercise-training (at least 3 days/week, on a stationary bike and/or treadmill) and a 3-week detraining period. Carotidfemoral pulse wave velocity (PWV), aortic augmentation index (AIx), central aortic BP (SphygmoCor) and brachial BP were determined before and after exercise-training and after 3-weeks of detraining. Results: Peak oxygen consumption increased from 26.5 to 28.7ml.kg-1.min-1 and from 27.0 to 29.3ml.kg-1.min-1 after 6-weeks of Mod or High Ex respectively (p&lt;0.05). Mod Ex decreased brachial systolic (SBP) and diastolic BP from 141±9/93±7mmHg to 132±10/83±13mmHg (p&lt;0.05) and these values returned to hypertensive/prehypertensive levels after detraining (146±8/92±10mmHg). Neither PWV (baseline: 4.79±0.96m/sec; after 6-weeks training: 4.99±1.00m/sec), AIx (Baseline: 25.5±10.0%; after 6-weeks training: 22.1±11.6%), nor aortic pulse pressure were modified by Mod Ex. Although aortic SBP decreased after 6-weeks of Mod Ex (p&lt;0.05) and returned to baseline values after 3-weeks of detraining, these changes were accounted for by decreases in mean arterial pressure. High Ex did not modify brachial or aortic BP, PWV or AIx. Conclusions: In young-to-middle-aged pre- or grade I hypertensives, although short-term moderate intensity exercise-training may decrease aortic BP, these effects are not attributed to alterations in the properties of the aorta.

Radial augmentation index and diabetic complications in patients with type 2 diabetes mellitus

Background Increased arterial stiffness is associated with cardiovascular diseases. Aortic augmentation index (AI) depends on arterial stiffness, although its relation with diabetic complications was not fully understood. Using radial AI as a surrogate index for aortic AI, we studied the relationship between radial AI and diabetic micro- and macroangiopathy in patients with type 2 diabetes mellitus.

The potent calcitonin gene‐related peptide receptor antagonist, telcagepant, does not affect nitroglycerin‐induced vasodilation in healthy men

To assess the effect of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, on the haemodynamic response to sublingual nitroglycerin (NTG). Twenty-two healthy male volunteers participated in a randomized, placebo-controlled, double-blind, two-period, crossover study. Subjects received 500 mg telcagepant or placebo followed, 1.5 h later, by 0.4 mg NTG. To assess the haemodynamic response the following vascular parameters were measured: blood pressure, aortic augmentation index (AIx) and brachial artery diameter (BAD). Data are presented as mean (95% confidence interval, CI). The aortic AIx following NTG decreased by -18.50 (-21.02, -15.98) % after telcagepant vs. -17.28 (-19.80, -14.76) % after placebo. The BAD fold increase following NTG was 1.14 (1.12, 1.17) after telcagepant vs. 1.13 (1.10, 1.15) after placebo. For both AIx and BAD, the hypothesis that telcagepant does not significantly affect the changes induced by NTG is supported (P < 0.0001). In addition, no vasoconstrictor effect of telcagepant could be demonstrated. Telcagepant did not affect NTG-induced haemodynamic changes. These data suggest that NTG-induced vasodilation is not CGRP dependent.