Arterial Stiffening With Exercise in Patients With Heart Failure and Preserved Ejection Fraction. J Am Coll Cardiol. 2017;70:136-148. [PMID: 28683960 DOI: 10.1016/j.jacc.2017.05.029]

Exercise Intolerance in Patients With Heart Failure: JACC State-of-the-Art Review

Exercise intolerance is the cardinal symptom of heart failure (HF) and is of crucial relevance, because it is associated with a poor quality of life and increased mortality. While impaired cardiac reserve is considered to be central in HF, reduced exercise and functional capacity are the result of key patient characteristics and multisystem dysfunction, including aging, impaired pulmonary reserve, as well as peripheral and respiratory skeletal muscle dysfunction. We herein review the different modalities to quantify exercise intolerance, the pathophysiology of HF, and comorbid conditions as they lead to reductions in exercise and functional capacity, highlighting the fact that distinct causes may coexist and variably contribute to exercise intolerance in patients with HF.

Epidemiology, pathophysiology, and prevention of heart failure in people with HIV

Heart failure (HF) has been a known complication of HIV/AIDS for three decades. As the treatment of HIV has changed, so has the epidemiology and pathophysiology of HF in people with HIV (PWH). Initial manifestations of HF in uncontrolled HIV primarily included a rapidly evolving cardiomyopathy with pericardial involvement. With the widespread uptake of effective antiretroviral therapy (ART), HF in PWH has become a chronic disease reflective of the aging population and associated comorbidities, albeit with a contribution from HIV-associated chronic immune dysregulation and inflammation. Despite viral suppression, PWH remain at elevated risk for both HF with reduced ejection fraction and HF with preserved ejection fraction. In this review, we discuss the changing epidemiology and mechanisms of HF in PWH and how that may inform HF prevention in this vulnerable population.

Hemodynamic assessment in heart failure

Hemodynamics play a central role in the pathophysiology of heart failure (HF), yet their proper assessment and optimization remains challenging. Heart failure is defined as the inability of the heart to deliver adequate perfusion (cardiac output) to the body at rest or exercise, or to require an elevation in cardiac filling pressures in order to do this. This bedrock definition is important because it relies on measurable quantities (filling pressures and output) that are readily assessed in the cardiac catheterization laboratory. Here we present three cases to illustrate how better understanding of the determinants of cardiac output and stroke volume: preload, afterload, contractility, and lusitropy, as well as the determinants of congestion (high filling pressures) may be used to guide optimization of hemodynamic status. The goal is that the readers will be able to think more critically when evaluating the hemodynamics of their patient in HF and recognize the complex interplay that determines the complex balance between cardiac ejection and filling capabilities, and how this alters symptoms and outcomes for patients with HF. KEY POINTS: Careful assessment of hemodynamics in the catheterization laboratory allows for actionable insight to a patient's volume status, cardiac function and can help prognosticate outcomes. Exercise hemodynamics in heart failure is a powerful tool to better understand the cause of symptoms and predict outcomes. Clinicians should aim to decrease biventricular filling pressures to normal values to improve morbidity and reduce risk for readmission. In patients with heart failure and reduced ejection fraction, clinicians should aim to decrease afterload as much as can be tolerated by the renal function and patient's symptoms. Low cardiac output can often be improved by optimizing preload and afterload rather than initiating inotropes, which should be reserved until needed. In advanced heart failure, the right heart function becomes a key determinant of symptoms and outcomes.

Doppler-Derived Arterial Load Indices Better Reflect Left Ventricular Afterload Than Systolic Blood Pressure in Coarctation of Aorta

BACKGROUND

Patients with vascular stiffening may display increased arterial afterload that is out of proportion to systolic blood pressure (SBP). Since vascular and endothelial dysfunction develop in patients with coarctation of aorta (COA), we hypothesized that for any SBP, patients with mild COA (COA peak velocity <2 m/s) will have a higher arterial afterload and increased left ventricular mass index (LVMI) compared with controls, and that Doppler-derived arterial load indices would be a better predictor of LVMI compared with SBP alone.

METHODS

We studied 204 COA patients (age 35±12 y) and 204 matched controls. Doppler-derived arterial afterload was assessed using effective arterial elastance index and total arterial compliance index.

RESULTS

Despite similar SBP, the mild COA group displayed higher arterial afterload as evidenced by a higher elastance index (3.3±0.9 versus 2.9±0.7 mm Hg/mL·m2; P<0.001) and lower total arterial compliance index (0.8±0.3 versus 1.2±0.5 mL/mm Hg·m2; P<0.001). This was associated with higher LVMI in COA (109±35 versus 93±32, g/m2; P<0.001). Compared with SBP (β=0.24 [95% CI, 0.02-0.45]), elastance index (β=20.2 [95% CI, 15.8-44.1]) and total arterial compliance index (β=-32.5 [95% CI, -43.8 to -123.6]) were better predictors of LVMI. Elastance index (but not SBP) was predictive of longitudinal increases in LVMI (r=0.43, P<0.001).

CONCLUSIONS

COA patients had higher arterial afterload compared with controls with similar SBP. In comparison to SBP, Doppler-derived arterial load indices correlate more strongly with LV hypertrophy. These data suggest that SBP may underestimate LV afterload in this population. This has important clinical implications since titration of antihypertensive therapy is currently based on SBP.

Left ventricular filling pressure in Tetralogy of Fallot: Correlation between invasive and noninvasive indices

Background

Left heart filling pressures, as measured by pulmonary artery wedge pressure (PAWP), is associated with heart failure related mortality. Because of the prognostic importance of PAWP, several echocardiographic indices have been proposed for noninvasive assessment of PAWP. However, these indices have not been validated in the congenital heart disease population. The purpose of this study was to determine the correlation between echocardiographic indices of PAWP, and the effect of high PAWP on transplant-free survival in adults with tetralogy of Fallot (TOF).

Methods

Retrospective study of adult TOF patients that underwent cardiac catheterization at Mayo Clinic, 1990–2017. We selected these pre-defined set of echocardiographic indices of LV diastolic function: mitral valve early velocity (E), mitral valve early and late velocity ratio (E/A), mitral valve deceleration time (DT), mitral annular tissue Doppler early velocity (e′), and left atrial volume index (LAVI).

Results

Of the echocardiographic indices analyzed among 213 patients (age 37 ± 14 years), only E velocity (β = 5.83, standard error = 1.52, p < 0.001) and LAVI (β = 0.14, standard error = 0.05, p = 0.007) correlated with PAWP. LAVI > 28 ml/m² had sensitivity of 79% and specificity of 63% (AUC 0.712), and E velocity > 1.0 m/s had sensitivity of 66% and specificity of 89% (AUC 0.692), for detecting PAWP > 15 mmHg. LAVI > 28 ml/m² was associated with reduced 10-year transplant-free survival (49% vs 90%, p < 0.001).

Conclusion

This study supports the use of LAVI for noninvasive assessment of PAWP and for prognostication. Further studies are required to validate these results in a different population.

Feasibility, reproducibility and accuracy of electrical velocimetry for cardiac output assessment in congenital heart disease

BACKGROUND

Noninvasive cardiac output assessment is important for prognostication in patients with heart failure. Electrical velocimetry (EV), an impedance cardiography technique, can be used for noninvasive cardiac output assessment. The purpose of this study was to determine the feasibility, reproducibility and accuracy of cardiac output assessment by EV in adults with congenital heart disease (CHD).

METHODS

Cross-sectional study of CHD patients that had simultaneous cardiac output assessment by Fick and EV (using Cardiotronic monitor, Osypka Medical). We divided the cohort into: Group 1 patients (n = 54) had hemodynamic assessment at rest only, while Group 2 patients (n = 7) had assessment both at rest and peak exercise.

RESULTS

EV cardiac output assessment was feasible in 100% of the patients. There was good correlation between Fick-derived and EV-derived cardiac index (r = 0.89, p < 0.001) in Group 1. Among 26 patients in Group 1 that underwent cardiac output assessment pre- and post-intervention, there was no difference in the strength of correlation of Fick and EV cardiac output pre- and post-intervention (p-interaction 0.244) indicating good reproducibility of the technique. There was also modest correlation between Fick-derived and EV-derived cardiac index at rest (r = 0.68, p = 0.032), and peak exercise (r = 0.62, p = 0.055), in Group 2.

CONCLUSION

In this study, we demonstrated the feasibility and accuracy of EV cardiac output assessment in adults with CHD. We also demonstrated, for the first time, that EV cardiac output assessment was reproducible under different loading conditions, and that EV can be used for the assessment of cardiac output augmentation at peak exercise.

Haemodynamic and metabolic phenotyping of hypertensive patients with and without heart failure by combining cardiopulmonary and echocardiographic stress test

AIM

We combined cardiopulmonary exercise test (CPET) and exercise stress echocardiography (ESE) to identify early haemodynamic and metabolic alterations in patients with hypertension (HT) with and without heart failure with preserved ejection fraction (HFpEF).

METHODS AND RESULTS

Fifty stable HFpEF-HT outpatients (mean age 68 ± 14 years) on optimal medical therapy, 63 well-controlled HT subjects (mean age 63 ± 11 years) and 32 age and sex-matched healthy controls (mean age 59 ± 15 years) underwent a symptom-limited graded ramp bicycle CPET-ESE. The acquisition protocol included left ventricular cardiac output, global longitudinal strain, E/e', peak oxygen consumption (VO₂ ), non-invasive arterial-venous oxygen content difference (AVO₂ diff) and lung ultrasound B-lines. There was a decline in peak VO₂ from controls (24.4 ± 3 mL/min/kg) to HFpEF-HT (15.2 ± 2 mL/min/kg), passing through HT (18.7 ± 2 mL/min/kg; P < 0.0001). HFpEF-HT displayed a lower peak cardiac output (9.8 ± 0.9 L/min) compared to HT (12.6 ± 1.0 L/min; P = 0.02) and controls (13.3 ± 1.0 L/min; P = 0.01). Peak AVO₂ diff was reduced in HFpEF-HT and HT (13.3 ± 2 and 13.5 ± 2 mL/dL vs. controls: 16.9 ± 2 mL/dL; P < 0.0001). A different left ventricular contractility was observed among groups, expressed as low-load global longitudinal strain (-16.8 ± 5% in HFpEF-HT, -18.2 ± 3% in HT, and 20.9 ± 3% in controls; P < 0.0001), and distribution of E/e' and B-lines [HFpEF-HT: 13.7 ± 3 and 16, interquartile range (IQR) 10-22; HT: 9.5 ± 2 and 8, IQR 4-10; controls: 6.2 ± 2 and 0, IQR 0-2; P < 0.0001].

CONCLUSIONS

Reduced peak VO₂ values in HT with and without HFpEF may be the result of decreased AVO₂ diff. CPET-ESE can also identify mild signs of left ventricular systo-diastolic dysfunction and pulmonary congestion, promoting advances in personalized therapy.

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.

Diastolic Dysfunction and Heart Failure With Preserved Ejection Fraction: Understanding Mechanisms by Using Noninvasive Methods

Research in the last decade has substantially advanced our understanding of the pathophysiology of heart failure with preserved ejection fraction (HFpEF). However, treatment options remain limited as clinical trials have largely failed to identify effective therapies. Part of this failure may be related to mechanistic heterogeneity. It is speculated that categorizing HFpEF patients based upon underlying pathophysiological phenotypes may represent the key next step in delivering the right therapies to the right patients. Echocardiography may provide valuable insight into both the pathophysiology and underlying phenotypes in HFpEF. Echocardiography also plays a key role in the evaluation of patients with unexplained dyspnea, where HFpEF is suspected but the diagnosis remains unknown. The combination of the E/e' ratio and right ventricular systolic pressure has recently been shown to add independent value to the diagnostic evaluation of patients suspected of having HFpEF. Finally, echocardiography enables identification of the different causes that mimic HFpEF but are treated differently, such as valvular heart disease, pericardial constriction, and high-output heart failure or infiltrative myopathies such as cardiac amyloid. This review summarizes the current understanding of the pathophysiology and phenotyping of HFpEF with particular attention to the role of echocardiography in this context.

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.

Pulse wave velocity and short-term outcome in patients requiring intravascular volume expansion: a pilot study

BACKGROUND

Fluid therapy has a pivotal role in the management of acutely ill patients. However, whether or not a patient can tolerate additional intravascular volume is controversial and optimal strategy is unknown. Carotid femoral pulse wave velocity (cfPWV) evaluates arterial stiffness.

OBJECTIVE

To determine whether cfPWV can predict the ability of patients to tolerate clinically indicated acute fluid expansion.

METHODS

50 consecutive patients requiring intravascular volume expansion were prospectively recruited in intensive care units. All subjects underwent transthoracic echocardiography, pulmonary ultrasound assessment, and a cfPWV study (S. Giovanni Bosco Hospital in Turin, Italy, between 2015 and 2016) at baseline and after 24 hours. Acute outcomes were registered at 24 hours ("soft" end points) and 30 days ('hard' end points: death, acute myocardial infarction, stroke, occurrence of atrial fibrillation, need for dialysis) after initial fluid therapy. Multivariate logistic regression was used to assess association of the initial cfPWV with outcomes.

RESULTS

cfPWV was significantly higher (10.6±3.6 vs 7.4±2.2 m/s, P<0.0001) in subjects who met the prespecified combined endpoints (hard or soft) than in those who did not. After adjustment for confounding factors, initial cfPWV was significantly and independently associated with the occurrence of hard events (OR=2.8 (95% CI 1.36 to 5.97), P=0.005; area under the receiver operating characteristic curve 84%). cfPWV of <9 m/s had a negative predictive value of 93%, excluding hard events associated with fluid expansion.

CONCLUSION

cfPWV appears to reflect the ability of the patient to tolerate an intravascular fluid expansion when clinically indicated. Increased cfPWV could help to identify subjects at greater risk of developing signs and symptoms of fluid overload.

Brachial pulse pressure in acute heart failure. Results of the Heart Failure Registry

Aims

To investigate the still uncertain independent prognostic impact of pulse pressure (PP) in acute heart failure (HF), in particular across the left ventricular ejection fraction (EF) phenotypes, and the potential contribution of PP in outlining the individual phenotypes.

Methods and results

We prospectively evaluated 1‐year death and rehospitalization in 4314 patients admitted for acute HF grouped by EF and stratified by their PP level on admission. In HF with reduced (< 40%) EF (HFrEF), the highest quartiles of PP had the lowest unadjusted [hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.61–0.98] and adjusted (HR 0.64 0.50–0.82) risk of 1 year all cause death compared to the lowest quartile. Its prognostic impact was partially mediated by systolic blood pressure (SBP). In HF with preserved (≥ 50%) EF (HFpEF), the intermediate quartile of PP showed the lowest 1 year all cause mortality in unadjusted (HR 0.598, CI 0.416–0.858) and adjusted (HR 0.55, 95% CI 0.388‐0.801) models with no relationship with SBP. In a receiver operating characteristic analysis, a combination of PP > 60 mmHg and SBP > 140 mmHg was associated to a preserved EF with a high performance value. No prognostic significance of PP was found in the HF with mid‐range EF subgroup.

Conclusions

In acute HFrEF, there is an almost linear inverse relation between mortality and PP, partly mediated by SBP. In HFpEF, a J‐shaped relationship between mortality and PP was present with a better prognosis at the nadir. A combination of PP > 60 mmHg with SBP > 140 mmHg may be clinically helpful as marker of a preserved left ventricular EF.

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.

Mild Coarctation of Aorta is an Independent Risk Factor for Exercise-Induced Hypertension

Exercise-induced hypertension is a predictor of cardiovascular events in patients with coarctation of aorta (COA). However, it is unclear whether mild COA diagnosis is an independent risk factor of exercise-induced hypertension. We hypothesized that for every unit increase in exercise, patients with COA (without hemodynamically significant coarctation) will have a higher rise in systolic blood pressure (SBP) compared with matched controls. One hundred forty-nine patients with COA (aortic coarctation peak velocity <2 m/s) who underwent exercise testing were matched 1:1 to controls using propensity score method based on age, sex, body mass index, hypertension diagnosis, and SBP at rest. We compared exercise-induced change in SBP between patients with COA and controls and also assessed the correlation between Doppler-derived aortic vascular function indices (effective arterial elastance index and total arterial compliance index) and exercise-induced changes in SBP. Compared with controls, patients with COA had a greater change in SBP per unit metabolic equivalent (β=2.86; 95% CI, 1.96–4.77 versus 1.07, 95% CI, −0.15 to 1.75; P =0.018) and per unit oxygen pulse (β=4.57; 95% CI, 2.97–7.12 versus 1.45, 95% CI, −0.79 to 2.09, P <0.001). There was a correlation between SBP peak −SBP rest and elastance index ( r =0.38, P =0.032) and between SBP peak −SBP rest and total arterial compliance index ( r =−0.51, P =0.001), suggesting an association between vascular dysfunction and exercise-induced BP changes. Patients with COA, without significant obstruction, had higher exercise-induced changes in SBP after adjustment for other risk factors for hypertension. Considering the already known prognostic importance of exercise-induced hypertension, the current study highlights the potential role of exercise testing for risk stratification of patients with mild COA.

Assessment and Implications of Right Ventricular Afterload in Tetralogy of Fallot

Patients with tetralogy of Fallot (TOF) have abnormal right ventricular (RV) afterload because of residual or recurrent outflow tract obstruction, often with abnormal pulmonary artery (PA) vascular function. The purpose of this study was to determine if RV afterload was independently associated with death and/or heart transplant in patients with TOF. This is a retrospective study of TOF patients that underwent cardiac catheterization for clinical indications at Mayo clinic between 1990 and 2015. Invasively measured RV systolic pressure (RVSP) was used to define RV afterload. To explore clinical utility for echocardiographic estimates of invasive data, correlations between invasive and Doppler-derived indices of RV afterload were examined. Among 266 patients with TOF (age 35 ± 14 years, TOF-pulmonary atresia 117 [44%]), RVSP was 72 ± 28 mm Hg, PA systolic pressure 45 ± 19 mm Hg, mean PA pressure 27 ± 10 mm Hg, pulmonary vascular resistance 4.2 ± 3.1 WU, and PA wedge pressure 14 ± 5 mm Hg. Over a mean follow up of 12.9 years, there were 35 deaths and 4 heart transplants. Invasively measured RVSP (hazard ratio 1.25, 95% confidence interval 1.12 to 1.37; p <0.001) and TOF-pulmonary atresia (hazard ratio 1.18, 95% confidence interval 1.08 to 1.41; p = 0.023) were independent risk factors for death and/or transplant. Doppler-derived RVSP was well-correlated with invasive RVSP (r = 0.92, p <0.001), and was also independently associated with the combined end point. RVSP, a composite measure of RV afterload, is independently prognostic in patients with TOF, and can be reliably assessed using Doppler echocardiography. Further study is required to test whether interventions to reduce RVSP can improve outcomes in patients with TOF.

Therapeutic Implications of Nitrite in Hypertension

Nitrite, an anion produced from the oxidative breakdown of nitric oxide (NO), has traditionally been viewed as an inert molecule. However, this dogma has been challenged with the findings that nitrite can be readily reduced to NO under pathological conditions, hence representing a physiologically relevant storage reservoir of NO either in the blood or tissues. Nitrite administration has been demonstrated to improve myocardial function in subjects with heart failure and to lower the blood pressure in hypertensive subjects. Thus, extensive amount of work has since been carried out to investigate the therapeutic potential of nitrite in treating cardiovascular diseases, especially hypertension. Studies done on several animal models of hypertension have demonstrated the efficacy of nitrite in preventing and ameliorating the pathological changes associated with the disease. This brief review of the current findings aims to re-evaluate the use of nitrite for the treatment of hypertension and in particular to highlight its role in improving endothelial function.

[Mechanisms of exercise intolerance in patients with heart failure and preserved ejection fraction. Part II: The role of right heart chambers, vascular system and skeletal muscles]

The main clinical manifestation of heart failure with preserved ejection fraction is poor exercise tolerance. In addi-tion to the dysfunction of the left heart chambers, which were presented in the first part of this review, many other disorders are involved in poor exercise tolerance in such patients: impairments of the right heart, vascular system and skeletal muscle. The second part of this review presents the mechanisms for the development of these disorders, as well as possible ways to correct them.

Ankle-brachial index and incident heart failure with reduced versus preserved ejection fraction: The Multi-Ethnic Study of Atherosclerosis

This study investigated the relationship between ankle-brachial index (ABI) and risk for heart failure with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). ABI has previously been associated with mortality, cardiovascular disease (CVD), and overall HF but the relationship between ABI and risk of HF stratified by EF has not been well characterized. We analyzed data from 6553 participants (53% female; mean age 62 ± 10 years) enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA) who were free of known clinical CVD/HF at baseline (2000-2002) and had baseline ABI measured. Participants were classified as low (≤ 0.90), borderline-low (0.91-1.00), normal (1.01-1.40), and high (> 1.40) ABI. Incident hospitalized HF was determined over a median follow-up of 14 years; we classified HF events (n = 321) as HFrEF with EF < 50% (n = 155, 54%) or HFpEF with EF ⩾ 50% (n = 133, 46%). Low ABI was associated with incident HFrEF (hazard ratio (HR): 2.02, 95% CI 1.19-3.40, p = 0.01) and had no significant association with HFpEF (HR: 0.67, 95% CI 0.30-1.48, p = 0.32). Borderline-low and high ABI were not significantly associated with HFrEF or HFpEF. Cubic spline analyses showed association with both low and high ABI for HFrEF and high ABI for HFpEF. A 1 SD lower ABI (for ABI < 1.1) was associated with incident HFrEF in multivariable analysis (HR: 1.27, 95% CI 1.05-1.54) but was not significant after additionally adjusting for interim myocardial infarction (HR: 1.21, 95% CI 0.99-1.48). Low ABI was associated with higher risk for incident HFrEF but not HFpEF in persons free of known CVD. Future studies of a larger size are needed for high ABI analyses.

Arterial Remodeling and Dysfunction in the ZSF1 Rat Model of Heart Failure With Preserved Ejection Fraction

BACKGROUND

The interplay between the stiffened heart and vessels has long been viewed as a core mechanism in heart failure with preserved ejection fraction, but the incremental vascular molecular remodeling mechanisms from systemic arterial hypertension to heart failure with preserved ejection fraction remain poorly investigated. Our aim was to characterize central arterial remodeling and dysfunction in ZSF1 obese rats and to compare it with hypertensive ZSF1 lean and healthy Wistar-Kyoto controls.

METHODS AND RESULTS

Twenty-week-old male ZSF1 obese (n=9), lean (n=9), and Wistar-Kyoto rats (n=9) underwent left ventricular pressure-volume loop evaluation and synchronous acquisition of ascending aortic flow and pressure. Aortic rings underwent functional evaluation, histology, and molecular biology studies. Although mean arterial pressure, characteristic aortic impedance, and reactivity to phenylephrine were similarly increased in hypertensive ZSF1 lean and obese, only ZSF1 obese showed impaired relaxation and upward-shifted end-diastolic pressure-volume relationships despite preserved systolic function indexes, denoting heart failure with preserved ejection fraction. ZSF1 obese phenotype further showed decreased aortic compliance, increased wave reflection, and impaired direct NO donor and endothelial-mediated vasodilation which were accompanied on structural and molecular grounds by aortic media thickening, higher collagen content and collagen/elastin ratio, increased fibronectin and α-5 integrin protein expression and upregulated TGF (transforming growth factor)-β and CTGF (connective tissue growth factor) levels.

CONCLUSIONS

Functional, molecular, and structural disturbances of central vessels and their potentially underlying pathways were newly characterized in experimental heart failure with preserved ejection fraction rendering the ZSF1 obese rat model suitable for preclinical testing.

Impact of Sex on Ventricular-Vascular Stiffness and Long-Term Outcomes in Heart Failure With Preserved Ejection Fraction: TOPCAT Trial Substudy

Background

Women have higher vascular stiffness with aging. The aim of this study was to characterize sex differences in vascular and ventricular structure and function, and to investigate the impact on the primary outcome in the TOPCAT trial (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial).

Methods and Results

Data from the Americas cohort of the TOPCAT trial were analyzed. Patients with echocardiography (n=654) were compared according to sex, and achievement of the primary end point (a composite of death from cardiovascular causes and heart failure hospitalization) assessed. Echocardiography revealed higher arterial, systolic, and diastolic ventricular elastance and worse ventricular‐vascular coupling in women. Women had better overall survival and heart failure hospitalization outcomes (hazard ratio 0.74, 95% CI 0.57–0.98, P=0.034), however, determinants of achievement of the primary outcome differed between the sexes. Pulse pressure was a key determinant of outcome in women (hazard ratio 1.04, 95% CI 1–1.09, P=0.034) whereas in men heart rate (hazard ratio 1.61, 95% CI 1.02–2.52 per 10 mm Hg increase, P=0.04) and B‐type natriuretic peptide (hazard ratio 1.01, 95% CI 1–1.02 per 10 ng/mL increase P=0.02) were associated with poorer outcome.

Conclusions

Outcomes in patients with heart failure with preserved ejection fraction appear to be differentially influenced by key physiological factors that vary according to sex. In women, ventricular‐vascular stiffening was the most significant determinant of outcome, whereas in men overall survival was influenced by heart rate and B‐type natriuretic peptide; this highlights key sex differences in the pathophysiology and outcomes of heart failure with preserved ejection fraction and warrants further exploration.

Clinical Trial Registration

URL: https://clinicaltrials.gov. Unique identifier: NCT00094302.

Heart Failure With Preserved Ejection Fraction: A Review of Cardiac and Noncardiac Pathophysiology

Heart failure with preserved ejection fraction (HFpEF) is one of the largest unmet clinical needs in 21st-century cardiology. It is a complex disorder resulting from the influence of several comorbidities on the endothelium. A derangement in nitric oxide bioavailability leads to an intricate web of physiological abnormalities in the heart, blood vessels, and other organs. In this review, we examine the contribution of cardiac and noncardiac factors to the development of HFpEF. We zoom in on recent insights on the role of comorbidities and microRNAs in HFpEF. Finally, we address the potential of exercise training, which is currently the only available therapy to improve aerobic capacity and quality of life in HFpEF patients. Unraveling the underlying mechanisms responsible for this improvement could lead to new biomarkers and therapeutic targets for HFpEF.

Heart Failure With Preserved Ejection Fraction In Perspective

Approximately half of the patients with signs and symptoms of heart failure have a left ventricular ejection fraction that is not markedly abnormal. Despite the historically initial surprise, heightened risks for heart failure specific major adverse events occur across the broad range of ejection fraction, including normal. The recognition of the magnitude of the problem of heart failure with preserved ejection fraction in the past 20 years has spurred an explosion of clinical investigation and growing intensity of informative outcome trials. This article addresses the historic development of this component of the heart failure syndrome, including the epidemiology, pathophysiology, and existing and planned therapeutic studies. Looking forward, more specific phenotyping and even genotyping of subpopulations should lead to improvements in outcomes from future trials.

Diastology for the clinician

Diastolic filling of the heart is a complex sequence of multiple inter-related events consisting of processes such as ventricular relaxation, erectile coronary effect, visco-elastic forces of the myocardium, ventricular interaction, myocardial stress strain relationships, pericardial restraint, passive filling, and atrial contraction. However, in order to understand diastolic filling from a clinical aspect, a simplified foundation can be used which divides the cardiac cycle into contraction, relaxation, passive filling, and filling at atrial contraction. The mitral flow velocity curves are representative of the relative driving pressure between left atrium and left ventricle and allow one to grade the progression of diastolic dysfunction which occurs in disease states. Doppler tissue imaging is necessary as a surrogate of ventricular relaxation to further determine the stages of diastolic dysfunction in patients with preserved ejection fraction. These Doppler flow velocity curves can be applied to understanding diastolic filling of the heart in patients with both reduced ejection fraction and preserved ejection fraction.

Assessment of Right Ventricular-Pulmonary Arterial Coupling in Chronic Pulmonary Regurgitation

BACKGROUND

We hypothesized that noninvasively measured right ventricular (RV) to pulmonary arterial (RV-PA) coupling would be abnormal in chronic pulmonary regurgitation (PR) even in the setting of normal RV ejection fraction, and that RV-PA coupling indices would have a better correlation with peak oxygen consumption (VO₂) compared with RV systolic indices alone.

METHODS

This was a retrospective study of 129 adults (repaired tetralogy of Fallot [TOF] n = 84 and valvular pulmonic stenosis [VPS] with previous intervention n = 45) with ≥ moderate native PR and RV ejection fraction > 50%. The 84 TOF patients were propensity matched with 84 patients with normal echocardiogram (control); age 28 ± 7 years and male sex n = 39 (46%). RV-PA coupling was measured according to fractional area change (FAC)/RV systolic pressure (RVSP) and tricuspid annular plane systolic excursion (TAPSE)/RVSP.

RESULTS

RV systolic function indices were similar between TOF and control groups (FAC 43 ± 6% vs 41 ± 5% [P = 0.164] and TAPSE 22 ± 5 mm vs 24 ± 6 mm [P = 0.263]). However, RV-PA coupling was lower in the TOF group (FAC/RVSP 1.10 ± 0.29 vs 1.48 ± 0.22 [P < 0.001]; TAPSE/RVSP 0.51 ± 0.15 vs 0.78 ± 0.11 [P < 0.001]) because of higher RV afterload (RVSP 42 ± 3 mm Hg vs 31 ± 3 mm Hg [P = 0.012]). FAC/RVSP (r = 0.61; P < 0.001) and TAPSE/RVSP (r = 0.69; P < 0.001) correlated with peak VO₂ especially in the patients with impaired exercise capacity whereas FAC and TAPSE were independent of peak VO₂. Similar comparisons between VPS and control groups showed no difference in TAPSE and FAC between groups, but lower FAC/RVSP and TAPSE/RVSP in the VPS group.

CONCLUSIONS

There is abnormal RV-PA coupling in chronic PR, and noninvasively measured RV-PA coupling might potentially be prognostic because of its correlation with exercise capacity.

Central and Peripheral Determinants of Exercise Capacity in Heart Failure Patients With Preserved Ejection Fraction

OBJECTIVES

This study sought to discern which central (e.g., heart rate, stroke volume [SV], filling pressure) and peripheral factors (e.g., oxygen use by skeletal muscle, body mass index [BMI]) during exercise were most strongly associated with the presence of heart failure and preserved ejection fraction (HFpEF) as compared with healthy control subjects exercising at the same workload.

BACKGROUND

The underlying mechanisms limiting exercise capacity in patients with HFpEF are not fully understood.

METHODS

In patients with HFpEF (n = 108), the hemodynamic response at peak exercise was measured using right-sided heart catheterization and was compared with that in healthy control subjects (n = 42) at matched workloads to reveal hemodynamic differences that were not attributable to the workload performed. The patients studied were prospectively included in the REDUCE-LAP HF (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure) trials and HemReX (Effect of Age on the Hemodynamic Response During Rest and Exercise in Healthy Humans) study. Univariable and multivariable logistic regression models were used to analyze variables associated with HFpEF versus control subjects.

RESULTS

Compared with healthy control subjects, pulmonary capillary wedge pressure (PCWP) and SV were the only independent hemodynamic variables that were associated with HFpEF, a finding explaining 66% (p < 0.0001) of the difference between the groups. When relevant baseline characteristics were added to the base model, only BMI emerged as an additional independent variable, in total explaining of 90% of the differences between groups (p < 0.0001): PCWP (47%), BMI (31%), and SV (12%).

CONCLUSIONS

The study identified 3 key variables (PCWP, BMI, and SV) that independently correlate with the presence of patients with HFpEF compared with healthy control subjects exercising at the same workload. Therapies that decrease left-sided heart filling pressures could improve exercise capacity and possibly prognosis.

Heart Failure With Preserved Ejection Fraction - Time for a Paradigm Shift Beyond Diastolic Function

At present, heart failure with preserved ejection fraction (HFpEF) is a commonly accepted condition in HF patients. In contrast to HF with reduced EF (HFrEF), HFpEF is strongly associated with aging, and vascular, metabolic, neurohormonal, and systemic inflammatory comorbidities. Two major hypotheses explain the pathophysiology of HFpEF (stages C,D in the American College of Cardiology Foundation/American Heart Association HF staging system): (1) impaired active relaxation and increased passive stiffness of the left ventricular (LV) myocardium during diastole (left atrial [LA]-LV coupling); and (2) LV and arterial stiffening during systole (LV-arterial coupling). Cardiac structural and functional abnormalities can be evaluated using non-invasive measures, such as 2-D, flow velocity Doppler, and tissue Doppler echocardiography, to estimate LV filling pressure and afterload mismatch. The clinical application of 2-D speckle-tracking echocardiography (2D-STE) is feasible for earlier diagnosis of functional abnormalities of the LA, LV, and elastic arteries in asymptomatic patients with cardiovascular risk factors (stages A,B). The goal of this review is to highlight the role of 2D-STE to detect impairment of LA-LV-arterial coupling beyond diastolic function earlier, because it may provide important information on the pathophysiology and prevention of HFpEF.

Cardiac effects of 6 months' dietary nitrate and spironolactone in patients with hypertension and with/at risk of type 2 diabetes, in the factorial design, double-blind, randomized controlled VaSera trial

AIMS

The aims of the present study were to explore whether a long-term intervention with dietary nitrate [(NO₃ ^- ), a potential tolerance-free source of beneficial vasoactive nitric oxide] and spironolactone (to oppose aldosterone's potential deleterious cardiovascular effects) improve cardiac structure/function, independently of blood pressure (BP), in patients with/at risk of type 2 diabetes (a population at risk of heart failure).

METHODS

A subsample of participants in our double-blind, randomized, factorial-design intervention (VaSera) trial of active beetroot juice as a nitrate source (≤11.2 mmol) or placebo (nitrate depleted) beetroot juice, and either ≤50 mg spironolactone or ≤16 mg doxazosin (control), had transthoracic cardiac ultrasounds at baseline (n = 105), and at 3 months and 6 months (n = 87) after the start of the intervention. Analysis was by modified intent-to-treat.

RESULTS

Nitrate-containing juice (n = 40) decreased left ventricular (LV) end-diastolic volume {-6.3 [95% confidence interval (CI) -11.1, -1.6] ml} and end-systolic volume [-3.2 (95% CI -5.9, -0.5) ml], and increased end-diastolic mass/volume ratio [+0.04 (95% CI 0.00, 0.07)], relative to placebo juice (n = 47). Spironolactone (n = 44) reduced relative wall thickness compared with doxazosin (n = 43) [-0.01 (95% CI -0.02, -0.00)]. Although spironolactone reduced LV mass index relative to baseline [-1.48 (95% CI -2.08, -0.88) g m^-2.7 ], there was no difference vs. doxazosin [-0.85 (95% CI -1.76, 0.05) g m^-2.7 ]. Spironolactone also decreased the E/A ratio [-0.12 (95% CI -0.19, -0.04)] and increased S' (a tissue-Doppler systolic function index) by 0.52 (95% CI 0.05, 1.0) cm s^-1 . BP did not differ between the juices, or between the drugs.

CONCLUSIONS

Six months' dietary nitrate decreased LV volumes ~5%, representing new, sustained, BP-independent benefits on cardiac structure, extending mechanisms characterized in preclinical models of heart failure. Spironolactone's effects on cardiac remodelling and systolic-diastolic function, although confirmatory, were independent of BP.

Effect of Inorganic Nitrite vs Placebo on Exercise Capacity Among Patients With Heart Failure With Preserved Ejection Fraction: The INDIE-HFpEF Randomized Clinical Trial

IMPORTANCE

There are few effective treatments for heart failure with preserved ejection fraction (HFpEF). Short-term administration of inorganic nitrite or nitrate preparations has been shown to enhance nitric oxide signaling, which may improve aerobic capacity in HFpEF.

OBJECTIVE

To determine the effect of 4 weeks' administration of inhaled, nebulized inorganic nitrite on exercise capacity in HFpEF.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, double-blind, placebo-controlled, 2-treatment, crossover trial of 105 patients with HFpEF. Participants were enrolled from July 22, 2016, to September 12, 2017, at 17 US sites, with final date of follow-up of January 2, 2018.

INTERVENTIONS

Inorganic nitrite or placebo administered via micronebulizer device. During each 6-week phase of the crossover study, participants received no study drug for 2 weeks (baseline/washout) followed by study drug (nitrite or placebo) at 46 mg 3 times a day for 1 week followed by 80 mg 3 times a day for 3 weeks.

MAIN OUTCOMES AND MEASURES

The primary end point was peak oxygen consumption (mL/kg/min). Secondary end points included daily activity levels assessed by accelerometry, health status as assessed by the Kansas City Cardiomyopathy Questionnaire (score range, 0-100, with higher scores reflecting better quality of life), functional class, cardiac filling pressures assessed by echocardiography, N-terminal fragment of the prohormone brain natriuretic peptide levels, other exercise indices, adverse events, and tolerability. Outcomes were assessed after treatment for 4 weeks.

RESULTS

Among 105 patients who were randomized (median age, 68 years; 56% women), 98 (93%) completed the trial. During the nitrite phase, there was no significant difference in mean peak oxygen consumption as compared with the placebo phase (13.5 vs 13.7 mL/kg/min; difference, -0.20 [95% CI, -0.56 to 0.16]; P = .27). There were no significant between-treatment phase differences in daily activity levels (5497 vs 5503 accelerometry units; difference, -15 [95% CI, -264 to 234]; P = .91), Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (62.6 vs 61.9; difference, 1.1 [95% CI, -1.4 to 3.5]; P = .39), functional class (2.5 vs 2.5; difference, 0.1 [95% CI, -0.1 to 0.2]; P = .43), echocardiographic E/e' ratio (16.4 vs 16.6; difference, 0.1 [95% CI, -1.2 to 1.3]; P = .93), or N-terminal fragment of the prohormone brain natriuretic peptide levels (520 vs 533 pg/mL; difference, 11 [95% CI, -53 to 75]; P = .74). Worsening heart failure occurred in 3 participants (2.9%) during the nitrite phase and 8 (7.6%) during the placebo phase.

CONCLUSIONS AND RELEVANCE

Among patients with HFpEF, administration of inhaled inorganic nitrite for 4 weeks, compared with placebo, did not result in significant improvement in exercise capacity.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02742129.

Mechanisms underlying blood pressure reduction by dietary inorganic nitrate

Nitric oxide (NO) importantly contributes to cardiovascular homeostasis by regulating blood flow and maintaining endothelial integrity. Conversely, reduced NO bioavailability is a central feature during natural ageing and in many cardiovascular disorders, including hypertension. The inorganic anions nitrate and nitrite are endogenously formed after oxidation of NO synthase (NOS)-derived NO and are also present in our daily diet. Knowledge accumulated over the past two decades has demonstrated that these anions can be recycled back to NO and other bioactive nitrogen oxides via serial reductions that involve oral commensal bacteria and various enzymatic systems. Intake of inorganic nitrate, which is predominantly found in green leafy vegetables and beets, has a variety of favourable cardiovascular effects. As hypertension is a major risk factor of morbidity and mortality worldwide, much attention has been paid to the blood pressure reducing effect of inorganic nitrate. Here, we describe how dietary nitrate, via stimulation of the nitrate-nitrite-NO pathway, affects various organ systems and discuss underlying mechanisms that may contribute to the observed blood pressure-lowering effect.

Exercise unmasks distinct pathophysiologic features in heart failure with preserved ejection fraction and pulmonary vascular disease

Aims

Pulmonary hypertension (PH) and pulmonary vascular disease (PVD) are common and associated with adverse outcomes in heart failure with preserved ejection fraction (HFpEF). Little is known about the impact of PVD on the pathophysiology of exercise intolerance.

Methods and results

Heart failure with preserved ejection fraction patients (n = 161) with elevated pulmonary capillary wedge pressure (≥15 mmHg) at rest were classified into three groups: non-PH-HFpEF (n = 21); PH but no PVD (isolated post-capillary PH, IpcPH; n = 95); and PH with PVD (combined post- and pre-capillary PH, CpcPH; n = 45). At rest, CpcPH-HFpEF patients had more right ventricular (RV) dysfunction and lower pulmonary arterial (PA) compliance compared to all other groups. While right atrial pressure (RAP) and left ventricular transmural pressure (LVTMP) were similar in HFpEF with and without PH or PVD at rest, CpcPH-HFpEF patients demonstrated greater increase in RAP, enhanced ventricular interdependence, and paradoxical reduction in LVTMP during exercise, differing from all other groups (P < 0.05). Lower PA compliance was correlated with greater increase in RAP with exercise. During exercise, CpcPH-HFpEF patients displayed an inability to enhance cardiac output, reduction in forward stroke volume, and blunted augmentation in RV systolic performance, changes that were coupled with marked limitation in aerobic capacity.

Conclusion

Heart failure with preserved ejection fraction patients with PVD demonstrate unique haemodynamic limitations during exercise that constrain aerobic capacity, including impaired recruitment of LV preload due to excessive right heart congestion and blunted RV systolic reserve. Interventions targeted to this distinct pathophysiology require testing in patients with HFpEF and PVD.

Benefits of exercise training on cardiovascular dysfunction: molecular and integrative

Exercise training has been shown to ameliorate a wide variety of cardiovascular disorders. The mechanisms by which long-term benefits of exercise training are mediated remains incomplete, despite intense research in this area. Exactly how the act of chronic exercise improves function in every tissue is unknown, but many of the cellular, molecular, and genetic mechanisms are becoming progressively clearer. This "Perspectives" article reviews the contributions of 15 articles published in the American Journal of Physiology-Heart and Circulatory Physiology in response to a Call for Papers in this area. Here, we summarize the contributions of these studies at the cardiac, vascular, immune, and molecular levels. We discuss the translational benefit of these studies and conclude that the beneficial effects of exercise training in cardiovascular disease is due to a large interplay of cellular and molecular mediators in the heart and peripheral vasculature as well as changes in neural elements that regulate blood pressure and blood flow. Readers are encouraged to evaluate and learn from this collection of novel studies.

Myocardial Injury and Cardiac Reserve in Patients With Heart Failure and Preserved Ejection Fraction

BACKGROUND

Cardiac reserve is depressed in patients with heart failure and preserved ejection fraction (HFpEF). The mechanisms causing this are poorly understood.

OBJECTIVES

The authors hypothesized that myocardial injury might contribute to the hemodynamic derangements and cardiac reserve limitations that are present in HFpEF. Markers of cardiomyocyte injury, central hemodynamics, ventricular function, and determinants of cardiac oxygen supply-demand balance were measured.

METHODS

Subjects with HFpEF (n = 38) and control subjects without heart failure (n = 20) underwent cardiac catheterization, echocardiography, and expired gas analysis at rest and during exercise. Central venous blood was sampled to measure plasma high-sensitivity troponin T levels as an index of cardiomyocyte injury.

RESULTS

Compared with control subjects, troponins were more than 2-fold higher in subjects with HFpEF at rest and during exercise (p < 0.0001). Troponin levels were directly correlated with left ventricular (LV) filling pressures (r = 0.52; p < 0.0001) and diastolic dysfunction (r = -0.43; p = 0.002). Although myocardial oxygen demand was similar, myocardial oxygen supply was depressed in HFpEF, particularly during exercise (coronary perfusion pressure-time integral; 44 ± 9 mm Hg × s × min-1 × l × dl-1 vs. 30 ± 9 mm Hg × s × min-1 × l × dl-1; p < 0.0001), and reduced indices of supply were correlated with greater myocyte injury during exercise (r = -0.44; p = 0.0008). Elevation in troponin with exercise was directly correlated with an inability to augment LV diastolic (r = -0.40; p = 0.02) and systolic reserve (r = -0.57; p = 0.0003), greater increases in LV filling pressures (r = 0.55; p < 0.0001), blunted cardiac output response (r = -0.44; p = 0.002), and more severely depressed aerobic capacity in HFpEF.

CONCLUSIONS

Limitations in LV functional reserve and the hemodynamic derangements that develop secondary to these limitations during exercise in HFpEF are correlated with the severity of cardiac injury, assessed by plasma levels of troponin T. Further study is warranted to determine the mechanisms causing myocyte injury in HFpEF and the potential role of ischemia, and to identify and test novel interventions targeted to these mechanisms. (EXEC [Study of Exercise and Heart Function in Patients With Heart Failure and Pulmonary Vascular Disease]; NCT01418248).

Adiposity, body composition and ventricular-arterial stiffness in the elderly: the Atherosclerosis Risk in Communities Study

AIM

Weight gain appears to accelerate age-related ventricular-arterial stiffening, which has been implicated in the development of heart failure (HF), but it is unclear whether body fat accumulation underpins this association. We evaluated the relationship of adiposity, using measures of body composition, with ventricular-arterial stiffness among the elderly in the community.

METHODS AND RESULTS

Adiposity was accessed through body mass index (BMI), waist circumference, and body fat percentage. We studied the association of these measures with carotid-femoral pulse wave velocity (cfPWV), arterial elastance index (EaI), left ventricular (LV) end-systolic elastance index (EesI) and LV end-diastolic elastance index (EedI) in 5520 community-based, elderly Atherosclerosis Risk in Communities (ARIC) Study participants, who underwent echocardiography between 2011 and 2013. BMI and waist circumference were directly associated with EaI, EedI and EesI even after adjusting for age, sex, race, hypertension, diabetes mellitus, heart rate, prevalent coronary heart disease and HF. After further adjustment for BMI, body fat percentage demonstrated significant independent linear relationships with EaI [standardized beta coefficient (β)=0.17, P<0.001], EesI (β=0.08, P=0.003) and EedI (β=0.20, P<0.001), and significant non-linear relationships with cfPWV (P=0.033).

CONCLUSION

In this biracial community-based cohort, increased adiposity was associated with increased ventricular-arterial stiffness among the elderly and suggests a potential mechanism by which obesity might contribute to the development of HF.

Hospitalisation in Patients With Heart Failure With Preserved Ejection Fraction

Heart failure is highly prevalent with more than 50% of cases being patients with a preserved ejection fraction (HFPEF), a figure that is projected to increase due to the changing risk factor landscape, in particular the ageing population. Overall mortality is similar to patients with heart failure with reduced ejection fraction (HFREF), as are the rates of hospitalisation. Patients with HFPEF have more comorbid conditions with fewer therapeutic options available. In this review, we explore the epidemiology of hospitalisation of HFPEF, the impact of current treatment modalities, and the potential of future therapies.