Late systolic central hypertension as a predictor of incident heart failure: the Multi-ethnic Study of Atherosclerosis

Computing pulsatile blood flow of coronary artery under incomplete boundary conditions

BACKGROUND

Accurate measurement of pulsatile blood flow in the coronary arteries enables coronary wave intensity analysis, which can serve as an indicator for assessing coronary artery physiology and myocardial viability. Computational fluid dynamics (CFD) methods integrating coronary angiography images and fractional flow reserve (FFR) offer a novel approach for computing mean coronary blood flow. However, previous methods neglect the inertial effect of blood flow, which may have great impact on pulsatile blood flow calculation. To improve the accuracy of pulsatile blood flow calculation, a novel CFD based method considering the inertia term is proposed.

METHODS

A flow resistance model based on Pressure-Flow vs.Time curves is proposed to model the resistance of the epicardial artery. The parameters of the flow resistance model can be fitted from the simulated pulsating flow rates and pressure drops of a specific mode. Then, pulsating blood flow can be calculated by combining the incomplete pressure boundary conditions under pulsating conditions which are easily obtained in clinic. Through simulation experiments, the effectiveness of the proposed method is validated in idealized and reconstructed 3D model of coronary artery. The impacts of key parameters for generating the simulated pulsating flow rates and pressure drops on the accuracy of pulsatile blood flow calculation are also investigated.

RESULTS

For the idealized model, the previously proposed Pressure-Flow model has a significant leading effect on the computed blood flow waveform in the moderate model, and this leading effect disappears with the increase of the degree of stenosis. The improved model proposed in this paper has no leading effect, the root mean square error (RMSE) of the proposed model is low (the left coronary mode:≤0.0160, the right coronary mode:≤0.0065) for all simulated models, and the RMSE decreases with an increase of stenosis. The RMSE is consistently small (≤0.0217) as the key parameters of the proposed method vary in a large range. It is verified in the reconstructed model that the proposed model significantly reduces the RMSE of patients with moderate stenosis (the Pressure-Flow model:≤0.0683, the Pressure-Flow vs.Time model:≤0.0297), and the obtained blood flow waveform has a higher coincidence with the simulated reference waveform.

CONCLUSIONS

This paper confirms that ignoring the effect of inertia term can significantly affect the accuracy of calculating pulsatile blood flow in moderate stenosis lesions, and the new method proposed in this paper can significantly improves the accuracy of calculating pulsatile blood flow in moderate stenosis lesions. The proposed method provides a convenient clinical method for obtaining pressure-synchronized blood flow, which is expected to facilitate the application of waveform analysis in the diagnosis of coronary artery disease.

Blood pressure, hypertension, and the risk of heart failure: a systematic review and meta-analysis of cohort studies

AIMS

Several observational studies have investigated the association between hypertension or elevated systolic blood pressure and diastolic blood pressure and risk of heart failure, but not all the studies have been consistent. This systematic review and meta-analysis aimed to summarize the available data from cohort studies on the association between hypertension, systolic and diastolic blood pressure, and the risk of heart failure.

METHODS AND RESULTS

PubMed and Embase databases were searched for relevant articles from inception to 10 June 2022. Cohort studies on hypertension or blood pressure and heart failure were included. Random effect models were used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs) for the association between hypertension or blood pressure and heart failure. Forty-seven cohort studies were included. The summary RR was 1.71 (95% CI: 1.53-1.90, I2 = 98.4%) for hypertension vs. no hypertension (n = 43 studies, 166 798 cases, 20 359 997 participants), 1.28 (95% CI: 1.22-1.35, I2 = 90.3%) per 20 mmHg of systolic blood pressure (24 studies, 31 639 cases and 2 557 975 participants), and 1.12 (95% CI: 1.04-1.21, I2 = 92.6%) per 10 mmHg of diastolic blood pressure (16 studies, 23 127 cases and 2 419 972 participants). There was a steeper increase in heart failure risk at higher blood pressure levels and a three- to five-fold increase in RR at around 180/120 mmHg of systolic and diastolic blood pressure compared with 100/60 mmHg, respectively. There was little indication of publication bias across analyses.

CONCLUSION

This meta-analysis suggests a strong positive association between hypertension and systolic and diastolic blood pressure and the risk of heart failure. These results support efforts to reduce blood pressure in the general population to reduce the risk of heart failure.

Superiority of a Representative MRI Flow Waveform over Doppler Ultrasound for Aortic Wave Reflection Assessment in Children and Adolescents With/Without a History of Heart Disease

Wave separation analysis (WSA) reveals the impact of forward- and backward-running waves on the arterial pressure pulse, but the calculations require a flow waveform. This study investigated (1) the variability of the ascending aortic flow waveform in children and adolescents with/without a childhood heart disease history (CHD); (2) the accuracy of WSA obtained with a representative flow waveform (RepFlow), compared with the triangulation method and published ultrasound-derived adult representative flow; (3) the impact of limitations in Doppler ultrasound on WSA; and (4) generalizability of results to adults with a history of CHD. Phase contrast MRI was performed in youth without (n = 45, Group 1, 10-19 years) and with CHD (n = 79, Group 2, 7-18 years), and adults with CHD history (n = 29, Group 3, 19-59 years). Segmented aortic cross-sectional area was used as a surrogate for the central pressure waveform in WSA. A subject-specific virtual Doppler ultrasound was performed on MRI data by extracting velocities from a sample volume. Time/amplitude-normalized ascending aortic flow waveforms were highly consistent amongst all groups. WSA with RepFlow therefore yielded errors < 10% in all groups for reflected wave magnitude and return time. Absolute errors were typically 1.5-3 times greater with other methods, including subject-specific (best-case/virtual) Doppler ultrasound, for which velocity profile skewing introduced waveform errors. Our data suggest that RepFlow is the optimal approach for pressure-only WSA in children and adolescents with/without CHD, as well as adults with CHD history, and may even be more accurate than subject-specific Doppler ultrasound in the ascending aorta.

The association between arterial compliance, as assessed by PTC1 and PTC2 from radial artery waveforms, and age, sex, and race/ethnicity

BACKGROUND

There is limited literature on differences in arterial compliance, as assessed from arterial pressure waveforms, with age, sex, and race/ethnicity. PTC1 and PTC2 are indices of arterial compliance, which are derived from a Windkessel model of the waveform, relatively easy to obtain, and associated with cardiovascular disease.

METHOD

PTC1 and PTC2 were computed from radial artery waveforms from participants of the Multi-Ethnic Study of Atherosclerosis at baseline and again 10 years later. We evaluated the association of PTC1, PTC2, and 10-year change in PTC1 and PTC2 with age, sex, and race/ethnicity.

RESULTS

Among 6245 participants in 2000-2002 (mean ± SD of age was 62 ± 10 years; 52% female; 38% White, 12% Chinese, 27% Black, and 23% Hispanic/Latino), means ± SDs for PTC1 and PTC2 were 394 ± 334 and 94 ± 46 ms. After adjustment for cardiovascular disease risk factors, mean PTC2 was 1.1 ms (95% confidence interval: 1.0, 1.2) lower (arterial stiffness was greater) per year older age, was 22 ms (19, 24) lower for females, and varied by race/ethnicity ( P  < 0.001; e.g., 5 ms lower for Blacks compared with Whites), although the differences were smaller at older ages ( P  < 0.001 for age-sex, P  < 0.001 for age-race/ethnicity interactions). Among 3701 participants with repeat measurements in 2010-2012, arteries had stiffened (mean ± SD 10-year decrease in PTC2: 13 ± 46 ms) consistent with cross-sectional age-trend and tended to stiffen less for females and Blacks consistent with cross-sectional age-interactions.

CONCLUSION

Differences in arterial compliance by age, sex, and race/ethnicity lend support to identify and act on societal factors that may drive health disparities.

Estimated pulse wave velocity and incident heart failure and its subtypes: Findings from the multi-ethnic study of atherosclerosis

Age-associated increase in aortic stiffness, measured as carotid-femoral pulse wave velocity (PWV), is an important effector of cardiac damage and heart failure (HF). Pulse wave velocity estimated from age and blood pressure (ePWV) is emerging as a useful proxy of vascular aging and subsequent cardiovascular disease risk. We examined the association of ePWV with incident HF and its subtypes in a large community sample of 6814 middle-aged and older adults from the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

Participants with an ejection fraction ≤40 % were classified as HF with reduced ejection fraction (HFrEF) while those with an ejection fraction ≥50 % were classified as HF with preserved ejection fraction (HFpEF). Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95 % confidence intervals (CI).

RESULTS

Over a mean follow-up period of 12.5 years, incident HF was diagnosed in 339 participants: 165 were classified as HFrEF and 138 as HFpEF. In fully adjusted models, the highest quartile of ePWV was significantly associated with an increased risk of overall HF (HR 4.79, 95 % CI 2.43-9.45) compared with the lowest quartile (reference). When exploring HF subtypes, the highest quartile of ePWV was associated with HFrEF (HR 8.37, 95 % CI 4.24-16.52) and HFpEF (HR 3.94, 95 % CI 1.39-11.17).

CONCLUSIONS

Higher ePWV values were associated with higher rates of incident HF and its subtypes in a large, diverse cohort of men and women.

Is It Good to Have a Stiff Aorta with Aging? Causes and Consequences

Aortic stiffness increases with advancing age, more than doubling during the human life span, and is a robust predictor of cardiovascular disease (CVD) clinical events independent of traditional risk factors. The aorta increases in diameter and length to accommodate growing body size and cardiac output in youth, but in middle and older age the aorta continues to remodel to a larger diameter, thinning the pool of permanent elastin fibers, increasing intramural wall stress and resulting in the transfer of load bearing onto stiffer collagen fibers. Whereas aortic stiffening in early middle age may be a compensatory mechanism to normalize intramural wall stress and therefore theoretically "good" early in the life span, the negative clinical consequences of accelerated aortic stiffening beyond middle age far outweigh any earlier physiological benefit. Indeed, aortic stiffness and the loss of the "windkessel effect" with advancing age result in elevated pulsatile pressure and flow in downstream microvasculature that is associated with subclinical damage to high-flow, low-resistance organs such as brain, kidney, retina, and heart. The mechanisms of aortic stiffness include alterations in extracellular matrix proteins (collagen deposition, elastin fragmentation), increased arterial tone (oxidative stress and inflammation-related reduced vasodilators and augmented vasoconstrictors; enhanced sympathetic activity), arterial calcification, vascular smooth muscle cell stiffness, and extracellular matrix glycosaminoglycans. Given the rapidly aging population of the United States, aortic stiffening will likely contribute to substantial CVD burden over the next 2-3 decades unless new therapeutic targets and interventions are identified to prevent the potential avalanche of clinical sequelae related to age-related aortic stiffness.

Evaluation of the haematinic, antioxidant and anti-atherosclerotic potential of Momordica charantia in cholesterol-fed experimental rats

Background

Purpose

Methods

Results

Conclusion

•

M. charantia is a medicinal herb whose extract exhibits anti-atherosclerotic properties.

•

The herb maintained the functional and structural integrity of the aorta.

•

It protects against oxidative stress and mediates inflammation.

•

Its effects are comparable to that of the standard drug, Atovastatin.

The association between indices of blood pressure waveforms (PTC1 and PTC2) and incident heart failure

OBJECTIVES

The radial artery pulse waveform is a continuous measure of pressure throughout the cardiac cycle, and thus can provide more information than just systolic and diastolic blood pressures. New indices based on a Windkessel model of the waveform, PTC1 and PTC2, are related to arterial compliance and add information for prediction of incident cardiovascular disease (coronary heart disease, stroke, myocardial infarction) but their association with heart failure is unknown.

METHODS

Among 6229 adults (mean age 62 years) from four race/ethnic groups who were initially free of clinical cardiovascular disease and heart failure in 2000-2002, we evaluated the associations of baseline PTC1 and PTC2 with incident heart failure.

RESULTS

Mean ± standard deviation PTC1 and PTC2 were 394 ± 334 and 94 ± 46 ms, respectively. During a median of 15.7 years follow-up, there were 357 heart failure events (148 with reduced, 150 with preserved, and 59 with unknown ejection fraction). After adjustment for traditional risk factors, the hazard ratio for heart failure per 1 standard deviation higher PTC2 was 0.73 (95% confidence interval: 0.63--0.85). Higher PTC2 was also significantly associated with lower risk of heart failure with reduced ejection fraction (hazard ratio = 0.67; 95% confidence interval: 0.56--0.80). There was no evidence of a significant association between PTC2 and heart failure with preserved ejection fraction or between PTC1 and heart failure.

CONCLUSION

The PTC2 measure of the radial artery pulse waveform may represent a novel phenotype related to heart failure, especially heart failure with reduced ejection fraction.

PTC1 and PTC2: New Indices of Blood Pressure Waveforms and Cardiovascular Disease

Systolic and diastolic blood pressures provide information about cardiovascular disease (CVD) but are only extremes of the pressure waveform during the cardiac cycle. We developed summaries of the pressure decay, called PTC1 and PTC2, that are related to arterial compliance and to an existing proprietary summary that has been shown to predict CVD. We derived the summaries from a Windkessel model (consisting of a decaying exponential plus a dampened cosine, with an intercept so they are independent of calibration with blood pressure, unlike the proprietary measures), and we estimated them using nonlinear least squares with standard, free software. Among 6,228 adults from the Multi-Ethnic Study of Atherosclerosis, initially free of CVD in 2000-2002, mean PTC2 was 94 (standard deviation, 46) milliseconds. During median 15-year follow-up, there were 911 CVD events (including 609 incidents of coronary heart disease and 270 strokes). One-standard-deviation higher PTC2 was associated with 17% (95% confidence interval: 10, 24) lower CVD risk, after adjustment for traditional risk factors. Results were similar for PTC1. PTC1 and PTC2 are relatively straightforward to compute and add information beyond traditional risk factors for prediction of CVD. Our work enables others to replicate and extend our results with waveforms from any suitable device.

Large-Artery Stiffness in Health and Disease: JACC State-of-the-Art Review

A healthy aorta exerts a powerful cushioning function, which limits arterial pulsatility and protects the microvasculature from potentially harmful fluctuations in pressure and blood flow. Large-artery (aortic) stiffening, which occurs with aging and various pathologic states, impairs this cushioning function, and has important consequences on cardiovascular health, including isolated systolic hypertension, excessive penetration of pulsatile energy into the microvasculature of target organs that operate at low vascular resistance, and abnormal ventricular-arterial interactions that promote left ventricular remodeling, dysfunction, and failure. Large-artery stiffness independently predicts cardiovascular risk and represents a high-priority therapeutic target to ameliorate the global burden of cardiovascular disease. This paper provides an overview of key physiologic and biophysical principles related to arterial stiffness, the impact of aortic stiffening on target organs, noninvasive methods for the measurement of arterial stiffness, mechanisms leading to aortic stiffening, therapeutic approaches to reduce it, and clinical applications of arterial stiffness measurements.

The Role of Arterial Stiffness and Central Hemodynamics in Heart Failure

Whereas traditional understanding of left ventricular afterload was focused on a steady-state circulation model with continuous pressures and flow, a more realistic concept is emerging, taking the pulsatile nature of the heart and the arterial system into account. The most simple measure of pulsatility is brachial pulse pressure, representing the pulsatility fluctuating around the mean blood pressure level. Brachial pulse pressure is widely available, fundamentally associated with the development and treatment of heart failure (HF), but its analysis is often confounded in patients with established HF. The next step of analysis consists of arterial stiffness, central (rather than brachial) pressures, and of wave reflections. The latter are closely related to left ventricular late systolic afterload, ventricular remodeling, diastolic dysfunction, exercise capacity, and, in the long term, the risk of new-onset HF. Wave reflection may also evolve as a suitable therapeutic target for HF with preserved and reduced ejection fraction. A full understanding of ventricular-arterial coupling, however, requires dedicated analysis of time-resolved pressure and flow signals. This review provides a summary of current understanding of pulsatile hemodynamics in HF.

Pulsatile arterial haemodynamics in heart failure

Due to the cyclic function of the human heart, pressure and flow in the circulation are pulsatile rather than continuous. Addressing pulsatile haemodynamics starts with the most convenient measurement, brachial pulse pressure, which is widely available, related to development and treatment of heart failure (HF), but often confounded in patients with established HF. The next level of analysis consists of central (rather than brachial) pressures and, more importantly, of wave reflections. The latter are closely related to left ventricular late systolic afterload, ventricular remodelling, diastolic dysfunction, exercise capacity, and, in the long-term, the risk of new-onset HF. Wave reflection may also represent a suitable therapeutic target. Treatments for HF with preserved and reduced ejection fraction, based on a reduction of wave reflection, are emerging. A full understanding of ventricular-arterial coupling, however, requires dedicated analysis of time-resolved pressure and flow signals, which can be readily accomplished with contemporary non-invasive imaging and modelling techniques. This review provides a summary of our current understanding of pulsatile haemodynamics in HF.

A manifesto for cardiovascular imaging: addressing the human factor

Our use of modern cardiovascular imaging tools has not kept pace with their technological development. Diagnostic errors are common but seldom investigated systematically. Rather than more impressive pictures, our main goal should be more precise tests of function which we select because their appropriate use has therapeutic implications which in turn have a beneficial impact on morbidity or mortality. We should practise analytical thinking, use checklists to avoid diagnostic pitfalls, and apply strategies that will reduce biases and avoid overdiagnosis. We should develop normative databases, so that we can apply diagnostic algorithms that take account of variations with age and risk factors and that allow us to calculate pre-test probability and report the post-test probability of disease. We should report the imprecision of a test, or its confidence limits, so that reference change values can be considered in daily clinical practice. We should develop decision support tools to improve the quality and interpretation of diagnostic imaging, so that we choose the single best test irrespective of modality. New imaging tools should be evaluated rigorously, so that their diagnostic performance is established before they are widely disseminated; this should be a shared responsibility of manufacturers with clinicians, leading to cost-effective implementation. Trials should evaluate diagnostic strategies against independent reference criteria. We should exploit advances in machine learning to analyse digital data sets and identify those features that best predict prognosis or responses to treatment. Addressing these human factors will reap benefit for patients, while technological advances continue unpredictably.

Plasma Level of Retinol-Binding Protein 4, N-Terminal proBNP and Renal Function in Older Patients Hospitalized for Heart Failure

BACKGROUND/AIM

Elevated plasma concentration of retinol-binding protein 4 (RBP4) has recently emerged as a potential new risk factor for cardiovascular diseases, including hypertension (HT) and coronary artery disease (CAD). Limited data suggest that RBP4 promotes inflammatory damage to cardiomyocytes and participates in the development of heart failure (HF). This study aimed to analyze the relationship between concentrations of plasma RBP4 and serum N-terminal proBNP (NT-proBNP), a powerful biomarker of left ventricle dysfunction, in the older Polish population.

METHODS

The study sample consisted of 2,826 (1,487 men) participants of the PolSenior study, aged 65 years and older, including a subgroup hospitalized for HF (n = 282). In all subjects, plasma concentrations of RBP4, interleukin-6 (IL-6), serum level of NT-proBNP, and hs-CRP were measured. Additionally, BMI, estimated glomerular filtration rate (eGFR), and HOMA-IR were calculated. The prevalence of HT, CAD, atrial fibrillation (AF), and medication were considered as potential confounders.

RESULTS

Similar RBP4 levels were found in subjects with NT-proBNP < 125 and ≥125 ng/mL, with and without AF, and in the subgroups hospitalized for HF with and without AF. Regression analysis revealed no association between log10(NT-proBNP) and log10(RBP4). Plasma levels of RBP4 were increased by HT occurrence and diuretic therapy, while diminished with regard to female gender, age, eGFR values, AF, and IL-6 levels.

CONCLUSION

Our results show that RBP4 is affected by GFR but cannot be considered as an independent biomarker of heart muscle dysfunction.

Effect of CPAP, Weight Loss, or CPAP Plus Weight Loss on Central Hemodynamics and Arterial Stiffness

Obesity and obstructive sleep apnea tend to coexist. Little is known about the effects of obstructive sleep apnea, obesity, or their treatment on central aortic pressures and large artery stiffness. We randomized 139 adults with obesity (body mass index >30 kg/m2) and moderate-to-severe obstructive sleep apnea to (1) continuous positive airway pressure (CPAP) therapy (n=45), (2) weight loss (WL) therapy (n=48), or (3) combined CPAP and WL (n=46) for 24 weeks. We assessed the effect of these interventions on central pressures and carotid-femoral pulse wave velocity (a measure of large artery stiffness), measured with arterial tonometry. Central systolic pressure was reduced significantly only in the combination arm (-7.4 mm Hg; 95% confidence interval, -12.5 to -2.4 mm Hg; P=0.004), without significant reductions detected in either the WL-only (-2.3 mm Hg; 95% confidence interval, -7.5 to 3.0; P=0.39) or the CPAP-only (-3.1 mm Hg; 95% confidence interval, -8.3 to 2.0; P=0.23) arms. However, none of these interventions significantly changed central pulse pressure, pulse pressure amplification, or the central augmentation index. The change in mean arterial pressure (P=0.008) and heart rate (P=0.027) induced by the interventions was significant predictors of the change in carotid-femoral pulse wave velocity. However, after adjustment for mean arterial pressure and heart rate, no significant changes in carotid-femoral pulse wave velocity were observed in any group. In obese subjects with obstructive sleep apnea, combination therapy with WL and CPAP is effective in reducing central systolic pressure. However, this effect is largely mediated by changes in mean, rather than central pulse pressure. WL and CPAP, alone or in combination, did not reduce large artery stiffness in this population.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00371293.

Sex differences in associations of cardio-ankle vascular index with left ventricular function and geometry

The cardio-ankle vascular index (CAVI) is a measure of global arterial stiffness. We hypothesized that CAVI is associated with left ventricular (LV) function and geometry in individuals without structural heart disease. We measured CAVI in 600 participants (mean age 60.3±14.6 years, 54% men) without history of atherosclerotic cardiovascular disease who were referred for transthoracic echocardiography. Linear regression analysis was used to assess the association of CAVI with LV function (peak mitral annular systolic s' and early diastolic velocity e') and structure (LV mass index (LVMI) and relative wall thickness (RWT)). Older age, male sex, lower body mass index, history of hypertension, diabetes and chronic kidney disease were each associated with a higher CAVI (adjusted R² = 0.56, all p < 0.01). A higher CAVI was associated with lower s' and e', and greater RWT, independent of age, sex, systolic BP and other conventional cardiovascular risk factors (all p < 0.05); a borderline association of higher CAVI with greater LVMI ( p = 0.05) was present. Associations with e', s' and RWT were similar in women and men but the association with LVMI was stronger in women than in men ( p for interaction = 0.02, multivariable-adjusted β = 6.92, p < 0.001 in women; p > 0.1 in men). In conclusion, a higher CAVI, a measure of global arterial stiffness, is associated with worse LV systolic function, worse diastolic relaxation, and greater LV RWT in both men and women, and with LVMI in women.

Deep Phenotyping of Systemic Arterial Hemodynamics in HFpEF (Part 2): Clinical and Therapeutic Considerations

Multiple phase III trials over the last few decades have failed to demonstrate a clear benefit of various pharmacologic interventions in heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF). Therefore, a better understanding of its pathophysiology is important. An accompanying review describes key technical and physiologic aspects regarding the deep phenotyping of arterial hemodynamics in HFpEF. This review deals with the potential of this approach to enhance our clinical, translational, and therapeutic approach to HFpEF. Specifically, the role of arterial hemodynamics is discussed in relation to (1) the pathophysiology of left ventricular diastolic dysfunction, remodeling, and fibrosis, (2) impaired oxygen delivery to peripheral skeletal muscle, which affects peripheral oxygen extraction, (3) the frequent presence of comorbidities, such as renal failure and dementia in this population, and (4) the potential to enhance precision medicine approaches. A therapeutic approach to target arterial hemodynamic abnormalities that are prevalent in this population (particularly, with inorganic nitrate/nitrite) is also discussed.

Deep Phenotyping of Systemic Arterial Hemodynamics in HFpEF (Part 1): Physiologic and Technical Considerations

A better understanding of the pathophysiology of heart failure with a preserved left ventricular ejection fraction (HFpEF) is important. Detailed phenotyping of pulsatile hemodynamics has provided important insights into the pathophysiology of left ventricular remodeling and fibrosis, diastolic dysfunction, microvascular disease, and impaired oxygen delivery to peripheral skeletal muscle, all of which contribute to exercise intolerance, the cardinal feature of HFpEF. Furthermore, arterial pulsatile hemodynamic mechanisms likely contribute to the frequent presence of comorbidities, such as renal failure and dementia, in this population. Our therapeutic approach to HFpEF can be enhanced by clinical phenotyping tools with the potential to "segment" this population into relevant pathophysiologic categories or to identify individuals exhibiting prominent specific abnormalities that can be targeted by pharmacologic interventions. This review describes relevant technical and physiologic aspects regarding the deep phenotyping of arterial hemodynamics in HFpEF. In an accompanying review, the potential of this approach to enhance our clinical and therapeutic approach to HFpEF is discussed.

Central Systolic Hypertension in Patients with Well-Controlled Hypertension

Background. Central systolic blood pressure (CSBP) has prognostic significance and simplified devices for its estimation have been introduced recently. The aim of this study was to assess the achievement of the target CSBP in treated hypertensive patients. Subjects and Methods. One hundred patients with well-controlled hypertension were analysed. For CSBP estimation, we used the Arteriograph (TensioMed Ltd.), which uses one cuff for all measurements, the “single-point measurement” approach. Results. We found that 62% of patients had CSBP ≥ 130 mmHg, the suggested cut-off value for hypertension. When sex-specific classification was employed (CSBP ≥ 137 mmHg for female and CSBP ≥ 133 mmHg for male), only 13% of patients (mainly women) remained in the hypertensive range. We also found that 55% of patients had a CSBP higher than brachial pressure. Multiple analyses showed that CSBP was significantly associated with sex, height, and return time. Conclusions. A high proportion of treated hypertensive patients had CSBP levels that exceeded their brachial BP. CSBP positively correlated with lower height and shorter return time of the reflected pressure wave and was significantly higher in females compared to males. These findings suggest that, for CSBP classification, it is important to take height and sex-specific differences into account.

Ventricular-Arterial Coupling in Chronic Heart Failure

Measures of interaction between the left ventricle (LV) and arterial system (ventricular-arterial coupling) are important but under-recognised cardiovascular phenotypes in heart failure. Ventriculo-arterial coupling is commonly assessed in the pressure-volume plane, using the ratio of effective arterial elastance (E_A) to LV end-systolic elastance (E_ES) to provide information on ventricular-arterial system mechanical efficiency and performance when LV ejection fraction is abnormal. These analyses have significant limitations, such as neglecting systolic loading sequence, and are less informative in heart failure with preserved ejection fraction (HFpEF). E_A is almost entirely dependent on vascular resistance and heart rate. Assessment of pulsatile arterial haemodynamics and time-resolved myocardial wall stress provide critical incremental physiological information and should be more widely utilised. Pulsatile arterial load represents a promising therapeutic target in HFpEF. Here, we review various approaches to assess ventricular-arterial interactions, and their pathophysiological and clinical implications in heart failure.

Pulsatile Load Components, Resistive Load and Incident Heart Failure: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Left ventricular (LV) afterload is composed of systemic vascular resistance (SVR) and components of pulsatile load, including total arterial compliance (TAC), and reflection magnitude (RM). RM, which affects the LV systolic loading sequence, has been shown to strongly predict HF. Effective arterial elastance (E_a) is a commonly used parameter initially proposed to be a lumped index of resistive and pulsatile afterload. We sought to assess how various LV afterload parameters predict heart failure (HF) risk and whether RM predicts HF independently from subclinical atherosclerosis.

METHODS

We studied 4345 MESA participants who underwent radial arterial tonometry and cardiac output (CO) measurements with the use of cardiac MRI. RM was computed as the ratio of the backward (P_b) to forward (P_f) waves. TAC was approximated as the ratio of stroke volume (SV) to central pulse pressure. SVR was computed as mean pressure/CO. E_a was computed as central end-systolic pressure/SV.

RESULTS

During 10.3 years of follow-up, 91 definite HF events occurred. SVR (P = .74), TAC (P = .81), and E_a (P = .81) were not predictive of HF risk. RM was associated with increased HF risk, even after adjustment for other parameters of arterial load, various confounders, and markers of subclinical atherosclerosis (standardized hazard ratio [HR] 1.49, 95% confidence interval [CI] 1.18-1.88; P = .001). P_b was also associated with an increased risk of HF after adjustment for P_f (standardized HR 1.43, 95% CI 1.17-1.75; P = .001).

CONCLUSIONS

RM is an important independent predictor of HF risk, whereas TAC, SVR, and E_a are not. Our findings support the importance of the systolic LV loading sequence on HF risk, independently from subclinical atherosclerosis.

Novel Uses of Office-Based Measures of Arterial Compliance

Office-based blood pressure monitoring has been the primary way of managing the cardiovascular risk associated with a diagnosis of hypertension. As research unfolds the nature in which the pulse waveform is generated, additional insights beyond standard measures of systolic and diastolic blood pressure have emerged to help reclassify the cardiovascular risk of patients or point out patterns that have, in longitudinal cohort studies, shown promise as predictors of outcomes such as heart failure. In this review, we focus on the pressure profile in the proximal aorta that can be obtained easily and noninvasively from the radial or brachial artery during a clinical office encounter and the potential value of these measures in outcomes such as left ventricular hypertrophy and heart failure.

American Society of Hypertension position paper: central blood pressure waveforms in health and disease

A number of devices are available which noninvasively estimate central aortic blood pressure using a variety of approaches such as tonometry or oscillometry. In this position paper, we discuss how the central pressure waveform is generated and measured, how central pressure waveforms appear in health and disease, the predictive value of central blood pressure measurements, the effects of interventions on waveforms, and areas of future need in this field of clinical and research endeavor.

A histopathological analysis of the epidemiology of coronary atherosclerosis: an autopsy study

BACKGROUND

Atherosclerosis accounts for a large proportion of cardiovascular system associated morbidity and mortality. We studied the possible association between the histopathological changes of the coronary atherosclerotic lesions and the risk of sudden cardiac death (SCD) using autopsy cases.

METHODS

We performed an autopsy analysis (n = 13, 4 women, 9 men mean age 67.5 years; age range 56-93 years) of SCD which occurred in patients aged over 50 years during March 2010 to December 2013. The following variables were considered: sex, age, medical history, autopsy findings to macroscopic and histological evaluation of the heart. The autopsies were performed according to standard techniques. In all subjects, the heart was dissected following standard autopsy protocol and a 5 cm section of the right coronary artery (RCA) in the atrio-ventricular groove from its origin, a 5 cm segment of the left anterior descending artery (LADA) distal to the origin of the circumflex artery, but including the region of origin of the circumflex branch and left coronary artery (LCA) from its origin till the circumflex branch were excised, dissected out, fixed in 10% formalin, marked for identification and sent for histopathological analysis.

RESULTS

Atherosclerotic plaques were identified in 6.5% of specimens, 69.34% of males and 30.66% of female. Such plaques were typically concentric and more represented with necrosis, calcification, cholesterol crystals, and giant cells, as well as had a higher inflammatory cell count. Furthermore, intima and media thickness of coronary arteries were significantly higher in studied specimens with visualize the connective tissue layers of the adventitia and the fatty acid containing adipose cells in the periadventitial tissue. Furthermore, the degree of microscopic lesion of atherosclerosis increased proportionally with the increase in the intensity of lipid deposition and with the percentage of collagen in the atherosclerotic plaques.

CONCLUSION

In this study, age estimate to be a risk factor for coronary atherosclerosis in individuals more than 50 years old and may be used to predict SCD. Altogether, an enhanced understanding of the pathobiologic processes responsible for atherosclerotic changes might allow for early identification of a high-risk coronary plaque and thereby provide a rationale for innovative diagnostic and/or therapeutic strategies for the management of coronary patients and prevention of acute coronary syndromes.