Central Aortic Systolic Pressure Research Articles

Central Aortic Blood Pressure and Management of Hypertension

See related article, pp 1138–1145 Hypertension, a condition of elevated arterial blood pressure (BP) conventionally diagnosed by brachial cuff sphygmomanometry, is associated with increased risk of cardiovascular mortality and morbidity and end-organ damage. However, the marked differences in pulse pressure between the central aorta and peripheral limbs1 suggest that effects of peak values of arterial BP (eg, systolic BP) on centrally located organs (heart, brain, kidney) may not be accurately assessed using peripheral measurements. Our early studies2 showed substantial difference in the effects of sublingual nitroglycerin on peripheral and central (carotid) pulse pressures: in some cases, central systolic BP decreasing ≤20 mm Hg with little or no effect on brachial or radial systolic BP. There were, however, marked changes in the pulse wave form.2 The relationship between central aortic and radial pressure waves, quantified in terms of a mathematical transfer function, has been validated to be applicable across a large range of physiological pressures.3 The use of this noninvasive technique (and other variations, including other forms of analysis of the radial pulse or direct registration of the carotid pulse) has facilitated a large number of studies highlighting the differential effects of antihypertensive therapy on central aortic systolic BP for similar values of brachial cuff systolic BP.4 A seminal study by McEniery et al5 in >10 000 subjects demonstrated a substantial overlap of central and brachial BP between categories of hypertension. Approximately 32% of men and 10% of women who would be considered to have normal brachial systolic BP (and therefore, not treated) would be classified as having stage 1 hypertension based on equivalent central aortic systolic BP. Indeed, the implications of these findings suggested a possible sign of a paradigm shift in the management and treatment of hypertension as a significant cardiovascular risk.6 Subsequent studies …

Effects of the DPP-4 inhibitor saxagliptin on early vascular changes in the retinal and systemic circulation

In type-2 diabetes early vascular changes (among others) are hyperperfusion in the retinal circulation (like in the kidney) and increased pulse wave reflection leading to increased aortic pressure. We analyzed whether the DPP4-inhibitor saxagliptin reverses early vascular and haemodynamic changes in type-2 diabetes. In this double-blind randomized controlled clinical cross-over trial 42 patients with type-2 diabetes (age 60.3, 13 were females, BMI 30.6 kg/m2, mean duration of diabetes 4 years, HbA1c 7.0%, blood pressure 132/79 mmHg) were consecutively [PB1] included and randomized to placebo or saxagliptin 5 mg for 6 weeks each. Retinal capillary flow (RCF) was assessed at baseline and after flickerlight exposure (as a vasodilatory test) by scanning laser Doppler flowmetry. Central (aortic) systolic blood pressure (SBP), central pulse pressure (PP), augmentation index and pulse wave velocity were determined with the SphygmoCor device. Following treatment with saxagliptin (as opposed to placebo) saxagliptin effected a better glycemic control, a reduced retinal capillary flow (p=0.033) and, in parallel, reduced central systolic augmentation and pulse pressure (see table). In accordance, Flicker light induced increment of RCF (indicative of vasodilatory capacity of the retinal circulation) was numerically 2-fold greater, although not significant. View this table: Table 1 Our data suggest that treatment with saxagliptin for 6 weeks normalizes retinal capillary flow and improves central haemodynamics in type 2 diabetes.

人体动脉血管的粘性流体力学模型与中心动脉血压估计

It becomes a common understanding that central aortic systolic and/or pulse pressures (CAP) provide direct and accurate prediction for cardiovascular structural damage and cardiovascular outcomes. Existing methods for CAP measurement and estimation, namely, method based on general transfer function, and N-point moving averaging method, are rather empirical, and lack of theoretical foundation. Those methods also have inherent drawback that there are not personalized, and missing individual aortic characteristics. Here in this paper, we present a novel method of model-based central aortic pressure measurement and computing, referred to as MCAP. MCAP has solid theoretical foundation; a novel human aortic network model is proposed and developed based on viscous fluid mechanics theory. In MCAP, model parameters of individuals are computed from measured pulse wave of radial artery and brachial artery, the central aortic - radial artery transfer function is derived from the model, and finally, the central aortic pressure and pulse wave are obtained. We conducted an experiment at Cardiovascular Department of Beijing Hospital. Experimental results on 50 test cases have shown better performance of MCAP with comparison to GTF and N-point average method ( r MCAP = 0:9667, r GTF = 0:9025, r NPMA = 0:8099). The MCAP accuracy (Mean(SBP/DBP) =3.9 mmHg/3.6 mmHg, Stdev (SBP/DBP) = 7.7 mmHg/2.9 mmHg) of central artery systolic pressure and diastolic pressure is up to the standard of AAMI (Mean≤65 mmHg, Stdev≤68 mmHg).

Tonometric devices for central aortic systolic pressure measurements in patients with type 1 diabetes

Central blood pressure may be a better risk marker than brachial blood pressure and can be measured noninvasively by tonometric devices. We investigate whether tonometric measurements are feasible in patients with diabetes and whether the degree of albuminuria or increased arterial stiffness affects measurements. In 676 patients with type 1 diabetes, comparison of central aortic systolic pressure (CASP) measurements by the BPro and the SphygmoCor devices were made. The BPro device can obtain both office and 24-h measurements, whereas the SphygmoCor device is an accepted device for CASP measurements. Measurements of CASP with both BPro and SphygmoCor were available in 598 (88.5%) patients (mean age 54 years; mean diabetes duration 33 years; 45.2% women), and mean±SD of CASP was 122±17 and 118±17 mmHg, respectively (P<0.001). Linear and intraclass correlation coefficients between CASP estimated from BPro and SphygmoCor were r equal to 0.96 and 0.95 (P<0.001 for both). The mean±SD difference between devices was 3.6±4.8 mmHg (P<0.001).Analyses according to the level of albuminuria or degree of arterial stiffness were confirmatory. In patients with type 1 diabetes, tonometric measurements of CASP with BPro and SphygmoCor showed strong correlations, although values differed by ∼4 mmHg between devices. Level of CASP, arterial stiffness, and degree of albuminuria did not interfere with the agreement between devices.In addition, the BPro device can obtain 24-h measurements and may thus be useful to assess the diurnal patterns of CASP.

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Diverse effects of interdialytic intervals on central wave augmentation in haemodialysis patients

Increased arterial stiffness is a common finding and independent predictor of mortality in end-stage renal disease (ESRD) patients. A long interdialytic interval was associated with increased risk of cardiovascular death in patients receiving conventional haemodialysis (HD). This is the first study to examine the effects of a long (3-day) versus short (2-day) interdialytic period on arterial elasticity in HD patients. Seventy ESRD patients receiving standard HD three times per week were studied at the start and end of a 3-day and a 2-day interdialytic interval. At each time point, applanation tonometry of peripheral arteries was performed to assess arterial stiffness and wave reflection parameters. Aortic and brachial pulse wave velocities (PWV) were recorded as measures of arterial stiffness and augmentation index (AIx) as a measure of wave reflections. AIx, heart-rate-adjusted AIx and augmentation pressure were significantly increased during both interdialytic intervals, whereas aortic and brachial PWVs remained unchanged. The interdialytic increases in all the three AIx parameters were significantly higher during the 3-day interval in comparison to the 2-day interval (P < 0.001 for all comparisons). In contrast, no significant differences in interdialytic changes of aortic (P = 0.355) and brachial (P = 0.319) PWVs were noted between the two intervals. Mixed linear model analysis revealed that central aortic systolic blood pressure (SBP) and body weight, but not aortic or brachial PWV, were independent determinants of the change in heart-rate-adjusted AIx throughout the study. AIx is increased between HD sessions, whereas arterial elasticity is not. This interdialytic increase in central wave augmentation is more pronounced during the 3-day interval, suggesting a mechanism possibly involved in the elevated cardiovascular risk of HD patients at this time point.

A randomized trial of fish oil omega-3 fatty acids on arterial health, inflammation, and metabolic syndrome in a young healthy population

BackgroundLong chain omega-3 fatty acids from fish oils (O3) are known to have beneficial effects on a number of vascular risk factors in at-risk populations. The effects of a highly bioavailable emulsified preparation on an overweight young adult population are less well known.MethodsYoung adults, age 18–30, with body mass indices (BMIs) greater than 23 (average = 28.1) were administered 1.7 g of O3 per day (N = 30) or safflower oil placebo (N = 27) in an emulsified preparation (Coromega, Inc.) for 4 weeks in a double-blind randomized design. Blood was drawn and anthropometric measurements taken before and after dosing. Hemodynamic measures (central pulse wave velocity, augmentation index, and aortic systolic blood pressure), inflammatory cytokines (IL-6, IL-8, IL-10, and tumor necrosis factor-α), red blood cell and plasma phospholipid fatty acid profiles, fasting serum lipids, glucose, and C-reactive protein were measured.ResultsRed cell and plasma phospholipid eicosapentaenoic acid and docosahexaenoic acid concentrations increased over the four weeks of dosing in the O3 group. Dosing with O3 did not affect central pulse wave velocity, augmentation index, or aortic systolic blood pressure. None of the five American Heart Association metabolic syndrome components improved over the dosing period. None of the inflammatory cytokines, C-reactive protein, or lipids (total or LDL cholesterol) improved over the dosing period.ConclusionsNo salutary effects of O3 were observed in hemodynamic, metabolic syndrome criteria or inflammatory markers as a result of this relatively short period of administration in this relatively overweight, but healthy young adult cohort.

Effects of Low-Dose Atorvastatin on Arterial Stiffness and Central Aortic Pressure Augmentation in Patients With Hypertension and Hypercholesterolemia

Experimental and clinical data suggest that statins exert anti-inflammatory and antiproliferative actions on vasculature beyond their lipid-lowering properties. Whether these pleiotropic effects of statins translate into a beneficial effect on arterial stiffness is not clear. This study aimed to evaluate the potential effects of low-dose atorvastatin treatment on arterial stiffness and central arterial pressure waveforms in patients with mild hypertension and hypercholesterolemia. In a double-blind, randomized, placebo-controlled fashion, 50 hypertensive and hypercholesterolemic patients were allocated to receive 10 mg of atorvastatin or placebo for 26 weeks. Arterial stiffness was assessed by aortic pulse-wave velocity (PWV) using a Sphygmocor device. Central arterial pressure waveform parameters were estimated by radial artery applanation tonometry. Heart rate-adjusted augmentation index (AIx(75)) was used as measure of wave reflections. At study end, aortic PWV (9.0 ± 1.5 vs. 10.9 ± 2.6 m/sec; P < 0.001) and AIx(75) (24.9% ± 9.7% vs 28.8% ± 11.8%; P < 0.001) were significantly lower in the atorvastatin group than that placebo group. Furthermore, decreases in central aortic systolic blood pressure and pulse pressure were evident at study-end with atorvastatin but not with placebo (130 ± 8 vs. 138 ± 6 mm Hg, P < 0.001; 48 ± 7 vs. 53 ± 6 mm Hg, P < 0.05, respectively). Atorvastatin-induced reductions in aortic PWV during follow-up showed significant associations with changes in AIx(75) and central aortic systolic blood pressure and pulse pressure. This study shows that low-dose atorvastatin treatment improves arterial stiffness and exerts a reduction on central aortic pressures. These effects may represent a potential mechanism of cardiovascular risk reduction observed with statin use. ClinicalTrials.gov Database Identifier Number: NCT01126684.

24-hour central aortic systolic pressure and 24-hour central pulse pressure are related to diabetic complications in type 1 diabetes – a cross-sectional study

BackgroundNon-invasive measurements of 24 hour ambulatory central aortic systolic pressure (24 h-CASP) and central pulse pressure (24 h-CPP) are now feasible. We evaluate the relationship between 24 h central blood pressure and diabetes-related complications in patients with type 1 diabetes.MethodsThe study was cross-sectional, including 715 subjects: 86 controls (C), 69 patients with short diabetes duration (< 10 years), normoalbuminuria (< 30 mg/24 h) without receiving antihypertensive treatment (SN), 211 with longstanding diabetes (≥ 10 years) and normoalbuminuria (LN), 163 with microalbuminuria (30-299 mg/24 h) (Mi) and 186 with macroalbuminuria (> 300 mg/24 h) (Ma).24 h-CASP and 24 h-CPP was measured using a tonometric wrist-watch-like device (BPro, HealthStats, Singapore) and derived using N-point moving average.ResultsIn C, SN, LN, Mi and Ma mean ± SD 24 h-CASP was: 114 ± 17, 115 ± 13, 121 ± 13, 119 ± 16 and 121 ± 13 mmHg (p < 0.001); and 24 h-CPP: 38 ± 8, 38 ± 7, 44 ± 10, 46 ± 11 and 46 ± 11 mmHg, (p < 0.001).Following rigorous adjustment (24 h mean arterial pressure and conventional risk factors), 24 h-CASP and 24 h-CPP increased with diabetes, albuminuria degree, previous cardiovascular disease (CVD), retinopathy and autonomic dysfunction (p ≤ 0.031).Odds ratios per 1 standard deviation increase in 24 h-CASP, 24 h-CPP and 24 h systolic blood pressure (24 h-SBP) were for CVD: 3.19 (1.68-6.05), 1.43 (1.01-2.02) and 2.39 (1.32-4.33), retinopathy: 4.41 (2.03-9.57), 1.77 (1.17-2.68) and 3.72 (1.85-7.47) and autonomic dysfunction: 3.25 (1.65-6.41), 1.64 (1.12-2.39) and 2.89 (1.54-5.42).Conclusions24 h-CASP and 24 h-CPP was higher in patients vs. controls and increased with diabetic complications independently of covariates. Furthermore, 24 h-CASP was stronger associated to complications than 24 h-SBP.The prognostic significance of 24 h-CASP and 24 h-CPP needs to be determined in follow-up studies.Trial registrationClinicalTrials.gov ID NCT01171248.

Augmentation index as a specific marker of large arteries distensibility

lthough high blood pressure has been undoubtedlyshown to be a major risk factor for cardiovascularmorbidity and mortality at all ages and in bothsexes, the suitability and accuracy of traditional bloodpressure measurements for cardiovascular risk staging isnow a matter of lively debate [1]. In this context, thepossible additional contribution carried by central bloodpressure values assessment and by pulse wave analysis hasbeen underlined by a number of studies [2,3].Indeed, the technique of pulse wave analysis, usingnoninvasive high fidelity arterial tonometers, has recentlybecome increasingly popular [4,5]. This method can pro-vide not only quantitative, although indirect, informationconcerning the levels of central blood pressure, but alsoqualitative data on the ascending aortic waveform. Analysisof such waveforms can, in fact, define the elastic propertiesof the arterial wall and can estimate the importance and thetransmission speed of reflected waves [6,7].In the last years, augmentation index (AIx) has beenfrequently used in the context of pulse waveform analysisand has been suggested to represent a parameter able toreliablyreflectthelevelofarterialstiffnessintheassessmentof cardiovascular risk. Assessment of AIx provides anindication of the role played by reflected waves in deter-mining pulse pressure. The contribution of the backwardwave to pulse pressure is related to the timing of its super-imposition onto the forward wave, as well as to its magni-tude and shape. AIx is calculated as the ratio between theaugmented central pressure, due to reflected waves, andpulse pressure. Conditions of markedly increased arterialstiffness are characterized by an early superimposition ofbackward waves onto the forward wave, causing anincrease in central SBP. Assessment of AIx has, thus, beenproposedasasimpleapproachtoquantifytheroleofwavereflection in determining an elevation of central bloodpressure values.However, it has to be acknowledged that several otherfactors, apart from the viscoelastic properties of the aortaand of large arteries [8], may affect AIx, in particular: themagnitude and variability of reflected waves, mainly inrelation to systemic vascular resistance; the length of theaorta (related to an individual’s height), because at anygiven level ofarterial distensibility, thenearer the reflectionsites are to the ascending aorta, the shorter is the timeneeded for the reflected wave to reach it; the participant’sheart rate, an increase in heart rate being accompanied byanincreaseinpulsewavevelocity,butalsobyadecreaseinaugmented pressure [3], that is in AIx; the phenomenon ofpressure waves attenuation while travelling along the arte-rial tree; and the role of gender, several studies havingshown significantly higher values of AIx in female than inmale individuals of comparable height (Fig. 1).Thus, given the contribution of several factors to AIxmagnitude, use of this parameter as a specific index of theviscoelastic properties of large arteries is incorrect and maylead to inaccurate estimates. In fact, in clinical practice it isnot uncommon to find a marked discrepancy betweenpulse wave velocity (considered as the gold standardmarker of arterial distensibility [9]) and AIx values, whichmay indeed be due to the multiple factors involved indetermining the latter parameter.The article by Cheng et al. [10], published in this issue ofthe Journal of Hypertension, was aimed at exploringthe potential contribution of cardiac motion and arterialproperties, respectively, to arterial pressure waveformparameters, in particular to AIx.The conclusion of this study is that AIx may not bepredominantly determined by arterial properties, but, onthe contrary, it largely depends on left ventricular systolicfunction. Thus, based on these data, the use of AIx as asurrogate index of arterial stiffness might need to be recon-sidered [10].These conclusions are based on data collected in 20healthy male individuals (median age 22.3 years), withoutcardiovascular risk factors and free of chronic diseases. Ithas to be emphasized that although the selective inclusionin this study of a healthy young male cohort has carried theadvantage of minimizing the possible confounding effects

Pressure at the last systolic shoulder of the arterial waveform equals central aortic systolic pressure and is constant along the upper limb

Pressure at the last systolic shoulder of the arterial waveform equals central aortic systolic pressure and is constant along the upper limb

Wave reflection quantification based on pressure waveforms alone—Methods, comparison, and clinical covariates

Within the last decade the quantification of pulse wave reflections mainly focused on measures of central aortic systolic pressure and its augmentation through reflections based on pulse wave analysis (PWA). A complementary approach is the wave separation analysis (WSA), which quantifies the total amount of arterial wave reflection considering both aortic pulse and flow waves. The aim of this work is the introduction and comparison of aortic blood flow models for WSA assessment. To evaluate the performance of the proposed modeling approaches (Windkessel, triangular and averaged flow), comparisons against Doppler measurements are made for 148 patients with preserved ejection fraction. Stepwise regression analysis between WSA and PWA parameters are performed to provide determinants of methodological differences. Against Doppler measurement mean difference and standard deviation of the amplitudes of the decomposed forward and backward pressure waves are comparable for Windkessel and averaged flow models. Stepwise regression analysis shows similar determinants between Doppler and Windkessel model only. The results indicate that the Windkessel method provides accurate estimates of wave reflection in subjects with preserved ejection fraction. The comparison with waveforms derived from Doppler ultrasound as well as recently proposed simple triangular and averaged flow waves showed that this approach may reduce variability and provide realistic results.

Central Hemodynamics in Prehypertension: Effect of the β‐Adrenergic Antagonist Nebivolol

The aim of the current study was to characterize the effects of the novel β-adrenergic antagonist nebivolol on central aortic blood pressures, arterial properties, and nitroxidergic activity in individuals with prehypertension. Prehypertension is emerging as a major risk factor for several adverse cardiovascular consequences. Increased pulse wave velocity, aortic augmentation index, and aortic blood pressures have been linked with augmented risk of cardiovascular disease and mortality. While the effects of antihypertensive drugs on these parameters in hypertensive patients have been studied, there are limited data so far in prehypertension. Fifty individuals with prehypertension were randomized to either nebivolol (5 mg per day) or placebo in a double-blind clinical trial. Patients underwent measurement of pulse wave velocity as well as aortic blood pressure and aortic augmentation index via pulse wave analysis at baseline and 8 weeks. Patients also had blood and urine biochemistries done at each visit. Nebivolol achieved significant reductions in central aortic systolic (P=.011), diastolic (P=.009), and mean arterial blood pressure (P=.002). Pulse wave velocity trended toward improvement but did not achieve significance (P=.088). Nitric oxide production, measured as urinary nitrite/nitrite excretion, also rose substantially in the nebivolol group (by approximately 60%, P=.030). Central blood pressures can be effectively lowered by β-blockade while patients are still in the prehypertension phase, and the effects may be coupled to improve nitric oxide release by the drug.

Central blood pressure: a powerful predictor of the development of hypertension

We examined whether the central aortic systolic blood pressure, a marker of the function of the systemic arterial tree, might be a more powerful predictor of the development of hypertension than the brachial-ankle pulse wave velocity, a marker of the stiffness of the large- to middle-sized arteries, independent of the conventional risk factors for the development of hypertension. In 1268 Japanese men without hypertension (43±8 years old), the relationships between three variables (the second peak of the radial pressure waveform (SP2), brachial-ankle pulse wave velocity and conventional risk factors measured at the first examination) with the presence of hypertension at the second examination (after 3 years' follow-up) were examined. Hypertension was detected at the second examination in 154 men. The best cutoff points of the brachial-ankle pulse wave velocity and SP2, for predicting the development of hypertension, were 12.7 m/s and 109 mm Hg, respectively. The results of a logistic regression analysis confirmed that an SP2 of ≥109 mm Hg (odds ratio=8.493, P<0.001) was a more powerful predictor of the development of hypertension than a brachial-ankle pulse wave velocity of ≥12.7 m/s, independent of the conventional risk factors. The net reclassification index of SP2 (at the best cutoff point) to brachial-ankle pulse wave velocity was 0.211 (P<0.001), indicating that SP2 is a better predictor of the development of hypertension than brachial-ankle pulse wave velocity. In middle-aged Japanese men without hypertension, SP2 may be a more powerful predictor of the development of hypertension than the assessment of stiffness in large to middle-sized arteries independent of the conventional risk factors.

Central and peripheral blood pressure profile of young offspring with hypertensive and normotensive parents

In this cross-sectional study we compared the central aortic systolic pressure (CASP), peripheral brachial systolic pressure (PSP), peripheral brachial diastolic pressure (PDP) and augmentation index (AIx) between normotensive offspring of nonhypertensive parents (ONT) and normotensive offspring with at least one hypertensive parent (OHT). A total of 100 healthy ONT (mean age 20.95 ± 2.06) and 100 healthy OHT (mean age 20.89 ± 2.12) individuals were recruited. Parental history of hypertension was determined by detailed history taking. CASP, PSP, PDP and AIx were measured using the BPro device. All blood pressure (BP) measurements were calibrated using oscillometric BP readings. The OHT group had higher PSP (117.57 ± 10.06 versus 114.52 ± 8.94, P < 0.05), PDP (72.39 ± 7.28 versus 70.39 ± 6.50, P < 0.05) and CASP (103.72 ± 8.95 versus 101.37 ± 7.74, P < 0.05) compared to the ONT group. There was no significant difference in AIx in the ONT group (57.97 ± 11.02 versus 58.08 ± 12.16, P = 0.95) in comparison to the OHT group. However, following adjustments for certain cardiovascular risk factors, only PSP (117.33 versus 114.76, P < 0.05) remained significantly higher in the OHT group compared to the ONT group. Analysis of adjusted data within sex showed that CASP was higher in the female OHT group compared to the female ONT group, whereas PDP were higher in the male OHT group compared to the male ONT group. Alterations in PSP, PDP and CASP are already present in early life in normotensive offspring of hypertensive parents, with possible differences in mechanism between different sexes.

Maternal Hemodynamics in Normal Pregnancies at 11–13 Weeks’ Gestation

Objective: In women with established pre-eclampsia and gestational diabetes there is an increase in central aortic systolic blood pressure (SBP_Ao), pulse wave velocity (PWV) and augmentation index (AIx), which are measures of arterial stiffness. The aim of this study was to establish normal ranges for PWV, AIx and SBP_Ao at 11–13 weeks’ gestation and to examine the maternal characteristics which affect these parameters. Methods: This was a prospective study in singleton pregnancies at 11⁺⁰–13⁺⁶ weeks’ gestation. Maternal history and characteristics were recorded and PWV, AIx and SBP_Ao were measured. Multiple regression analysis was used to examine which of the maternal characteristics provided a significant contribution in the prediction of Alx-75, PWV and SBP_Ao. Results: In normal pregnancies PWV, AIx-75 and SBP_Ao were related to certain maternal characteristics, including increase with maternal age for AIx-75 and PWV, decrease with maternal height for AIx-75 and increase with maternal weight for PWV and SBP_Ao and decrease for AIx (p < 0.0001). The median, 5th, 10th, 90th and 95th percentiles for AIx-75 MoM (multiple of the unaffected median), PWV MoM and SBP_Ao MoM were 1.00, 0.72, 0.79, 1.34 and 1.48; 1.00, 0.77, 0.82, 1.24 and 1.33; and 1.00, 0.86, 0.88, 1.15 and 1.20, respectively. Conclusions: This study provides normal ranges for PWV, AIx and SBP_Ao at 11–13 weeks’ gestation and defines the maternal characteristics which affect these vascular parameters.

Improvement in arterial stiffness following cardiac rehabilitation

BackgroundExercise has been shown to beneficially alter arterial stiffness in selected clinical settings. However, the effects of a standardized exercise protocol – “cardiac rehabilitation (CR)” – on measures of arterial stiffness in patients with established coronary heart disease (CHD) has not been well studied. MethodsUsing applanation tonometry, we studied arterial vascular properties in 26 men and 22 women (mean age 60.5±10.8years) with established CHD over a 20week CR program. All patients continued to receive their anti-anginal and vasoactive medications. In addition to standard hemodynamics we estimated central aortic pressure, central arterial pulsatility, augmentation index and arterial pulse wave velocity (PWV). ResultsAfter 20weeks of CR, there were no significant changes in resting heart rate or peripheral blood pressure. In 33 patients with at least two follow-up visits, central aortic systolic pressure was consistently lower than peripheral arterial blood pressure and decreased over the CR program time (baseline, 109±16mmHg; final, 105±14mmHg. p=0.01). Both carotid–radial (n=12) and carotid–femoral (n=21) — derived PWV decreased over the CR program (carotid–radial: baseline, 7.3±1.2m/s; final, 6.6±1.2m/s, p=0.028. carotid–femoral: baseline, 7.2±1.4m/s; final, 6.5±1.3m/s, p=0.02). ConclusionsIn this group of patients with established CHD, arterial PWV was noted to significantly decrease over a 20week CR program. This change occurred in the absence of detectable changes in peripheral blood pressure or heart rate. Decreases in PWV may serve as a sensitive indicator of improved arterial stiffness in patients with atherosclerotic arterial disease notwithstanding ongoing medical therapy.

Maternal hemodynamics at 11–13 weeks' gestation and risk of pre‐eclampsia

Women who develop pre-eclampsia are at increased risk of cardiovascular disease and stroke in the subsequent decades. Individuals with cardiovascular disorders have increased central aortic systolic blood pressure (SBP(Ao) ) and arterial stiffness, as assessed by pulse wave velocity (PWV) and augmentation index (AIx). The aim of this study was to examine the potential value of assessment of SBP(Ao) , PWV and AIx at 11-13 weeks' gestation in identifying women who subsequently develop pre-eclampsia. This was a screening study for pre-eclampsia in singleton pregnancies at 11 + 0 to 13 + 6 weeks' gestation. Maternal history and characteristics were recorded and PWV, AIx (adjusted to a heart rate of 75 beats per min (AIx-75)) and SBP(Ao) measured. We compared these parameters in women who developed pre-eclampsia (n = 181) with those in unaffected controls (n = 6766) and examined their performance in screening for pre-eclampsia. In the pre-eclampsia group, compared to unaffected controls, there was an increase in AIx-75 (1.13 vs. 1.00 multiples of the median (MoM); P < 0.0001), PWV (1.06 vs. 1.00 MoM; P < 0.0001) and SBP(Ao) (1.09 vs. 1.00 MoM; P < 0.0001). In screening for pre-eclampsia by a combination of maternal variables and log(10) AIx-75 MoM, log(10) PWV MoM and log(10) SBP(Ao) MoM, the estimated detection rate was 56.9% at a false-positive rate of 10%. Compared with women who remain normotensive, women who develop pre-eclampsia have higher SBP(Ao) and arterial stiffness, which is apparent from the first trimester of pregnancy.

Maternal hemodynamics at 11–13 weeks of gestation and preterm birth

Women who experience preterm birth (PTB) are at increased risk of cardiovascular morbidity and mortality in the subsequent decades. Individuals with cardiovascular disorders have increased central aortic systolic blood pressure (SBP(Ao)) and arterial stiffness, assessed by pulse wave velocity (PWV) and augmentation index (AIx). The aim of this screening study was to evaluate SBP(Ao), PWV and AIx at 11-13 weeks' gestation in women who delivered preterm. This was a prospective study in singleton pregnancies at 11 + 0 to 13 + 6 weeks' gestation. Maternal history and characteristics were recorded, and PWV, AIx and SBP(Ao) were measured. We compared these parameters in women who had spontaneous (n = 244) or iatrogenic (n = 110) PTB before 37 weeks' gestation and before 34 weeks with those in women who had term delivery (n = 7489). Compared with women who had term delivery, women who had iatrogenic PTB had significantly higher AIx (1.08 (interquartile range (IQR), 0.91-1.27) multiples of the median (MoM), vs. 1.00 (IQR, 0.86-1.16) MoM) and SBP(Ao) (1.06 (IQR, 0.98-1.15) MoM vs. 1.00 (IQR, 0.93-1.07) MoM). However, there was no significant difference in AIx, PWV or SBP(Ao) between those who had spontaneous PTB and those who had term delivery. These findings were similar for those who had PTB at < 34 and < 37 weeks' gestation. Women who had iatrogenic PTB, but not those who had spontaneous PTB, have increased SBP(Ao) and arterial stiffness that is apparent from as early as the first trimester of pregnancy.

OS084. Maternal haemodynamics at 11–13 weeks of gestation and adverse pregnancy outcomes

Women who develop adverse pregnancy outcomes are at increased risk of cardiovascular disease. In individuals with cardiovascular disorders there is increased central aortic systolic blood pressure (SBPAo) and arterial stiffness. The hypothesis is that increased SBPAo and arterial stiffness are apparent before the clinical onset of adverse pregnancy outcomes. This was a prospective study in singleton pregnancies at 11(+0)-13(+6) weeks' gestation. Pulse wave velocity (PWV), augmentation index (AIx) and SBPAo were measured. At the same visit, we recorded maternal characteristics and medical history and performed combined screening for aneuploidies. We also measured the uterine artery Doppler pulsatility index (PI). The study outcomes included preeclampsia (PE), gestational hypertension (GH), gestational diabetes (GDM), small for gestational age (SGA) and preterm delivery (PTD). The diagnosis of PE and GH was made according to the guidelines of the International Society for the Study of Hypertension in Pregnancy. The neonate was considered SGA if the birth weight was less than the 5th percentile for gestation at delivery. The diagnosis of GDM was made if the fasting plasma glucose level was at least 6 mmol/L or the plasma glucose level 2 h after oral administration of 75 g glucose was 7.8 mmol/L or more (WHO). We compared these parameters in those that developed PE (n=181), GDM (n=105), GH (n=137), SGA (n=337), PTD prior to 37 weeks' gestation (n=354) with unaffected controls (n=6,766). Multiple regression analysis was used to examine which maternal characteristics provided a significant contribution in the prediction of AIx-75, PWV and SBPAo. Each value was expressed as a multiple of the median (MoM) after adjustment for those characteristics. Pearson correlation analysis was used to examine the association between log10AIx-75 MoM, log10PWV MoM, log10 SBPAo MoM, log10uterine artery PI MoM and log10PAPP-A MoM with gestational age at delivery. In the PE group there was an increase in AIx-75 (1.13, IQR 0.96-1.33 MoM vs 1.00, IQR 0.87-1.16 MoM, p<0.0001), PWV (1.11, IQR 0.97-1.17 MoM vs 1.00, IQR 0.90-1.12 MoM, p<0.0001), and SBPAo (1.09, IQR 1.02-1.20 MoM vs. 1.00, IQR 0.94-1.08 MoM, p<0.0001). In those that subsequently developed GH, compared to unaffected controls, there was no significant difference in the uterine artery PI, PAPP-A or PWV but AIx-75 and SBPAo were increased (p<0.0001). In the GDM group there was an increase in PWV (1.06, IQR 0.96-1.19 MoM vs. 1.00, IQR 0.90-1.13 MoM, p=0.001) and SBPAo (1.03, IQR 0.98-1.14 vs. 1.00, IQR 0.94-1.08, p<0.0001), but no significant difference in the AIx-75 (1.02, IQR 0.89-1.22 MoM vs. 1.00, IQR 0.87-1.17 MoM, p=0.118). Compared to women who had term delivery, women who had iatrogenic PTD had significantly higher AIx-75 (1.08, IQR 0.91-1.27 MoM vs. 1.00, IQR 0.86-1.16 MoM, p<0.001) and SBPAo (1.06 MoM, IQR 0.98-1.15 vs. 1.00, IQR 0.93-1.07, p<0.001). A high proportion of women who develop PE, GDM or iatrogenic PTD have increased SBPAo and arterial stiffness that is apparent from the first trimester of pregnancy.