Central blood pressure: current evidence and clinical importance

The Impact of a Plant-Based Diet on Indices of Cardiovascular Health in African Americans: A Cross-Sectional Study

African American (AA) individuals are disproportionately affected by cardiovascular diseases. Plant-based diets (PBD) may be cardioprotective in part through their high antioxidant capacity and low inflammatory load. We tested the hypothesis that AA individuals adhering to a 100% PBD would have better vascular health than AA individuals following a typical American diet (TAD). Eighteen AA individuals participated; 9 (24±4 years; 6 females) were following a PBD for 2.4±0.8 years and 9 (21±2 years; 5 females) were following a TAD. Blood lipids and C-reactive protein (CRP) were assessed. Peripheral and central blood pressure (BP) were measured, and vascular function tests included cerebrovascular reactivity to hypercapnia, brachial artery flow-mediated dilation & reactive hyperemia, and local heating-induced cutaneous hyperemia. Total (TC) and low-density lipoprotein (LDL-C) serum cholesterol were lower (TC: 142±30 vs. 174±36 mg/dl; LDL-C: 76±17 vs. 106±33 mg/dl; p<0.05 and d>0.80 for both) and serum CRP tended to be lower (0.38±0.18 mg/l vs. 0.96±0.89 mg/l; p=0.05, d=0.91) in the PBD cohort. Brachial (b) and central (c) mean arterial BP (MAP) were lower in the PBD cohort (bMAP: 86±5 vs. 91±7 mmHg; cMAP: 81±5 vs. 87±7 mmHg; p<0.05 and d>0.80 for both). All indices of vascular function were similar between groups (p>0.05 for all). A PBD was associated with more optimal blood lipid concentrations and decreased peripheral and central BP in AA individuals, but this association was not present in the various indices of vascular function. Registered at ClinicalTrials.gov: NCT05344287.

Combined oxidant capacity, redox-weighted oxidant capacity and elevated blood pressure: A panel study

BACKGROUND

Evidence is limited on the potential health effects of Ox (sum value) and Oxwt(weighted value), the two surrogates for ozone (O3) and nitrogen dioxides (NO2).

OBJECTIVES

To investigate the impacts of Ox and redox-weighted oxidant capacity (Oxwt) on blood pressure (BP).

METHODS

A panel study was conducted with four repeated follow-up visits among 40 healthy college students in Hefei, Anhui Province, China from August to October, 2021. We measured BP by using an automated sphygmomanometer and obtained hourly data of air pollutants at a nearby site. The sum of O3 and NO2 (Ox) and their weighted average (Oxwt) were obtained as exposure variables. We applied linear mixed-effect models to evaluate the effects of Ox and Oxwton systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP).

RESULTS

Totally, 160 pairs of valid BP values were obtained. The 24-h mean levels of Ox and Oxwt were 64.38 μg/m3 and 110.28 μg/m3, respectively. Overall, both Ox and Oxwt were significantly linked with SBP, DBP and MAP at most lag periods, whereas non-significant with PP. A 10-μg/m3 increase in Oxwt at lag 0-24 h was linked to increases of 2.43 mmHg (95% CI: 0.96, 3.91) in SBP, 2.31 mmHg (95% CI: 1.37, 3.26) in DBP and 2.35 mmHg (95% CI: 1.35, 3.36) in MAP, while the corresponding effect estimates for Ox were 1.51 mmHg (95%CI: 0.60, 2.43), 1.43 mmHg (95% CI: 0.85, 2.02) and 1.46 mmHg (95%CI: 0.83, 2.09). In two-pollutant models, our results were almost unchanged after controlling for simultaneous exposure to other pollutants. The effects were more pronounced among males and those with physical activity.

CONCLUSIONS

The findings provide first-hand evidence that short-term exposure to Ox and Oxwt was associated with BP increases in young adults.

New Insights Into Cerebrovascular Pathophysiology and Hypertension

Despite advances in acute management and prevention of cerebrovascular disease, stroke and vascular cognitive impairment together remain the world's leading cause of death and neurological disability. Hypertension and its consequences are associated with over 50% of ischemic and 70% of hemorrhagic strokes but despite good control of blood pressure (BP), there remains a 10% risk of recurrent cerebrovascular events, and there is no proven strategy to prevent vascular cognitive impairment. Hypertension evolves over the lifespan, from predominant sympathetically driven hypertension with elevated mean BP in early and mid-life to a late-life phenotype of increasing systolic and falling diastolic pressures, associated with increased arterial stiffness and aortic pulsatility. This pattern may partially explain both the increasing incidence of stroke in younger adults as well as late-onset, chronic cerebrovascular injury associated with concurrent systolic hypertension and historic mid-life diastolic hypertension. With increasing arterial stiffness and autonomic dysfunction, BP variability increases, independently predicting the risk of ischemic and intracerebral hemorrhage, and is potentially modifiable beyond control of mean BP. However, the interaction between hypertension and control of cerebral blood flow remains poorly understood. Cerebral small vessel disease is associated with increased pulsatility in large cerebral vessels and reduced reactivity to carbon dioxide, both of which are being targeted in early phase clinical trials. Cerebral arterial pulsatility is mainly dependent upon increased transmission of aortic pulsatility via stiff vessels to the brain, while cerebrovascular reactivity reflects endothelial dysfunction. In contrast, although cerebral autoregulation is critical to adapt cerebral tone to BP fluctuations to maintain cerebral blood flow, its role as a modifiable risk factor for cerebrovascular disease is uncertain. New insights into hypertension-associated cerebrovascular pathophysiology may provide key targets to prevent chronic cerebrovascular disease, acute events, and vascular cognitive impairment.

Racial and ethnic disparities in cardiometabolic disease and COVID-19 outcomes in White, Black/African American, and Latinx populations: Physiological underpinnings

Coronavirus disease 2019 (COVID-19) is a highly contagious respiratory illness caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) that began spreading globally in late 2019. While most cases of COVID-19 present with mild to moderate symptoms, COVID-19 was the third leading cause of mortality in the United States in 2020 and 2021. Though COVID-19 affects individuals of all races and ethnicities, non-Hispanic Black and Hispanic/Latinx populations are facing an inequitable burden of COVID-19 characterized by an increased risk for hospitalization and mortality. Importantly, non-Hispanic Black and Hispanic/Latinx adults have also faced a greater risk of non-COVID-19-related mortality (e.g., from cardiovascular disease/CVD) during the pandemic. Contributors to the racial disparities in morbidity and mortality during the pandemic are multi-factorial as we discuss in our companion article on social determinants of health. However, profound racial variation in the prevalence of CVD and metabolic diseases may serve as a key driver of worse COVID-19-related and non-COVID-19-related health outcomes among racial and ethnic minority groups. Within this review, we provide data emphasizing the inequitable burden of CVD and metabolic diseases among non-Hispanic Black and Hispanic/Latinx populations. We also discuss the pathophysiology of these conditions, with a focus on how aberrant physiological alterations in the context of CVD and metabolic diseases manifest to increase susceptibility to severe COVID-19.

Vascular dysfunction and dyslipidemia in multiple sclerosis: are they correlated with disease duration and disability status?

BACKGROUND

There is strong evidence that vascular dysfunction is considered one of the possible causes of morbidity and mortality in patients suffering from multiple sclerosis (MS). This work aimed at assessing the arterial function and serum lipids in MS patients and correlating them with clinical and radiological findings.

RESULTS

This case-control study included 50 patients with MS and 50 age- and sex-matched controls. The arterial function was significantly reduced in MS patients, confirmed by significantly higher pulse wave velocity (PWV) and augmentation index (AIX), while the carotid IMT did not show significant difference between the two groups with no plaques in any of our patients. A significant positive correlation was found between PWV and both disease duration and disability. MS patients had significantly higher serum levels of T-cholesterol and triglycerides, and significantly lower serum levels of HDL-cholesterol, compared to controls. No significant correlation was found between serum lipids and either disease duration or disability.

CONCLUSIONS

There was a significant impairment in arterial function (assessed by the brachial cuff-based method via Mobil-O-Graph device) in MS patients compared to controls. Such impairment was significantly correlated with both disease duration and disability. MS patients had also significantly higher levels of T-cholesterol and triglycerides, compared to controls with no significant correlation between serum lipids and either disease duration or disability.

Simultaneous adaption of the gain and phase of a generalized transfer function for aortic pressure waveform estimation

GOAL

This paper proposes and validates a completely adaptive transfer function (CATF) based on an autoregressive exogenous (ARX) model which adjusts the gain and phase of a generalized transfer function (GTF) simultaneously to estimate the aortic pressure waveform from a brachial pressure waveform.

METHODS

Invasive aortic and brachial pressure waveforms were recorded from 34 subjects for the validation of the proposed method. Individual transfer functions (ITFs) were trained based on the pressure waveforms using an ARX model. The GTF was derived by averaging the ITFs. CATF was then obtained by adjusting both the gain and phase of the GTF using regression formulas calculated from the ITFs and brachial hemodynamic parameters. Meanwhile the quantitative contributions of the adaption of gain and phase of the GTF were investigated respectively. The root-mean-square-error of the total waveform and absolute errors of common hemodynamic indices including systolic and diastolic blood pressures (SBP and DBP, respectively), pulse pressure (PP) and augmentation index were used to evaluate the performance of the proposed method in the data divided into low, middle and high PP amplification groups.

RESULTS

The CATF achieved lower errors for DBP and PP in the low PP amplification group (1.79 versus 2.10 mmHg and 5.08 versus 6.23 mmHg, respectively, both P < 0.05) and PP in the middle amplification group (1.43 versus 1.92 mmHg, P < 0.05) compared with the GTF.

SIGNIFICANCE

The proposed method provides a step towards the development of an improved and clinically useful non-invasive approach for estimating the aortic pressure waveform from a peripheral pressure waveform.

The effect of non-invasively obtained central blood pressure on cardiovascular outcome in diabetic patients in Assiut University Hospitals

Background

The major cause of morbidity and mortality in diabetes is cardiovascular disease, which is exacerbated by the presence of hypertension. Therefore, proper control of BP in diabetic hypertensive patients is essential. Few studies have specifically investigated the prognostic significance of central BP in Egyptian populations with diabetes and hypertension and its relation with cardiovascular outcome. This study aims to evaluate relation between central BP and diabetic composite cardiovascular complications.

Results

Diabetic patients with CVD were significantly older (p value < 0.01), obese (p value < 0.01) with long duration of diabetes (p value < 0.001) and had significantly higher peripheral and central systolic and diastolic BP and higher AIx@75(p values < 0.01) than those without CVD. Regarding the metabolic parameters, they had significantly higher fasting blood glucose, HbA1c, and higher blood cholesterol levels (p values < 0.001), higher LDL (p value < 0.01), triglycerides levels (p value = 0.014), and microalbuminuria (p value = 0.028). Logistic regression analysis found increased BMI, central systolic BP, and AIx@75 were independent predictors of composite CVD (p values < 0.05).

Conclusions

There is a pattern of favorability towards central rather than peripheral BP indices to predict the occurrence of CVD in diabetic patients.

High-frame-rate A-mode ultrasound for calibration-free cuffless carotid pressure: feasibility study using lower body negative pressure intervention

PURPOSE

Existing technologies to measure central blood pressure (CBP) intrinsically depend on peripheral pressure or calibration models derived from it. Pharmacological or physiological interventions yielding different central and peripheral responses compromise the accuracy of such methods. We present a high-frame-rate ultrasound technology for cuffless and calibration-free evaluation of BP from the carotid artery. The system uses a pair of single-element ultrasound transducers to capture the arterial diameter and local pulse wave velocity (PWV) for the evaluation of beat-by-beat BP employing a novel biomechanical model.

MATERIALS AND METHODS

System's functionality assessment was conducted on eight male subjects (26 ± 4 years, normotensive and no history of cardiovascular risks) by perturbing pressure via short-term moderate lower body negative pressure (LBNP) intervention (-40 mmHg for 1 min). The ability of the system to capture dynamic responses of carotid pressure to LBNP was investigated and compared against the responses of peripheral pressure measured using a continuous BP monitor.

RESULTS

While the carotid pressure manifested trends similar to finger measurements during LBNP, the system also captured the differential carotid-to-peripheral pressure response, which corroborates the literature. The carotid diastolic and mean pressures agreed with the finger pressures (limits-of-agreement within ±7 mmHg) and exhibited acceptable uncertainty (mean absolute errors were 2.4 ± 3.5 and 2.6 ± 4.0 mmHg, respectively). Concurrent to the literature, the carotid systolic and pulse pressures (PPs) were significantly lower than those of the finger pressures by 11.1 ± 9.4 and 11.3 ± 8.2 mmHg, respectively (p < .0001).

CONCLUSIONS

The study demonstrated the method's potential for providing cuffless and calibration-free pressure measurements while reliably capturing the physiological aspects, such as PP amplification and dynamic pressure responses to intervention.

The International Database of Central Arterial Properties for Risk Stratification: Research Objectives and Baseline Characteristics of Participants

OBJECTIVE

To address to what extent central hemodynamic measurements, improve risk stratification, and determine outcome-based diagnostic thresholds, we constructed the International Database of Central Arterial Properties for Risk Stratification (IDCARS), allowing a participant-level meta-analysis. The purpose of this article was to describe the characteristics of IDCARS participants and to highlight research perspectives.

METHODS

Longitudinal or cross-sectional cohort studies with central blood pressure measured with the SphygmoCor devices and software were included.

RESULTS

The database included 10,930 subjects (54.8% women; median age 46.0 years) from 13 studies in Europe, Africa, Asia, and South America. The prevalence of office hypertension was 4,446 (40.1%), of which 2,713 (61.0%) were treated, and of diabetes mellitus was 629 (5.8%). The peripheral and central systolic/diastolic blood pressure averaged 129.5/78.7 mm Hg and 118.2/79.7 mm Hg, respectively. Mean aortic pulse wave velocity was 7.3 m per seconds. Among 6,871 participants enrolled in 9 longitudinal studies, the median follow-up was 4.2 years (5th-95th percentile interval, 1.3-12.2 years). During 38,957 person-years of follow-up, 339 participants experienced a composite cardiovascular event and 212 died, 67 of cardiovascular disease.

CONCLUSIONS

IDCARS will provide a unique opportunity to investigate hypotheses on central hemodynamic measurements that could not reliably be studied in individual studies. The results of these analyses might inform guidelines and be of help to clinicians involved in the management of patients with suspected or established hypertension.

The Clinical Impact of β-Blocker Therapy on Patients With Chronic Coronary Artery Disease After Percutaneous Coronary Intervention

The general knowledge that β-blockers are cardioprotective for patients with chronic coronary artery disease (CAD) is mainly extrapolated from positive evidence in patients with myocardial infarction (MI) or heart failure. In this propensity score-matched cohort study of 1,170 pairs of patients with chronic CAD who underwent percutaneous coronary intervention, we analysed medical records for β-blockers with prescription doses and types in each patient at 3-month intervals after discharge. β-blockers were not associated with better clinical outcomes for mortality and MI. Additionally, no significant associations were found for the clinical outcomes with different doses and types of β-blockers.

Background and Objectives

The outcome benefits of β-blockers in chronic coronary artery disease (CAD) have not been fully assessed. We evaluated the prognostic impact of β-blockers on patients with chronic CAD after percutaneous coronary intervention (PCI).

Methods

A total of 3,075 patients with chronic CAD were included from the Grand Drug-Eluting Stent registry. We analyzed β-blocker prescriptions, including doses and types, in each patient at 3-month intervals from discharge. After propensity score matching, 1,170 pairs of patients (β-blockers vs. no β-blockers) were derived. Primary outcome was defined as a composite endpoint of all-cause death and myocardial infarction (MI). We further analyzed the outcome benefits of different doses (low-, medium-, and high-dose) and types (conventional or vasodilating) of β-blockers.

Results

During a median (interquartile range) follow-up of 3.1 (3.0–3.1) years, 134 (5.7%) patients experienced primary outcome. Overall, β-blockers demonstrated no significant benefit in primary outcome (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.63–1.24), all-cause death (HR, 0.87; 95% CI, 0.60–1.25), and MI (HR, 1.25; 95% CI, 0.49–3.15). In subgroup analysis, β-blockers were associated with a lower risk of all-cause death in patients with previous MI and/or revascularization (HR, 0.38; 95% CI, 0.14–0.99) (p for interaction=0.045). No significant associations were found for the clinical outcomes with different doses and types of β-blockers.

Conclusions

Overall, β-blocker therapy was not associated with better clinical outcomes in patients with chronic CAD undergoing PCI. Limited mortality benefit of β-blockers may exist for patients with previous MI and/or revascularization.

Trial Registration

ClinicalTrials.gov Identifier: NCT03507205

24-hour central blood pressure and immune system activation in adolescents with primary hypertension - a preliminary study

Introduction

Adult and pediatric data suggest a positive relationship between the extent of subclinical inflammation, blood pressure, and hypertension-mediated organ damage (HMOD) in primary hypertension (PH). 24-hour (24-h) ambulatory blood pressure (ABPM) and central blood pressure (CBP) are strong predictors of HMOD. Our study aimed to analyze the relationship between 24-h central ABPM, subclinical inflammation, and clinical data in adolescents with PH.

Material and methods

In 28 untreated adolescents with PH (14.50 ±2.27 years) and 25 healthy peers (14.76 ±2.83 years), we analyzed 24-h peripheral and central ABPM, markers of subclinical inflammation (neutrophil-to-lymphocyte ratio - NLR, platelet-to-lymphocyte ratio - PLR, mean platelet volume - MPV), and clinical and biochemical data.

Results

Patients with PH had higher 24-h peripheral and central blood pressure than healthy peers. In all 53 patients, we found significant (p < 0.05) positive correlations between NLR, PLR and 24-h central systolic, diastolic, and mean blood pressure (24-h cSBP, 24-h cDBP, 24-h cMAP), between 24-h central augmentation index corrected for heart rate 75 (24-h cAIx75HR) and platelet count. In 28 patients with PH, 24-h cAIx75HR correlated with low-density lipoprotein (LDL) cholesterol (R = 0.442), and ambulatory arterial stiffness index with body mass index (BMI) (R = 0.487), uric acid (R = 0.430), and high-density lipoprotein (HDL) cholesterol (R = -0.428).

Conclusions

Increased central 24-h blood pressure may be associated with immune system activation in adolescents with primary hypertension. In adolescents with primary hypertension, dyslipidemia and hyperuricemia are risk factors for increased arterial stiffness. Further studies on central and peripheral blood pressure in terms of their relationship with inflammation in these patients are needed.

Central versus ambulatory blood pressure for predicting mortality and cardiovascular events in hemodialysis patients: a multicenter cohort study

OBJECTIVE

Studies in the general population suggest that central blood pressure (BP) may be superior to peripheral BP in risk assessment. Although ambulatory brachial BP is recognized as the most reliable BP measurement in the dialysis population, there is no comparison of office central BP with ambulatory BP regarding risk stratification in these patients.

METHODS

In a multicenter prospective study of dialysis patients, central BP was measured noninvasively on a midweek nondialysis day, with interdialytic ambulatory BP and predialysis BP also collected. The primary outcomes were a composite of major adverse cardiovascular events (MACE) and all-cause mortality. Agreement between central and ambulatory BP was assessed using Cohen's Kappa index and Bland--Altman plot. Linear and nonlinear Cox regression models were used to determine the association of BP parameters with outcomes.

RESULTS

A total of 368 patients were recruited and 366 underwent central BP measurement. Central BP had a moderate agreement with ambulatory BP in defining hypertension (κ = 0.42) with wide limits of agreement in Bland--Altman analysis. After a median follow-up of 51.5 months, central pulse pressure, ambulatory SBP and ambulatory pulse pressure were associated with all-cause mortality, whereas all BP parameters, except for predialysis DBP, were significant predictors of MACE. However, whenever evaluated in a stepwise variable selection Cox model, only ambulatory pulse pressure, but not any central BP, was determined as the best candidate for prediction of both all-cause mortality and MACE. Nonlinear Cox models revealed no significant nonlinear trend of the association between central BP and outcomes.

CONCLUSION

Central BP is predictive of all-cause mortality and cardiovascular events in dialysis patients but its prognostic value does not outperform ambulatory peripheral BP. Our data support the superiority of ambulatory BP in the dialysis population.

Off-Target Effects of Antidepressants on Vascular Function and Structure

Depression emerges as a risk factor for cardiovascular disease, and it is thought that successful antidepressant treatment may reduce such a risk. Therefore, antidepressant treatment embodies a potential preventive measure to reduce cardiovascular events in patients with depression. Accumulating evidence indicates that antidepressants have off-target effects on vascular dysfunction and in the early stages of atherosclerosis, which form the basis for cardiovascular disease (CVD) pathogenesis. In this context, we performed a thorough review of the evidence pertaining to the effects of different classes of antidepressant medications on hemodynamic and early atherosclerosis markers. The preclinical and clinical evidence reviewed revealed a preponderance of studies assessing selective serotonin reuptake inhibitors (SSRI), whereas other classes of antidepressants are less well-studied. Sufficient evidence supports a beneficial effect of SSRIs on vascular inflammation, endothelial function, arterial stiffening, and possibly delaying carotid atherosclerosis. In clinical studies, dissecting the hypothesized direct beneficial antidepressant effect of SSRIs on endothelial health from the global improvement upon remission of depression has proven to be difficult. However, preclinical studies armed with appropriate control groups provide evidence of molecular mechanisms linked to endothelial function that are indeed modulated by antidepressants. This suggests at least a partial direct action on vascular integrity. Further research on endothelial markers should focus on the effect of antidepressants on treatment responders versus non-responders in order to better ascertain the possible beneficial vascular effects of antidepressants, irrespective of the underlying course of depression.

New Method to Estimate Central Systolic Blood Pressure From Peripheral Pressure: A Proof of Concept and Validation Study

Objective: The non-invasive estimation of central systolic blood pressure (cSBP) is increasingly performed using new devices based on various pulse acquisition techniques and mathematical analyses. These devices are most often calibrated assuming that mean (MBP) and diastolic (DBP) BP are essentially unchanged when pressure wave travels from aorta to peripheral artery, an assumption which is evidence-based. We tested a new empirical formula for the direct central blood pressure estimation of cSBP using MBP and DBP only (DCBP = MBP²/DBP).

Methods and Results: First, we performed a post-hoc analysis of our prospective invasive high-fidelity aortic pressure database (n = 139, age 49 ± 12 years, 78% men). The cSBP was 146.0 ± 31.1 mmHg. The error between aortic DCBP and cSBP was −0.9 ± 7.4 mmHg, and there was no bias across the cSBP range (82.5–204.0 mmHg). Second, we analyzed 64 patients from two studies of the literature in whom invasive high-fidelity pressures were simultaneously obtained in the aorta and brachial artery. The weighed mean error between brachial DCBP and cSBP was 1.1 mmHg. Finally, 30 intensive care unit patients equipped with fluid-filled catheter in the radial artery were prospectively studied. The cSBP (115.7 ± 18.2 mmHg) was estimated by carotid tonometry. The error between radial DCBP and cSBP was −0.4 ± 5.8 mmHg, and there was no bias across the range.

Conclusion: Our study shows that cSBP could be reliably estimated from MBP and DBP only, provided BP measurement errors are minimized. DCBP may have implications for assessing cardiovascular risk associated with cSBP on large BP databases, a point that deserves further studies.

Associations between measurements of central blood pressure and target organ damage in high-risk patients

Background

It is not well-known which components of central blood pressure (CBP) are more influential to target organ damage (TOD). This study aimed to determine the relationship between CBP measurements and various types of TOD in high-risk patients.

Methods

A total of 148 patients who had documented atherosclerotic cardiovascular disease or its multiple risk factors were prospectively enrolled. CBP was measured by using applanation tonometry of the radial artery. The following nine TOD parameters were evaluated: left ventricular mass index, relative wall thickness, septal e′ velocity, septal E/e′, brachial-ankle pulse wave velocity, ankle-brachial index, estimated glomerular filtration rate, urine protein and obstructive coronary artery disease.

Results

The mean age of the study population was 67.1 ± 9.0 years and 108 (73 %) were male. Among four CBP measurements (systolic, diastolic, mean, and pulse pressures), central pulse pressure (CPP) was associated with the largest number of TOD parameters. As CPP increased, the number of TOD increased (P = 0.010), but this association was not observed in other CBP measurements (P > 0.05 for each).

Conclusions

CPP had a stronger correlation with TOD than other CBP measurements. Non-invasive CPP could be a useful indicator for predicting TOD in patients at high coronary risk.

Twenty-Four-Hour Central (Aortic) Systolic Blood Pressure: Reference Values and Dipping Patterns in Untreated Individuals

Supplemental Digital Content is available in the text.

Central (aortic) systolic blood pressure (cSBP) is the pressure seen by the heart, the brain, and the kidneys. If properly measured, cSBP is closer associated with hypertension-mediated organ damage and prognosis, as compared with brachial SBP (bSBP). We investigated 24-hour profiles of bSBP and cSBP, measured simultaneously using Mobilograph devices, in 2423 untreated adults (1275 women; age, 18–94 years), free from overt cardiovascular disease, aiming to develop reference values and to analyze daytime-nighttime variability. Central SBP was assessed, using brachial waveforms, calibrated with mean arterial pressure (MAP)/diastolic BP (cSBP_MAP/DBPcal), or bSBP/diastolic blood pressure (cSBP_SBP/DBPcal), and a validated transfer function, resulting in 144 509 valid brachial and 130 804 valid central measurements. Averaged 24-hour, daytime, and nighttime brachial BP across all individuals was 124/79, 126/81, and 116/72 mm Hg, respectively. Averaged 24-hour, daytime, and nighttime values for cSBP_MAP/DBPcal were 128, 128, and 125 mm Hg and 115, 117, and 107 mm Hg for cSBP_SBP/DBPcal, respectively. We pragmatically propose as upper normal limit for 24-hour cSBP_MAP/DBPcal 135 mm Hg and for 24-hour cSBP_SBP/DBPcal 120 mm Hg. bSBP dipping (nighttime-daytime/daytime SBP) was −10.6 % in young participants and decreased with increasing age. Central SBP_SBP/DBPcal dipping was less pronounced (−8.7% in young participants). In contrast, cSBP_MAP/DBPcal dipping was completely absent in the youngest age group and less pronounced in all other participants. These data may serve for comparison in various diseases and have potential implications for refining hypertension diagnosis and management. The different dipping behavior of bSBP versus cSBP requires further investigation.

A SAGE score cutoff that predicts high-pulse wave velocity as measured by oscillometric devices in Brazilian hypertensive patients

We aimed to identify the optimal cutoff SAGE score for Brazilian hypertensive patients who had their pulse wave velocity (PWV) measured with oscillometric devices. A retrospective analysis of patients who underwent central blood pressure measurement using a validated oscillometric device, the Mobil-O-Graph® (IEM, Stolberg, Germany), between 2012 and 2019 was performed. Patients with arterial hypertension and available data on all SAGE parameters were selected. An ROC curve was constructed using the Youden index to define the best score to identify patients at high risk for high PWV. A total of 837 patients met the criteria for SAGE and diagnosis of hypertension. The median age was 59.0 years (interquartile range [IQR]: 47.0-68.0), and 50.7% of the patients were women. The following comorbidities and conditions were present: dyslipidemia (37.4%), diabetes (20.7%), a body mass index score ≥30 kg/m² (36.6%), use of antihypertensive drugs (69.5%), and smoking (18.3%). The median peripheral blood pressure was 128 mmHg (IQR: 117-138 mmHg) for systolic and 81 mmHg (IQR: 73-90 mmHg) for diastolic blood pressure. The median PWV was 8.3 m/s (7.1-9.8 m/s), and the prevalence of high PWV (≥10 m/s) was 22.9% (192 patients). A cutoff SAGE score ≥8 was effective at identifying a high risk of PWV ≥ 10 m/s, achieving 67.19% sensitivity (95% CI: 60.1-73.8) and 93.95% specificity (95% CI: 91.8-95.7). With this cutoff point, 1 out of every 5 treated hypertensive patients would be referred for a PWV measurement. A SAGE score of ≥8 identified Brazilian hypertensive patients with a high risk of future cardiovascular events (PWV ≥ 10 m/s).

Pulsatile Hemodynamics and Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of human death and has a high prevalence throughout the world. Therefore, it is important to detect CAD early and to apply individualized therapy according to the patients' risk. There is an increasing interest in pulsatile arterial hemodynamics in the cardiovascular area. Widely used measurements of arterial pulsatile hemodynamics include pulse pressure, pulse wave velocity and augmentation index. Here, we will review underlying pathophysiology linking the association of arterial pulsatile hemodynamics with CAD, and the usefulness of the measurements of pulsatile hemodynamics in the prediction of future cardiovascular events of CAD patients. Clinical and therapeutic implications will be also addressed.

The effectiveness and safety of isometric resistance training for adults with high blood pressure: a systematic review and meta-analysis

High blood pressure (BP) is a global health challenge. Isometric resistance training (IRT) has demonstrated antihypertensive effects, but safety data are not available, thereby limiting its recommendation for clinical use. We conducted a systematic review of randomized controlled trials comparing IRT to controls in adults with elevated BP (systolic ≥130 mmHg/diastolic ≥85 mmHg). This review provides an update to office BP estimations and is the first to investigate 24-h ambulatory BP, central BP, and safety. Data were analyzed using a random-effects meta-analysis. We assessed the risk of bias with the Cochrane risk of bias tool and the quality of evidence with GRADE. Twenty-four trials were included (n = 1143; age = 56 ± 9 years, 56% female). IRT resulted in clinically meaningful reductions in office systolic (-6.97 mmHg, 95% CI -8.77 to -5.18, p < 0.0001) and office diastolic BP (-3.86 mmHg, 95% CI -5.31 to -2.41, p < 0.0001). Novel findings included reductions in central systolic (-7.48 mmHg, 95% CI -14.89 to -0.07, p = 0.035), central diastolic (-3.75 mmHg, 95% CI -6.38 to -1.12, p = 0.005), and 24-h diastolic (-2.39 mmHg, 95% CI -4.28 to -0.40, p = 0.02) but not 24-h systolic BP (-2.77 mmHg, 95% CI -6.80 to 1.25, p = 0.18). These results are very low/low certainty with high heterogeneity. There was no significant increase in the risk of IRT, risk ratio (1.12, 95% CI 0.47 to 2.68, p = 0.8), or the risk difference (1.02, 95% CI 1.00 to 1.03, p = 0.13). This means that there is one adverse event per 38,444 bouts of IRT. IRT appears safe and may cause clinically relevant reductions in BP (office, central BP, and 24-h diastolic). High-quality trials are required to improve confidence in these findings. PROSPERO (CRD42020201888); OSF ( https://doi.org/10.17605/OSF.IO/H58BZ ).

The importance of calibration method in determining the association between central blood pressure with left ventricular and left atrial strain

Afterload is an important determinant of left ventricular (LV) and atrial (LA) function, including myocardial strain. Central blood pressure (CBP) is the major component of cardiac afterload and independently associated with cardiovascular risk. However, the optimal means of calibrating CBP is unclear-standard CBP assessment uses systolic (SBP) and diastolic blood pressure (DBP) from brachial waveforms, but calibration with mean pressure (MAP) and DBP purports to be more accurate. Therefore, we sought to determine which CBP is best associated with LA and LV strain. CBP was measured using both standard and MAP based calibration methods in 546 participants (age 70.7 ± 4.7 years, 45% male) with risk factors for heart failure. Echocardiography was performed in all patients and strain analysis conducted to assess LA/LV function. The associations of CBP with LA and LV strain were assessed using linear regression. MAP-derived CSBP (150 ± 20 mmHg) was higher than standard CSBP (128 ± 15 mmHg) and brachial SBP (140 ± 17 mmHg, p < 0.001), whereas DBPs were similar (84 ± 10, 83 ± 10, and 82 ± 10 mmHg). MAP-derived CSBP was not independently associated with LV strain (p > 0.05), however was independently associated with LA reservoir strain (p < 0.05). Brachial and central DBP were more strongly associated with LA reservoir/conduit and LV strain than brachial and central SBP. LA pump strain was not independently associated with any SBP or DBP parameter (p > 0.05). MAP-derived CBP was more accurate in identifying patients with abnormal LA and LV strain than brachial SBP and standard CBP calibration. In conclusion, CBP calibrated using MAP and DBP may be more accurate in identifying patients with abnormal LA and LV function than standard brachial calibration methods.

Leveraging the potential of machine learning for assessing vascular ageing: state-of-the-art and future research

Vascular ageing biomarkers have been found to be predictive of cardiovascular risk independently of classical risk factors, yet are not widely used in clinical practice. In this review, we present two basic approaches for using machine learning (ML) to assess vascular age: parameter estimation and risk classification. We then summarize their role in developing new techniques to assess vascular ageing quickly and accurately. We discuss the methods used to validate ML-based markers, the evidence for their clinical utility, and key directions for future research. The review is complemented by case studies of the use of ML in vascular age assessment which can be replicated using freely available data and code.

A Transfer Function Model Development for Reconstructing Radial Pulse Pressure Waveforms Using Non-Invasively Measured Pulses by a Robotic Tonometry System

The primary goal of this study is to develop a mathematical model that can establish a transfer function relationship between the “external” pulse pressures measured by a tonometer and the “internal” pulse pressure in the artery. The purpose of the model is to accurately estimate and rebuild the internal pulse pressure waveforms using arterial tonometry measurements. To develop and validate a model without human subjects and operators for consistency, this study employs a radial pulse generation system, a robotic tonometry system, and a write model with an artificial skin and vessel. A transfer function model is developed using the results of the pulse testing and the mechanical characterization testing of the skin and vessel. To evaluate the model, the pulse waveforms are first reconstructed for various reference pulses using the model with tonometry data. They are then compared with pulse waveforms acquired by internal measurement (by the built-in pressure sensor in the vessel) the external measurement (the on-skin measurement by the robotic tonometry system). The results show that the model-produced pulse waveforms coinciding well with the internal pulse waveforms with small relative errors, indicating the effectiveness of the model in reproducing the actual pulse pressures inside the vessel.

Metabolic Profiling and Metabolites Fingerprints in Human Hypertension: Discovery and Potential

Early detection of pathogenesis through biomarkers holds the key to controlling hypertension and preventing cardiovascular complications. Metabolomics profiling acts as a potent and high throughput tool offering new insights on disease pathogenesis and potential in the early diagnosis of clinical hypertension with a tremendous translational promise. This review summarizes the latest progress of metabolomics and metabolites fingerprints and mainly discusses the current trends in the application in clinical hypertension. We also discussed the associated mechanisms and pathways involved in hypertension's pathogenesis and explored related research challenges and future perspectives. The information will improve our understanding of the development of hypertension and inspire the clinical application of metabolomics in hypertension and its associated cardiovascular complications.

Associations of blood pressure and arterial stiffness with knee cartilage volume in patients with knee osteoarthritis

OBJECTIVE

To describe the associations of blood pressure and arterial stiffness with knee cartilage volume in patients with knee OA.

METHODS

A secondary analysis was performed on the data from participants in a randomized controlled trial that identified the effects of vitamin D supplementation on knee structures and symptoms among patients with symptomatic knee OA. Brachial and central blood pressure, arterial stiffness indicators and knee cartilage volume were measured at baseline and the 2 year follow-up. Associations were assessed using generalized estimating equations.

RESULTS

Among 231 participants (average age 63.2 years), 48.9% were females. Higher supine systolic and diastolic pressures were significantly associated with lower tibial cartilage volume (systolic: lateral β -6.23, medial β -5.14, total β -11.35 mm3/mmHg; diastolic: lateral β -10.25, medial β -11.29, total β -21.50 mm3/mmHg). Higher supine systolic pressure was associated with lower femoral cartilage volume (lateral β -17.35, total β -28.31 mm3/mmHg). Central systolic pressure and arterial stiffness indicators (including pulse wave velocity, central pulse pressure and peripheral pulse pressure) were largely not associated with knee cartilage volume; however, higher augmentation index was associated with lower tibial and femoral cartilage volume (tibial: medial β -8.24, total β -19.13 mm3/%; femoral: lateral β -23.70, medial β -26.42, total β -50.12 mm3/%).

CONCLUSIONS

Blood pressure and arterial stiffness are associated with knee cartilage volume at several sites in knee OA patients. This supports that blood pressure and arterial stiffness may involve in the progression of knee OA.

Central Systolic Blood Pressure Is Associated With Early Vascular Damage in Children and Adolescents With Type 1 Diabetes

Objective of the study: This study aimed to test the effect of multiple cardiovascular risk factors on subclinical indices of atherosclerosis in children and adolescents with type 1 diabetes (T1D).

Methods: Carotid intima-media thickness (cIMT), carotid distensibility coefficient (cDC), and carotid–femoral pulse wave velocity (PWV) were measured in children and adolescents with T1D, in a follow-up at the outpatient clinics of Verona. Blood pressure (BP; both central and peripheral), metabolic and other cardiovascular risk factors were evaluated in multivariate linear regressions to assess the association with the measured indices of subclinical vascular damage.

Results: One hundred and twenty-six children and adolescents were included. cIMT was above the 95th percentile for age and height in 60.8% of the population, whereas 26% of the sample had cDC impairment (less than the 5th percentile) and 4.8% had an elevated PWV. Independent determinants of cIMT according to the regression models were only gender type of glucose monitoring and central systolic BP (cSBP). PWV was associated with age, sex, heart rate, and cSBP; cDC with age and both cSBP and, alternatively, peripheral BP (pBP). Neither pBP nor any of the tested metabolic parameters, including glycated hemoglobin, was associated with PWV and cIMT.

Conclusions: A high proportion of early vascular damage, especially an increased cIMT, is present in children and adolescents with T1D in whom cSBP seems to be a common determinant. In children and adolescents with T1DM, a special focus should be on hemodynamic risk factors beyond metabolic ones.

Establishment of a Modular Hemodynamic Simulator for Accurate In Vitro Simulation of Physiological and Pathological Pressure Waveforms in Native and Bioartificial Blood Vessels

Purpose

In vitro stimulation of native and bioartificial vessels in perfusable systems simulating natural mechanical environments of the human vasculature represents an emerging approach in cardiovascular research. Promising results have been achieved for applications in both regenerative medicine and etiopathogenetic investigations. However, accurate and reliable simulation of the wide variety of physiological and pathological pressure environments observed in different vessels still remains an unmet challenge.

Methods

We established a modular hemodynamic simulator (MHS) with interchangeable and modifiable components suitable for the perfusion of native porcine—(i.e. the aorta, brachial and radial arteries and the inferior vena cava) and bioartificial fibrin-based vessels with anatomical site specific pressure curves. Additionally, different pathological pressure waveforms associated with cardiovascular diseases including hyper- and hypotension, tachy- and bradycardia, aortic valve stenosis and insufficiency, heart failure, obstructive cardiomyopathy and arterial stiffening were simulated. Pressure curves, cyclic distension and shear stress were measured for each vessel and compared to ideal clinical pressure waveforms.

Results

The pressure waveforms obtained in the MHS showed high similarity to the ideal anatomical site specific pressure curves of different vessel types. Moreover, the system facilitated accurate emulation of physiological and different pathological pressure conditions in small diameter fibrin-based vessels.

Conclusion

The MHS serves as a variable in vitro platform for accurate emulation of physiological and pathological pressure environments in biological probes. Potential applications of the system include bioartificial vessel maturation in cardiovascular tissue engineering approaches as well as etiopathogenetic investigations of various cardiovascular pathologies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13239-021-00577-0.

The effect of continuous positive airway pressure on blood pressure in patients with obstructive sleep apnea and uncontrolled hypertension - Study design and challenges during the COVID-19 pandemic

OBJECTIVES

To describe the MORPHEOS (Morbidity in patients with uncontrolled HTN and OSA) trial, and describe the challenges imposed by the COVID-19 pandemic.

METHODS

MORPHEOS is a multicenter (n=6) randomized controlled trial designed to evaluate the blood pressure (BP) lowering effects of treatment with continuous positive airway pressure (CPAP) or placebo (nasal strips) for 6 months in adult patients with uncontrolled hypertension (HTN) and moderate-to-severe obstructive sleep apnea (OSA). Patients using at least one antihypertensive medication were included. Uncontrolled HTN was confirmed by at least one abnormal parameter in the 24-hour ABPM and ≥80% medication adherence evaluated by pill counting after the run-in period. OSA was defined by an apnea-hypopnea index ≥15 events/hours. The co-primary endpoints are brachial BP (office and ambulatory BP monitoring, ABPM) and central BP. Secondary outcomes include hypertension-mediated organ damage (HMOD) to heart, aorta, eye, and kidney. We pre-specified several sub-studies from this investigation. Visits occur once a week in the first month and once a month thereafter. The programmed sample size was 176 patients but the pandemic prevented this final target. A post-hoc power analysis will be calculated from the final sample. ClinicalTrials.gov: NCT02270658.

RESULTS

The first 100 patients are predominantly males (n=69), age: 52±10 years, body mass index: 32.7±3.9 kg/m2 with frequent co-morbidities.

CONCLUSIONS

The MORPHEOS trial has a unique study design including a run-in period; pill counting, and detailed analysis of hypertension-mediated organ damage in patients with uncontrolled HTN that will allow clarification of the impact of OSA treatment with CPAP.

Transfer-function-free technique for the noninvasive determination of the human arterial pressure waveform

The estimation of central aortic blood pressure is a cardinal measurement, carrying effective physiological, and prognostic data beyond routine peripheral blood pressure. Transfer function-based devices effectively estimate aortic systolic and diastolic blood pressure from peripheral pressure waveforms, but the reconstructed pressure waveform seems to preserve features of the peripheral waveform. We sought to develop a new method for converting the local diameter distension waveform into a pressure waveform, through an exponential function whose parameters depend on the local wave speed. The proposed method was then tested at the common carotid artery. Diameter and blood velocity waveforms were acquired via ultrasound at the right common carotid artery while simultaneously recording pressure at the left common carotid artery via tonometer in 203 people (122 men, 50 ± 18 years). The wave speed was noninvasively estimated via the lnDU-loop method and then used to define the exponential function to convert the diameter into pressure. Noninvasive systolic and mean pressures estimated by the new technique were 3.8 ± 21.8 (p = 0.015) and 2.3 ± 9.6 mmHg (p = 0.011) higher than those obtained using tonometery. However, differences were much reduced and not significant in people >35 years (0.6 ± 18.7 and 0.8 ± 8.3 mmHg, respectively). This proof of concept study demonstrated that local wave speed, estimated from noninvasive local measurement of diameter and flow velocity, can be used to determine an exponential function that describes the relationship between local pressure and diameter. This pressure-diameter function can then be used for the noninvasive estimation of local arterial pressure.

Flexible Wearable Sensors for Cardiovascular Health Monitoring

Cardiovascular diseases account for the highest mortality globally, but recent advances in wearable technologies may potentially change how these illnesses are diagnosed and managed. In particular, continuous monitoring of cardiovascular vital signs for early intervention is highly desired. To this end, flexible wearable sensors that can be comfortably worn over long durations are gaining significant attention. In this review, advanced flexible wearable sensors for monitoring cardiovascular vital signals are outlined and discussed. Specifically, the functional materials, configurations, mechanisms, and recent advances of these flexible sensors for heart rate, blood pressure, blood oxygen saturation, and blood glucose monitoring are highlighted. Different mechanisms in bioelectric, mechano-electric, optoelectric, and ultrasonic wearable sensors are presented to monitor cardiovascular vital signs from different body locations. Present challenges, possible strategies, and future directions of these wearable sensors are also discussed. With rapid development, these flexible wearable sensors will potentially be applicable for both medical diagnosis and daily healthcare use in tackling cardiovascular diseases.

Soft Wearable Healthcare Materials and Devices

In spite of advances in electronics and internet technologies, current healthcare remains hospital-centred. Disruptive technologies are required to translate state-of-art wearable devices into next-generation patient-centered diagnosis and therapy. In this review, recent advances in the emerging field of soft wearable materials and devices are summarized. A prerequisite for such future healthcare devices is the need of novel materials to be mechanically compliant, electrically conductive, and biologically compatible. It is begun with an overview of the two viable design strategies reported in the literatures, which is followed by description of state-of-the-art wearable healthcare devices for monitoring physical, electrophysiological, chemical, and biological signals. Self-powered wearable bioenergy devices are also covered and sensing systems, as well as feedback-controlled wearable closed-loop biodiagnostic and therapy systems. Finally, it is concluded with an overall summary and future perspective.

Association of central arterial blood pressure and left ventricular hypertrophy in patients with chronic kidney disease

AIMS

In the general population, central arterial blood pressure has proved to be more closely related to left ventricular hypertrophy (LVH) than brachial arterial blood pressure. We aimed to investigate whether this relationship was true in patients with chronic kidney disease (CKD).

METHODS

In this retrospective study, we reviewed the medical records of 289 adult patients with CKD from the Zhejiang Provincial People's Hospital in Zhejiang, China. Demographic, echocardiographic and brachial and central blood pressure parameters were retrieved from medical records. Central blood pressure was measured using the SphygmoCor® CvMS (AtCor, Australia) device and its corresponding software. Multivariate logistic regression analyses were performed to identify independent predictors of LVH. Receiver operating characteristic curves were used to determine the ability of central and brachial blood pressure to predict LVH.

RESULTS

The left ventricular mass index was positively associated with both central and brachial blood pressures. However, multiple logistic regression analysis demonstrated that a central pulse pressure (CPP) ≥ 58 mm Hg was an independent risk factor for LVH (OR = 5.597, 95%CI 2.363-13.259, p < .001). Brachial pulse pressure is not superior to CPP in predicting LVH (area under the curve [AUC] = 0.695, 95%CI 0.634-0.756, p < .001 vs. AUC = 0.687, 95%CI: 0.626-0.748, p < .001, respectively; p = .4824).

CONCLUSION

Our results suggested that, similarly to the general population, CPP is a better parameter for predicting the occurrence of LVH in patients with CKD.

Central Over Peripheral Blood Pressure: An Emerging Issue in Hypertension Research

Measurement of blood pressure is one of the most important and powerful clinical tools in clinical practice. Physicians use the classical method that was introduced more than 100 years ago with the emergence of the brachial cuff sphygmomanometer. The use of this method, despite its initial setbacks, spread like fire throughout the medical community with the boost by the early adoption by insurance companies to assess risk as well as the ease of use, the availability with the wide variety of devices, the good reproducibility and its predictive role. However, a long-forgotten dispute between measurements of peripheral (brachial) and central (aortic, carotid) blood pressure has resurfaced after the introduction of techniques and devices that can easily and accurately estimate non-invasively the central pressure waveform. Clinicians, until recently, focussed only on the pressure waveform trough (diastole) and peak (systole), ignoring the possible information provided by the rest of the arterial pressure waveform. Several restrictions exist with peripheral blood pressures measured with either an oscillometric or a sphygmomanometer device that blur the existing image of the ideal biomarker to describe the haemodynamic characteristics of the cardiovascular system. On the other hand, central pressures seem to be more pathophysiologically relevant to end-organ damage of the brain, heart and kidneys and on future events. Furthermore, measurement of the central waveform can provide clinically useful information, like the quantification of wave reflections with augmentation index, beyond blood pressure measured in the brachial artery. This article will explain the pathophysiological mechanisms linking central pressures to cardiovascular outcomes, review the evidence for the use of central blood pressure over peripheral pressures, elaborate on the prognostic role of central blood pressures and finally review the latest developments on the pharmacological modulation of central blood pressures.

Higher habitual dietary flavonoid intake associates with lower central blood pressure and arterial stiffness in healthy older adults

Flavonoids have shown anti-hypertensive and anti-atherosclerotic properties: the impact of habitual flavonoid intake on vascular function, central haemodynamics and arterial stiffness may be important. We investigated the relationship between habitual flavonoid consumption and measures of central blood pressure and arterial stiffness. We performed cross-sectional analysis of 381 non-smoking healthy older adults (mean age 66·0 (sd 4·1) years; BMI, 26·4 (sd 4·41) kg/m2; 41 % male) recruited as part of the Australian Research Council Longevity Intervention study. Flavonoid intake (i.e. flavonols, flavones, flavanones, anthocyanins, isoflavones, flavan-3-ol monomers, proanthocyanidins, theaflavins/thearubigins and total consumption) was estimated from FFQ using the US Department of Agriculture food composition databases. Measures of central haemodynamics and arterial stiffness included systolic blood pressure (cSBP), diastolic blood pressure (cDBP), mean arterial pressure (cMAP) and augmentation index (cAIx). After adjusting for demographic and lifestyle confounders, each sd/d higher intake of anthocyanins ((sd 44·3) mg/d) was associated with significantly lower cDBP (-1·56 mmHg, 95 % CI -2·65, -0·48) and cMAP (-1·62 mmHg, 95 % CI -2·82, -0·41). Similarly, each sd/d higher intake of flavanones ((sd 19·5) mg/d) was associated with ~1 % lower cAIx (-0·93 %, 95 % CI -1·77, -0·09). These associations remained significant after additional adjustment for (1) a dietary quality score and (2) other major nutrients that may affect blood pressure or arterial stiffness (i.e. Na, K, Ca, Mg, n-3, total protein and fibre). This study suggests a possible benefit of dietary anthocyanin and flavanone intake on central haemodynamics and arterial stiffness; these findings require corroboration in further research.

Association of free fatty acid binding protein with central aortic stiffness, myocardial dysfunction and preserved ejection fraction heart failure

There is an established link between cardiometabolic abnormality, central arterial stiffness, and preserved ejection fraction heart failure (HFpEF). Adipocyte free fatty acid binding protein (a-FABP) has been shown to signal endothelial dysfunction through fatty acid toxicity, though its role in mediating ventricular-arterial dysfunction remains unclear. We prospectively examined the associations of a-FABP with central arterial pressure using non-invasive applanation tonometry (SphygmoCor) and cardiac structure/function (i.e., tissue Doppler imaging [TDI] and global longitudinal myocardial strain [GLS]) in patients with cardiometabolic (CM) risk (n = 150) and HFpEF (n = 50), with healthy volunteers (n = 49) serving as a control. We observed a graded increase of a-FABP across the healthy controls, CM individuals, and HFpEF groups (all paired p < 0.05). Higher a-FABP was independently associated with higher central systolic and diastolic blood pressures (CSP/CPP), increased arterial augmentation index (Aix), lower early myocardial relaxation velocity (TDI-e'), higher left ventricle (LV) filling (E/TDI-e') and worsened GLS (all p < 0.05). During a median of 3.85 years (interquartile range: 3.68-4.62 years) follow-up, higher a-FABP (cutoff: 24 ng/mL, adjusted hazard ratio: 1.01, 95% confidence interval: 1.001-1.02, p = 0.04) but not brain natriuretic peptide, and higher central hemodynamic indices were related to the incidence of heart failure (HF) in fully adjusted Cox models. Furthermore, a-FABP improved the HF risk classification over central hemodynamic information. We found a mechanistic pathophysiological link between a-FABP, central arterial stiffness, and myocardial dysfunction. In a population with a high metabolic risk, higher a-FABP accompanied by worsened ventricular-arterial coupling may confer more unfavorable outcomes in HFpEF.

Central blood pressure lowering effect of telmisartan-rosuvastatin single-pill combination in hypertensive patients combined with dyslipidemia: A pilot study

This multicenter, phase 4, Prospective Randomized Open, Blinded End‐point (PROBE) study aimed to evaluate safety and efficacy of telmisartan/rosuvastatin single‐pill combination (SPC) therapy on lowering central blood pressure (BP) compared with telmisartan monotherapy in hypertensive patients with dyslipidemia in Korea. Study was terminated earlier than planned due to COVID‐19 pandemic, thus should be considered as a pilot study. Among 125 patients who met the inclusion criteria of hypertension and dyslipidemia (defined as 10‐year Atherosclerotic Cardiovascular Disease risk score over 5%), 80 patients went through 4‐week single‐group run‐in period with telmisartan 40–80 mg, then randomized to telmisartan 80 mg + rosuvastatin (10 or 20 mg) SPC group or telmisartan 80 mg monotherapy group. The central/brachial BP, brachial‐ankle pulse wave velocity (baPWV), and augmentation index (AIx) were assessed at baseline and 16 weeks later. Mean brachial SBP changed from 135.80 ± 14.22 mmHg to 130.69 ± 13.23 mmHg in telmisartan/rosuvastatin group and from 134.37 ± 12.50 mmHg to 133.75 ± 12.30 mmHg in telmisartan monotherapy group without significant difference (between‐group difference p = .149). Mean central SBP were reduced significantly in the telmisartan/rosuvastatin group with change from 126.72 ± 14.44 mmHg to 121.56 ± 14.56 mmHg while telmisartan monotherapy group showed no significant change (between‐group difference p = .028). BaPWV changed from 1672.57 ± 371.72 m/s to 1591.75 ± 272.16 m/s in telmisartan/rosuvastatin group and from 1542.85 ± 263.70 m/s to 1586.12 ± 297.45 m/s in telmisartan group with no significance (between‐group difference p = .078). Change of AIx had no significant difference (between‐group difference p = .314). Both groups showed excellent compliance rate of 96.9 ± 4.5% with no significant difference in adverse rate. Telmisartan/rosuvastatin SPC therapy was more effective in lowering central BP compared with the telmisartan monotherapy. The results of this study showed benefit of additive statin therapy in hypertensive patients combined with dyslipidemia.

Patient preferences for ambulatory blood pressure monitoring devices: Wrist-type or arm-type?

BACKGROUND

Ambulatory blood pressure monitoring (ABPM) is important in evaluating average 24-hour blood pressure (BP) levels, circadian rhythm, sleeping BP and BP variability but many patients are reluctant to use standard ABPM devices.

METHODS

We compared two validated ABPM devices, the BPro tonometric wrist monitor and the A&D TM-2430 oscillometric upper arm monitor, for agreement of recordings and acceptability in 37 hypertensive patients (aged 55±9 years).

RESULTS

Successful BP measurements were less frequent with the wrist-type than the arm-type device during the sleeping (66.3% vs. 92.9%, P <0.01) and awake periods (56.2% vs. 86.5%, P <0.01). Comparable paired readings showed no significant difference in systolic BP but diastolic BP (DBP) values were higher with the wrist compared to the arm monitor (24-hour 89±13 vs. 85±14 mmHg, P <0.01) with similar differences awake and sleeping. Bland-Altman analysis showed some large discrepancies between individual arm and wrist monitor measurements. More patients found the wrist monitor more comfortable to use than the arm monitor.

CONCLUSIONS

Despite the difference in individual BP measurements and the systematic overestimation of DBP values with the BPro device, wrist monitors with good patient acceptability may be useful to facilitate ABPM in some patients to provide additional information about cardiovascular risk and response to antihypertensive therapies.

The effect of left ventricular contractility on arterial hemodynamics: A model-based investigation

Ventricular-arterial coupling is a major determinant of cardiovascular performance, however, there are still inherent difficulties in distinguishing ventricular from vascular effects on arterial pulse phenotypes. In the present study, we employed an extensive mathematical model of the cardiovascular system to investigate how sole changes in cardiac contractility might affect hemodynamics. We simulated two physiologically relevant cases of high and low contractility by altering the end-systolic elastance, E_es, (3 versus 1 mmHg/mL) under constant cardiac output and afterload, and subsequently performed pulse wave analysis and wave separation. The aortic forward pressure wave component was steeper for high E_es, which led to the change of the total pressure waveform from the characteristic Type A phenotype to Type C, and the decrease in augmentation index, AIx (-2.4% versus +18.1%). Additionally, the increase in E_es caused the pulse pressure amplification from the aorta to the radial artery to rise drastically (1.86 versus 1.39). Our results show that an increase in cardiac contractility alone, with no concomitant change in arterial properties, alters the shape of the forward pressure wave, which, consequently, changes central and peripheral pulse phenotypes. Indices based on the pressure waveform, like AIx, cannot be assumed to reflect only arterial properties.

Clinical and central hemodynamic characteristics of early adulthood isolated diastolic hypertension: a comparison with isolated systolic hypertension

OBJECTIVES

Knowledge on early adulthood isolated diastolic hypertension (IDH) is limited. We compared the clinical and central hemodynamic characteristics of early adulthood IDH, isolated systolic hypertension (ISH) and normotension.

METHODS

A total of 509 untreated young adults (18-35 years) who underwent ambulatory blood pressure monitoring (ABPM; ABPM cohort), 148 who underwent both ABPM and applanation tonometry (ABPM-tonometry cohort) and 26 newly recruited normotensives were analyzed. Their pulse wave images were analyzed after categorizing them into type A vs. B vs. C.

RESULTS

In the ABPM cohort (men, 86.6%), systolic-diastolic hypertension was the most common subtype (68.0%), while IDH was the rarest (5.1%). The subtype composition showed age-dependency; the proportion of IDH and systolic-diastolic hypertension increased across the age tertiles, while that of ISH declined. Patients with IDH were significantly older and shorter than those with ISH. Despite having a significantly lower 24-h average systolic blood pressure (SBP), patients with IDH exhibited discordantly high central systolic blood pressures at levels comparable to those of patients with ISH. Pulse pressure amplification was the lowest in patients with IDH and highest in those with ISH (P < 0.001), accounting for the discordance. Augmentation index differed significantly between them (P < 0.016). The waveform composition differed across the subtypes (type A vs. B/C: IDH = 61.5 vs. 38.5%; ISH = 3.0 vs. 97.0%; normotension = 30.8 vs. 69.2%, P < 0.001); the averaged waveform plots demonstrated a clear morphological disparity between IDH (type A) and ISH (type B/C).

CONCLUSIONS

Early adulthood IDH is a unique entity clearly distinguishable from ISH in terms of clinical and central hemodynamic characteristics.

Comparison of Brachial Blood Pressure and Central Blood Pressure in Attended, Unattended, and Unattended Standing Situations

Central systolic blood pressure (cSBP) is an independent predictor of future cardiovascular disease. Unattended brachial SBP (bSBP) can eliminate the white-coat effect. However, unattended cSBP and unattended standing cSBP have never been reported. We aimed to compare bSBP and cSBP in attended, unattended, and unattended standing situations. We also aimed to compare the white-coat effect and unattended orthostatic BP change between bSBP and cSBP. Altogether, 104 hypertensive outpatients were included (mean age: 66.0 ± 9.8 years, 41.3% male, mean body mass index: 25.0 ± 4.5). Attended bSBP/cSBP values were 127.3 ± 15.7/119.2 ± 15.0, unattended bSBP/cSBP values were 122.7 ± 15.3/114.4 ± 15.1, and unattended standing bSBP/cSBP values were 123.6 ± 15.7/114.1 ± 14.8 mmHg (correlation coefficients/coefficients of determination between bSBP and cSBP: 0.971/0.943, 0.970/0.941, and 0.964/0.929, respectively; all p < 0.001). No significant difference was observed in the white-coat effect between bSBP and cSBP (4.6 ± 5.8 vs. 4.8 ± 5.7 mmHg). Although there was no significant difference between unattended sitting SBP and unattended standing SBP in terms of both bSBP and cSBP, a numerically small but significant difference was observed in the unattended orthostatic BP change between bSBP and cSBP (0.9 ± 8.0 vs. -0.3 ± 9.0 mmHg, p = 0.002). In conclusion, significant and strong correlations were observed between bSBP and cSBP in attended, unattended, and unattended standing BP measurements. The white-coat effect on bSBP was equivalent to that on cSBP. There was a numerically small but significant difference in the unattended orthostatic BP change between bSBP and cSBP.

Individual changes of central blood pressure in response to upright posture: different hemodynamic phenotypes

OBJECTIVES

Most studies about upright regulation of blood pressure have focused on orthostatic hypotension despite the diverse hemodynamic changes induced by orthostatic challenge. We investigated the effect of passive head-up tilt on aortic blood pressure.

METHODS

Noninvasive peripheral and central hemodynamics in 613 volunteers without cardiovascular morbidities or medications were examined using pulse wave analysis, whole-body impedance cardiography and heart rate variability analysis.

RESULTS

In all participants, mean aortic SBP decreased by -4 (-5 to -3) mmHg [mean (95% confidence intervals)] and DBP increased by 6 (5--6) mmHg in response to upright posture. When divided into tertiles according to the supine-to-upright change in aortic SBP, two tertiles presented with a decrease [-15 (-14 to -16) and -4 (-3 to -4) mmHg, respectively] whereas one tertile presented with an increase [+7 (7-- 8) mmHg] in aortic SBP. There were no major differences in demographic characteristics between the tertiles. In regression analysis, the strongest explanatory factors for upright changes in aortic SBP were the supine values of, and upright changes in systemic vascular resistance and cardiac output, and supine aortic SBP.

CONCLUSION

In participants without cardiovascular disease, the changes in central SBP during orthostatic challenge are not uniform. One-third presented with higher upright than supine aortic SBP with underlying differences in the regulation of systemic vascular resistance and cardiac output. These findings emphasize that resting blood pressure measurements give only limited information about the blood pressure status.

Vascular Ageing in Youth: A Call to Action

Extensive evidence shows that risk factors for cardiovascular disease (CVD) begin to develop early in life. Childhood obesity and elevated blood pressure (BP) have become overwhelmingly challenging, with 57% of today's children predicted to be obese by the age of 35 years, and global rates of hypertension in children and adolescents increasing by 75% from 2000 to 2015. Thus, there is an urgent need for tools that can assess early CVD risk in youth, which may lead to better risk stratification, preventative intervention, and personalised medicine. Vascular ageing (the deterioration in vascular structure and function) is a pivotal progenitor of health degeneration associated with elevated BP. Exposure to adverse environmental and genetic factors from fetal life promotes the development and accumulation of subclinical vascular changes that direct an individual towards a trajectory of early vascular ageing (EVA)-an independent predictor of target organ damage in the heart, brain, and kidneys. Therefore, characterising vascular ageing from youth may provide a window into cardiovascular risk later in life. However, vascular ageing measurements only have value when techniques are accurate/validated and when reliable thresholds are available for defining normal ranges and ranges that signal increased risk of disease. The aim of this paper is to summarise current evidence on the importance of vascular ageing assessment in youth and the impact of interventions to prevent or delay EVA, to highlight the need for standardisation and validation of measurement techniques in children and adolescents, and the importance of establishing reference values for vascular ageing measures in this population.

Office, Central, and Ambulatory Blood Pressure for Predicting First Stroke in Older Adults: A Community-Based Cohort Study

[Figure: see text].

Pathophysiology and consequences of arterial stiffness in children with chronic kidney disease

Changes in arterial structure and function are seen early in the course of chronic kidney disease (CKD) and have been causally associated with cardiovascular (CV) morbidity. Numerous potential injuries encompassing both traditional and uremia-specific CV risk factors can induce structural arterial changes and accelerate arterial stiffening. When the buffering capacity of the normally elastic arteries is reduced, damage to vulnerable microcirculatory beds can occur. Moreover, the resultant increase to cardiac afterload contributes to the development of left ventricular hypertrophy and cardiac dysfunction. Adult studies have linked arterial stiffness with increased risk of mortality, CV events, cognitive decline, and CKD progression. Pulse wave velocity (PWV) is currently the gold standard of arterial stiffness assessment but its measurement in children is challenging due to technical difficulties and physiologic aspects related to growth and poor standardization between algorithms for calculating PWV. Nevertheless, studies in pediatric CKD have reported increased arterial stiffness in children with advanced CKD, on dialysis, and after kidney transplantation. Development of arterial stiffness in children with CKD is closely related to mineral-bone disease and hypertension, but other factors may also play a significant role. The clinical relevance of accelerated arterial stiffness in childhood on cardiovascular outcomes in adult life remains unclear, and prospective studies are needed. In this review we discuss mechanisms leading to arterial stiffness in CKD and its clinical implications, along with issues surrounding the technical aspects of arterial stiffness assessment in children.

The effect of acute aerobic exercise on central arterial stiffness, wave reflections, and hemodynamics in adults with diabetes: A randomized cross-over design

BACKGROUND

Individuals with diabetes have greater central arterial stiffness, wave reflections, and hemodynamics, all of which promote the accelerated cardiovascular pathology seen in this population. Acute aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness, wave reflections, and hemodynamics in healthy individuals; however, the effects of acute aerobic exercise in reducing these outcomes is not well established in people with diabetes. Recently, implementation of high-intensity interval exercise (HIIE) has shown superior improvements in cardiovascular health outcomes when compared to traditional aerobic exercise. Yet, the effect of HIIE on the aforementioned outcomes in people with diabetes is not known. The purpose of this study was to (i) describe the central arterial stiffness, wave reflections, and hemodynamic responses to a bout of HIIE and moderate-intensity continuous exercise (MICE) in adults with diabetes; and (ii) compare the effects of HIIE and MICE on the aforementioned outcomes.

METHODS

A total of 24 adult men and women (aged 29-59 years old) with type 1 (n = 12) and type 2 (n = 12) diabetes participated in a randomized cross-over study. All participants completed the following protocols: (i) HIIE: cycling for 4 × 4 min at 85%-95% of heart rate peak (HR_peak), interspersed with 3 min of active recovery at 60%-70%HR_peak; (ii) MICE: 33 min of continuous cycling at 60%-70%HR_peak; and (iii) control (CON): lying quietly in a supine position for 30 min.

RESULTS

A significant group × time effect was found for changes in central systolic blood pressure (F = 3.20, p = 0.01) with a transient reduction for the HIIE group but not for the MICE or CON groups. There was a significant group × time effect for changes in augmentation index at a heart rate of 75 beats/min (F = 2.32, p = 0.04) with a decrease following for HIIE and MICE but not for CON. For all other measures of central arterial stiffness and hemodynamics, no significant changes were observed (p > 0.05).

CONCLUSION

A bout of HIIE appears to lead to a greater transient reduction in central systolic blood pressure than the reduction observed following MICE; however, both HIIE and MICE improved augmentation index at a heart rate of 75 beats/min in people with diabetes. There was no significant difference in response to HIIE and MICE in all outcomes. This provides preliminary evidence on the role of HIIE on such outcomes in people with diabetes.

Could arterial stiffness be early reversible target organ damage test in childhood hypertension?

OBJECTIVE

The recommended treatment for hypertension (HTN) in children has been revised recently. This study aimed to present the changes in target organ damage (TOD) and arterial stiffness parameters after treatment in children with primary HTN who were managed in accordance with the 2016 European Society of Hypertension Guidelines.

METHODS

Patients with primary HTN included in this study were newly diagnosed, untreated, and were followed-up for a minimum of 6 months. HTN was confirmed by 24-h ambulatory blood pressure monitoring (ABPM). All patients underwent the following assessments: anthropometrical measurements of body mass index (BMI), carotid intima-media thickness (cIMT), left ventricular mass index (LVMI), plasma creatinine, urea, electrolytes, uric acid, fasting plasma glucose, blood lipids, urinalysis, urine culture, and first morning urine albumin tocreatinine ratio. The ABPM device performed measurements such as central blood pressure (cBP) and pulse wave velocity (PWV).

RESULTS

Thirty-two of 104 patients were enrolled. Seventeen patients were male, and 53% were obese. Compared with pretreatment, creatinine, urea, systolic BP (SBP), diastolic BP (DBP), systolic load, diastolic load, central SBP (cSBP), cSBP z score, cDBP, and PWV z score decreased, whereas LVMI and BMI z scores were unchanged.

CONCLUSION

After BP improvement, while LVMI did not regress, the cSBP, cSBP z, and PWV z score values, which are markers of arterial stiffness, regressed. This supports the corrective effect of BP control on the cardiovascular system even in a short-term follow-up. Further longitudinal studies are needed for the assessment of BP control on arterial stiffness in childhood.