Epidemiology, Pathophysiology, Diagnosis, and Therapy of Heart Failure With Preserved Ejection Fraction in Japan.

Heart failure (HF) with preserved ejection fraction (HFpEF) is a global health care problem, with diagnostic difficulty, limited treatment options and high morbidity and mortality rates. The prevalence of HFpEF is increasing because of the aging population and the increasing burden of cardiac and metabolic comorbidities, such as systemic hypertension, diabetes, chronic kidney disease, and obesity. The knowledge base is derived primarily from the United States and Europe, and data from Asian countries, including Japan, remain limited. Given that phenotypic differences may exist between Japanese and Western patients with HFpEF, careful characterization may hold promise to deliver new therapy specific to the Japanese population. In this review, we summarize the current knowledge regarding the epidemiology, pathophysiology and diagnosis of and the potential therapies for HFpEF in Japan.

Heart failure with preserved ejection fraction in patients with normal natriuretic peptide levels is associated with increased morbidity and mortality.

BACKGROUND: A substantial proportion of patients with heart failure (HF) with preserved ejection fraction (HFpEF) present with normal natriuretic peptide (NP) levels. The pathophysiology and natural history for this phenotype remain unclear. METHODS AND RESULTS: Consecutive subjects undergoing invasive cardiopulmonary exercise testing for unexplained dyspnoea at Mayo Clinic in 2006-18 were studied. Heart failure with preserved ejection fraction was defined as a pulmonary arterial wedge pressure (PAWP) ≥15 mmHg (rest) or ≥25 mmHg (exercise). Patients with HFpEF and normal NP [N-terminal of the pro-hormone B-type natriuretic peptide (NT-proBNP) < 125 ng/L] were compared with HFpEF with high NP (NT-proBNP ≥ 125 ng/L) and controls with normal haemodynamics. Patients with HFpEF and normal (n = 157) vs. high NP (n = 263) were younger, yet older than controls (n = 161), with an intermediate comorbidity profile. Normal NP HFpEF was associated with more left ventricular hypertrophy and worse diastolic function compared with controls, but better diastolic function, lower left atrial volumes, superior right ventricular function, and less mitral/tricuspid regurgitation compared with high NP HFpEF. Cardiac output (CO) reserve with exercise was preserved in normal NP HFpEF [101% predicted, interquartile range (IQR): 75-124%], but this was achieved only at the cost of higher left ventricular transmural pressure (LVTMP) (14 ± 6 mmHg vs. 7 ± 4 mmHg in controls, P < 0.001). In contrast, CO reserve was decreased in high NP HFpEF (85% predicted, IQR: 59-109%), with lower LVTMP (10 ± 8 mmHg) compared with normal NP HFpEF (P < 0.001), despite similar PAWP. Patients with high NP HFpEF displayed the highest event rates, but normal NP HFpEF still had 2.7-fold higher risk for mortality or HF readmissions compared with controls (hazard ratio: 2.74, 95% confidence interval: 1.02-7.32) after adjusting for age, sex, and body mass index. CONCLUSION: Patients with HFpEF and normal NP display mild diastolic dysfunction and preserved CO reserve during exercise, despite marked elevation in filling pressures. While clinical outcomes are not as poor compared with patients with high NP, patients with normal NP HFpEF exhibit increased risk of death or HF readmissions compared with patients without HF, emphasizing the importance of this phenotype.

Pulmonary vascular disease in pulmonary hypertension due to left heart disease: pathophysiologic implications.

AIMS: Pulmonary hypertension (PH) and pulmonary vascular disease (PVD) are common and associated with adverse outcomes in left heart disease (LHD). This study sought to characterize the pathophysiology of PVD across the spectrum of PH in LHD. METHODS AND RESULTS: Patients with PH-LHD [mean pulmonary artery (PA) pressure >20 mmHg and PA wedge pressure (PAWP) ≥15 mmHg] and controls free of PH or LHD underwent invasive haemodynamic exercise testing with simultaneous echocardiography, expired air and blood gas analysis, and lung ultrasound in a prospective study. Patients with PH-LHD were divided into isolated post-capillary PH (IpcPH) and PVD [combined post- and pre-capillary PH (CpcPH)] based upon pulmonary vascular resistance (PVR <3.0 or ≥3.0 WU). As compared with controls (n = 69) and IpcPH-LHD (n = 55), participants with CpcPH-LHD (n = 40) displayed poorer left atrial function and more severe right ventricular (RV) dysfunction at rest. With exercise, patients with CpcPH-LHD displayed similar PAWP to IpcPH-LHD, but more severe RV-PA uncoupling, greater ventricular interaction, and more severe impairments in cardiac output, O2 delivery, and peak O2 consumption. Despite higher PVR, participants with CpcPH developed more severe lung congestion compared with both IpcPH-LHD and controls, which was associated lower arterial O2 tension, reduced alveolar ventilation, decreased pulmonary O2 diffusion, and greater ventilation-perfusion mismatch. CONCLUSIONS: Pulmonary vascular disease in LHD is associated with a distinct pathophysiologic signature marked by greater exercise-induced lung congestion, arterial hypoxaemia, RV-PA uncoupling, ventricular interdependence, and impairment in O2 delivery, impairing aerobic capacity. Further study is required to identify novel treatments targeting the pulmonary vasculature in PH-LHD.

Urinary FABP1 is a biomarker for impaired proximal tubular protein reabsorption and is synergistically enhanced by concurrent liver injury.

Urinary fatty acid binding protein 1 (FABP1, also known as liver-type FABP) has been implicated as a biomarker of acute kidney injury (AKI) in humans. However, the precise biological mechanisms underlying its elevation remain elusive. Here, we show that urinary FABP1 primarily reflects impaired protein reabsorption in proximal tubule epithelial cells (PTECs). Bilateral nephrectomy resulted in a marked increase in serum FABP1 levels, suggesting that the kidney is an essential organ for removing serum FABP1. Injected recombinant FABP1 was filtered through the glomeruli and robustly reabsorbed via the apical membrane of PTECs. Urinary FABP1 was significantly elevated in mice devoid of megalin, a giant endocytic receptor for protein reabsorption. Elevation of urinary FABP1 was also observed in patients with Dent disease, a rare genetic disease characterized by defective megalin function in PTECs. Urinary FABP1 levels were exponentially increased following acetaminophen overdose, with both nephrotoxicity and hepatotoxicity observed. FABP1-deficient mice with liver-specific overexpression of FABP1 showed a massive increase in urinary FABP1 levels upon acetaminophen injection, indicating that urinary FABP1 is liver-derived. Lastly, we employed transgenic mice expressing diphtheria toxin receptor (DT-R) either in a hepatocyte- or in a PTEC-specific manner, or both. Upon administration of diphtheria toxin (DT), massive excretion of urinary FABP1 was induced in mice with both kidney and liver injury, while mice with either injury type showed marginal excretion. Collectively, our data demonstrated that intact PTECs have a considerable capacity to reabsorb liver-derived FABP1 through a megalin-mediated mechanism. Thus, urinary FABP1, which is synergistically enhanced by concurrent liver injury, is a biomarker for impaired protein reabsorption in AKI. These findings address the use of urinary FABP1 as a biomarker of histologically injured PTECs that secrete FABP1 into primary urine, and suggest the use of this biomarker to simultaneously monitor impaired tubular reabsorption and liver function. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Pathophysiologic importance of visceral adipose tissue in women with heart failure and preserved ejection fraction.

AIMS: Central obesity is a major risk factor for heart failure with preserved ejection fraction (HFpEF), particularly in women, but the mechanisms remain unclear. We hypothesized that sex-specific differences in visceral adipose tissue (VAT) content would differentially relate to haemodynamic severity of HFpEF in women and men. METHODS AND RESULTS: Abdominal computed tomography (CT) and invasive haemodynamic exercise testing were performed in 105 subjects with HFpEF (63 women) and 105 age-, sex-, and body mass index-matched controls. Visceral adipose tissue area was quantified by CT. As compared with control women, VAT area was 34% higher in women with HFpEF (186 ± 112 vs. 139 ± 72 cm2, P = 0.006), while VAT area was not significantly different in men with or without HFpEF (294 ± 158 vs. 252 ± 92 cm2, P = 0.1). During exercise, pulmonary capillary wedge pressure (PCWP) increased markedly and to similar extent in both men and women with HFpEF. Women with increased VAT area displayed 33% higher PCWP during exercise compared with women with normal VAT area (28 ± 10 vs. 21 ± 10 mmHg, P = 0.001), whereas exercise PCWP was similar in men with or without excess VAT (24 ± 9 vs. 25 ± 6, P = 0.89). In women, each 100 cm2 increase in VAT area was associated with a 4.0 mmHg higher PCWP (95% CI 2.1, 6.0 mmHg; P < 0.0001), but there was no such relationship in men (interaction P = 0.009). CONCLUSIONS: These data suggest that accumulation of excess VAT plays a distinct and important role in the pathophysiology of HFpEF preferentially in women. Further research is needed to better understand the mechanisms and treatment implications for visceral fat in HFpEF.

Impact of Right Atrial Remodeling in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Few studies have investigated right atrial (RA) remodeling in heart failure (HF) with preserved ejection fraction (HFpEF). This study sought to characterize the RA remodeling in HFpEF and to determine its prognostic significance. METHODS AND RESULTS: Patients with HFpEF were classified based on the presence of RA enlargement (RA volume index >39 mL/m2 in men and >33 mL/m2 in women). Compared with patients with normal RA size (n = 234), patients with RA dilation (n = 67) showed a higher prevalence of atrial fibrillation (AF), worse right ventricular systolic function, more severe pulmonary hypertension, and a greater prevalence of mild tricuspid regurgitation, as well as impaired RA reservoir function, with increased hepatobiliary enzyme levels. AF was strongly associated with the presence of RA dilation (odds ratio [OR] 10.2, 95% confidence interval [CI] 4.00-26.1 in current AF vs no AF and odds ratio 3.38, 95% CI 1.26-9.07, earlier AF vs no AF). Patients with RA dilation had more than a two-fold increased risk of composite outcomes of all-cause mortality or HF hospitalization (adjusted hazard ratio 2.01, 95% CI 1.09-3.70, P = .02). The presence of RA dilation also displayed an additive prognostic value over left atrial dilation alone. CONCLUSIONS: These data demonstrate that HFpEF with RA remodeling is associated with distinct echocardiographic features characterizing advanced right heart dysfunction with an increased risk of adverse outcomes.

Salutary Acute Effects of Exercise on Central Hemodynamics in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: A warmup period of priming exercise has been shown to improve peripheral oxygen transport in older adults. We sought to determine the acute effects of priming exercise on central hemodynamics at rest and during a repeat exercise in heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: This is a post hoc analysis from 3 studies. Patients with HFpEF (n = 42) underwent cardiac catheterization with simultaneous expired gas analysis at rest and during exercise (20 W for 5 minutes, priming exercise). Measurements were then repeated at rest and during a second bout of exercise at a 20-W workload (second exercise). During the priming exercise, patients with HFpEF displayed dramatic increases in biventricular filling pressures and exercise-induced pulmonary hypertension. After the priming exercise at rest, biventricular filling pressures and pulmonary artery (PA) pressures were lower and lung tidal volume was increased. During the second bout of exercise, biventricular filling (PA wedge pressure, 29 ± 8 mm Hg at second exercise vs 32 ± 7 mm Hg at first exercise, P = .0003) and PA pressures were lower, and PA compliance increased. CONCLUSIONS: This study shows that short duration, submaximal priming exercise attenuates the pathologic increases in filling pressures, improving pulmonary vascular hemodynamics at rest and during repeat exercise in patients with HFpEF.

Pulmonary Vascular Alterations on Computed Tomography Imaging and Outcomes in Heart Failure With Preserved Ejection Fraction: a Preliminary Data.

BACKGROUND: Pulmonary vascular disease may play an important role in the pathophysiology of heart failure (HF) with preserved ejection fraction (HFpEF). However, no study has demonstrated noninvasive quantification of pulmonary vascular alterations in HFpEF. This study sought to determine the association between pulmonary vascular alterations quantified by chest computed tomography scan and clinical outcomes in HFpEF. METHODS AND RESULTS: Pulmonary vascular alterations were quantified in 151 patients with HFpEF who underwent noncontrast chest computed tomography scan by measuring the percentage of total cross-sectional area (CSA) of pulmonary vessels less than 5 mm2 to the total lung area (%CSA<5). We divided the patients by the median value of %CSA<5 (=1.45%) and examined the association between %CSA<5 and a composite outcome of all-cause mortality or HF hospitalization. During a median follow-up of 17.3 months, there were 44 (29%) composite outcomes. Event rates were significantly higher in patients with higher %CSA<5 than those with lower %CSA<5 (log-rank P = .02). %CSA<5 was associated with an increased risk of the outcome (hazard ratio per 1.0% increment, 1.46; 95% confidence interval 1.06-1.98; P = .02) in an unadjusted Cox model, and was independently and incrementally associated with the outcome over age, the presence of atrial fibrillation, E/e' ratio, and estimated pulmonary artery systolic pressure (global χ2 17.3 vs 11.5, P = .02). CONCLUSIONS: A higher %CSA<5 was associated with an increased risk of all-cause mortality or HF hospitalization in patients with HFpEF, with an incremental prognostic value over age, atrial fibrillation, E/e' ratio, and pulmonary artery systolic pressure.

The ß-Adrenergic Agonist Albuterol Improves Pulmonary Vascular Reserve in Heart Failure With Preserved Ejection Fraction.

RATIONALE: Pulmonary vascular resistance fails to decrease appropriately during exercise in patients with heart failure with preserved ejection fraction (HFpEF). Interventions that enhance pulmonary vasodilation might be beneficial in this cohort but could also worsen left atrial hypertension, exacerbating lung congestion. Intravenous ß-agonists reduce pulmonary vascular resistance but are not suitable for chronic use. OBJECTIVE: We hypothesized that the inhaled ß-adrenergic agonist albuterol would improve pulmonary vasodilation during exercise in patients with HFpEF, without increasing left heart filling pressures. METHODS AND RESULTS: We performed a randomized, double-blind, placebo-controlled trial testing the effects of inhaled albuterol on resting and exercise hemodynamics in subjects with HFpEF using high-fidelity micromanometer catheters and expired gas analysis. The primary end point was pulmonary vascular resistance during exercise. Subjects with HFpEF (n=30) underwent resting and exercise hemodynamic assessment and were then randomized 1:1 to inhaled, nebulized albuterol or placebo. Rest and exercise hemodynamic testing was then repeated. Albuterol improved the primary end point of exercise pulmonary vascular resistance as compared with placebo (-0.6±0.5 versus +0.1±0.7 WU; P=0.003). Albuterol enhanced cardiac output reserve and right ventricular pulmonary artery coupling, reduced right atrial and pulmonary artery pressures, improved pulmonary artery compliance, and enhanced left ventricular transmural distending pressure (all P <0.01), with no increase in pulmonary capillary hydrostatic pressures. CONCLUSIONS: Albuterol improves pulmonary vascular reserve in patients with HFpEF without worsening left heart congestion. Further study is warranted to evaluate the chronic efficacy of ß-agonists in HFpEF and other forms of pulmonary hypertension. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT02885636.

DPP-4 inhibitor induces FGF21 expression via sirtuin 1 signaling and improves myocardial energy metabolism.

Dipeptidyl peptidase-4 (DPP-4) inhibitors are widely used incretin-based therapy for the treatment of type 2 diabetes. We investigated the cardioprotective effect of a DPP-4 inhibitor, vildagliptin (vilda), on myocardial metabolism and cardiac performance under pressure overload. Mice were treated with either vehicle or vilda, followed by transverse aortic constriction (TAC). After 3 weeks of TAC, cardiac hypertrophy and impairment of systolic function were attenuated in vilda-treated mice. Pressure-volume analysis showed that vilda treatment significantly improved left-ventricular contractile efficiency in TAC heart. Myocardial energy substrate analysis showed that vilda treatment significantly increased glucose uptake as well as fatty acid uptake. Fibroblast growth factor 21 (FGF21), a peptide involved in the regulation of energy metabolism, increased in TAC heart and was further increased by vilda treatment. FGF21 was strongly expressed in cardiac fibroblasts than in cardiomyocytes in mouse heart after TAC with vilda treatment. Vilda treatment markedly induced FGF21 expression in human cardiac fibroblasts through a sirtuin (Sirt) 1-mediated pathway, suggesting that fibroblast-mediated FGF21 expression may regulate energy metabolism and exert vilda-mediated beneficial effects in stressed heart. Vilda induced a metabolic regulator, FGF21 expression in cardiac fibroblasts via Sirt1, and increased contractile efficiency in murine pressure-overloaded heart.

Association between lung ultrasound B-lines and exercise-induced pulmonary hypertension in patients with connective tissue disease.

BACKGROUND: Identification of elevation in pulmonary pressures during exercise may provide prognostic and therapeutic implications in patients with connective tissue disease (CTD). Interstitial lung disease (ILD) is common in CTD patients and subtle interstitial abnormalities detected by lung ultrasound could predict exercise-induced pulmonary hypertension (PH). METHODS AND RESULTS: Echocardiography and lung ultrasound were performed at rest and bicycle exercise in CTD patients (n = 41) and control subjects without CTD (n = 24). Ultrasound B-lines were quantified by scanning four intercostal spaces in the right hemithorax. We examined the association between total B-lines at rest and the development of exercise-induced PH during ergometry exercise. Compared to controls, the number of total B-lines at rest was higher in CTD patients (0 [0, 0] vs 2 [0, 9], P < .0001) and was correlated with radiological severity of ILD assessed by computed tomography (fibrosis score, r = .70, P < .0001). Pulmonary artery systolic pressure (PASP) was increased with ergometry exercise in CTD compared to controls (48 ± 14 vs 35 ± 13 mm Hg, P = .0006). The number of total B-lines at rest was highly correlated with higher PASP (r = .52, P < .0001) and poor right ventricular pulmonary artery coupling (tricuspid annular plane systolic excursion/PASP ratio, r = -.31, P = .01) during peak exercise. The number of resting B-lines predicted the development of exercise-induced PH with an area under the curve .79 (P = .0003). CONCLUSIONS: These data may suggest the value of a simple resting assessment of lung ultrasound as a potential tool for assessing the risk of exercise-induced PH in CTD patients.

Clinical features of dermatomyositis associated with anti-MDA5 antibodies by age.

OBJECTIVES: Anti-melanoma differentiation-associated gene 5 (MDA5) autoantibody-positive and age at onset ≥60 years are poor prognosis factors in polymyositis (PM) and dermatomyositis (DM) associated with interstitial lung disease (ILD) among Japanese patients. However, the influence of age on the clinical features of anti-MDA5 autoantibody-positive patients with DM remains unclear. METHODS: We retrospectively examined 40 patients with DM and anti-MDA5 autoantibodies according to age. We compared patients aged <60 and ≥60 years with respect to clinical features including laboratory test findings, high-resolution lung computed tomography data, treatment content, and complications such as infections and prognosis. We also examined clinical features between surviving and deceased patients in the older patient group. RESULTS: Of 40 enrolled patients, 13 were classified as old and 27 as young. Older patients had significantly fewer clinical symptoms including arthralgia/arthritis (p < .01), skin ulceration (p = .02), and higher mortality than younger patients (p = .02) complicated with rapidly progressive ILD (RP-ILD), combination immunosuppressive therapy, and strictly controlled infections. CONCLUSION: Clinical features and mortality of anti-MDA5 autoantibody-positive DM patients were influenced by age. Patients aged ≥60 years had a worse prognosis, and combination immunosuppressive therapy was often ineffective for RP-ILD in older patients.

Noninvasive evaluation of pulmonary artery pressure during exercise: the importance of right atrial hypertension.

INTRODUCTION: Identification of elevated pulmonary artery pressures during exercise has important diagnostic, prognostic and therapeutic implications. Stress echocardiography is frequently used to estimate pulmonary artery pressures during exercise testing, but data supporting this practice are limited. This study examined the accuracy of Doppler echocardiography for the estimation of pulmonary artery pressures at rest and during exercise. METHODS: Simultaneous cardiac catheterisation-echocardiographic studies were performed at rest and during exercise in 97 subjects with dyspnoea. Echocardiography-estimated pulmonary artery systolic pressure (ePASP) was calculated from the right ventricular (RV) to right atrial (RA) pressure gradient and estimated RA pressure (eRAP), and then compared with directly measured PASP and RAP. RESULTS: Estimated PASP was obtainable in 57% of subjects at rest, but feasibility decreased to 15-16% during exercise, due mainly to an inability to obtain eRAP during stress. Estimated PASP correlated well with direct PASP at rest (r=0.76, p<0.0001; bias -1 mmHg) and during exercise (r=0.76, p=0.001; bias +3 mmHg). When assuming eRAP of 10 mmHg, ePASP correlated with direct PASP (r=0.70, p<0.0001), but substantially underestimated true values (bias +9 mmHg), with the greatest underestimation among patients with severe exercise-induced pulmonary hypertension (EIPH). Estimation of eRAP during exercise from resting eRAP improved discrimination of patients with or without EIPH (area under the curve 0.81), with minimal bias (5 mmHg), but wide limits of agreement (-14-25 mmHg). CONCLUSIONS: The RV-RA pressure gradient can be estimated with reasonable accuracy during exercise when measurable. However, RA hypertension frequently develops in patients with EIPH, and the inability to noninvasively account for this leads to substantial underestimation of exercise pulmonary artery pressures.

Characterization of the Progression From Ambulatory to Hospitalized Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous syndrome. Some patients develop elevated filling pressures exclusively during exercise and never require hospitalization, whereas others periodically develop congestion that requires inpatient treatment. The features differentiating these cohorts are unclear. METHODS: We performed a secondary analysis of 7 National Institutes of Health-sponsored multicenter trials of HFpEF (EF ≥ 50%, N = 727). Patients were stratified by history of hospitalization because of HF, comparing patients never hospitalized (HFpEFNH) to those with a prior hospitalization (HFpEFPH). Currently hospitalized (HFpEFCH) patients were included to fill the spectrum. Clinical characteristics, cardiac structure, biomarkers, quality of life, functional capacity, activity levels, and outcomes were compared. RESULTS: As expected, HFpEFCH (n = 338) displayed the greatest severity of congestion, as assessed by N-terminal pro B-type natriuretic peptide levels, edema and orthopnea. As compared to HFpEFNH (n = 109), HFpEFPH (n = 280) displayed greater comorbidity burden, with more lung disease, renal dysfunction and anemia, along with lower activity levels (accelerometry), poorer exercise capacity (6-minute walk distance and peak exercise capacity), and more orthopnea. Patients with current or prior hospitalization displayed higher rates of future HF hospitalization, but quality of life was similarly impaired in all patients with HFpEF, regardless of hospitalization history. CONCLUSIONS: A greater burden of noncardiac organ dysfunction, sedentariness, functional impairment, and higher event rates distinguish patients with HFpEF and prior HF hospitalization from those never hospitalized. Despite lower event rates, quality of life is severely and similarly limited in patients with no history of hospitalization. These data suggest that the 2 clinical profiles of HFpEF may require different treatment strategies.

Adverse Renal Response to Decongestion in the Obese Phenotype of Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Patients with heart failure (HF) with preserved ejection fraction (HFpEF) and obesity display a number of pathophysiologic features that may render them more or less vulnerable to negative effects of decongestion on renal function, including greater right ventricular remodeling, plasma volume expansion and pericardial restraint. We aimed to contrast the renal response to decongestion in obese compared to nonobese patients with HFpEF METHODS AND RESULTS: National Institutes of Health heart failure network studies that enrolled patients with acute decompensated HFpEF (EF ≥ 50%) were included (DOSE, CARRESS, ROSE, and ATHENA). Obese HFpEF was defined as a body mass index ≥ 30 kg/m2. Compared to nonobese HFpEF (n = 118), patients with obese HFpEF (n = 214) were an average of 9 years younger (71 vs 80 years,< 0.001), were more likely to have diabetes (64% vs 31%, P< 0.001) but had less atrial fibrillation (56% vs 75%, P< 0.001). Renal dysfunction (glomerular filtration rate < 60 mL/min/1.73m2) was present in 82% of patients, and there was no difference at baseline between obese and nonobese patients. Despite similar weight loss through decongestive therapies, obese patients with HFpEF demonstrated greater rise in creatinine (Cr) and decline in glomerular filtration rate, with a 2-fold higher incidence of mild worsening renal function (rise in Cr ≥ 0.3 mg/dL) (28 vs 14%, P = 0.008) and a substantially greater increase in severe worsening of renal function (rise in Cr > 0.5 mg/dL) (9 vs 0%, P = 0.002). CONCLUSIONS: Despite being nearly a decade younger, obese patients with HFpEF experience greater deterioration in renal function during decongestion than do nonobese patients with HFpEF. Further study to elucidate the complex relationships between volume distribution, cardiorenal hemodynamics and adiposity in HFpEF is needed.

Deterioration in right ventricular structure and function over time in patients with heart failure and preserved ejection fraction.

AIMS: Prevalent right ventricular (RV) dysfunction (RVD) is associated with increased mortality in patients with heart failure with preserved ejection fraction (HFpEF), but no study has characterized long-term changes in RV structure and function within the same patient. METHODS AND RESULTS: Patients with unequivocal HFpEF defined by either invasive haemodynamics or hospitalization for pulmonary oedema (n = 271) underwent serial echocardiographic evaluations >6 months apart. Clinical, structural, functional, and haemodynamic characteristics were examined. Over a median of 4.0 years (interquartile range 2.1-6.1), there was a 10% decline in RV fractional area change and 21% increase in RV diastolic area (both P < 0.0001). These changes greatly exceeded corresponding changes in the left ventricle. The prevalence of tricuspid regurgitation increased by 45%. Of 238 patients with normal RV function at Exam 1, 55 (23%) developed RVD during follow-up. Development of RVD was associated with both prevalent and incident atrial fibrillation (AF), higher body weight, coronary disease, higher pulmonary artery and left ventricular filling pressures, and RV dilation. Patients with HFpEF developing incident RVD had nearly two-fold increased risk of death (adjusted hazard ratio 1.89, 95% confidence interval 1.01-3.44; P = 0.04). CONCLUSION: While previous attention has centred on the left ventricle in HFpEF, these data show that right ventricular structure and function deteriorate to greater extent over time when compared with changes in the left ventricle. Further study is required to evaluate whether interventions targeting modifiable risk factors identified for incident RVD, including abnormal haemodynamics, AF, coronary disease, and obesity, can prevent RVD and thus improve outcomes.

The neurohormonal basis of pulmonary hypertension in heart failure with preserved ejection fraction.

AIMS: Pulmonary hypertension (PH) represents an important phenotype among the broader spectrum of patients with heart failure with preserved ejection fraction (HFpEF), but its mechanistic basis remains unclear. We hypothesized that activation of endothelin and adrenomedullin, two counterregulatory pathways important in the pathophysiology of PH, would be greater in HFpEF patients with worsening PH, and would correlate with the severity of haemodynamic derangements and limitations in aerobic capacity and cardiopulmonary reserve. METHODS AND RESULTS: Plasma levels of C-terminal pro-endothelin-1 (CT-proET-1) and mid-regional pro-adrenomedullin (MR-proADM), central haemodynamics, echocardiography, and oxygen consumption (VO2) were measured at rest and during exercise in subjects with invasively-verified HFpEF (n = 38) and controls free of HF (n = 20) as part of a prospective study. Plasma levels of CT-proET-1 and MR-proADM were highly correlated with one another (r = 0.89, P < 0.0001), and compared to controls, subjects with HFpEF displayed higher levels of each neurohormone at rest and during exercise. C-terminal pro-endothelin-1 and MR-proADM levels were strongly correlated with mean pulmonary artery (PA) pressure (r = 0.73 and 0.65, both P < 0.0001) and pulmonary capillary wedge pressure (r = 0.67 and r = 0.62, both P < 0.0001) and inversely correlated with PA compliance (r = -0.52 and -0.43, both P < 0.001). As compared to controls, subjects with HFpEF displayed right ventricular (RV) reserve limitation, evidenced by less increases in RV s' and e' tissue velocities, during exercise. Baseline CT-proET-1 and MR-proADM levels were correlated with worse RV diastolic reserve (ΔRV e', r = -0.59 and -0.67, both P < 0.001), reduced cardiac output responses to exercise (r = -0.59 and -0.61, both P < 0.0001), and more severely impaired peak VO2 (r = -0.60 and -0.67, both P < 0.0001). CONCLUSION: Subjects with HFpEF display activation of the endothelin and adrenomedullin neurohormonal pathways, the magnitude of which is associated with pulmonary haemodynamic derangements, limitations in RV functional reserve, reduced cardiac output, and more profoundly impaired exercise capacity in HFpEF. Further study is required to evaluate for causal relationships and determine if therapies targeting these counterregulatory pathways can improve outcomes in patients with the HFpEF-PH phenotype. CLINICAL TRIAL REGISTRATION: NCT01418248; https://clinicaltrials.gov/ct2/results? term=NCT01418248&Search=Search.

The haemodynamic basis of lung congestion during exercise in heart failure with preserved ejection fraction.

AIMS: Increases in extravascular lung water (EVLW) during exercise contribute to symptoms, morbidity, and mortality in patients with heart failure and preserved ejection fraction (HFpEF), but the mechanisms leading to pulmonary congestion during exercise are not well-understood. METHODS AND RESULTS: Compensated, ambulatory patients with HFpEF (n = 61) underwent invasive haemodynamic exercise testing using high-fidelity micromanometers with simultaneous lung ultrasound, echocardiography, and expired gas analysis at rest and during submaximal exercise. The presence or absence of EVLW was determined by lung ultrasound to evaluate for sonographic B-line artefacts. An increase in EVLW during exercise was observed in 33 patients (HFpEFLW+, 54%), while 28 (46%) did not develop EVLW (HFpEFLW-). Resting left ventricular function was similar in the groups, but right ventricular (RV) dysfunction was two-fold more common in HFpEFLW+ (64 vs. 31%), with lower RV systolic velocity and RV fractional area change. As compared to HFpEFLW-, the HFpEFLW+ group displayed higher pulmonary capillary wedge pressure (PCWP), higher pulmonary artery (PA) pressures, worse RV-PA coupling, and higher right atrial (RA) pressures during exercise, with increased haemoconcentration indicating greater loss of water from the vascular space. The development of lung congestion during exercise was significantly associated with elevations in PCWP and RA pressure as well as impairments in RV-PA coupling (area under the curve values 0.76-0.84). CONCLUSION: Over half of stable outpatients with HFpEF develop increases in interstitial lung water, even during submaximal exercise. The acute development of lung congestion is correlated with increases in pulmonary capillary hydrostatic pressure that favours fluid filtration, and systemic venous hypertension due to altered RV-PA coupling, which may interfere with fluid clearance. CLINICAL TRIAL REGISTRATION: NCT02885636.

Obesity-Related Heart Failure with Preserved Ejection Fraction: Pathophysiology, Diagnosis, and Potential Therapies.

Obesity is very common in patients with heart failure with preserved ejection fraction (HFpEF). Obesity and increased adiposity have multiple adverse effects on the cardiovascular system, including hemodynamic, inflammatory, mechanical, and neurohormonal effects. Obesity and increased adiposity may be a promising target for therapy in HFpEF. This review summarizes the current understanding of the pathophysiology of obesity-related HFpEF, diagnostic evaluation of HFpEF among obese patients with dyspnea, and potential therapeutic options for the HFpEF obesity phenotype.

A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Diagnosis of heart failure with preserved ejection fraction (HFpEF) is challenging in euvolemic patients with dyspnea, and no evidence-based criteria are available. We sought to develop and then validate noninvasive diagnostic criteria that could be used to estimate the likelihood that HFpEF is present among patients with unexplained dyspnea to guide further testing. METHODS: Consecutive patients with unexplained dyspnea referred for invasive hemodynamic exercise testing were retrospectively evaluated. Diagnosis of HFpEF (case) or noncardiac dyspnea (control) was ascertained by invasive hemodynamic exercise testing. Logistic regression was performed to evaluate the ability of clinical findings to discriminate cases from controls. A scoring system was developed and then validated in a separate test cohort. RESULTS: The derivation cohort included 414 consecutive patients (267 cases with HFpEF and 147 controls; HFpEF prevalence, 64%). The test cohort included 100 consecutive patients (61 with HFpEF; prevalence, 61%). Obesity, atrial fibrillation, age >60 years, treatment with ≥2 antihypertensives, echocardiographic E/e' ratio >9, and echocardiographic pulmonary artery systolic pressure >35 mm Hg were selected as the final set of predictive variables. A weighted score based on these 6 variables was used to create a composite score (H2FPEF score) ranging from 0 to 9. The odds of HFpEF doubled for each 1-unit score increase (odds ratio, 1.98; 95% CI, 1.74-2.30; P<0.0001), with an area under the curve of 0.841 ( P<0.0001). The H2FPEF score was superior to a currently used algorithm based on expert consensus (increase in area under the curve of 0.169; 95% CI, 0.120-0.217; P<0.0001). Performance in the independent test cohort was maintained (area under the curve, 0.886; P<0.0001). CONCLUSIONS: The H2FPEF score, which relies on simple clinical characteristics and echocardiography, enables discrimination of HFpEF from noncardiac causes of dyspnea and can assist in determination of the need for further diagnostic testing in the evaluation of patients with unexplained exertional dyspnea.