Evaluation of 24-Hour Arterial Stiffness Indices and Central Hemodynamics in Healthy Normotensive Subjects versus Treated or Untreated Hypertensive Patients: A Feasibility Study

Association of 24-h central hemodynamics and stiffness with cardiovascular events and all-cause mortality. The VASOTENS Registry

OBJECTIVES

In hemodialysis patients, central hemodynamics, stiffness, and wave reflections assessed through ambulatory blood pressure monitoring (ABPM) showed superior prognostic value for cardiovascular (CV) events than peripheral blood pressures (BPs). No such evidence is available for lower-risk hypertensive patients.

METHODS

In 591 hypertensive patients (mean age 58 ± 14 years, 49% males), ambulatory brachial and central BP, pulse wave velocity (PWV), and augmentation index (AIx) were obtained with a validated upper arm cuff-based pulse wave analysis technology. Information on treatment for hypertension (73% of patients), dyslipidemia (27%), diabetes (8%), CV disease history (25%), was collected. Patients were censored for CV events or all-cause death over 4.2 years.

RESULTS

One hundred and four events (24 fatal) were recorded. Advanced age [hazard ratio and 95% confidence interval: 1.03 (1.01, 1.05), P  = 0.0001], female sex [1.57 (1.05, 2.33), P  = 0.027], CV disease [2.22 (1.50, 3.29), P  = 0.0001], increased 24-h central pulse pressure (PP) [1.56 (1.05, 2.31), P  = 0.027], PWV [1.59 (1.07, 2.36), P  = 0.022], or AIx [1.59 (1.08, 2.36), P  = 0.020] were significantly associated with a worse prognosis (univariate Cox regression analysis). The prognostic power of peripheral and central BPs was lower. However, PWV [1.02 (0.64, 1.63), P  = 0.924], AIx [1.06 (0.66, 1.69), P  = 0.823], and central PP [1.18 (0.76, 1.82), P  = 0.471], were not significant predictors in multivariate analyses.

CONCLUSIONS

In hypertensive patients, ambulatory central PP, PWV, and AIx are associated with an increased risk of CV morbidity and all-cause mortality. However, this association is not independent of other patient characteristics.

Feasibility of Arteriograph 24 for evaluation of 24-hour pulse wave velocity and central blood pressure in patients with type 2 diabetes and non-diabetic controls

The objective of this study was to assess the feasibility of the Arteriograph 24 device to measure 24-hour PWV and central systolic blood pressure (cSBP) in patients with type 2 diabetes (T2DM) and non-diabetic controls and compare daytime and nighttime characteristics in the two groups. Twenty-four-hour PWV and cSBP was measured in 58 patients with T2DM (mean age: 66 ± 9 years, 50% women, mean duration of T2DM: 7.8 ± 1.5 years) and 62 age- and sex-matched controls. Seventy percent of participants (71% T2DM patients and 69% controls) had sufficient readings to generate an acceptable 24-hour report (≥14 day and ≥7 night readings). Lower nocturnal than daytime PWV and cSBP were observed in both groups. Nocturnal PWV and cSBP dipping were attenuated in T2DM patients compared to controls (PWV: -0.3 ± 0.9 vs. -0.7 ± 0.9 m/s, P  = 0.04, cSBP: -8 ± 14 vs. -18 ± 18 mmHg, P  < 0.01). No group differences in PWV or cSBP were observed during daytime (T2D vs. controls, PWV: 9.2 ± 1.1 vs. 9.2 ± 1.3 m/s, P  = 0.99, cSBP: 133 ± 19 vs. 137 ± 25 mmHg, P  = 0.42) or nighttime (PWV: 8.9 ± 1.3 vs. 8.4 ± 1.3 m/s, P  = 0.14, cSBP 124 ± 20 vs. 118 ± 27 mmHg, P  = 0.26). The study findings indicate that the nocturnal dipping of PWV and cSBP is attenuated in T2DM patients. The significant number of missing measurements raises concerns regarding the clinical utility of the Arteriograph 24 device.

Arterial stiffness and its influence on cerebral morphology and cognitive function

Background

Recently, arterial stiffness has been associated with cerebral small vessel disease (SVD), brain atrophy and vascular dementia. Arterial stiffness is assessed via pulse wave velocity (PWV) measurement and is strongly dependent on arterial blood pressure. While circadian blood pressure fluctuations are important determinants of end-organ damage, the role of 24-h PWV variability is yet unclear.

Objectives

We here investigated the association between PWV and its circadian changes on brain morphology and cognitive function in community-dwelling individuals.

Design

Single-centre, prospective, community-based follow-up study.

Methods

The study cohort comprised elderly community-based participants of the Austrian Stroke Prevention Family Study which was started in 2006. Patients with any history of cerebrovascular disease or dementia were excluded. The study consists of 84 participants who underwent ambulatory 24-h PWV measurement. White matter hyperintensity volume and brain volume were evaluated by 3-Tesla magnetic resonance imaging (MRI). A subgroup of patients was evaluated for cognitive function using an extensive neuropsychological test battery.

Results

PWV was significantly related to reduced total brain volume (p = 0.013), which was independent of blood pressure and blood pressure variability. We found no association between PWV with markers of cerebral SVD or impaired cognitive functioning. Only night-time PWV values were associated with global brain atrophy (p = 0.005).

Conclusions

This study shows a relationship of arterial stiffness and reduced total brain volume. Elevations in PWV during night-time are of greater importance than day-time measures.

Characterization of Vascular Patterns Associated with Endothelial Glycocalyx Damage in Early- and Late-Onset Preeclampsia

This paper provides an assessment of molecular and functional changes in blood vessels, and a description of vascular patterns during preeclampsia (PE). Patients with normal pregnancy, and pregnancy complicated by PE at earlier (20-34 weeks) and later terms (≥34 weeks) underwent a 24 h monitoring of blood pressure, central hemodynamics, arterial stiffness, and myocardial function. The blood levels of the structural components of endothelial glycocalyx (eGC): syndecan-1 (SDC 1), heparan sulfate proteoglycan 2 (HSPG2), and hyaluronic acid (HA) were determined. In early-onset PE, the vascular pattern comprised changes in all structural components of eGCs, including transmembrane proteoglycans levels, and severe disorders of central hemodynamics, arterial stiffness, and myocardial changes, probably leading to more severe course of PE and the formation of morphological grounds for cardiovascular disorders. The vascular pattern in late-onset PE, including changes in HA levels, central hemodynamics, and myocardial function, may be a signal of potential cardiovascular disorder. PE may change adaptive hemodynamic responses to a pathological reaction affecting both arterial elasticity and the left ventricular myocardium, with its subsequent hypertrophy and decompensation, leading to a delayed development of cardiovascular disorders after PE. Further clinical studies of these indicators will possibly identify predictors of PE and long-term consequences of the disease.

Impact of hypertension phenotypes on the office and 24-h pulse wave velocity and augmentation index in individuals with or without antihypertensive medication use

Data on the association of blood pressure (BP) phenotypes with office and out-of-office markers of vascular stiffness and pressure wave reflection are sparse. This study investigated office and 24-h measures of brachial BP, pulse wave velocity (PWV), and central augmentation index (AIx) across hypertension phenotypes among individuals not using BP-lowering medications [normotension (NT), white-coat hypertension (WH), masked hypertension (MH) and sustained hypertension (SH)] and those using BP-lowering medications [controlled hypertension (CH), white-coat uncontrolled hypertension (WUCH), masked uncontrolled hypertension (MUCH) and sustained uncontrolled hypertension (SUCH)]. We evaluated 454 untreated (age = 45 ± 15 years, 50% males) and 238 treated (age = 52 ± 15 years, 45% males) individuals who underwent office and 24-h brachial BP, PWV, and AIx measures using a Mobil-O-Graph PWA monitor. In the analysis adjusted for age and sex, WH had higher (p < 0.05) office PWV (7.53 ± 0.09 vs 6.89 ± 0.05), office AIx (27.9 ± 1.3 vs 23.8 ± 0.8), and daytime AIx (24.6 ± 0.7 vs 22.7 ± 0.4) compared with those of NT, while WUCH had higher (p < 0.05) office PWV (8.28 ± 0.11 vs 7.43 ± 0.08) and 24-h PWV (7.54 ± 0.09 vs 7.21 ± 0.07) than those of CH. MH had higher (p < 0.05) 24-h PWV (7.00 ± 0.09 vs 6.69 ± 0.04) and 24-h AIx (24.3 ± 0.9 vs 21.9 ± 0.4) than those of NT, whereas MUCH had higher (p < 0.05) 24-h PWV (7.64 ± 0.13 vs 7.21 ± 0.07) than that of CH. Lastly, SH or SUCH had significantly higher office and 24-h PWV and AIx than those of NT and CH, respectively. In conclusion, these results suggest that individuals with masked BP phenotypes are more predisposed to have adverse out-of-office vascular characteristics, while individuals with white-coat phenotypes have adverse office and out-of-office vascular characteristics compared with those of individuals with normal BP levels.

Chronic Kidney Disease and Pulse Wave Velocity: A Narrative Review

Chronic kidney disease (CKD) is associated with excess cardiovascular mortality, resulting from both traditional and nontraditional, CKD-specific, cardiovascular risk factors. Nontraditional risk factors include the entity Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) which is characterised by disorders of bone and mineral metabolism, including biochemical abnormalities of hyperphosphatemia and hyperparathyroidism, renal osteodystrophy, and vascular calcification. Increased arterial stiffness in the CKD population can be attributed amongst other influences to progression of vascular calcification, with significant resultant contribution to the cardiovascular disease burden. Pulse wave velocity (PWV) measured over the carotid-femoral arterial segments is the noninvasive gold-standard technique for measurement of aortic stiffness and has been suggested as a surrogate cardiovascular end-point. A PWV value of 10 m/s or greater has been recommended as a suitable cut-off for an increased risk of cardiovascular mortality. CKD is a risk factor for an excessive rate of increase in aortic stiffness, reflected by increases in PWV, and increased aortic PWV in CKD shows faster progression than for individuals with normal kidney function. Patients with varying stages of CKD, as well as those on dialysis or with a kidney transplant, have different biological milieu which influence aortic stiffness and associated changes in PWV. This review discusses the pathophysiology of arterial stiffness with CKD and outlines the literature on PWV across the spectrum of CKD, highlighting that determination of arterial stiffness using aortic PWV can be a useful diagnostic and prognostic tool for assessing cardiovascular disease in the CKD population.

Ambulatory pulse wave monitoring: current and future. Opinion paper of Russian Experts

The predictive value of vascular biomarkers such as pulse wave velocity (PWV), central arterial pressure (CAP), and augmentation index (AIx), obtained through pulse wave analysis (PWA) in resting conditions, has been documented in a variety of patient groups and populations. There are appropriate recommendations on their clinical use in clinical practice guidelines of various scientific societies. Operator-independent methods are currently available for estimating vascular biomarkers also in ambulatory conditions. The acceptable accuracy and reproducibility of ambulatory PWA makes it be a promising tool for evaluating vascular biomarkers in daily-life conditions. This approach may provide an opportunity to further improve the early cardiovascular screening in subjects at risk. However, there is no sufficient evidence to support the routine clinical use of PWA in ambulatory conditions at the moment. In particular, long-term outcome studies are needed to show the predictive value of ambulatory PWV, CAP and AIx values.

Daily variability of arterial stiffness of patients with arterial hypertension depending on the category of cardiovascular risk

PURPOSE

The study of the daily variability of arterial stiffness indicators, depending on the category of cardiovascular risk. Materials and methods. The study consistently included patients with essential hypertension who were admitted to the cardiology department of the Volga district medical center from November 1, 2015 to October 1, 2017. The study involved 134 patients with an average age of 52±1 years. Depending on the category of total cardiovascular risk, the patients were divided into 3 groups from I (lowest risk) to III (highest risk). The analysis was carried out on ABPM for 12-14 days (BPLab system of "Peter Telegin" firm). Determined: glomerular filtration rate (GFR), the thickness of the intima-media of the common carotid arteries, analysis of the lipid spectrum. For statistical analysis of clinical and instrumental data, a T-criterion for independent samples was used and an ANOVA analysis was performed. A correlation analysis was performed. Results. Patients of group III had the highest level of av. SBP (рI-III =0.010; pII-III =0.020) and mean pulse BP (PBP) (рI-III =0.002; pII-III =0.002), also more unfavorable the indicators cALALx (pI-II=0.025; рI-III =0.004), varAlx (рI-III =0.004) and av. ASI (рI-III =0.034). When comparing the data of patients of groups II and III, adjusted for gender and age, it was found that statistically significant differences between the groups of varPAD (pII-III =0.008), AASI (рI-III =0.043), varAlx (pII-III=0.049), as well as a pronounced tendency for varASI (pII-III=0.050). Markers of target organ damage (TIM, LVML, GFR) were more pronounced in the high-risk group. As the risk group increased, the level of HDL decreased (рI-III =0.002; pII-III I=0.0001), the level of TG increased (рI-III =0.007; pII-III =0.009) and the CA (рI-III =0.015). The total cholesterol level was lower in patients of group III compared to group II (pII-III=0.004). Statistically signifi nt relationships of arterial wall stiffness indicators with age were found: crAlx (0.467, p&lt;0.001), varAlx (0.272, p&lt;0.01), cpASI (0.227, p&lt;0.01), varASI (0.407, p&lt;0.001). In addition, women showed significant correlations of medium and high strength between age and mean values of mean SPD (r = 0.490, p&lt;0.05), varPAD (r=0.540, p&lt;0.05), avAS (r=0.460, p&lt;0.05) and varASI (r=0.620, p&lt;0.05). VarASI and WedSASI were most closely associated with the level of SRSAD and SRPAD. Only cASI was associated with GFR, and only varASI was associated with the parameters of the lipid spectrum (HSLPVP, TG, KA and LVMI. Conclusion. The most statistically significant dynamics was observed when evaluating varASI, which varied in the sequence I gr. &lt;II gr. &lt; III gr. Corrected by sex and age, the analysis showed a greater variability in arterial stiffness in high-risk patients.

Twenty-Four-Hour Ambulatory Pulse Wave Analysis in Hypertension Management: Current Evidence and Perspectives

The predictive value of vascular biomarkers such as pulse wave velocity (PWV), central arterial pressure (CAP), and augmentation index (AIx), obtained through pulse wave analysis (PWA) in resting conditions, has been documented in a variety of patient groups and populations. This allowed to make appropriate recommendations in clinical practice guidelines of several scientific societies. Due to advances in technologies, largely operator-independent methods are currently available for estimating vascular biomarkers also in ambulatory conditions, over the 24 h. According to the acceptable accuracy and reproducibility of 24-h ambulatory PWA, it appears to be a promising tool for evaluating vascular biomarkers in daily life conditions. This approach may provide an opportunity to further improve the early cardiovascular screening in subjects at risk. However, concerning the clinical use of PWA over the 24 h in ambulatory conditions at the moment, there is no sufficient evidence to support its routine clinical use. In particular, long-term outcome studies are needed to show the predictive value of 24-h PWV, CAP, and AIx values, provided by these devices, over and beyond peripheral blood pressure, and to answer the many technical and clinical questions still open. To this regard, the VASOTENS Registry, an international observational prospective study recently started, will help providing answers on a large sample of hypertensive patients recruited worldwide.

Relationships between 24-h blood pressure variability and 24-h central arterial pressure, pulse wave velocity and augmentation index in hypertensive patients

Twenty-four-h blood pressure variability (BPV) predicts cardiovascular complications in hypertension, but its association with pulse wave indices (central arterial pressure, pulse wave velocity (PWV) and augmentation index (AIx)) is poorly understood. In the present study, we assessed the degree of the effect of 24-h BPV on 24-h pulse wave indices. Brachial blood pressure was measured non-invasively over the 24 h with an electronic, oscillometric, automated device (BPLab) in 661 uncomplicated treated or untreated hypertensive patients. Digitalized oscillometric waveforms were analyzed with a validated algorithm to obtain pulse wave indices. Twenty-four-h BPV was calculated as the unweighted (SDu) or weighted s.d. (SDw) of the mean blood pressure or as the average real variability (ARV). Twenty-four-h systolic BPV showed a direct and significant relationship with the central arterial systolic pressure (r=0.28 SDu, r=0.40 SDw, r=0.34 ARV), PWV (r=0.10 SDu, r=0.21 SDw, r=0.19 ARV) and AIx (r=0.17 SDu, r=0.27 SDw, r=0.23 ARV). After adjustment for age, sex, body mass index, antihypertensive treatment and 24-h systolic blood pressure, the relationship lost some power but was still significant for all measures, except for the AIx. Pulse wave indices were higher in patients with high BPV than in those with low BPV: after adjustment, these differences were abolished for the AIx. The diastolic BPV showed a weak association with the pulse wave indices. In conclusion, in hypertensive patients, 24-h systolic BPV is moderately and independently associated with 24-h central arterial pressure and stiffness.

Arterial stiffness in obstructive sleep apnoea: Is there a difference between daytime and night-time?

BACKGROUND AND OBJECTIVE

Obstructive sleep apnoea syndrome (OSAS) is a common chronic systemic disease in the general population, with known associated cardiovascular outcomes. We aimed to investigate arterial stiffness in OSAS patients and compare daytime and night-time values with control subjects.

METHODS

A total of 104 patients undergoing investigation for OSAS with polysomnography also underwent pulse wave velocity (PWV) and augmentation index (AIx) measurements with Mobil-O-Graph for 24 h. Eighty-two patients were found to have OSAS and 22 did not have OSAS and acted as controls.

RESULTS

PWV values of the 82 OSAS patients during the 24-h period, both daytime and night-time, were significantly higher than that of the control subjects. Moreover, night-time levels of AIx were significantly higher in OSAS patients than control subjects (P = 0.025). PWV during night-time was higher than daytime measurements in OSAS patients (P = 0.012). Apnoea hypopnoea index (AHI) was significantly correlated with PWV and AIx over 24 h (P = 0.0001, r = 0.412; P = 0.002, r = 0.333, respectively). Positive correlations were also found between oxygen desaturation index (ODI) with PWV and AIx during the night (P = 0.0001, r = 0.480; P = 0.002, r = 0.325, respectively). However, daytime AIx was not significantly correlated with ODI (P = 0.052, r = 0.205).

CONCLUSION

OSAS patients, without known cardiovascular disease, have increased PWV, indicating an increased arterial stiffness, compared with control subjects and correlations between AHI and arterial stiffness indices suggest increased arterial stiffness with increased disease severity. Therefore, arterial stiffness should be considered as a possible cause for cardiovascular complications in OSAS patients.

Vascular Health Assessment of The Hypertensive Patients (VASOTENS) Registry: Study Protocol of an International, Web-Based Telemonitoring Registry for Ambulatory Blood Pressure and Arterial Stiffness

Background

Hypertension guidelines recommend ambulatory blood pressure (ABP), central aortic pressure (CAP), and pulse wave velocity (PWV) as parameters for estimating blood pressure (BP) control and vascular impairment. Recent advances in technology have enabled devices to combine non-invasive estimation of these parameters over the 24-hour ABP monitoring. However, currently there is limited evidence on the usefulness of such an approach for routine hypertension management.

Objective

We recently launched an investigator-initiated, international, multicenter, observational, prospective study, the Vascular health Assessment Of The Hypertensive patients (VASOTENS) Registry, aimed at (1) evaluating non-invasive 24-hour ABP and arterial stiffness estimates (through 24-hour pulse wave analysis, PWA) in hypertensive subjects undergoing ambulatory blood pressure monitoring (ABPM) for clinical reasons; (2) assessing the changes in estimates following treatment; (3) weighing the impact of 24-hour PWA on target organ damage and cardiovascular prognosis; (4) assessing the relationship between arterial stiffness, BP absolute mean level and variability, and prognosis; and (5) validating the use of a 24-hour PWA electronic health (e-health) solution for hypertension screening.

Methods

Approximately 2000 subjects, referred to 20 hypertension clinics for routine diagnostic evaluation and follow-up of hypertension of any severity or stage, will be recruited. Data collection will include ABPM, performed with a device allowing simultaneous non-invasive assessment of 24-hour CAP and arterial stiffness (BPLab), and clinical data (including cardiovascular outcomes). As recommended by current guidelines, each patient will be followed-up with visits occurring at regular intervals (ideally every 6 months, and not less than once a year depending on disease severity). A Web-based telemedicine platform (THOLOMEUS) will be used for data collection. The use of the telemedicine system will allow standardized and centralized data collection, data validation by experts and counseling to remote centers, setup and maintenance of the Registry, and prompt data analysis.

Results

First follow-up results are expected to be available in the next 2 years.

Conclusions

The results of the VASOTENS Registry will help define the normalcy thresholds for current and future indices derived from 24-hour PWA, according to outcome data, and will also provide supporting evidence for the inclusion of this type of evaluation in hypertension management.

Trial registration

Clinicaltrials.gov NCT02577835; https://clinicaltrials.gov/ct2/show/NCT02577835 (Archived by WebCite at http://www.Webcitation.org/6hzZBKY2Q)

Arterial stiffness and coronary artery disease

PURPOSE OF REVIEW

The current traditional risk scores are not sufficient to predict the full incidence of cardiovascular disease. In this brief review, we discuss the pathophysiological mechanisms through which arterial stiffness affects cardiac function and the additive value of markers of arterial stiffness, to detect the presence of coronary artery disease (CAD) and predict adverse outcome in these patients.

RECENT FINDINGS

Arterial stiffness causes early arrival of wave reflections in systole instead of diastole and, thus, increases systolic afterload and reduces diastolic coronary perfusion pressure. Abnormal collagen turnover, cytokines, and metalloproteinase activity are common biochemical links between vascular and myocardial stiffness. Pulse wave velocity, augmentation index, and central pressures measured by simple noninvasive methods are related to atheromatic plaque vulnerability, incidence, severity, and extent of CAD. Recent meta-analyses have shown the additive value of markers of arterial stiffness, and particularly of pulse wave velocity, to detect CAD, predict cardiovascular events, and reclassify patients to a higher cardiovascular risk. Studies assessing whether reduction of arterial stiffness is associated with improved prognosis are lacking.

SUMMARY

Markers of arterial stiffness are useful tools to identify early atherosclerosis and adverse clinical outcomes in young adults and individuals with a modest risk factor profile. Assessing arterial stiffness may facilitate cardiovascular risk stratification beyond traditional risk scores.

Comparison of the BPLab® sphygmomanometer for ambulatory blood pressure monitoring with mercury sphygmomanometry in pregnant women: validation study according to the British Hypertension Society protocol

The purpose of this study was to validate the automated BPLab® sphygmomanometer for ambulatory blood pressure monitoring (ABPM) in pregnant women according to Part II of the 1993 British Hypertension Society protocol. Pregnant women attending the antenatal clinic were randomly asked to participate (n=30). The BPLab sphygmomanometer was tested on pregnant women in this study and achieved A/A ratings according to the BHS protocol when compared with the "gold" standard of mercury sphygmomanometry. The device can therefore be recommended for use in pregnancy.