Age- and gender-related ventricular-vascular stiffening: a community-based study

Hemodynamic function of the right ventricular-pulmonary vascular-left atrial unit: normal responses to exercise in healthy adults

With each heartbeat, the right ventricle (RV) inputs blood into the pulmonary vascular (PV) compartment, which conducts blood through the lungs at low pressure and concurrently fills the left atrium (LA) for output to the systemic circulation. This overall hemodynamic function of the integrated RV-PV-LA unit is determined by complex interactions between the components that vary over the cardiac cycle but are often assessed in terms of mean pressure and flow. Exercise challenges these hemodynamic interactions as cardiac filling increases, stroke volume augments, and cycle length decreases, with PV pressures ultimately increasing in association with cardiac output. Recent cardiopulmonary exercise hemodynamic studies have enriched the available data from healthy adults, yielded insight into the underlying mechanisms that modify the PV pressure-flow relationship, and better delineated the normal limits of healthy responses to exercise. This review will examine hemodynamic function of the RV-PV-LA unit using the two-element Windkessel model for the pulmonary circulation. It will focus on acute PV and LA responses that accommodate increased RV output during exercise, including PV recruitment and distension and LA reservoir expansion, and the integrated mean pressure-flow response to exercise in healthy adults. Finally, it will consider how these responses may be impacted by age-related remodeling and modified by sex-related cardiopulmonary differences. Studying the determinants and recognizing the normal limits of PV pressure-flow relations during exercise will improve our understanding of cardiopulmonary mechanisms that facilitate or limit exercise.

Sex Differences in Cardiovascular Aging and Heart Failure

PURPOSE OF THE REVIEW

This review summarizes sex-related changes in the heart and vasculature that occur with aging, both in the presence and absence of cardiovascular disease (CVD).

RECENT FINDINGS

In the presence of CVD risk factors and/or overt CVD, sex-specific changes in the number of cardiomyocytes, extent of the myocardial extracellular matrix, and myocellular hypertrophy promote unique patterns of LV remodeling in men and women. In addition, age- and sex-specific vascular stiffening is also well established, driven by changes in endothelial dysfunction, elastin-collagen content, microvascular dysfunction, and neurohormonal signaling. Together, these changes in LV chamber geometry and morphology, coupled with heightened vascular stiffness, appear to drive both age-related increases in systolic function and declines in diastolic function, particularly in postmenopausal women. Accordingly, estrogen has been implicated as a key mediator, given its direct vasodilating properties, association with nitric oxide excretion, and involvement in myocellular Ca2+ handling, mitochondrial energy production, and oxidative stress. The culmination of the abovementioned sex-specific cardiac and vascular changes across the lifespan provides important insight into heart failure development, particularly of the preserved ejection fraction variety, while offering promise for future preventive strategies and therapeutic approaches.

Sex-specific cardiac and vascular responses to hypertension in Chinese populations without overt cardiovascular diseases

OBJECTIVE

The aim of current study was to evaluate sex-specific cardiac and vascular responses to hypertension in Chinese populations without overt cardiovascular disease.

METHODS

This was a cross-sectional study and participants were enrolled in outpatient clinic between January 2017 and December 2019. Transthoracic echocardiographic measurements were performed to evaluate cardiac and vascular structure and function.

RESULTS

Among 486 participants, women account for 36.2% (n = 176). Compared to men, women were younger, had shorter duration of hypertension, and more likely to be abdominal obesity. Mean systolic and diastolic blood pressure (SBP and DBP) were similar, but women had higher mean pulse pressure (PP) than men. After adjustment for covariates, women had higher E/e' ratio and arterial elastance (Ea). The proportion of patients with concentric remodeling was higher in women (14.7% vs 9.5%). Increased SBP was associated with relative wall thickness (RWT), stroke volume (SV) index, E/e' ratio and Ea in both women and men, and the magnitude of the association between SBP and E/e' ratio was greater in women than in men (P_interaction = 0.04). Increased DBP was associated with RWT and Ea in both women and men with similar magnitude. Increased PP was associated with RWT, E/e' ratio and Ea in both women and men, and the magnitude of the association between PP and Ea was greater in women than in men (P_interaction = 0.03).

CONCLUSION

In conclusion, the current study indicates cardiac and vascular responses to hypertension are greater in women than in men, manifesting as an increased estimated LV filling pressure and arterial elastance in women.

Determinants of LA reservoir strain: Independent effects of LA volume and LV global longitudinal strain

BACKGROUND

Left atrial (LA) deformation during the reservoir phase (LASr) has demonstrated strong prognostic value in different clinical settings. Although determinants of left atrial reservoir strain including left atrial relaxation, left atrial compliance, and left ventricular longitudinal systolic function are fairly well defined, there is incomplete information regarding the effect of left atrial volume on this relationship which is the focus of our study.

METHOD

Consecutive patients without prior cardiac disease referred for transthoracic echocardiography were prospectively recruited. All participants underwent clinical assessment, transthoracic echocardiography (TTE), and screening exercise stress test. Only patients with normal left ventricular ejection fraction (LVEF) without left ventricular hypertrophy (LVH) or myocardial ischemia on stress testing were included.

RESULTS

A total of 260 patients (57% male, mean age 59 ± 14 years) were included. 70% had hypertension, 33% had diabetes mellitus, and 31% had both HTN and DM. On multivariate analysis, age, e', LAVI, and LV GLS (P < .01 for all) showed an independent association with LASr. Of interest, at lower tertiles of LAVI, a linear decrease in LASr was observed parallel to worsening LV GLS, whilst at higher tertiles of LAVI, the reduction in LASr was non-linear implying that LA enlargement, consequent to LA remodeling, had an incremental effect on LASr.

CONCLUSION

Age, e', LV GLS, and LAVI were independently associated with LASr. LA remodeling reflected by larger LAVI had an incremental negative association with LASr independent of LV GLS.

Usefulness of left atrial strain for predicting incident atrial fibrillation and ischaemic stroke in the general population

AIMS

Left atrial enlargement predicts incident atrial fibrillation (AF). However, the prognostic value of peak atrial longitudinal strain (PALS) for predicting incident AF in participants from the general population is currently unknown. Our aim was to investigate if PALS can be used to predict AF and ischaemic stroke in the general population.

METHODS AND RESULTS

A total of 400 participants from the general population underwent a health examination, including two-dimensional speckle tracking echocardiography of the left atrium. The primary endpoint was incident AF at follow-up. All participants with known AF and prior stroke at baseline were excluded (n = 54). The secondary endpoint consisted of the composite of AF and ischaemic stroke. During a median follow-up of 16 years, 36 participants (9%) were diagnosed with incident AF and 30 (7%) experienced an ischaemic stroke, resulting in 66 (16%) experiencing the composite outcome. PALS was a univariable predictor of AF [per 5% decrease: hazard ratio (HR) 1.42; 95% confidence interval (CI) (1.19-1.69), P < 0.001]. However, the prognostic value of PALS was modified by age (P = 0.002 for interaction). After multivariable adjustment PALS predicted AF in participants aged <65 years [per 5% decrease: HR 1.46; 95% CI (1.06-2.02), P = 0.021]. In contrast, PALS did not predict AF in participants aged ≥65 years after multivariable adjustment [per 5% decrease: HR 1.05; 95% CI (0.81-1.35), P = 0.72]. PALS also predicted the secondary endpoint in participants aged <65 years and the association remained significant after multivariable adjustment.

CONCLUSION

In a low-risk general population, PALS provides novel prognostic information on the long-term risk of AF and ischaemic stroke in participants aged <65 years.

Topoisomerase 2B Decrease Results in Diastolic Dysfunction via p53 and Akt: A Novel Pathway

Diastolic dysfunction is condition of a stiff ventricle and a function of aging. It causes significant cardiovascular mortality and morbidity, and in fact, three million Americans are currently suffering from this condition. To date, all the pharmacological clinical trials have been negative. The lack of success in attenuating/ameliorating diastolic dysfunction stems from lack of duplication of myriads of clinical manifestation in pre-clinical settings. Here we report, a novel genetically engineered mice which may represents a preclinical model of human diastolic dysfunction to some extent. Topoisomerase 2 beta (Top2b) is an important enzyme in transcriptional activation of some inducible genes through transient double-stranded DNA breakage events around promoter regions. We created a conditional, tissue-specific, inducible Top2b knockout mice in the heart. Serendipitously, echocardiographic parameters and more invasive analysis of left ventricular function with pressure–volume loops show features of diastolic dysfunction. This was also confirmed histologically. At the cellular level, the Top2b knockdown showed morphological changes and molecular signaling akin to human diastolic dysfunction. Reverse phase protein analysis showed activation of p53 and inhibition of, Akt, as the possible mediators of diastolic dysfunction. Finally, activation of p53 and inhibition of Akt were confirmed in myocardial biopsy samples obtained from human diastolic dysfunctional hearts. Thus, we report for the first time, a Top2b downregulated preclinical mice model for diastolic dysfunction which demonstrates that Akt and p53 are the possible mediators of the pathology, hence representing novel and viable targets for future therapeutic interventions in diastolic dysfunction.

Are there gender differences in the association between body mass index and left ventricular diastolic function? A clinical observational study in the Japanese general population

BACKGROUND

Increased body mass index (BMI) is a major risk factor for heart failure with preserved ejection fraction (HFpEF), and HFpEF is more prevalent in elderly females than males. We hypothesized that there may be gender differences in the association between BMI and echocardiographic left ventricular (LV) diastolic parameters.

METHODS

We enrolled 456 subjects (243 males) without overt cardiac diseases, all of whom underwent a health checkup. Early (E) and late (A) diastolic transmitral flow velocity, early diastolic mitral annular velocity (e'), and left atrial (LA) volume index were measured by echocardiography to assess LV diastolic function. To examine gender differences in the association between BMI and LV diastolic function, we analyzed the interaction effects of gender on the association between BMI and echocardiographic LV diastolic parameters.

RESULTS

Although there were significant gender differences in the association between BMI and E/A and e' in the crude model (interaction effect 0.037 and 0.173, respectively; P = .006 and .022, respectively), these differences were not statistically significant after adjustment for factors related to LV diastolic function. On the other hand, there were significant associations between BMI and LV diastolic parameters in each gender, even after adjustment.

CONCLUSIONS

Our findings suggest there is no gender difference in the association between BMI and echocardiographic LV diastolic parameters. However, the association between BMI and LV diastolic parameters was significant in both genders. Controlling body weight might be beneficial for both women and men to prevent progression of LV diastolic dysfunction and development of HFpEF.

Sex-Specific Associations of Cardiovascular Risk Factors and Biomarkers With Incident Heart Failure

BACKGROUND

Whether cardiovascular (CV) disease risk factors and biomarkers associate differentially with heart failure (HF) risk in men and women is unclear.

OBJECTIVES

The purpose of this study was to evaluate sex-specific associations of CV risk factors and biomarkers with incident HF.

METHODS

The analysis was performed using data from 4 community-based cohorts with 12.5 years of follow-up. Participants (recruited between 1989 and 2002) were free of HF at baseline. Biomarker measurements included natriuretic peptides, cardiac troponins, plasminogen activator inhibitor-1, D-dimer, fibrinogen, C-reactive protein, sST2, galectin-3, cystatin-C, and urinary albumin-to-creatinine ratio.

RESULTS

Among 22,756 participants (mean age 60 ± 13 years, 53% women), HF occurred in 2,095 participants (47% women). Age, smoking, type 2 diabetes mellitus, hypertension, body mass index, atrial fibrillation, myocardial infarction, left ventricular hypertrophy, and left bundle branch block were strongly associated with HF in both sexes (p < 0.001), and the combined clinical model had good discrimination in men (C-statistic = 0.80) and in women (C-statistic = 0.83). The majority of biomarkers were strongly and similarly associated with HF in both sexes. The clinical model improved modestly after adding natriuretic peptides in men (ΔC-statistic = 0.006; likelihood ratio chi-square = 146; p < 0.001), and after adding cardiac troponins in women (ΔC-statistic = 0.003; likelihood ratio chi-square = 73; p < 0.001).

CONCLUSIONS

CV risk factors are strongly and similarly associated with incident HF in both sexes, highlighting the similar importance of risk factor control in reducing HF risk in the community. There are subtle sex-related differences in the predictive value of individual biomarkers, but the overall improvement in HF risk estimation when included in a clinical HF risk prediction model is limited in both sexes.

Aortic Root Remodeling as an Indicator for Diastolic Dysfunction and Normative Ranges in Asians: Comparison and Validation with Multidetector Computed Tomography

Background: The aortic root diameter (AoD) has been shown to be a marker of cardiovascular risk and heart failure (HF). Data regarding the normal reference ranges in Asians and their correlates with diastolic dysfunction using contemporary guidelines remain largely unexplored. Methods: Among 5343 consecutive population-based asymptomatic Asians with echocardiography evaluations for aortic root diameter (without/with indexing, presented as AoD/AoDi) were related to cardiac structure/function and N-terminal pro-brain B-type natriuretic peptide (Nt-ProBNP), with 245 participants compared with multidetector computed tomography (MDCT)-based aortic root geometry. Results: Advanced age, hypertension, higher diastolic blood pressure, and lower body fat all contributed to greater AoD/AoDi. The highest correlation between echo-based aortic diameter and the MDCT-derived measures was found at the level of the aortic sinuses of Valsalva (r = 0.80, p < 0.001). Age- and sex-stratified normative ranges of AoD/AoDi were provided in 3646 healthy participants. Multivariate linear regressions showed that AoDi was associated with a higher NT-proBNP, more unfavorable left ventricular (LV) remodeling, worsened LV systolic annular velocity (TDI-s′), a higher probability of presenting with LV hypertrophy, and abnormal LV diastolic indices except tricuspid regurgitation velocity by contemporary diastolic dysfunction (DD) criteria (all p < 0.05). AoDi superimposed on key clinical variables significantly expanded C-statistic from 0.71 to 0.84 (p for ∆AUROC: < 0.001). These associations were broadly weaker for AoD. Conclusion: In our large asymptomatic Asian population, echocardiography-defined aortic root dilation was associated with aging and hypertension and were correlated modestly with computed tomography measures. A larger indexed aortic diameter appeared to be a useful indicator in identifying baseline abnormal diastolic dysfunction.

Physiological variations of blood pressure according to gender and age among healthy young black Africans aged between 18 and 30 years in Côte d'Ivoire, West Africa

In Africa, abnormal high blood pressure is common and affects young subjects. The risk of organ damage and mortality increases with blood pressure level. Therefore, the purpose of this study was to assess the blood pressure profile of a black African population aged between 18 and 30 years in Côte d'Ivoire. Five hundred fifty-one healthy black African students, men and women, with sedentary lifestyle, aged between 18 and 30 years were selected. Systolic (SBP) and diastolic (DBP) blood pressures and heart rate were recorded after 5 min of rest. Regression models were used to estimate the effects of age, gender, and body mass index (BMI) on SBP and DBP. Each increase of 1 year in age and 1 kg/m2 of BMI is significantly associated, respectively, with an increase of 20% (p = .002) and 17% (p = .008) in the risk of having an SBP ≥ 130 mmHg. The same risk is 3.8 times greater for men than women (p = .01). Among subjects with SBP < 120 mmHg, men have an SBP 5.22 mmHg higher than women (p < .001). The increase in the age of 1 year is significantly correlated with a rise of 36% of having a DBP ≥ 85 mmHg (p = .0001). Also, in men population, the age increase of 1 year is associated with a rise of 41% of having a DBP ≥ 85 mmHg (p = .0001). Among young black African students aged between 18 and 30 years in Côte d'Ivoire, SBP is positively associated with male gender, age, and BMI. For DBP, it is only an increase with age.

Arterial stiffening is a crucial factor for left ventricular diastolic dysfunction in a community-based normotensive population

BACKGROUND

Left ventricular (LV) diastolic dysfunction is an important underlying hemodynamic mechanism for heart failure. Hypertension reportedly increases aortic stiffness with histological changes in the aorta assessed using aortic pulse wave velocity (PWV) that is associated with LV diastolic dysfunction. The role of hypertension per se in the relationship between aortic stiffness and LV diastolic dysfunction has not been clarified; therefore, we investigated whether this relation works for normotensive subjects.

METHODS

Of the 502 subjects who underwent both echocardiography and PWV measurement in a medical check-up conducted in Arita, Japan, we enrolled 262 consecutive normotensive subjects (age 52 ± 13 years). LV diastolic dysfunction was defined as abnormal relaxation and pseudonormal or restrictive patterns determined with both transmitral flow velocity and mitral annular velocity. Aortic stiffness was assessed via non-invasive brachial-ankle PWV measurement.

RESULTS

LV diastolic dysfunction was detected in 67 of the 262 (26%) normotensive subjects, and PWV was higher in subjects with LV diastolic dysfunction (15.4 ± 3.6 vs. 13.0 ± 2.7 m/s, p < 0.01). Multivariate logistic regression analyses revealed that PWV was independently associated with LV diastolic dysfunction (p = 0.02) after the adjustment for age; body mass index; blood pressure; eGFR; blood levels of BNP, glucose, and HDL cholesterol; LV mass index; and LA dimension.

CONCLUSIONS

Both aortic stiffness and LV diastolic function are mutually related even in normotensive subjects, independent of the potential confounding factors. The increase in aortic stiffness may be a risk factor for LV diastolic dysfunction, irrespective of blood pressure.

Echocardiographic predictors of cardiovascular morbidity and mortality in women from the general population

AIMS

Global longitudinal strain (GLS) is a strong predictor of adverse cardiovascular outcome in men. However, studies have indicated that GLS may not predict cardiovascular outcomes as effectively in women. The aim of this study was to identify echocardiographic predictors of cardiovascular morbidity and mortality in women from the general population.

METHODS AND RESULTS

A total of 1245 women from the general population free of heart failure (HF) and atrial fibrillation had an echocardiographic examination performed including tissue Doppler imaging. In this subset, 747 women had images eligible for strain analysis. Endpoint was a composite of acute myocardial infarction, HF, and cardiovascular death. During follow-up (median 12.5 years), 162 women (13.0%) reached the composite outcome. These women had higher left ventricular (LV) mass index (LVMI), more LV hypertrophy, lower E/A, higher E/e', larger LV dimensions, and longer deceleration time. LVMI and e' remained as significant predictors of the composite outcome [LVMI: hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.03-1.17, P = 0.004, per 5 g/m2 increase] (e': HR 1.53, 95% CI 1.07-2.20, P = 0.020, per 1 cm/s decrease) after adjusting for age, hypertension, systolic blood pressure, diabetes mellitus, total cholesterol, smoking status, prevalent ischaemic heart disease, LV ejection fraction, E/e', E, E/A, interventricular septum thickness in diastole, left ventricular posterior wall in diastole, a', body surface area, and pro-brain natriuretic peptide. GLS was not an independent predictor of outcome after multivariable adjustment.

CONCLUSION

The degree of LV hypertrophy assessed as LVMI and diastolic dysfunction evaluated by e' are associated with adverse cardiovascular outcome in women from the general population.

Is the healthy respiratory system built just right, overbuilt, or underbuilt to meet the demands imposed by exercise?

In the healthy, untrained young adult, a case is made for a respiratory system (airways, pulmonary vasculature, lung parenchyma, respiratory muscles, and neural ventilatory control system) that is near ideally designed to ensure a highly efficient, homeostatic response to exercise of varying intensities and durations. Our aim was then to consider circumstances in which the intra/extrathoracic airways, pulmonary vasculature, respiratory muscles, and/or blood-gas distribution are underbuilt or inadequately regulated relative to the demands imposed by the cardiovascular system. In these instances, the respiratory system presents a significant limitation to O₂ transport and contributes to the occurrence of locomotor muscle fatigue, inhibition of central locomotor output, and exercise performance. Most prominent in these examples of an "underbuilt" respiratory system are highly trained endurance athletes, with additional influences of sex, aging, hypoxic environments, and the highly inbred equine. We summarize by evaluating the relative influences of these respiratory system limitations on exercise performance and their impact on pathophysiology and provide recommendations for future investigation.

Carotid arterial stiffness is increased and related to left ventricular function in patients with hypertrophic cardiomyopathy

Aims

To assess the carotid mechanical properties in patients with hypertrophic cardiomyopathy and the relation between arterial stiffness and left ventricular function in this setting.

Methods and results

We have prospectively enrolled 71 patients (52 ± 16 years, 34 men) with hypertrophic cardiomyopathy, divided into two groups depending on the presence (46 patients) or absence (25 patients) of cardiovascular risk factors associated with increased arterial stiffness. Twenty-five normal subjects similar by age and gender with hypertrophic cardiomyopathy patients without risk factors formed the control group. A comprehensive echocardiography was performed in all subjects. Carotid arterial stiffness index (β index), pressure–strain elastic modulus, arterial compliance, and pulse wave velocity were also obtained using an echo-tracking system. β index, pulse wave velocity, and pressure–strain elastic modulus were significantly higher in hypertrophic cardiomyopathy patients without risk factors compared to controls. After linear regression analysis, the increase in carotid β index was independently correlated with the presence of hypertrophic cardiomyopathy [beta = 0.49, 95% confidence interval (CI) = 1.04–3.02; P &lt; 0.001]. In the entire hypertrophic cardiomyopathy population arterial stiffness parameters correlated with age, gender, hypertension degree, presence of hypercholesterolaemia, and the E/e′ ratio. In multivariable analysis, β index (beta = 0.36, 95% CI = 0.32–1.25; P = 0.001), global left ventricular longitudinal strain, and the presence of left ventricular outflow tract obstruction were independently correlated with the E/e′ ratio.

Conclusion

In patients with hypertrophic cardiomyopathy arterial stiffness is increased independently of age or presence of cardiovascular risk factors. Carotid artery stiffness is independently related to left ventricular filling pressure, increased arterial stiffness representing a possible marker of a more severe phenotype.

Sex related differences in the pathogenesis of organ fibrosis

The development of organ fibrosis has garnered rising attention as multiple diseases of increasing and/or high prevalence appear to progress to the chronic stage. Such is the case for heart, kidney, liver, and lung where diseases such as diabetes, idiopathic/autoimmune disorders, and nonalcoholic liver disease appear to notably drive the development of fibrosis. Noteworthy is that the severity of these pathologies is characteristically compounded by aging. For these reasons, research groups and drug companies have identified fibrosis as a therapeutic target for which currently, there are essentially no effective options. Although a limited body of published studies are available, most literature indicates that in multiple organs, premenopausal women are protected from developing severe forms of fibrosis suggesting an important role for sex hormones in mitigating this process. Investigators have implemented relevant animal models of organ disease linked to fibrosis supporting in general, these observations. In vitro studies and transgenic animals models have also been used in an attempt to understand the role that sex hormones and related receptors play in the development of fibrosis. However, in the setting of chronic disease in some organs such as the heart older (postmenopausal) women within a few years can quickly approach men in disease severity and develop significant degrees of fibrosis. This review summarizes the current body of relevant literature and highlights the imperative need for a major focus to be placed on understanding the manner in which sex and the presence or absence of related hormones modulates cell phenotypes so as to allow for fibrosis to develop.

High-Resolution Transcriptomic Profiling of the Heart During Chronic Stress Reveals Cellular Drivers of Cardiac Fibrosis and Hypertrophy

Supplemental Digital Content is available in the text.

Background:

Cardiac fibrosis is a key antecedent to many types of cardiac dysfunction including heart failure. Physiological factors leading to cardiac fibrosis have been recognized for decades. However, the specific cellular and molecular mediators that drive cardiac fibrosis, and the relative effect of disparate cell populations on cardiac fibrosis, remain unclear.

Methods:

We developed a novel cardiac single-cell transcriptomic strategy to characterize the cardiac cellulome, the network of cells that forms the heart. This method was used to profile the cardiac cellular ecosystem in response to 2 weeks of continuous administration of angiotensin II, a profibrotic stimulus that drives pathological cardiac remodeling.

Results:

Our analysis provides a comprehensive map of the cardiac cellular landscape uncovering multiple cell populations that contribute to pathological remodeling of the extracellular matrix of the heart. Two phenotypically distinct fibroblast populations, Fibroblast-Cilp and Fibroblast-Thbs4, emerged after induction of tissue stress to promote fibrosis in the absence of smooth muscle actin–expressing myofibroblasts, a key profibrotic cell population. After angiotensin II treatment, Fibroblast-Cilp develops as the most abundant fibroblast subpopulation and the predominant fibrogenic cell type. Mapping intercellular communication networks within the heart, we identified key intercellular trophic relationships and shifts in cellular communication after angiotensin II treatment that promote the development of a profibrotic cellular microenvironment. Furthermore, the cellular responses to angiotensin II and the relative abundance of fibrogenic cells were sexually dimorphic.

Conclusions:

These results offer a valuable resource for exploring the cardiac cellular landscape in health and after chronic cardiovascular stress. These data provide insights into the cellular and molecular mechanisms that promote pathological remodeling of the mammalian heart, highlighting early transcriptional changes that precede chronic cardiac fibrosis.

Associations of serum uric acid level and gout with cardiac structure, function and sex differences from large scale asymptomatic Asians

Hyperuricemia (HU) is a marker for heart failure. There are relatively few data in the Asian population regarding the effects of hyperuricemia and gouty disorders on cardiac remodeling and diastolic dysfunction (DD), an intermediate stage in the development of heart failure. We consecutively recruited asymptomatic Asian individuals to undergo cardiovascular surveys. We categorized them into Non-HU, HU, and Gout groups. We measured cardiac structure and indices for diastolic function, including tissue Doppler (TDI)-derived LV e’ and E/e’. Among 5525 participants, 1568 had HU and 347 had gout. The presence of gout and higher uric acid levels (SUA) (<4, 4–6, 6–8, 8–10, > = 10 mg/dL) were associated with greater LV wall thickness, greater LV mass/volumes, larger LA volume, lower LV e’ and higher E/e’. Higher SUA was associated with greater LV mass index (adjusted coefficient: 0.37), greater mass/volume ratio (adjusted coefficient: 0.01) and larger LA volume index (adjusted coefficient: 0.39, all p<0.05). Both HU and Gout groups were associated with lower LV e’ (coefficient: -0.086, -0.05), higher E/e’ (coefficient: 0.075, 0.35, all p <0.05), larger LA volume, and higher DD risk (adjusted ORs: 1.21 and 1.91 using Non-HU as reference, respectively, both p <0.05). SUA set at 7.0 mg/dL provided the optimal cut-off for identifying DD, with markedly lower e’ (HU: 8.94 vs 8.07, Gout: 7.94 vs 7.26 cm/sec) and higher LV E/e’ in HU/Gout women than in men (HU: 7.84 vs 9.79 cm/sec for men and women, respectively, all p <0.05). Hyperuricemia, even at a relatively low clinical cut-off, was associated with unfavorable remodeling and was tightly linked to diastolic dysfunction. The presence of gout likely aggravated these conditions. Women with hyperuricemia or gout had worse diastolic indices than men despite similar degrees of LV remodeling.

Ventricular-vascular coupling in heart failure with preserved ejection fraction: A systematic review and meta-analysis

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a complex disease underlined by impaired ventricular-vascular coupling (VVC).

OBJECTIVES

To evaluate the VVC ratio in HFpEF patients at rest and during exercise and compare it to the healthy and heart failure with reduced ejection fraction (HFrEF) controls.

METHODS

PubMed and EMBASE databases were searched for trials that matched the inclusion criteria. Random-effects models were used to estimate the pooled mean difference with 95% confidence interval using Open Meta[Analyst] software.

RESULTS

A total of 13 trials met the inclusion criteria. Although VVC ratio was comparable between HFpEF and healthy controls at rest, it was significantly lower in HFrEF compared to HFpEF. During exercise, there was a significant decline in VVC ratio in HFpEF (-0.119, 95% CI (-0.183 to -0.055), p<0.001).

CONCLUSION

VVC ratio, although 'preserved' at rest in HFpEF patients, was overtly impaired during exercise highlighting the importance of dynamic testing.

Prognostic significance of patent foramen ovale in anticoagulated patients with atrial fibrillation

Objective

Previous studies have postulated a causal role of patent foramen ovale (PFO) in the aetiology of embolic stroke in the general population. We hypothesised that the presence of concomitant PFO and atrial fibrillation (AF) will add incremental risk of ischaemic stroke to that linked to AF alone.

Methods

We analysed data on 3069 consecutive patients (mean age 69.4±12.2 years; 67.1% men) undergoing transoesophageal echocardiography-guided electrical cardioversion (ECV) for AF between May 2000 and March 2012. PFO was identified by colour Doppler and agitated saline contrast study. All patients were followed up after ECV for first documentation of ischaemic stroke. Outcomes were compared using Cox regression models.

Results

The prevalence of PFO was 20.0% and the shunt direction was left-to-right in the majority of patients (71.4%). Patients with PFO had a higher frequency of obstructive sleep apnoea (21.7% vs 17.1%, p=0.01) and higher mean peak left atrial appendage emptying velocity (38.3±21.8 vs 36.1±20.4 cm/s; p=0.04) compared with those without PFO. Otherwise, baseline characteristics were similar between groups. During a mean follow-up period of 7.3±4.6 years, 214 patients (7.0%) had ischaemic stroke. Multivariable analysis showed no significant association between PFO and ischaemic stroke (HR, 0.82 (95% CI 0.57 to 1.18)). PFO shunt direction was strongly associated with stroke: HR, 1.91 (95% CI 1.16 to 3.16) for right-to-left shunt and HR, 0.58 (95% CI 0.36 to 0.93) for left-to-right shunt.

Conclusions

The presence of concurrent PFO in this largely anticoagulated group of patients with AF was not associated with increased risk of ischaemic stroke.

Obesity and cardiovascular disease in women

As the prevalence of obesity continues to grow worldwide, the health and financial burden of obesity-related comorbidities grows too. Cardiovascular disease (CVD) is clearly associated with increased adiposity. Importantly, women are at higher risk of CVD when obese and insulin resistant, in particular at higher risk of developing heart failure with preserved ejection fraction and ischemic heart disease. Increased aldosterone and mineralocorticoid receptor activation, aberrant estrogenic signaling and elevated levels of androgens are among some of the proposed mechanisms explaining the heightened CVD risk. In addition to traditional cardiovascular risk factors, understanding nontraditional risk factors specific to women, like excess weight gain during pregnancy, preeclampsia, gestational diabetes, and menopause are central to designing personalized interventions aimed to curb the epidemic of CVD. In the present review, we examine the available evidence supporting a differential cardiovascular impact of increased adiposity in women compared with men and the proposed pathophysiological mechanisms behind these differences. We also discuss women-specific cardiovascular risk factors associated with obesity and insulin resistance.

Carotid arterial mechanics as useful biomarker of extracellular matrix turnover and preserved ejection fraction heart failure

Aims

We aimed to investigate the functional alterations, diagnostic utilization, and prognostic implication of carotid arterial deformations in subjects with cardiovascular risk factors and heart failure (HF) with preserved ejection fraction (HFpEF).

Methods and results

Among 251 prospectively participants (mean age 66.0 ± 9.8 years, 65.7% female) in a single centre between December 2011 and September 2014, carotid artery deformations including circumferential strain (CCS)/strain rate and radial strain were analysed by two‐dimensional speckle tracking. We further related these carotid artery deformation indices to HF biomarkers and cardiac structure and function by echocardiography and explored their prognostic values. Significant reductions of CCS, circumferential strain rate, and circumferential radial strain were observed across control (n = 52), high risk (n = 147), and HFpEF (n = 52) (trend P ≤ 0.001). Aging, hypertension, HFpEF, and higher pulse rate showed independent associations with reduced CCS by stepwise multivariate regressions (all P < 0.05). Higher CCS was inversely associated with better cardiac remodelling and functional indices, and lower multiple HF biomarkers (all P ≤ 0.005). After adjustment, higher CCS was independently associated with better global ventricular longitudinal strain/early diastolic strain rate, lower matrix metalloproteinase‐2, and N‐terminal propeptide of procollagen type III levels (adjusted coef: −0.08 and −19.9, all P < 0.05). During a median follow‐up of 1406 days (interquartile range: 1342‑1720 days), CCS less than 3.28% as a cut‐off had markedly higher HF events [Harrell's C: 0.72, adjusted HR: 2.20 (95% confidence interval: 1.24, 3.16), P = 0.008]. CCS also showed significantly improved risk prediction for HF over global ventricular longitudinal strain (net reclassification index: 48%, P = 0.001; integrated discrimination improvement: 1.8%, P < 0.001).

Conclusions

Carotid artery deformations using two‐dimensional speckle‐tracking imaging showed novel mechanistic insights on functional arterial alterations reflecting coupled arterial‐ventricular pathophysiology. Utilization of such measure may further provide additive prognostic value to advanced myocardial functional assessment.

The effect of lifelong endurance exercise on cardiovascular structure and exercise function in women

KEY POINTS

The beneficial effects of sustained or lifelong (>25 years) endurance exercise on cardiovascular structure and exercise function have been largely established in men. The current findings indicate that committed (≥4 weekly exercise sessions) lifelong exercise results in substantial benefits in exercise capacity ( V ̇ O 2 max ), cardiovascular function at submaximal and maximal exercise, left ventricular mass and compliance, and blood volume compared to similarly aged or even younger (middle-age) untrained women. Endurance exercise training should be considered a key strategy to prevent cardiovascular disease with ageing in women as well as men.

ABSTRACT

This study was a retrospective, cross-sectional analysis of exercise performance and left ventricular (LV) morphology in 70 women to examine whether women who have performed regular, lifelong endurance exercise acquire the same beneficial adaptations in cardiovascular structure and function and exercise performance that have been reported previously in men. Three groups of women were examined: (1) 35 older (>60 years) untrained women (older untrained, OU), (2) 13 older women who had consistently performed four or more endurance exercise sessions weekly for at least 25 years (older trained, OT), and (3) 22 middle-aged (range 35-59 years) untrained women (middle-aged untrained, MU) as a reference control for the appropriate age-related changes. Oxygen uptake ( V ̇ O 2 ) and cardiovascular function (cardiac output ( Q ̇ ); stroke volume (SV) acetylene rebreathing) were examined at rest, steady-state submaximal exercise and maximal exercise (maximal oxygen uptake, V ̇ O 2 max ). Blood volume (CO rebreathing) and LV mass (cardiac magnetic resonance imaging), plus invasive measures of static and dynamic chamber compliance were also examined. V ̇ O 2 max (p < 0.001) and maximal exercise Q ̇ and SV were larger in older trained women compared to the two untrained groups (∼17% and ∼27% for Q ̇ and SV, respectively, versus MU; ∼40% and ∼38% versus OU, all p < 0.001). Blood volume (mL kg^-1 ) and LV mass index (g m^-2 ) were larger in OT versus OU (∼11% and ∼16%, respectively, both P ≤ 0.015) Static LV chamber compliance was greater in OT compared to both untrained groups (median (25-75%): MU: 0.065 (0.049-0.080); OU: 0.085 (0.061-0.138); OT: 0.047 (0.031-0.054), P ≤ 0.053). Collectively, these findings indicate that lifetime endurance exercise appears to be extremely effective at preserving or even enhancing cardiovascular structure and function with advanced age in women.

The influence of sex on left ventricular remodeling in arterial hypertension

Hypertension represents one of the most important and most frequent cardiovascular risk factors responsible for heart failure (HF) development. Both sexes are equally affected by arterial hypertension. The difference is lying in the fact that prevalence of hypertension as well as hypertension-induced target organ damage varies during lifetime due to substantial variation of sex hormones in women. Left ventricular (LV) structural, functional, and mechanical changes induced by hypertension are well-known complications that occur in both sexes and they are responsible for HF development. However, their prevalence is significantly different between women and men, which could potentially explain the variation in HF occurrence and prognosis between the sexes. Studies have shown that the prevalence of left ventricular hypertrophy is higher in men. The data are not consistent regarding LV diastolic dysfunction and a similar report has been given for LV mechanical changes. Most investigations agree that LV longitudinal strain is lower among hypertensive men. However, even in the healthy population, men have lower LV longitudinal strain and the cutoff values are still missing. Therefore, it would be difficult to draw the conclusion that LV mechanical dysfunction is more prevalent among men. The main mechanisms responsible for sex-related LV remodeling are sex hormones and their influence on biohumoral systems. This review provides an updated overview of the available data about sex-related LV remodeling, as well as potential mechanisms for these changes, in the patients with arterial hypertension.

Elevated exercise blood pressure in middle-aged women is associated with altered left ventricular and vascular stiffness

Women are at higher risk for developing heart failure with preserved ejection fraction (HFpEF). We examined the utility of peak exercise blood pressure (BP) in identifying preclinical features of HFpEF, namely vascular and cardiac stiffness in middle-aged women. We studied 47 healthy, nonobese middle-aged women (53 ± 5 yr). Oxygen uptake (V̇o₂) and BP were assessed at rest and maximal treadmill exercise. Resting cardiac function and stiffness were assessed by echocardiography and invasive measurement (right heart catheterization) of left ventricular (LV) filling pressure under varying preloads. LV stiffness was calculated by curve fit of the diastolic portion of the pressure-volume curve. Aortic pulse-wave velocity was measured by arterial tonometry. Body fat was measured using dual-energy X-ray absorptiometry. Subjects in the highest exercise BP tertile had peak systolic BP of 201 ± 11 compared with 142 ± 19 mmHg in the lowest tertile (P < 0.001). Higher exercise BP was associated with increased age, percentage body fat, smaller LV size, slower LV relaxation, and increased LV and vascular stiffness. After adjustment, LV and arterial stiffness remained significantly associated with peak exercise BP. There was a trend toward increased body fat and slowed LV relaxation (both P < 0.07). In otherwise healthy middle-aged women, elevated exercise BP was independently associated with increased vascular stiffness and a smaller, stiffer LV, functional and structural risk factors characteristic for stages A and B HFpEF.NEW & NOTEWORTHY Women are at increased risk for heart failure with preserved ejection fraction (HFpEF) largely due to higher prevalence of arterial and cardiac stiffening. We were able to identify several subclinical markers of early (stages A and B) HFpEF pathophysiology largely on the basis of exercise blood pressure (BP) response in otherwise healthy middle-aged women. Exercise BP response may be an inexpensive screening tool to identify women at highest risk for developing future HFpEF.

Muscle metaboreflex-induced increases in effective arterial elastance: effect of heart failure

Dynamic exercise elicits robust increases in sympathetic activity in part due to muscle metaboreflex activation (MMA), a pressor response triggered by activation of skeletal muscle afferents. MMA during dynamic exercise increases arterial pressure by increasing cardiac output via increases in heart rate, ventricular contractility, and central blood volume mobilization. In heart failure, ventricular function is compromised, and MMA elicits peripheral vasoconstriction. Ventricular-vascular coupling reflects the efficiency of energy transfer from the left ventricle to the systemic circulation and is calculated as the ratio of effective arterial elastance (E_a) to left ventricular maximal elastance (E_max). The effect of MMA on E_a in normal subjects is unknown. Furthermore, whether muscle metaboreflex control of E_a is altered in heart failure has not been investigated. We utilized two previously published methods of evaluating E_a [end-systolic pressure/stroke volume (E_aPV)] and [heart rate × vascular resistance (E_aZ)] during rest, mild treadmill exercise, and MMA (induced via partial reductions in hindlimb blood flow imposed during exercise) in chronically instrumented conscious canines before and after induction of heart failure via rapid ventricular pacing. In healthy animals, MMA elicits significant increases in effective arterial elastance and stroke work that likely maintains ventricular-vascular coupling. In heart failure, E_a is high, and MMA-induced increases are exaggerated, which further exacerbates the already uncoupled ventricular-vascular relationship, which likely contributes to the impaired ability to raise stroke work and cardiac output during exercise in heart failure.

Acute impact of changes to hemodynamic load on the left ventricular strain-volume relationship in young and older men

Chronic changes in left ventricular (LV) hemodynamics, such as those induced by increased afterload (i.e., hypertension), mediate changes in LV function. This study examined the proof of concept that 1) the LV longitudinal strain (ε)-volume loop is sensitive to detecting an acute increase in afterload, and 2) these effects differ between healthy young versus older men. Thirty-five healthy male volunteers were recruited, including 19 young (24 ± 2 yr) and 16 older participants (67 ± 5 yr). Tests were performed before, during, and after 10-min recovery from acute manipulation of afterload. Real-time hemodynamic data were obtained and LV longitudinal ε-volume loops were calculated from four-chamber images using two-dimensional echocardiography. Inflation of the anti-gravity (anti-G) suit resulted in an immediate increase in heart rate, blood pressure, and systemic vascular resistance and a decrease in stroke volume (all P < 0.05). This was accompanied by a decrease in LV peak ε, slower slope of the ε-volume relationship during early diastole, and an increase in uncoupling (i.e., compared with systole; little change in ε per volume decline during early diastole and large changes in ε per volume decline during late diastole) (all P < 0.05). All values returned to baseline levels after recovery (all P > 0.05). Manipulation of cardiac hemodynamics caused comparable effects in young versus older men (all P > 0.05). Acute increases in afterload immediately change the diastolic phase of the LV longitudinal ε-volume loop in young and older men. This supports the potency of the LV longitudinal ε-volume loop to provide novel insights into dynamic cardiac function in humans in vivo.

Paradoxical Higher Myocardial Wall Stress and Increased Cardiac Remodeling Despite Lower Mass in Females

Background

Increased left ventricular (LV) mass is characterized by increased myocardial wall thickness and/or ventricular dilatation that is associated with worse outcomes. We aim to comprehensively compare sex‐stratified associations between measures of LV remodeling and increasing LV mass in the general population.

Methods and Results

Participants were prospectively recruited in the National Heart Center Singapore Biobank to examine health and cardiovascular risk factors in the general population. Cardiovascular magnetic resonance was performed in all individuals. Participants with established cardiovascular diseases and abnormal cardiovascular magnetic resonance scan results were excluded. Global and regional measures of LV remodeling (geometry, function, interstitial volumes, and wall stress) were performed using conventional image analysis and novel 3‐dimensional machine learning phenotyping. Sex‐stratified analyses were performed in 1005 participants (57% males; 53±13 years). Age and prevalence of cardiovascular risk factors were well‐matched in both sexes (P>0.05 for all). Progressive increase in LV mass was associated with increased concentricity in either sex, but to a greater extent in females. Compared with males, females had higher wall stress (mean difference: 170 mm Hg, P<0.0001) despite smaller LV mass (42.4±8.2 versus 55.6±14.2 g/m², P<0.0001), lower blood pressures (P<0.0001), and higher LV ejection fraction (61.9±5.9% versus 58.6±6.4%, P<0.0001). The regions of increased concentric remodeling corresponded to regions of increased wall stress. Compared with males, females had increased extracellular volume fraction (27.1±2.4% versus 25.1±2.9%, P<0.0001).

Conclusions

Compared with males, females have lower LV mass, increased wall stress, and concentric remodeling. These findings provide mechanistic insights that females are susceptible to particular cardiovascular complications.

Association of estimated plasma volume status with hemodynamic and echocardiographic parameters

BACKGROUND

Estimated plasma volume status (ePVS) has diagnostic and prognostic value in patients with heart failure (HF). However, it remains unclear which congestion markers (i.e., biological, imaging, and hemodynamic markers) are preferentially associated with ePVS. In addition, there is evidence of sex differences in both the hematopoietic process and myocardial structure/function.

METHOD AND RESULTS

Patients with significant dyspnea (NYHA ≥ 2) underwent echocardiography and lung ultrasound within 4 h prior to cardiac catheterization. Patients were divided according to tertiles based on sex-specific ePVS thresholds calculated from hemoglobin and hematocrit measurements using Duarte's formula. Among the 78 included patients (median age 74.5 years; males 69.2%; HF 48.7%), median ePVS was 4.1 (percentile_25-75 = 3.7-4.9) mL/g in males (N = 54) and 4.8 (4.4-5.3) mL/g in females (N = 24). Patients with the highest ePVS had more frequently HF, higher NT-proBNP, larger left atrial volume, and higher E/e' (all p values < 0.05), but no difference in inferior vena cava diameter or pulmonary congestion assessed by lung ultrasound (all p values > 0.10). In multivariable analysis, higher E/e' and lower diastolic blood pressure were significantly associated with increased ePVS. The association between ePVS and congestion variables was not sex-dependent except for left-ventricular end-diastolic pressure, which was only correlated with ePVS in females (Spearman Rho = 0.53, p < 0.01 in females and Spearman Rho = - 0.04, p = 0.76 in males; p_interaction = 0.08).

CONCLUSION

ePVS is associated with E/e' regardless of sex, while only associated with invasively measured left-ventricular end-diastolic pressure in females. These results suggest that ePVS is preferably associated with left-sided hemodynamic markers of congestion.

Mechanical and structural changes in human thoracic aortas with age

Aortic mechanical and structural characteristics have profound effects on pathophysiology, but many aspects of physiologic stress-stretch state and intramural changes due to aging remain poorly understood in human tissues. While difficult to assess in vivo due to residual stresses and pre-stretch, physiologic stress-stretch characteristics can be calculated using experimentally-measured mechanical properties and constitutive modeling. Mechanical properties of 76 human descending thoracic aortas (TA) from 13 to 78-year-old donors (mean age 51±18 years) were measured using multi-ratio planar biaxial extension. Constitutive parameters were derived for aortas in 7 age groups, and the physiologic stress-stretch state was calculated. Intramural characteristics were quantified from histological images and related to aortic morphometry and mechanics. TA stiffness increased with age, and aortas became more nonlinear and anisotropic. Systolic and diastolic elastic energy available for pulsation decreased with age from 30 to 8 kPa and from 18 to 5 kPa, respectively. Cardiac cycle circumferential stretch dropped from 1.14 to 1.04, and circumferential and longitudinal physiologic stresses decreased with age from 90 to 72 kPa and from 90 to 17 kPa, respectively. Aortic wall thickness and radii increased with age, while the density of elastin in the tunica media decreased. The number of elastic lamellae and circumferential physiologic stress per lamellae unit remained constant with age at 102±10 and 0.85±0.04 kPa, respectively. Characterization of mechanical, physiological, and structural features in human aortas of different ages can help understand aortic pathology, inform the development of animal models that simulate human aging, and assist with designing devices for open and endovascular aortic repairs. STATEMENT OF SIGNIFICANCE: This manuscript describes mechanical and structural changes occurring in human thoracic aortas with age, and presents material parameters for 4 commonly used constitutive models. Presented data can help better understand aortic pathology, inform the development of animal models that simulate human aging, and assist with designing devices for open and endovascular aortic repairs.

Diagnosis and treatment of heart failure with preserved left ventricular ejection fraction

Nearly six million people in United States have heart failure. Fifty percent of these people have normal left ventricular (LV) systolic heart function but abnormal diastolic function due to increased LV myocardial stiffness. Most commonly, these patients are elderly women with hypertension, ischemic heart disease, atrial fibrillation, obesity, diabetes mellitus, renal disease, or obstructive lung disease. The annual mortality rate of these patients is 8%-12% per year. The diagnosis is based on the history, physical examination, laboratory data, echocardiography, and, when necessary, by cardiac catheterization. Patients with obesity, hypertension, atrial fibrillation, and volume overload require weight reduction, an exercise program, aggressive control of blood pressure and heart rate, and diuretics. Miniature devices inserted into patients for pulmonary artery pressure monitoring provide early warning of increased pulmonary pressure and congestion. If significant coronary heart disease is present, coronary revascularization should be considered.

Heart failure with preserved ejection fraction: Similarities and differences between women and men

The syndrome of heart failure (HF) with preserved ejection fraction (HFpEF) is now recognized to account for up to half of HF cases and is the dominant form of HF in older adults, especially women. Multiple factors conspire in this predilection of HFpEF for older women. This review will discuss the epidemiology, pathophysiology, prognosis, and treatment of HFpEF with emphasis on the similarities and differences in cardiovascular aging changes, and the differential impact of comorbidities in women versus men. Responses to pharmacologic and lifestyle interventions are also reviewed. We conclude by suggesting future directions for both prevention and treatment of this common and highly morbid cardiovascular disorder.

Considerable scatter in the relationship between left atrial volume and pressure in heart failure with preserved left ventricular ejection fraction

The index for a target that can lead to improved prognoses and more reliable therapy in each heterogeneous patient with heart failure with preserved ejection fraction (HFpEF) remains to be defined. We examined the heterogeneity in the cardiac performance of patients with HFpEF by clarifying the relationship between the indices of left atrial (LA) volume (LAV) overload and pressure overload with echocardiography. We enrolled patients with HFpEF (N = 105) who underwent transthoracic echocardiography during stable sinus rhythm. Relative LAV overload was evaluated using the LAV index or stroke volume (SV)/LAV ratio. Relative LA pressure overload was estimated using E/e' or the afterload-integrated index of left ventricular (LV) diastolic function: diastolic elastance (Ed)/arterial elastance (Ea) ratio = (E/e')/(0.9 × systolic blood pressure). The logarithmic value of the N-terminal pro-brain natriuretic peptide was associated with SV/LAV (r = -0.214, p = 0.033). The pulmonary capillary wedge pressure was positively correlated to Ed/Ea (r = 0.403, p = 0.005). SV/LAV was negatively correlated to Ed/Ea (r = -0.292, p = 0.002), with no observed between-sex differences. The correlations between the LAV index and E/e' and Ed/Ea and between SV/LAV and E/e' were less prominent than the abovementioned relationships. SV/LAV and Ed/Ea, showing relative LAV and LA pressure respectively, were significantly but modestly correlated in patients with HFpEF. There may be considerable scatter in the relationships between these indices, which could possibly affect the selection of medications or efforts to improve the prognoses of patients with HFpEF.

Gender Differences in Risk Factors Associated With Pulmonary Artery Systolic Pressure, Heart Failure, and Mortality in Blacks: Jackson Heart Study

Background

Pulmonary hypertension is prevalent in black individuals, especially women. Elevated pulmonary artery systolic pressure (PASP) is associated with significant morbidity and mortality.

Methods and Results

We developed linear and proportional hazards models to examine potential gender‐related differences in risk factors for elevated PASP (estimated by transthoracic echocardiography) and PASP‐associated clinical outcomes (incident heart failure admissions and mortality) in JHS (Jackson Heart Study) participants. JHS is a prospective observational cohort study of heart disease in blacks from the Jackson, Mississippi, metropolitan area. The study cohort included participants with measurable transtricuspid gradients (n=3286) at the time of first/baseline examination, 2000–2004. The median age (interquartile range) of patients at baseline was 57.8 years (18.6 years) with 67.5% being women. The median PASP at baseline was higher in women (men: 26 mm Hg [interquartile range 8], women: 27 mm Hg [interquartile range 9]. In multivariate linear regression analyses with PASP, significant gender interactions were noted for age, chronic lung disease, pulse pressure, and obstructive spirometry. In exploratory analyses stratified by gender, body mass index, and obstructive and restrictive spirometry patterns were associated with PASP in women, and chronic lung disease was associated with PASP in men. Age and pulse pressure had stronger associations with PASP in women compared with men. There was a significant interaction between gender and PASP for heart failure admissions but not mortality.

Conclusions

Specific cardiopulmonary risk factors are associated with elevated PASP in women and men. Women with elevated PASP have a higher risk of incident heart failure admissions. Future research is needed to understand associated gender‐specific mechanisms that can help identify targeted prevention and management strategies for patients with elevated PASP.

Endovascular Repair of Blunt Thoracic Aortic Trauma is Associated With Increased Left Ventricular Mass, Hypertension, and Off-target Aortic Remodeling

BACKGROUND

Aortic elasticity creates a cushion that protects the heart from pressure injury, and a recoil that helps perfuse the coronary arteries. TEVAR has become first-line therapy for many aortic pathologies including trauma, but stent-grafts stiffen the aorta and likely increase LV afterload.

OBJECTIVE

Test the hypothesis that trauma TEVAR is associated with LV mass increase and adverse off-target aortic remodeling.

METHODS

Computed Tomography Angiography (CTA) scans of 20 trauma TEVAR patients (17 M/3 F) at baseline [age 34.9 ± 18.5 (11.4-71.5) years] and 5.1 ± 3.1 (1.1-12.3) years after repair were used to measure changes in LV mass, LV mass index, and diameters and lengths of the ascending thoracic aorta (ATA). Measurements were compared with similarly-aged control patients without aortic repair (21 M/21 F) evaluated at similar follow-ups.

RESULTS

LV mass and LV mass index of TEVAR patients increased from 138.5 ± 39.6 g and 72.35 ± 15.17 g/m to 173.5 ± 50.1 g and 85.48 ± 18.34 g/m at the rate of 10.03 ± 12.79 g/yr and 6.25 ± 10.28 g/m/yr, whereas in control patients LV characteristics did not change. ATA diameters of TEVAR patients increased at a rate of 0.60 ± 0.80 mm/yr, which was 2.4-fold faster than in controls. ATA length in both TEVAR and control patients increased at 0.58 mm/yr. Half of TEVAR patients had hypertension at follow-up compared to only 5% at baseline.

CONCLUSIONS

TEVAR is associated with LV mass increase, development of hypertension, and accelerated expansile remodeling of the ascending aorta. Although younger trauma patients may adapt to these effects, these changes may be even more important in older patients with other aortic pathologies and diminished baseline cardiac function.

Reduced Coronary Flow Reserve Is Associated with Impaired Ventricular-vascular Interaction in Patients with Obstructive Sleep Apnea

Background and Objectives

Obstructive sleep apnea (OSA) is associated with cardiac and arterial damage and adverse cardiovascular outcomes. We aimed to determine whether coronary flow reserve (CFR), which represents microvascular dysfunction, might be associated with the ventricular-vascular coupling index (VVI), which represents the afterload-adjusted contractility in patients with OSA.

Methods

We enrolled 281 patients (257 males; mean age, 43±11 years) with newly diagnosed OSA. Transthoracic echocardiography was performed, and adenosine-associated CFR was measured in the left anterior descending coronary artery. We evaluated the differences between the patients with normal CFR ≥2.5 and reduced CFR <2.5. VVI was calculated using the effective arterial elastance (Ea) and left ventricular (LV) end-systolic elastance (Ees) as follows: 10×Ea/Ees.

Results

The normal CFR group (n=214) showed increased Ees (7.28±2.31 vs. 8.14±2.33 mmHg/mL, p=0.016) and preserved VVI (3.17±1.53 vs. 2.78±1.20, p=0.044) compared with the reduced CFR group (n=67). There were no differences in LV dimension, LV ejection fraction, left atrial-volume index, E/e′, left atrial strain and LV global longitudinal strain between the 2 groups (all p>0.05). CFR was significantly correlated to Ees (r=0.139; p=0.023) and VVI (r=−0.137; p=0.025).

Conclusions

Reduced CFR is associated with decreased Ees and impaired VVI in OSA patients. It suggests the necessity of more intensive observation in OSA patients with reduced CFR to improve cardiovascular outcomes.

Sex Differences in Cardiometabolic Traits and Determinants of Exercise Capacity in Heart Failure With Preserved Ejection Fraction

Importance

Sex differences in heart failure with preserved ejection fraction (HFpEF) have been established, but insights into the mechanistic drivers of these differences are limited.

Objective

To examine sex differences in cardiometabolic profiles and exercise hemodynamic profiles among individuals with HFpEF.

Design, Setting, and Participants

This cross-sectional study was conducted at a single-center tertiary care referral hospital from December 2006 to June 2017 and included 295 participants who met hemodynamic criteria for HFpEF based on invasive cardiopulmonary exercise testing results. We examined sex differences in distinct components of oxygen transport and utilization during exercise using linear and logistic regression models. The data were analyzed from June 2018 to May 2019.

Main Outcomes and Measures

Resting and exercise gas exchange and hemodynamic parameters obtained during cardiopulmonary exercise testing.

Results

Of 295 participants, 121 (41.0%) were men (mean [SD] age, 64 [12] years) and 174 (59.0%) were women (mean [SD] age, 61 [13] years). Compared with men, women with HFpEF in this tertiary referral cohort had fewer comorbidities, including diabetes, insulin resistance, and hypertension, and a more favorable adipokine profile. Exercise capacity was similar in men and women (percent predicted peak oxygen [O2] consumption: 66% in women vs 68% in men; P = .38), but women had distinct deficits in components of the O2 pathway, including worse biventricular systolic reserve (multivariable-adjusted analyses: ΔLVEF β = -1.70; SE, 0.86; P < .05; ΔRVEF β = -2.39, SE=0.80; P = .003), diastolic reserve (PCWP/CO: β = 0.63; SE, 0.31; P = .04), and peripheral O2 extraction (C(a-v)O2 β=-0.90, SE=0.22; P < .001)).

Conclusions and Relevance

Despite a lower burden of cardiometabolic disease and a similar percent predicted exercise capacity, women with HFpEF demonstrated greater cardiac and extracardiac deficits, including systolic reserve, diastolic reserve, and peripheral O2 extraction. These sex differences in cardiac and skeletal muscle responses to exercise may illuminate the pathophysiology underlying the development of HFpEF and should be investigated further.

EVALUATION INDEX OF ADULT MALE BLOOD VESSEL AGE-BASED ON PULSE WAVE WAVEFORM CHARACTERISTIC PARAMETERS

The aim of this study was to find a non-invasive pulse wave waveform index that was highly correlated with cardiovascular disease and to establish an effective model for cardiovascular health assessment in middle-aged men to provide early warning of possible cardiovascular and cerebrovascular diseases. Considering the characteristics of pulse wave easy to detect and rich physiological information, the paper collected pulse waves of healthy males at six age groups, and collected 50 samples per age group. The pulse wave waveform parameters of each sample were extracted, including inflow time, outflow time, total beat time, fast inflow time, inflow time ratio and waveform coefficient [Formula: see text] value, the differences of which in different age groups were analyzed. Stepwise regression analysis was used to establish the relationship between age and pulse waveform parameters. The results show that the indicators of inflow time, inflow time ratio and fast inflow time have obvious differences with age, and with the increase of age, these three indicators show a steady upward trend. The indicators of outflow time, total beat time, and waveform coefficient are not sensitive to age changes. A predictive model of vessel age was established: [Formula: see text] time ([Formula: see text]). The pulse wave inflow time of hypertensive patients was substituted into the above-mentioned model, and the calculated blood vessel age was greater than the actual age. The age difference is greater than 5 years old. This study suggests that the pulse wave parameters of inflow time, fast inflow time and inflow time ratio has a significant and stable trend with age, indicating that they are closely related to vascular elasticity, compliance and stiffness, and can be used as predictors of cardiovascular disease.

Sex differences in heart failure

The overall lifetime risk of heart failure (HF) is similar between men and women, however, there are marked sex differences in the landscape of this condition that are both important and under-recognized. Men are predisposed to HF with reduced ejection fraction (HFrEF), whereas women predominate in HF with preserved ejection fraction (HFpEF). Sex differences are also notable in the penetrance of genetic cardiomyopathies, risk factors, e.g. breast cancer which may be associated with cancer treatment-induced cardiomyopathy, as well as sex-specific conditions such as peripartum cardiomyopathy (PPCM). This review outlines the key sex differences with respect to clinical characteristics, pathophysiology, and therapeutic responses to HF treatments. Finally, we address important differences in the prognosis of HF. A central hypothesis is that the higher risk of HFrEF in men compared to women may be attributable to their predisposition to macrovascular coronary artery disease and myocardial infarction, whereas coronary microvascular dysfunction/endothelial inflammation has been postulated to play a key role in HFpEF and maybe the common link among HF syndromes that women are predisposed to Takotsubo cardiomyopathy, PPCM, and breast cancer radiotherapy-induced cardiomyopathy. Under-pinning current sex disparities in HF, there is a paucity of women recruited to HF clinical trials (20–25% of cohorts) and thus treatment guidelines are predominantly based on male-derived data. Large gaps in knowledge exist in sex-specific mechanisms, optimal drug doses for women and sex-specific criteria for device therapy.

Effects of Sacubitril-Valsartan Versus Valsartan in Women Compared With Men With Heart Failure and Preserved Ejection Fraction: Insights From PARAGON-HF

BACKGROUND

Unlike heart failure with reduced ejection fraction, there is no approved treatment for heart failure with preserved ejection fraction, the predominant phenotype in women. Therefore, there is a greater heart failure therapeutic deficit in women compared with men.

METHODS

In a prespecified subgroup analysis, we examined outcomes according to sex in the PARAGON-HF trial (Prospective Comparison of ARNI With ARB Global Outcomes in Heart Failure With Preserved Ejection Fraction), which compared sacubitril-valsartan and valsartan in patients with heart failure with preserved ejection fraction. The primary outcome was a composite of first and recurrent hospitalizations for heart failure and death from cardiovascular causes. We also report secondary efficacy and safety outcomes.

RESULTS

Overall, 2479 women (51.7%) and 2317 men (48.3%) were randomized. Women were older and had more obesity, less coronary disease, and lower estimated glomerular filtration rate and NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels than men. For the primary outcome, the rate ratio for sacubitril-valsartan versus valsartan was 0.73 (95% CI, 0.59-0.90) in women and 1.03 (95% CI, 0.84-1.25) in men (P interaction = 0.017). The benefit from sacubitril-valsartan was attributable to reduction in heart failure hospitalization. The improvement in New York Heart Association class and renal function with sacubitril-valsartan was similar in women and men, whereas the improvement in Kansas City Cardiomyopathy Questionnaire clinical summary score was less in women than in men. The difference in adverse events between sacubitril-valsartan and valsartan was similar in women and men.

CONCLUSIONS

As compared with valsartan, sacubitril-valsartan seemed to reduce the risk of heart failure hospitalization more in women than in men. Whereas the possible sex-related modification of the effect of treatment has several potential explanations, the present study does not provide a definite mechanistic basis for this finding.

CLINICAL TRIAL REGISTRATION

https://www.clinicaltrials.gov. Unique identifier: NCT01920711.

Trends in the off-label use of β-blockers in pediatric patients

The use of US Food and Drug Administration (FDA)-approved drugs for the treatment of an unapproved indication or in an unapproved age group, or at doses or route of administration not indicated on the label is known as off-label use. Off-label use may be beneficial in circumstances when the standard-of-care treatment has failed, and/or no other FDA-approved medications are available for a particular condition. In pediatric patients, off-label use may increase the risk of adverse events as pharmacokinetic and pharmacodynamic data are limited in children. Approximately 73% of off-label drugs currently prescribed for various conditions do not have sufficient scientific evidence for safety and efficacy. For example, β-blockers are a class of drugs with FDA-approval for very few indications in pediatrics but are commonly used for various off-label indications. Interestingly, the proportion of off-label use of β-blockers in adults is at about 52% (66.2 million) of the total number of β-blockers prescribed. The frequency of off-label use of β-blockers in children is also high with limited data on the indications as well as safety and efficacy. We present trends in off-label use of β-blockers in children to discuss drug safety and efficacy and include recommendations for pediatric providers.

Modeling arterial pulse waves in healthy aging: a database for in silico evaluation of hemodynamics and pulse wave indexes

The arterial pulse wave (PW) is a rich source of information on cardiovascular (CV) health. It is widely measured by both consumer and clinical devices. However, the physical determinants of the PW are not yet fully understood, and the development of PW analysis algorithms is limited by a lack of PW data sets containing reference CV measurements. Our aim was to create a database of PWs simulated by a computer to span a range of CV conditions, representative of a sample of healthy adults. The typical CV properties of 25-75 yr olds were identified through a literature review. These were used as inputs to a computational model to simulate PWs for subjects of each age decade. Pressure, flow velocity, luminal area, and photoplethysmographic PWs were simulated at common measurement sites, and PW indexes were extracted. The database, containing PWs from 4,374 virtual subjects, was verified by comparing the simulated PWs and derived indexes with corresponding in vivo data. Good agreement was observed, with well-reproduced age-related changes in hemodynamic parameters and PW morphology. The utility of the database was demonstrated through case studies providing novel hemodynamic insights, in silico assessment of PW algorithms, and pilot data to inform the design of clinical PW algorithm assessments. In conclusion, the publicly available PW database is a valuable resource for understanding CV determinants of PWs and for the development and preclinical assessment of PW analysis algorithms. It is particularly useful because the exact CV properties that generated each PW are known.NEW & NOTEWORTHY First, a comprehensive literature review of changes in cardiovascular properties with age was performed. Second, an approach for simulating pulse waves (PWs) at different ages was designed and verified against in vivo data. Third, a PW database was created, and its utility was illustrated through three case studies investigating the determinants of PW indexes. Fourth, the database and tools for creating the database, analyzing PWs, and replicating the case studies are freely available.

Muscle strength is a major determinant of the blood pressure response to isometric stress testing: the Asklepios population study

AIM

Maximal handgrip strength is a strong predictor of cardiovascular mortality in economically and socioculturally diverse countries, yet the main determinants of cardiovascular response to change in afterload during handgrip are not well known. We examined the blood pressure (BP) responses during submaximal handgrip (at 25% of grip strength) and the determinants of grip strength.

METHODS

We studied 2215 participants from a population-based random sample without overt clinical disease (Asklepios Study; mean age 56.2 years). Handgrip testing was performed using a modified Jamar dynamometer with direct visual feedback. Simultaneously, a validated finger plethysmographic device measured continuous BP and heart rate.

RESULTS

During handgrip, SBP and DBP rose by, respectively, 20 ± 13 and 10 ± 6 mmHg. These changes were normally distributed and consistently higher in men. The main independent determinants of mean arterial pressure response during handgrip were: grip strength (F = 191.4; P < 0.001), baseline pulse pressure (F = 32.0; P < 0.001), height (F = 16.4; P < 0.001) and age (F = 12.8; P < 0.001). Grip strength was associated with muscle mass, better metabolic health, but also with higher baseline DBP. There was a significant graded increase in maximum pressure achieved and in the magnitude of pressure change during handgrip with increasing BP categories (P for trend <0.001).

CONCLUSION

The population BP response to handgrip is variable and its predominant determinant turned out to be grip strength itself, which should be accounted for in future analyses. Higher baseline BP, even within the normotensive range, acted as an independent and graded predictor of BP increase during handgrip.

Sex Differences in Cardiovascular Pathophysiology: Why Women Are Overrepresented in Heart Failure With Preserved Ejection Fraction

Consistent epidemiological data demonstrate that patients with heart failure with preserved ejection fraction (HFpEF) are more likely to be women than men. Exploring mechanisms behind this sex difference in heart failure epidemiology may enrich the understanding of underlying HFpEF pathophysiology and phenotypes, with the ultimate goal of identifying therapeutic approaches for the broader HFpEF population. In this review we evaluate the influence of sex on the key domains of cardiac structure and function, the systemic and pulmonary circulation, as well as extracardiac factors and comorbidities that may explain the predisposition of women to HFpEF. We highlight the potential role of factors exclusive to or more prevalent in women such as pregnancy, preeclampsia, and iron deficiency. Finally, we discuss existing controversies and gaps in knowledge, as well as the clinical importance of known sex differences in the context of the potential need for sex-specific diagnostic criteria, improved risk stratification models, and targeted therapies.

Sex differences on peak oxygen uptake in heart failure

Women represent nearly half of the adult heart failure (HF) population and they remain underrepresented in HF studies. We aimed to evaluate the evidence about peak oxygen uptake (peak VO₂) for clinical stratification in women with HF. This narrative review summarizes (i) the evidence endorsing the value of cardiopulmonary exercise testing for clinical stratification and phenotyping HF population; (ii) the determinants of a person's functional aerobic capacity to understand predicted values for patients with chronic HF; and (iii) sex differences on peak VO₂ data in different forms of HF. Lastly, based on existing data in patients with HF, we provide a perspective on how to improve existing gaps about the utility of peak VO₂ in clinical stratification in women. Peak VO₂ provides prognosis information in patients with HF; however, its use has been limited for a reduced number of patients excluding women, elderly, and HF patients with preserved ejection fraction. Further studies will help to fill the wide gender gap about the utility of cardiopulmonary exercise testing in the risk assessment and management in women with HF.