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Accurate measurement of central blood pressure (BP) using upper arm cuff-based methods is associated with several factors, including determining the level of systolic BP (SBP) amplification. This study aimed to determine the agreement between cuff-based and invasively measured SBP amplification. Patients undergoing coronary angiography had invasive SBP amplification (brachial SBP – central SBP) measured simultaneously with cuff-based SBP amplification using a commercially available central BP device (device 1: Sphygmocor Xcel; n = 171, 70% men, 60 ± 10 years) and a now superseded model of a central BP device (device 2: Uscom BP+; n = 52, 83% men, 62 ± 10 years). Mean difference (±2SD, limits of agreement) between cuff-based and invasive SBP amplification was 4 mmHg (−12, +20 mmHg, P < 0.001) for device 1 and −2 mmHg (−14, +10 mmHg, P = 0.10) for device 2. Both devices systematically overestimated SBP amplification at lower levels and underestimated at higher levels of invasive SBP amplification, but with stronger bias for device 1 (r = −0.68 vs. r = −0.52; Z = 2.72; P = 0.008). Concordance of cuff-based and invasive SBP amplification across quartiles of invasive SBP amplification was low, particularly in the lowest and highest quartiles. The root mean square errors from regression between cuff-based central SBP and brachial SBP were significantly lower (indicating less variability) than from invasive regression models (P < 0.001). Irrespective of the difference from invasive measurements, cuff-based estimates of SBP amplification showed evidence of proportional systematic bias and had less individual variability. These observations could provide insights on how to improve the performance of cuff-based central BP.

We propose that for correct clinical interpretation of exaggerated exercise blood pressure (EEBP), both cardiorespiratory fitness and exercise workload must be considered. A key recommendation towards achieving the correct clinical interpretation of EEBP is that exercise BP should be measured during submaximal exercise with a fixed external workload.

The present paper provides an update of previous recommendations on Home Blood Pressure Monitoring from the European Society of Hypertension (ESH) Working Group on Blood Pressure Monitoring and Cardiovascular Variability sequentially published in years 2000, 2008 and 2010. This update has taken into account new evidence in this field, including a recent statement by the American Heart association, as well as technological developments, which have occurred over the past 20 years. The present document has been developed by the same ESH Working Group with inputs from an international team of experts, and has been endorsed by the ESH. ispartof: JOURNAL OF HYPERTENSION vol:39 issue:9 pages:1742-1767 ispartof: location:Netherlands status: published

INTRODUCTION Derivation of blood flow velocity from a blood pressure waveform is a novel technique, which could have potential clinical importance. Excess pressure, calculated from the blood pressure waveform via the reservoir-excess pressure model, is purported to be an analogue of blood flow velocity but this has never been examined in detail, which was the aim of this study. METHODS Intra-arterial blood pressure was measured sequentially at the brachial and radial arteries via fluid-filled catheter simultaneously with blood flow velocity waveforms recorded via Doppler ultrasound on the contralateral arm (n = 98, aged 61 ± 10 years, 72% men). Excess pressure was derived from intra-arterial blood pressure waveforms using pressure-only reservoir-excess pressure analysis. RESULTS Brachial and radial blood flow velocity waveform morphology were closely approximated by excess pressure derived from their respective sites of measurement (median cross-correlation coefficient r = 0.96 and r = 0.95 for brachial and radial comparisons, respectively). In frequency analyses, coherence between blood flow velocity and excess pressure was similar for brachial and radial artery comparisons (brachial and radial median coherence = 0.93 and 0.92, respectively). Brachial and radial blood flow velocity pulse heights were correlated with their respective excess pressure pulse heights (r = 0.53, P

Numerous devices purport to measure central (aortic) blood pressure (BP) as distinct from conventional brachial BP. This validation study aimed to determine the accuracy of the Sphygmocor Xcel cuff device (AtCor Medical, CardieX, Sydney, Australia) for measuring central BP. 296 patients (mean age 61±12 years) undergoing coronary angiography had simultaneous measurement of invasive central BP and noninvasive cuff-derived central BP using the Xcel cuff device (total n=558 individual comparisons). A subsample (n=151) also had invasive brachial BP measured. Methods were undertaken according to the Artery Society recommendations, and several calibration techniques to derive central systolic BP (SBP) were examined. Minimum acceptable error was ≤5±≤8 mm Hg. Central SBP was significantly underestimated, and with wide variability, when using the default calibration of brachial-cuff SBP and diastolic BP (DBP; mean difference±SD, −7.7±11.0 mm Hg). Similar variability was observed using other calibration methods (cuff 33% form-factor mean arterial pressure and DBP, −4.4±11.5 mm Hg; cuff 40% form-factor mean arterial pressure and DBP, 4.7±11.9 mm Hg; cuff oscillometric mean arterial pressure and DBP, −18.2±12.1 mm Hg). Only calibration with invasive central integrated mean arterial pressure and DBP was within minimal acceptable error (3.3±7.5 mm Hg). The difference between brachial-cuff SBP and invasive central SBP was 3.3±10.7 mm Hg. A subsample analysis to determine the accuracy of central-to-brachial SBP amplification showed this to be overestimated by the Xcel cuff device (mean difference 4.3±9.1 mm Hg, P =0.02). Irrespective of cuff calibration technique, the Sphygmocor Xcel cuff device does not meet the Artery Society accuracy criteria for noninvasive measurement of central BP.

Objective: Impaired baroreflex function is an early indicator of cardiovascular autonomic imbalance. Patients with type 2 diabetes mellitus (T2D) have decreased baroreflex sensitivity (BRS), however, whether the neural and/or mechanical component of the BRS (nBRS and mBRS, respectively) is altered in those with high metabolic risk (HMR, impaired fasting glucose and/or metabolic syndrome) or with overt T2D, is unknown. We examined this in a community-based observational study, the Paris Prospective Study III (PPS3). Approach and Results: In 7626 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and RR intervals [time intervals between successive R waves]) and mBRS were measured by high-precision carotid echotracking. The associations between overt T2D or HMR as compared with subjects with normal glucose metabolism (NGM) and nBRS or mBRS were quantified using multivariable linear regression analysis. There were 319 subjects with T2D (61±6 years, 77% male), 1450 subjects with HMR (60±6 years, 72% male), and 5857 subjects with NGM (59±6 years, 57% male). Compared with NGM subjects, nBRS was significantly lower in HMR subjects (β=−0.07 [95% CI, −0.12 to −0.01]; P =0.029) and in subjects with T2D (β=−0.18 [95% CI, −0.29 to −0.07]; P =0.002) after adjustment for confounding and mediating factors. Subgroup analysis suggests significant and independent alteration in mBRS only among HMR patients who had both impaired fasting glucose and metabolic syndrome. Conclusions: In this community-based study of individuals aged 50 to 75, a graded decrease in nBRS was observed in HMR subjects and patients with overt T2D as compared with NGM subjects.

High blood pressure (BP) is a highly prevalent modifiable cause of cardiovascular disease, stroke, and death. Accurate BP measurement is critical, given that a 5-mmHg measurement error may lead to incorrect hypertension status classification in 84 million individuals worldwide. This position statement summarizes procedures for optimizing observer performance in clinic BP measurement, with special attention given to low-to-middle-income settings, where resource limitations, heavy workloads, time constraints, and lack of electrical power make measurement more challenging. Many measurement errors can be minimized by appropriate patient preparation and standardized techniques. Validated semi-automated/automated upper arm cuff devices should be used instead of auscultation to simplify measurement and prevent observer error. Task sharing, creating a dedicated measurement workstation, and using semi-automated or solar-charged devices may help. Ensuring observer training, and periodic re-training, is critical. Low-cost, easily accessible certification programs should be considered to facilitate best BP measurement practice.

Radial intra-arterial blood pressure (BP) is sometimes used as the reference standard for validation of brachial cuff BP devices. Moreover, there is an emerging wearables market seeking to measure BP at the wrist. However, radial systolic BP may differ when compared with brachial; yet some authors have labeled these differences as a fictional Popeye phenomenon. Indeed, differences between brachial and radial systolic BP have never been accurately quantified, and this was the aim of this study. Intra-arterial BP was measured consecutively at the brachial and radial artery in 180 participants undergoing coronary angiography (aged 61±10 years; 69% men). On average, radial systolic BP was 5.5 mm Hg higher than brachial systolic BP. Only 43% of participants had radial systolic BP within ±5 mm Hg of brachial. Additionally, 46%, 19%, and 13% of participants had radial systolic BP >5, between 5 and 10, and between 10 and 15 mm Hg higher than brachial respectively. A further 14% of participants had radial systolic BP >15 mm Hg higher than brachial, representing the so-called Popeye phenomenon. Finally, 11% of participants had radial systolic BP >5 mm Hg lower than brachial. In conclusion, radial systolic BP is not representative of brachial systolic BP, with most participants having a radial systolic BP >5 mm Hg higher than brachial and many with differences >15 mm Hg. Therefore, validation testing of BP devices utilizing intra-arterial BP as the reference standard should use intra-arterial BP measured at the same site as the brachial cuff or wearable device.

Objective:Estimation of aortic blood pressure (BP) requires peripheral BP waveform calibration. Mean arterial pressure (MAP)/DBP calibration is purported to estimate aortic BP more accurately than SBP/DBP calibration. However, this is based on inaccurate cuff calibration. Thus, direct comparisons of

Aims:To estimate the size of regression to the mean with ambulatory blood pressure (ABP) measurement.Methods:Participants from five studies who had repeated blood pressure (BP) measurements using office and ambulatory devices were included. Regression to the mean was calculated following participant

BACKGROUND There is increasing evidence that the method of calibration directly influences the association between brachial systolic blood pressure (bSBP) and estimated aortic systolic blood pressure (aSBP) and subsequently affects prognostic and diagnostic differentiation power of the latter. OBJECTIVE The aim of this study was to investigate associations between different methods of systolic pressure assessment in a large cohort and its comparison with recently published evidence. PARTICIPANTS AND METHODS During a public health campaign, cardiovascular hemodynamic data were assessed using a validated oscillometric device in a pharmacy setting. The device measures bSBP, mean arterial pressure, and diastolic blood pressure (DBP), and records brachial waveforms at the DBP level. aSBP1 was derived using bSBP and DBP and aSBP2 using measured mean arterial pressure and DBP for waveform calibration. In addition to pressures, age, sex, and anthropometric data were recorded. Regression analysis was carried out to investigate associations. RESULTS A total of 7409 (5133/2276, female/male) individuals with a median age of 54 years were sampled. aSBPs differed significantly from bSBP (126.0 mmHg) for aSBP1 (117.0 mmHg) and aSBP2 (127.5 mmHg, both P

BACKGROUND Arterial reservoir characteristics are related to blood pressure (BP) and independently predict cardiovascular events. It is unknown if arterial reservoir characteristics are modified from the central-to-peripheral large arteries and whether there is a contributory role to BP amplification. The aim of this study was to assess central-to-peripheral changes in arterial reservoir characteristics and determine associations with BP. METHODS Reservoir pressure (RP) and excess pressure (XSP) were derived from intra-arterial BP waveforms among 51 participants (aged 63 ± 13 years, 63% men) undergoing clinically indicated cardiac angiography. BP waveforms were recorded in the ascending aorta, brachial (mid-humerus) and radial (wrist) arteries via catheter pull-back. RESULTS There was no significant difference in RP between arterial sites (54 ± 15, 53 ± 15 and 52 ± 17 mmHg for the aorta, brachial and radial artery, respectively; P = 0.68). Conversely, XSP increased stepwise from the aorta to the brachial and radial arteries (24 ± 11, 42 ± 14 and 53 ± 16 mmHg; P

OBJECTIVES Based on anecdotal belief that blood pressure (BP) drops over consecutive measurements, guidelines recommend discarding the first BP reading (Canadian Hypertension Education Program guidelines) or take only one reading if SBP less than 140 mmHg (National Institute for Health and Care Excellence). However, the extent to which SBP fluctuations affect BP classification as well as the potential effect of age are unknown. We sought to assess the change in SBP classification over consecutive measurements following different guidelines, among younger (

Background Reservoir‐wave approach is an alternative model of arterial hemodynamics based on the assumption that measured arterial pressure is composed of volume‐related (reservoir pressure) and wave‐related components (excess pressure). However, the clinical utility of reservoir‐wave approach remains debatable. Methods and Results In a single‐center cohort of 260 dialysis patients, we examined whether carotid and radial reservoir‐wave parameters were associated with all‐cause and cardiovascular mortality. Central pulse pressure and augmentation index at 75 beats per minute were determined by radial arterial tonometry through generalized transfer function. Carotid and radial reservoir‐wave analysis were performed to determine reservoir pressure and excess pressure integral. After a median follow‐up of 32 months, 171 (66%) deaths and 88 (34%) cardiovascular deaths occurred. In Cox regression analysis, carotid excess pressure integral was associated with a hazard ratio of 1.33 (95% CI , 1.14–1.54; P CI : 1.18–1.75; P CI : 1.08–1.54; P =0.004) and cardiovascular mortality (hazard ratio per 1 SD, 1.31; 95% CI : 1.04–1.63; P =0.019). Conversely, there were no significant associations between radial reservoir‐wave parameters, central pulse pressure, augmentation index at 75 beats per minute, pressure forward, pressure backward and reflection magnitude, and all‐cause or cardiovascular mortality after adjustment for comorbidities. Conclusions These observations support the clinical value of reservoir‐wave approach parameters of large central elastic vessels in end‐stage renal disease.

Objective: Decreased aortic reservoir function leads to a rise in aortic reservoir pressure that is an independent predictor of cardiovascular events. Although there is evidence that high-intensity interval training (HIIT) would be useful to improve aortic reservoir pressure, the optimal dose of high-intensity exercise to improve aortic reservoir function has yet to be investigated. Therefore, this study compared the effect of different volumes of HIIT and moderate-intensity continuous training (MICT) on aortic reservoir pressure in participants with the metabolic syndrome (MetS). Methods: Fifty individuals with MetS were randomized into one of the following 16-week training programs: MICT [n¼ 17, 30 min at 60–70% peak heart rate (HRpeak), five times/week]; 4 4-min high-intensity interval training (4HIIT) (n¼ 15, 4 4 min bouts at 85–95% HRpeak, interspersed with 3 min of active recovery at 50–70% HRpeak, three times/week); and 1 4-min high-intensity interval training (1HIIT) (n¼ 18, 1 4 min bout at 85–95% HRpeak, three times/week). Aortic reservoir pressure was calculated from radial applanation tonometry. Results: Although not statistically significant, there was a trend for a small-to-medium group time interaction effect on aortic reservoir pressure, indicating a positive adaptation following 1HIIT compared with 4HIIT and MICT [F (2,46) ¼ 2.9, P ¼ 0.07, h2¼ 0.06]. This is supported by our within-group analysis wherein only 1HIIT significantly decreased aortic reservoir pressure from pre to postintervention (pre–post: 1HIIT 33 16 to 31 13, P ¼ 0.03; MICT 29 9–28 8, P ¼ 0.78; 4HIIT 28 10– 30 9 mmHg, P ¼ 0.10). Conclusion: Three sessions of 4 min of high-intensity exercise per week (12 min/week) was sufficient to improve aortic reservoir pressure, and thus may be a time-efficient exercise modality for reducing cardiovascular risk in individuals with MetS.

Purpose Fit individuals with metabolic syndrome (MetS) have lower mortality risk compared with less fit counterparts, despite the presence of obesity as a component of the syndrome. To understand the importance of fitness in treating this condition, we examined the association of fitness and fatness with central hemodynamic indices that are known independent predictors of cardiovascular events. Methods Sixty-eight individuals with MetS participated in this cross-sectional study. Central hemodynamics is calculated from radial applanation tonometry and comprised aortic reservoir pressure, backward pressure wave (Pb), reflection magnitude (RM), and augmentation index at 75 bpm (AIx75). Cardiorespiratory fitness (CRF) and body fat percentage (BF%) were determined via indirect calorimetry during maximal exercise testing and dual-energy x-ray absorptiometry, respectively. Results CRF was inversely associated with aortic reservoir pressure (r = -0.29, P = 0.02), Pb (r = -0.42, P < 0.001), RM (r = -0.48, P < 0.001), and AIx75 (r = -0.65, P < 0.001). BF% was also correlated with AIx75 (r = 0.37, P < 0.05) and RM (r = 0.36, P < 0.005) but at a weaker association compared with CRF. Multiple regression analysis revealed CRF as a predictor of aortic reservoir pressure (β = -0.52, P =

A reversed aortic-to-brachial stiffness gradient (ab-SG), defined as aortic pulse wave velocity (aPWV) greater than brachial PWV (bPWV), was recently shown to predict mortality independent of aPWV in dialysis patients. Patients with type 2 diabetes mellitus (T2DM) have increased risk of renal damage and exhibit haemodynamic abnormalities at rest and during exercise that may alter the ab-SG. This study aimed to examine ab-SG in patients with T2DM by comparison with nondiabetic controls during rest and exercise, and to determine associations between ab-SG, aPWV, and kidney function.Study participants were 60 patients with T2DM and 60 age and sex-matched nondiabetic controls (58 ± 8 years, 55% male both). ab-SG was defined as the quotient of bPWV (carotid-to-radial) and aPWV (carotid-to-femoral) recorded via applanation tonometry. Kidney function was assessed using estimated glomerular filtration rate (eGFR). The exercise substudy was undertaken in 21 patients with T2DM and 21 matched nondiabetic controls during semirecumbent exercise.ab-SG was significantly lower in patients with T2DM (0.99 ± 0.2 vs. 1.2 ± 0.3, P 0.001) and aPWV, but not bPWV, was significantly higher (P 0.001 and P = 0.25). A total of 58% of patients with T2DM vs. 27% of nondiabetic controls (χ = 11.0, P 0.001) had a reversed ab-SG (aPWV ≥ bPWV). ab-SG predicted eGFR independent of age, sex, T2DM status, and cardiovascular risk factors (β = 13.2, P = 0.024), whereas aPWV did not (β = -0.88, P = 0.30). Exercise ab-SG was significantly lower in patients with T2DM (0.97 ± 0.2 vs. 1.2 ± 0.2, P 0.001), but did not predict eGFR.Patients with T2DM have a reversed ab-SG during rest and exercise. Resting ab-SG predicts kidney function independent of aPWV, implying a reversed ab-SG may have a pathophysiological function.

Reference EPFL-ARTICLE-227670doi:10.1097/Hjh.0000000000001247Afficher la publication dans Web of Science Notice creee le 2017-05-01, modifiee le 2017-05-07

Background: Vascular aging, i.e. accumulation of functional and structural changes of vessels throughout life, is a major contributor to cardiovascular disease. It can be quantified by higher carotid stiffness, intima-media thickness and diameter, and hypertension. Weight gain across the lifetime may be an important, modifiable determinant of vascular aging. Aim: To assess lifetime body silhouette trajectories (a marker of weight change across the lifespan) in relation to vascular aging in late adulthood. Methods: We used cross-sectional data from a community-based study (n=8,083; age 59.4; 38.6% women). A linear mixed model was used to assess trajectories of recalled body silhouettes from age 8 to 45. We assessed carotid stiffness, IMT and diameter (ultrasonography), resting hypertension (blood pressure ≥140/90 mmHg or use of antihypertensives), and exaggerated exercise blood pressure, a marker of masked hypertension (systolic blood pressure ≥150 mmHg during submaximal exercise). Results: We identified 5 trajectories: lean-stable (32%), lean-increase (11%), moderate-stable (33%), lean-marked increase (16%) and heavy-stable (8%). Compared to those in the lean-stable trajectory, individuals in the moderate-stable, lean-marked increase and heavy-stable trajectories had more evidence of vascular aging (Figure). Conclusions: Vascular aging was most prominent among individuals who were lean in early life but gained weight during young adulthood, and among those who were heavy in early life and maintained weight. This suggests that prevention of weight gain across the life course, especially during young adulthood, is important to promote healthy vascular aging.

Background: Physical activity (PA) is beneficial for baroreflex sensitivity (BRS), but it is unclear whether the type of PA has similar effects on the neural (nBRS) or vascular (carotid stiffness) components of BRS. We sought to determine this in healthy adults from a community- based study via assessment of occupational (OPA), sport (SPA), leisure (LPA) and total PA (TPA). Methods: In 8649 adults aged 50 to 75 years, resting nBRS (estimated by low frequency gain, from carotid distension rate and heart rate) and carotid stiffness were measured by high-precision carotid echotracking. PA was self-reported using the Baecke questionnaire, which distinguishes OPA, SPA, LPA and TPA. The associations between PA and nBRS and carotid stiffness were quantified using multivariate linear regression analysis. Analyses were conducted separately in the working and non- working population. Results: In working adults (n=5039), OPA was associated with lower nBRS function (p=0.026) and borderline higher carotid stiffness (p=0.08). The associations between OPA and nBRS remained independent after additionally adjusting for SPA (p=0.03) and exaggerated exercise blood pressure (p=0.005), a predictor of future hypertension and cardiovascular events. When examining the type of OPA separately (i.e. lifting heavy loads, standing or walking at work) lifting heavy loads only was associated with impaired nBRS (p=0.048). When stratified by education, this association remained only in those with less than tertiary education. SPA was associated with higher nBRS (p=0.0005) and borderline lower carotid stiffness (p=0.052). Neither LPA nor TPA was associated with nBRS or carotid stiffness. In non-working adults (n=3610), SPA and TPA were both associated with lower carotid stiffness (p=0.012 and p=0.020), but not nBRS. LPA was not associated with either parameter. Conclusion: Occupation-related PA, in particular lifting heavy loads, is associated with lower nBRS function, especially in those with lower education. Higher amounts of sport-related PA are associated with higher nBRS and lower carotid stiffness.

OBJECTIVES: The reference standard for noninvasive estimation of central blood pressure (BP) is radial tonometry calibrated using brachial SBP and DBP. Brachial-to-radial-SBP amplification (B-R-SBPAmp) may introduce error into central BP estimation, but the magnitude of such amplification is uncertain. This study aimed to determine the magnitude and effect of ageing on B-R-SBPAmp; the effect of B-R-SBPAmp on radial tonometry estimated central SBP; and correlates of B-R-SBPAmp. METHODS: Forty young (28 ± 5 years) and 20 older (60 ± 8 years) healthy participants underwent brachial and radial artery ultrasound to identify SBP from the first Doppler flow inflection during BP cuff deflation (first Korotkoff sound). Impedance cardiography, ultrasound, tonometry and anthropometric data were collected to explore B-R-SBPAmp correlates. RESULTS: Radial SBP was significantly higher than brachial SBP in younger (118 ± 12 versus 110 ± 10 mmHg; P

Measurement of blood pressure (BP) by a doctor in the clinic has limitations that may result in an unrepresentative measure of underlying BP which can impact on the appropriate assessment and management of high BP. Home BP monitoring is the self-measurement of BP in the home setting (usually in the morning and evening) over a defined period (e.g. 7 days) under the direction of a healthcare provider. When it may not be feasible to measure 24-h ambulatory BP, home BP may be offered as a method to diagnose and manage patients with high BP. Home BP has good reproducibility, is well tolerated, is relatively inexpensive and is superior to clinic BP for prognosis of cardiovascular morbidity and mortality. Home BP can be used in combination with clinic BP to identify ‘white coat’ and ‘masked’ hypertension. An average home BP of at least 135/85 mmHg is an appropriate threshold for the diagnosis of hypertension. Home BP may also offer the advantage of empowering patients with their BP management, with benefits including increased adherence to therapy and lower achieved BP levels. It is recommended that, when feasible, home BP should be considered for routine use in the clinical management of hypertension.

The presence of left atrial (LA) dysfunction is linked to the development of both heart failure and atrial fibrillation (AF). Hypertensive heart disease is an important contributor to both LA dysfunction and AF, and hypertension is present in between 50% and 90% of patients in AF trials.1 In the early phases of hypertension, LA conduit function is impaired, and there is compensation by increased booster function.2 Although the association of LA dysfunction with heart failure may be mediated through left ventricular (LV) systolic and diastolic dysfunction,3 the eventual loss of booster function because of AF is an important precipitant of heart failure. Consequently, it seems logical that controlling hypertension and its LV consequences may be a factor in the prevention of AF. Specifically, because LA dysfunction, wall stretch, and enlargement are a consequence of disturbances of LV hemodynamics, a better understanding of the LV systolic–diastolic coupling may have an important role in protecting the LA. See Article by Chirinos et al The historical approach to LV wall stress was that it reflected systolic pressure, wall thickness, and ventricular dimensions.4 However, this was a simplification of the contributors to wall stress, including failure to account for ventricular shape,5 tissue properties, and especially the time course of systolic pressure. Exposure of the LV to late systolic load has effects on LV shape, which in turn may be an important interactive link between LV systole and diastole. A recent literature has linked the timing of wall stress to diastolic dysfunction in both community6 and hypertension-based populations.7 The implication is that it is inaccurate to calculate systolic wall stress at a single time point. …

Objective— Aortic reservoir pressure indices independently predict cardiovascular events and mortality. Despite this, there has never been a study in humans to determine whether the theoretical principles of the mathematically derived aortic reservoir pressure (RP derived ) and excess pressure (XP derived ) model have a real physiological basis. This study aimed to directly measure the aortic reservoir (AR direct ; by cyclic change in aortic volume) and determine its relationship with RP derived , XP derived , and aortic blood pressure (BP). Approach and Results— Ascending aortic BP and Doppler flow velocity were recorded via intra-arterial wire in 10 men (aged 62±12 years) during coronary artery bypass surgery. Simultaneous ascending aortic transesophageal echocardiography was used to measure AR direct . Published mathematical formulae were used to determine RP derived and XP derived . AR direct was strongly and linearly related to RP derived during systole ( r =0.988; P r =0.985; P r =0.98) occurred at a phase lag of 0.004 s into the cardiac cycle, suggesting close temporal agreement between waveforms. The relationship between aortic BP and AR direct was qualitatively similar to the cyclic relationship between aortic BP and RP derived , with peak cross-correlations occurring at identical phase lags (AR direct versus aortic BP, r =0.96 at 0.06 s; RP derived versus aortic BP, r =0.98 at 0.06 s). Conclusions— RP derived is highly correlated with changes in proximal aortic volume, consistent with its physiological interpretation as corresponding to the instantaneous volume of blood stored in the aorta. Thus, aortic reservoir pressure should be considered in the interpretation of the central BP waveform.

BACKGROUND: Lowering blood pressure after stroke reduces the risk of recurrent stroke and other vascular events. However, there is recent evidence that low blood pressure may also result in poor outcome. For the first time, this study aimed to investigate the relationship between blood pressure and outcome in long-term survivors of stroke. METHODS: Participants from the North East Melbourne Stroke Incidence Study were contacted at 5 years after stroke for a follow-up assessment. Blood pressure was measured according to a strict protocol. A multivariable Cox proportional hazards regression model was used to assess the association between SBP measurements at 5 years after stroke and outcome (death, acute myocardial infarction or recurrent stroke) to 10 years after stroke. RESULTS: In 5-year survivors of stroke, compared to a SBP of 131-141 mmHg, a SBP of 120 mmHg or less was associated with a 61% greater risk of stroke, acute myocardial infarction and death (hazard ratio 1.61, 95% confidence interval 1.08-2.41, P = 0.019). Compared to the reference category of SBP 131-141 mmHg, there were no differences in outcome in the patients with SBP 121-130 mmHg (P = 0.491) or 142-210 mmHg (P = 0.313). These findings were not modified when adjusting for prescription of antihypertensive medications. CONCLUSION: There was a greater risk of poor outcome in long-term survivors of stroke with low SBP. This is further evidence that low SBP may result in poor prognosis. Ideal blood pressure levels for long-term survivors of stroke may need to be reassessed.

Objective: Central systolic blood pressure (cSBP) differs from peripheral SBP (pSBP) and may have higher prognostic relevance, but the normal values in ambulatory conditions are unknown. We present reference values for 24-hour central BP profiles, obtained in apparently healthy adult individuals from 20 centers in 14 countries and 5 continents, and compare the findings with peripheral BP. Design and method: 24-hour ambulatory BP monitoring, using a validated oscillometric device (Mobilograph, I.E.M, Stolberg, Germany), was performed in 2527 individuals (1206 men, 1321 women). Central pressures were assessed, using brachial waveforms, calibrated with mean/diastolic BP, and a transfer function. Participants were divided into 6 age groups (18–29, 30–39, 40–49, 50–59, 60–69, 70–99 years). Nighttime/daytime difference (N/D) was defined as nighttime (01.00 - 06.00) minus daytime (09.00 - 21.00) values / daytime values. Results: Averaged 24-hour central BP across all individuals was 128/79 mm Hg (daytime 128/81 mm Hg, nighttime 125/72 mm Hg), with slightly higher BP in men, compared to women. In contrast, central pulse pressure (PP; mean value 48 mm Hg, daytime 46 mm Hg, nighttime 52 mm Hg) was higher in women, compared to men. Mean values for cSBP, diastolic BP, and heart rate were highest in middle age, whereas mean values for cPP were highest in old age. Peripheral SBP N/D was −11% in the youngest age group, and decreased with increasing age, reaching −6% in the oldest age group. In contrast, cSBP N/D was less pronounced, even inverse (1 %) in the youngest age group, reaching −2 % in the oldest age group. Peripheral PP N/D was negligible across all age groups, and central PP N/D was inverse and highest (31 %) in the youngest age group. Conclusions: We provide reference values for apparently healthy individuals across the adult life span for central SBP and PP, comprising 24-hour mean BPs and 24-hour variability. Both differ from peripheral BP. These data may serve for comparison in various diseases and have potential implications for refining hypertension diagnosis and management

Objective:Accurate assessment of mean arterial pressure (MAP) is crucial in clinical and research settings. Measurement of MAP requires pressure waveform integration, but for convenience the standard approach is via form-factor (FF) equations incorporating systolic blood pressure (SBP) measured at a

Objective:Arteriovenous fistula (AVF) is the vascular access of choice in patients with end-stage kidney disease (ESKD) requiring hemodialysis (HD). AVF adds a high flow and low resistance circuit into the arterial system. We had previously shown that AVF is associated with a reduction in blood pres

Arm cuff blood pressure (BP) may overestimate cardiovascular risk. Central aortic BP predicts mortality and could be a better method for patient management. We sought to determine the usefulness of central BP to guide hypertension management. This was a prospective, open-label, blinded–end point study in 286 patients with hypertension randomized to treatment decisions guided by best-practice usual care (n=142; using office, home, and 24-hour ambulatory BP) or, in addition, by central BP intervention (n=144; using SphygmoCor). Therapy was reviewed every 3 months for 12 months, and recommendations were provided to each patient and his/her doctor on antihypertensive medication titration. Outcome measures were as follows: medication quantity (daily defined dose), quality of life, and left ventricular mass (3-dimensional echocardiography). There was 92% compliance with recommendations on medication titration, and quality of life improved in both groups (post hoc P P >0.10), but with intervention there was a significant stepwise decrease in daily defined dose from baseline to 3 months ( P =0.008) and each subsequent visit (all P P P >0.05). We conclude that guidance of hypertension management with central BP results in a significantly different therapeutic pathway than conventional cuff BP, with less use of medication to achieve BP control and no adverse effects on left ventricular mass, aortic stiffness, or quality of life.

Exercise hypertension independently predicts cardiovascular mortality, although little is known about exercise central hemodynamics. This study aimed to determine the contribution of arterial wave travel and aortic reservoir characteristics to central blood pressure (BP) during exercise. We hypothesized that exercise central BP would be principally related to forward wave travel and aortic reservoir function. After routine diagnostic coronary angiography, invasive pressure and flow velocity were recorded in the ascending aorta via sensor-tipped intra-arterial wires in 10 participants (age, 55±10 years; 70% men) free of coronary artery disease with normal left ventricular function. Measures were recorded at baseline and during supine cycle ergometry. Using wave intensity analysis, dominant wave types throughout the cardiac cycle were identified (forward and backward, compression, and decompression), and aortic reservoir and excess pressure were calculated. Central systolic BP increased significantly with exercise (Δ=19±12 mm Hg; P 6 ±17×10 6 W·m −2 ·s −1 ; P =0.045) and forward decompression waves in late systole (Δ=9×10 6 ±6×10 6 W·m −2 ·s −1 ; P P =0.002), reflected waves did not increase in magnitude (Δ=−1×10 6 ±3×10 6 W·m −2 ·s −1 ; P =0.2). Excess pressure rose significantly with exercise (Δ=16±9 mm Hg; P 5 ±5×10 5 Pa·s; P =0.010). Change in reflection coefficient negatively correlated with change in central systolic BP ( r =−0.68; P =0.03). We conclude that elevation of exercise central BP is principally because of increases in aortic forward traveling waves generated by left ventricular ejection. These findings have relevance to understanding central BP waveform morphology and pathophysiology of exercise hypertension.

SACRE, J. W., D. J. HOLLAND, C. JENKINS, and J. E. SHARMAN. Augmentation Index Immediately after Maximal Exercise in Patients with Type 2 Diabetes Mellitus. Med. Sci. Sports Exerc., Vol. 44, No. 1, pp. 75-83, 2012. Introduction: Patients with type 2 diabetes mellitus (T2DM) have exaggerated brachial and central (ascending aortic) blood pressure (BP) during exercise, which is associated with adverse outcomes. Central systolic loading, represented by the augmentation index (AIx), may contribute to exaggerated exercise central BP. This study sought to compare the central AIx response to peak exercise in T2DM and control patients and to identify mechanisms of altered exercise central AIx. Methods: Central BP and AIx were quantified by radial tonometry at rest and immediately after peak treadmill exercise in 106 patients with T2DM and 106 nondiabetic controls, pair-matched by age, gender, peak exercise brachial BP, and postexercise HR corresponding to tonometry acquisition. Cardiac volumes (by echocardiography) were assessed in a subgroup (22 T2DM and 22 controls) to derive rest and postexercise arterial-ventricular coupling parameters, including cardiac index (stroke volume index x HR), peripheral vascular resistance index (cardiac index / mean BP), and effective arterial elastance index (end-systolic pressure / stroke volume index). Reserve parameters (exercise - rest) were also defined. Results: Patients with T2DM had lower postexercise central AIx (-1% +/- 13% vs 3% +/- 14%, P = 0.038) and greater central AIx reserve (-24% +/- 13% vs -20% +/- 11%, P = 0.002) compared with controls, despite raised postexercise peripheral vascular resistance index (P = 0.013) and effective arterial elastance index (P = 0.011); these parameters independently predicted higher central AIx at rest (P < 0.01) but not after exercise. Moreover, T2DM was independently associated with lower postexercise central AIx (A = -0.21, P = 0.006). Cardiac index reserve, which was blunted in T2DM (P = 0.004), represented the only independent correlate of central AIx reserve (r = 0.39, P = 0.01). Conclusions: Patients with T2DM have significantly (and paradoxically) lower postexercise central AIx and greater central AIx reserve, which may be explained by an impaired cardiac functional reserve.

Background Hypertension is ubiquitous in patients with heart failure and preserved ejection fraction (HFpEF) and contributes to arterial and ventricular stiffening. Exertional dyspnea may result from diastolic dysfunction with exercise; however, the association of central bloodpressure (BP) to left ventricular filling pressure during exercise has not been assessed in this population and was the aim of this study. Methods Fifteen patients with HFpEF and 15 age-matched and sex-matched controls were studied at rest, during submaximal and immediately after maximal exercise. Simultaneous echocardiography and radial tonometry was performed to measure E/e’ and central BP, defined by central augmented pressure (C_AP) and augmentation index (AIx). Results Patients with HFpEF had higher E/e’ (PU0.020) and peripheral and central BP (P0.05). There was a large increase in E/e’ with exercise in patients (PU0.012) but no change in C_AP or AIx. Importantly, the change in E/e’ from rest to submaximal exercise was significantly and independently associated with DC_AP (rU0.559; PU0.030) and DAIx (rU0.654; PU0.008) in patients with HFpEF. In contrast with the controls, E/e’, C_AP and AIx decreased with exercise and there were no associations between exercise E/e’ and central or peripheral BP (P>0.05 for all). Conclusion Indices of central BP are associated with the left ventricular diastolic response to exercise in patients with HFpEF. Arterial function and central hemodynamics may be important targets for treating symptoms associated with raised left ventricular filling pressure with exertion.