Epidemiology of heart failure with preserved ejection fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) is a clinical syndrome associated with poor quality of life, substantial health-care resource utilization, and premature mortality. We summarize the current knowledge regarding the epidemiology of HFpEF with a focus on community-based studies relevant to quantifying the population burden of HFpEF. Current data regarding the prevalence and incidence of HFpEF in the community as well as associated conditions and risk factors, risk of morbidity and mortality after diagnosis, and quality of life are presented. In the community, approximately 50% of patients with HF have HFpEF. Although the age-specific incidence of HF is decreasing, this trend is less dramatic for HFpEF than for HF with reduced ejection fraction (HFrEF). The risk of HFpEF increases sharply with age, but hypertension, obesity, and coronary artery disease are additional risk factors. After adjusting for age and other risk factors, the risk of HFpEF is fairly similar in men and women, whereas the risk of HFrEF is much lower in women. Multimorbidity is common in both types of HF, but slightly more severe in HFpEF. A majority of deaths in patients with HFpEF are cardiovascular, but the proportion of noncardiovascular deaths is higher in HFpEF than HFrEF.

Suppression of Tumorigenicity 2 in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Soluble suppression of tumorigenicity 2 (sST2) receptor is a biomarker that is elevated in certain systemic inflammatory diseases. Comorbidity-driven microvascular inflammation is postulated to play a key role in heart failure with preserved ejection fraction (HFpEF) pathophysiology, but data on how sST2 relates to clinical characteristics or inflammatory conditions or biomarkers in HFpEF are limited. We sought to determine circulating levels and clinical correlates of sST2 in HFpEF.

METHODS AND RESULTS

At enrollment, patients (n=174) from the Phosphodiesterase-5 Inhibition to Improve Clinical Status And Exercise Capacity in Diastolic Heart Failure (RELAX) trial of sildenafil in HFpEF had sST2 levels measured. Clinical characteristics; cardiac structure and function; exercise performance; and biomarkers of neurohumoral activation, systemic inflammation and fibrosis, and myocardial necrosis were assessed in relation to sST2 levels. Median sST2 levels in male and female HFpEF patients were 36.7 ng/mL (range 30.9-49.2 ng/mL; reference range 4-31 ng/mL) and 30.8 ng/mL (range 25.3-39.3 ng/mL; reference range 2-21 ng/mL), respectively. Among HFpEF patients, higher sST2 levels were associated with the presence of diabetes mellitus; atrial fibrillation; renal dysfunction; right ventricular pressure overload and dysfunction; systemic congestion; exercise intolerance; and biomarkers of systemic inflammation and fibrosis, neurohumoral activation, and myocardial necrosis (P<0.05 for all). sST2 was not associated with left ventricular structure or left ventricular systolic or diastolic function.

CONCLUSIONS

In HFpEF, sST2 levels were associated with proinflammatory comorbidities, right ventricular pressure overload and dysfunction, and systemic congestion but not with left ventricular geometry or function. These data suggest that ST2 may be a marker of systemic inflammation in HFpEF and potentially of extracardiac origin.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00763867.

Impaired left ventricular global longitudinal strain in patients with heart failure with preserved ejection fraction: insights from the RELAX trial

BACKGROUND

While abnormal left ventricular (LV) global longitudinal strain (GLS) has been described in patients with heart failure with preserved ejection fraction (HFpEF), its prevalence and clinical significance are poorly understood.

METHODS AND RESULTS

Patients enrolled in the RELAX trial of sildenafil in HFpEF (LV ejection fraction ≥50%) in whom two-dimensional, speckle-tracking LV GLS was possible (n = 187) were analysed. The distribution of LV GLS and its associations with clinical characteristics, LV structure and function, biomarkers, exercise capacity and quality of life were assessed. Baseline median LV GLS was -14.6% (25th and 75th percentile, -17.0% and -11.9%, respectively) and abnormal (≥ - 16%) in 122/187 (65%) patients. Patients in the tertile with the best LV GLS had lower N-terminal pro-brain natriuretic peptide (NT-proBNP) [median 505 pg/mL (161, 1065) vs. 875 pg/mL (488, 1802), P = 0.008) and lower collagen III N-terminal propeptide (PIIINP) levels [median 6.7 µg/L (5.1, 8.1) vs. 8.1 µg/L (6.5, 10.5), P = 0.001] compared with the tertile with the worst LV GLS. There was also a modest linear relationship with LV GLS and log-transformed NT-proBNP and PIIINP (r = 0.29, P < 0.001 and r = 0.19, P = 0.009, respectively). We observed no linear association of LV GLS with Minnesota Living with Heart Failure scores, 6-min walk distance, peak oxygen consumption, or expiratory minute ventilation/carbon dioxide excretion slope.

CONCLUSIONS

Impaired LV GLS is common among HFpEF patients, indicating the presence of covert systolic dysfunction despite normal LV ejection fraction. Impaired LV GLS was associated with biomarkers of wall stress and collagen synthesis and diastolic dysfunction but not with quality of life or exercise capacity, suggesting other processes may be more responsible for these aspects of the HFpEF syndrome.

Risk of Heart Failure With Preserved Ejection Fraction in Older Women After Contemporary Radiotherapy for Breast Cancer

BACKGROUND

Cardiomyocytes are resistant to radiation. However, cardiac radiation exposure causes coronary microvascular endothelial inflammation, a perturbation implicated in the pathogenesis of heart failure (HF) and particularly HF with preserved ejection fraction (HFpEF). Radiotherapy for breast cancer results in variable cardiac radiation exposure and may increase the risk of HF.

METHODS

We conducted a population-based case-control study of incident HF in 170 female residents of Olmsted County, Minnesota (59 cases and 111 controls), who underwent contemporary (1998-2013) radiotherapy for breast cancer with computed tomography-assisted radiotherapy planning. Controls were matched to cases for age, tumor side, chemotherapy use, diabetes mellitus, and hypertension. Mean cardiac radiation dose (MCRD) in each patient was calculated from the patient's computed tomography images and radiotherapy plan.

RESULTS

Mean age at radiotherapy was 69±9 years. Of HF cases, 38 (64%) had EF≥50% (HFpEF), 18 (31%) had EF<50% (HF with reduced EF), and 3 (5%) did not have EF measured. The EF was ≥40% in 50 of the 56 HF cases (89%) with an EF measurement. The mean interval from radiotherapy to HF was 5.8±3.4 years. The odds of HF was higher in patients with a history of ischemic heart disease or atrial fibrillation. The MCRD was 2.5 Gy (range, 0.2-13.1 Gy) and higher in cases (3.3±2.7 Gy) than controls (2.1±2.0 Gy; P=0.004). The odds ratio (95% confidence interval) for HF per log MCRD was 9.1 (3.4-24.4) for any HF, 16.9 (3.9-73.7) for HFpEF, and 3.17 (0.8-13.0) for HF with reduced EF. The increased odds of any HF or HFpEF with increasing MCRD remained significant after adjustment for HF risk factors and in sensitivity analyses matching by cancer stage rather than tumor side. Only 18.6% of patients experienced new or recurrent ischemic events between radiotherapy and the onset of HF.

CONCLUSIONS

The relative risk of HFpEF increases with increasing cardiac radiation exposure during contemporary conformal breast cancer radiotherapy. These data emphasize the importance of radiotherapy techniques that limit MCRD during breast cancer treatment. Moreover, these data provide further support for the importance of coronary microvascular compromise in the pathophysiology of HFpEF.

Left Atrial Structure and Function in Heart Failure with Preserved Ejection Fraction: A RELAX Substudy

Given the emerging recognition of left atrial structure and function as an important marker of disease in heart failure with preserved ejection fraction (HF-pEF), we investigated the association between left atrial volume and function with markers of disease severity and cardiac structure in HF-pEF. We studied 100 patients enrolled in the PhosphdiesteRasE-5 Inhibition to Improve CLinical Status and EXercise Capacity in Diastolic Heart Failure (RELAX) trial who underwent cardiac magnetic resonance (CMR), cardiopulmonary exercise testing, and blood collection before randomization. Maximal left atrial volume index (LAVi; N = 100), left atrial emptying fraction (LAEF; N = 99; including passive and active components (LAEFP, LAEFA; N = 80, 79, respectively) were quantified by CMR. After adjustment for multiple testing, maximal LAVi was only associated with age (ρ = 0.39), transmitral filling patterns (medial E/e' ρ = 0.43), and N-terminal pro-BNP (NT-proBNP; ρ = 0.65; all p<0.05). Lower LAEF was associated with older age, higher transmitral E/A ratio and higher NT-proBNP. Peak VO2 and VE/VCO2 slope were not associated with left atrial structure or function. After adjustment for age, sex, transmitral E/A ratio, CMR LV mass, LV ejection fraction, and creatinine clearance, NT-proBNP remained associated with maximal LAVi (β = 0.028, p = 0.0007) and total LAEF (β = -0.033, p = 0.001). Passive and active LAEF were most strongly associated with age and NT-proBNP, but not gas exchange or other markers of ventricular structure or filling properties. Left atrial volume and emptying function are associated most strongly with NT-proBNP and diastolic filling properties, but not significantly with gas exchange, in HFpEF. Further research to explore the relevance of left atrial structure and function in HF-pEF is warranted.

Insulin-Like Growth Factor-Binding Protein-7 as a Biomarker of Diastolic Dysfunction and Functional Capacity in Heart Failure With Preserved Ejection Fraction: Results From the RELAX Trial

OBJECTIVES

This study sought to investigate relationships between insulin-like growth factor-binding protein-7 (IGFBP7) and parameters of diastolic function or functional capacity in patients with heart failure and preserved ejection fraction (HFpEF) who were randomized to receive sildenafil or placebo.

BACKGROUND

IGFBP7 was previously found to be associated with diastolic function in heart failure with reduced ejection fraction, but it is unclear whether these associations are present in HFpEF.

METHODS

At baseline and 24 weeks, IGFBP7, imaging studies, and peak oxygen consumption (Vo2max) were obtained and compared in 160 patients with HFpEF who were randomized to receive sildenafil or placebo.

RESULTS

Patients with supramedian baseline IGFBP7 concentrations were older, had signs of systemic congestion and worse renal function, and had higher concentrations of prognostic heart failure biomarkers including amino-terminal pro-B-type natriuretic peptide (p < 0.05). Higher baseline IGFBP7 was modestly correlated with worse diastolic function: higher E velocity (Spearman correlation [ρ] = 0.40), E/E' (ρ = 0.40), left atrial volume index (ρ = 0.39), and estimated right ventricular systolic pressure (ρ = 0.41; all p < 0.001) and weakly correlated with transmitral E/A (ρ = 0.26; p = 0.006). Notably, change in IGFBP7 was significantly correlated with change in E, E/A, E/E', and right ventricular systolic pressure. Elevated baseline IGFBP7 was associated with lower baseline Vo2max (13.2 vs. 11.1 ml/min/kg; p < 0.001), and change in IGFBP7 was weakly inversely correlated with change in Vo2max (ρ = -0.19; p = 0.01). Subjects receiving sildenafil had a decrease in IGFBP7 over 24 weeks, in contrast to placebo-treated patients (median change in IGFBP7 -1.5 vs. +13.6 ng/ml; p < 0.001).

CONCLUSIONS

In patients with HFpEF, IGFBP7 may be a novel biomarker of diastolic function and exercise capacity.

Evaluation of Novel Metrics of Symptom Relief in Acute Heart Failure: The Worst Symptom Score

OBJECTIVE

To characterize a novel "worst"-symptom visual analogue scale (WS-VAS) versus the traditional dyspnea visual analogue scale (DVAS) in an acute heart failure (AHF) trial.

BACKGROUND

AHF trials assess symptom relief as a pivotal endpoint with the use of dyspnea scores. However, many AHF patients' worst presenting symptom (WS) may not be dyspnea. We hypothesized that a WS-VAS may reflect clinical improvement better than DVAS in AHF.

METHODS AND RESULTS

AHF patients (n = 232) enrolled in the Renal Optimization Strategies Evaluation in Acute Heart Failure (ROSE-AHF) Trial indicated their WS at enrollment and completed DVAS and WS-VAS at enrollment and 24, 48, and 72 hours. Dyspnea was the WS in 61%, body swelling in 29%, and fatigue in 10% of patients. Clinical characteristics differed by WS. In all patients, DVAS scores were higher (less severe symptoms) than WS-VAS and the change in WS-VAS over 72 hours was greater than the change in DVAS (P < .001). Changes in DVAS were smaller in patients with body swelling and fatigue than in patients with dyspnea as their WS (P = .002), whereas changes in the WS-VAS were similar regardless of patients' WS. Neither score, nor its change, was associated with available decongestion markers (change in N-terminal pro-B-type natriuretic peptide, weight or cumulative 72-hour urine volume).

CONCLUSIONS

Many AHF patients have symptoms other than dyspnea as their most bothersome symptom. The WS-VAS better reflects symptom improvement across the spectrum of AHF phenotypes. Symptom relief and decongestion were not correlated in this AHF study.

Left Atrial Remodeling and Atrioventricular Coupling in a Canine Model of Early Heart Failure With Preserved Ejection Fraction

BACKGROUND

Left atrial (LA) compliance and contractility influence left ventricular stroke volume. We hypothesized that diminished LA compliance and contractile function occur early during the development of heart failure with preserved ejection fraction (HFpEF) and impair overall cardiac performance.

METHODS AND RESULTS

Cardiac magnetic resonance imaging, echocardiography, left ventricular and LA pressure-volume studies, and tissue analyses were performed in a model of early HFpEF (elderly dogs, renal wrap-induced hypertension, exogenous aldosterone; n=9) and young control dogs (sham surgery; n=13). Early HFpEF was associated with LA enlargement, cardiomyocyte hypertrophy, and enhanced LA contractile function (median active emptying fraction 16% [95% confidence interval, 13-24]% versus 12 [10-14]%, P=0.008; end-systolic pressure-volume relationship slope 2.4 [1.9-3.2]mm Hg/mL HFpEF versus 1.5 [1.2-2.2]mm Hg/mL controls, P=0.01). However, atrioventricular coupling was impaired and the curvilinear LA end-reservoir pressure-volume relationship was shifted upward/leftward in HFpEF (LA stiffness constant [β_LA] 0.16 [0.11-0.18]mm Hg/mL versus 0.06 [0.04-0.10]mm Hg/mL controls; P=0.002), indicating reduced LA compliance. Impaired atrioventricular coupling and lower LA compliance correlated with lower left ventricular stroke volume. Total fibrosis and titin isoform composition were similar between groups; however, titin was hyperphosphorylated in HFpEF and correlated with β_LA. LA microvascular reactivity was diminished in HFpEF versus controls. LA microvascular density tended to be lower in HFpEF and inversely correlated with β_LA.

CONCLUSIONS

In early-stage hypertensive HFpEF, LA cardiomyocyte hypertrophy, titin hyperphosphorylation, and microvascular dysfunction occur in association with increased systolic and diastolic LA chamber stiffness, impaired atrioventricular coupling, and decreased left ventricular stroke volume. These data indicate that maladaptive LA remodeling occurs early during HFpEF development, supporting a concept of global myocardial remodeling.

FOXO3a regulates BNIP3 and modulates mitochondrial calcium, dynamics, and function in cardiac stress

The forkhead box O3a (FOXO3a) transcription factor has been shown to regulate glucose metabolism, muscle atrophy, and cell death in postmitotic cells. Its role in regulation of mitochondrial and myocardial function is not well studied. Based on previous work, we hypothesized that FOXO3a, through BCL2/adenovirus E1B 19-kDa protein-interacting protein 3 (BNIP3), modulates mitochondrial morphology and function in heart failure (HF). We modulated the FOXO3a-BNIP3 pathway in normal and phenylephrine (PE)-stressed adult cardiomyocytes (ACM) in vitro and developed a cardiotropic adeno-associated virus serotype 9 encoding dominant-negative FOXO3a (AAV9.dn-FX3a) for gene delivery in a rat model of HF with preserved ejection fraction (HFpEF). We found that FOXO3a upregulates BNIP3 expression in normal and PE-stressed ACM, with subsequent increases in mitochondrial Ca²⁺, leading to decreased mitochondrial membrane potential, mitochondrial fragmentation, and apoptosis. Whereas dn-FX3a attenuated the increase in BNIP3 expression and its consequences in PE-stressed ACM, AAV9.dn-FX3a delivery in an experimental model of HFpEF decreased BNIP3 expression, reversed adverse left ventricular remodeling, and improved left ventricular systolic and, particularly, diastolic function, with improvements in mitochondrial structure and function. Moreover, AAV9.dn-FX3a restored phospholamban phosphorylation at S16 and enhanced dynamin-related protein 1 phosphorylation at S637. Furthermore, FOXO3a upregulates maladaptive genes involved in mitochondrial apoptosis, autophagy, and cardiac atrophy. We conclude that FOXO3a activation in cardiac stress is maladaptive, in that it modulates Ca²⁺ cycling, Ca²⁺ homeostasis, and mitochondrial dynamics and function. Our results suggest an important role of FOXO3a in HF, making it an attractive potential therapeutic target.

Ventricular-Arterial Function and Coupling in the Adult Fontan Circulation

Background

In adult Fontan patients, ventricular or arterial dysfunction may impact homeostasis of the Fontan circulation and predispose to heart failure. We sought to characterize ventricular‐arterial (VA) properties in adult Fontan patients.

Methods and Results

Adult Fontan patients (n=170), including those with right (SRV, n=57) and left (SLV, n=113) dominant ventricular morphology, were compared to age, sex, and body size matched controls (n=170). Arterial function, load‐insensitive measures of contractility, VA coupling, diastolic function, and ventricular efficiency were assessed. Compared to controls, Fontan patients had similar arterial (Ea), but lower end‐systolic ventricular (Ees), elastance, preload recruitable stroke work and peak power index, impaired VA coupling, eccentric remodeling, reduced ventricular efficiency and increased diastolic stiffness (P<0.05 for all). Ventricular efficiency declined steeply with higher heart rate in Fontan, but not control, patients. Among Fontan patients (n=123) and controls (n=162) with preserved cardiac index (CI; ≥2.5 L/min per m²), Fontan patients had worse contractility than controls, but CI was preserved owing to relative tachycardia, lower afterload, and eccentric remodeling. However, 25% of Fontan patients had reduced CI and were distinguished from those with preserved CI by less‐eccentric remodeling and worse diastolic function, rather than more‐impaired contractility.

Conclusions

Adult Fontan patients have contractile and diastolic dysfunction with normal afterload, impaired VA coupling, and reduced ventricular efficiency with heightened sensitivity to heart rate. Maintenance of CI is dependent on lower afterload, eccentric remodeling, and relative preservation of diastolic function. These data contribute to our understanding of circulatory physiology in adult Fontan patients.

A modifier screen identifies DNAJB6 as a cardiomyopathy susceptibility gene

Mutagenesis screening is a powerful forward genetic approach that has been successfully applied in lower-model organisms to discover genetic factors for biological processes. This phenotype-based approach has yet to be established in vertebrates for probing major human diseases, largely because of the complexity of colony management. Herein, we report a rapid strategy for identifying genetic modifiers of cardiomyopathy (CM). Based on the application of doxorubicin stress to zebrafish insertional cardiac (ZIC) mutants, we identified 4 candidate CM-modifying genes, of which 3 have been linked previously to CM. The long isoform of DnaJ (Hsp40) homolog, subfamily B, member 6b (dnajb6b(L)) was identified as a CM susceptibility gene, supported by identification of rare variants in its human ortholog DNAJB6 from CM patients. Mechanistic studies indicated that the deleterious, loss-of-function modifying effects of dnajb6b(L) can be ameliorated by inhibition of ER stress. In contrast, overexpression of dnajb6(L) exerts cardioprotective effects on both fish and mouse CM models. Together, our findings establish a mutagenesis screening strategy that is scalable for systematic identification of genetic modifiers of CM, feasible to suggest therapeutic targets, and expandable to other major human diseases.

Rationale and Design of the ATHENA-HF Trial: Aldosterone Targeted Neurohormonal Combined With Natriuresis Therapy in Heart Failure

Although therapy with mineralocorticoid receptor antagonists (MRAs) is recommended for patients with chronic heart failure (HF) with reduced ejection fraction and in post-infarction HF, it has not been studied well in acute HF (AHF) despite being commonly used in this setting. At high doses, MRA therapy in AHF may relieve congestion through its natriuretic properties and mitigate the effects of adverse neurohormonal activation associated with intravenous loop diuretics. The ATHENA-HF (Aldosterone Targeted Neurohormonal Combined with Natriuresis Therapy in Heart Failure) trial is a randomized, double-blind, placebo-controlled study of the safety and efficacy of 100 mg/day spironolactone versus placebo (or continued low-dose spironolactone use in participants who are already receiving spironolactone at baseline) in 360 patients hospitalized for AHF. Patients are randomized within 24 h of receiving the first dose of intravenous diuretics. The primary objective is to determine if high-dose spironolactone, compared with standard care, will lead to greater reductions in N-terminal pro-B-type natriuretic peptide levels from randomization to 96 h. The secondary endpoints include changes in the clinical congestion score, dyspnea relief, urine output, weight change, loop diuretic dose, and in-hospital worsening HF. Index hospital length of stay and 30-day clinical outcomes will be assessed. Safety endpoints include risk of hyperkalemia and renal function. Differences among patients with reduced versus preserved ejection fraction will be determined. (Study of High-dose Spironolactone vs. Placebo Therapy in Acute Heart Failure [ATHENA-HF]; NCT02235077).

Effects of Liraglutide on Clinical Stability Among Patients With Advanced Heart Failure and Reduced Ejection Fraction: A Randomized Clinical Trial

IMPORTANCE

Abnormal cardiac metabolism contributes to the pathophysiology of advanced heart failure with reduced left ventricular ejection fraction (LVEF). Glucagon-like peptide 1 (GLP-1) agonists have shown cardioprotective effects in early clinical studies of patients with advanced heart failure, irrespective of type 2 diabetes status.

OBJECTIVE

To test whether therapy with a GLP-1 agonist improves clinical stability following hospitalization for acute heart failure.

DESIGN, SETTING, AND PARTICIPANTS

Phase 2, double-blind, placebo-controlled randomized clinical trial of patients with established heart failure and reduced LVEF who were recently hospitalized. Patients were enrolled between August 2013 and March 2015 at 24 US sites.

INTERVENTIONS

The GLP-1 agonist liraglutide (n = 154) or placebo (n = 146) via a daily subcutaneous injection; study drug was advanced to a dosage of 1.8 mg/d during the first 30 days as tolerated and continued for 180 days.

MAIN OUTCOMES AND MEASURES

The primary end point was a global rank score in which all patients, regardless of treatment assignment, were ranked across 3 hierarchical tiers: time to death, time to rehospitalization for heart failure, and time-averaged proportional change in N-terminal pro-B-type natriuretic peptide level from baseline to 180 days. Higher values indicate better health (stability). Exploratory secondary outcomes included primary end point components, cardiac structure and function, 6-minute walk distance, quality of life, and combined events.

RESULTS

Among the 300 patients who were randomized (median age, 61 years [interquartile range {IQR}, 52-68 years]; 64 [21%] women; 178 [59%] with type 2 diabetes; median LVEF of 25% [IQR, 19%-33%]; median N-terminal pro-B-type natriuretic peptide level of 2049 pg/mL [IQR, 1054-4235 pg/mL]), 271 completed the study. Compared with placebo, liraglutide had no significant effect on the primary end point (mean rank of 146 for the liraglutide group vs 156 for the placebo group, P = .31). There were no significant between-group differences in the number of deaths (19 [12%] in the liraglutide group vs 16 [11%] in the placebo group; hazard ratio, 1.10 [95% CI, 0.57-2.14]; P = .78) or rehospitalizations for heart failure (63 [41%] vs 50 [34%], respectively; hazard ratio, 1.30 [95% CI, 0.89-1.88]; P = .17) or for the exploratory secondary end points. Prespecified subgroup analyses in patients with diabetes did not reveal any significant between-group differences. The number of investigator-reported hyperglycemic events was 16 (10%) in the liraglutide group vs 27 (18%) in the placebo group and hypoglycemic events were infrequent (2 [1%] vs 4 [3%], respectively).

CONCLUSIONS AND RELEVANCE

Among patients recently hospitalized with heart failure and reduced LVEF, the use of liraglutide did not lead to greater posthospitalization clinical stability. These findings do not support the use of liraglutide in this clinical situation.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01800968.

Impaired Right Ventricular-Pulmonary Arterial Coupling and Effect of Sildenafil in Heart Failure With Preserved Ejection Fraction: An Ancillary Analysis From the Phosphodiesterase-5 Inhibition to Improve Clinical Status And Exercise Capacity in Diastolic Heart Failure (RELAX) Trial

BACKGROUND

Right ventricular (RV) dysfunction (RVD) is a poor prognostic factor in heart failure with preserved ejection fraction (HFpEF). The physiological perturbations associated with RVD or RV function indexed to load (RV-pulmonary arterial [PA] coupling) in HFpEF have not been defined. HFpEF patients with marked impairment in RV-PA coupling may be uniquely sensitive to sildenafil.

METHODS AND RESULTS

In a subset of HFpEF patients enrolled in the Phosphodiesteas-5 Inhibition to Improve Clinical Status And Exercise Capacity in Diastolic Heart Failure (RELAX) trial, physiological variables and therapeutic effect of sildenafil were examined relative to the severity of RVD (tricuspid annular plane systolic excursion [TAPSE]) and according to impairment in RV-PA coupling (TAPSE/pulmonary artery systolic pressure) ratio. The prevalence of atrial fibrillation and diuretic use, n-terminal probrain natriuretic peptide levels, renal dysfunction, neurohumoral activation, myocardial necrosis and fibrosis biomarkers, and the severity of diastolic dysfunction all increased with severity of RVD. Peak oxygen consumption decreased and ventilatory inefficiency (VE/VCO2 slope) increased with increasing severity of RVD. Many but not all physiological derangements were more closely associated with the TAPSE/pulmonary artery systolic pressure ratio. Compared with placebo, at 24 weeks, TAPSE decreased, and peak oxygen consumption and VE/CO2 slope were unchanged with sildenafil. There was no interaction between RV-PA coupling and treatment effect, and sildenafil did not improve TAPSE, peak oxygen consumption, or VE/VCO2 in patients with pulmonary hypertension and RVD.

CONCLUSIONS

HFpEF patients with RVD and impaired RV-PA coupling have more advanced heart failure. In RELAX patients with RVD and impaired RV-PA coupling, sildenafil did not improve RV function, exercise capacity, or ventilatory efficiency.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00763867.

Abstract 225: Patient Activation is Low and Associated With Early Post-discharge Outcomes in Patients Hospitalized With Acute Decompensated Heart Failure

Background: Recent studies have suggested that patient activation, or having the knowledge, skills and confidence to manage one’s own health, has a substantial impact on patient behaviors and health outcomes. However, the role of activation in patients with heart failure is unknown.

Methods: We prospectively recruited Southeastern Minnesota residents hospitalized with acute decompensated heart failure (ADHF) from January 2014 through July 2015. Activation was measured by face-to-face questionnaire using the Patient Activation Measure (PAM) and patients were categorized into four activation levels (lowest to highest activation) per PAM guidelines. Logistic regression was used to examine the association between activation level and discharge location and early post-discharge outcomes.

Results: Among the 302 patients enrolled, the mean age was 77.3 years, 57.3% were men, and 46.8% had preserved ejection fraction. Median (25th-75th percentile) length of stay was 4 (3-7) days and 7 (2.3%) patients died prior to discharge. Among survivors, 73.3% discharged to home, while the remainder went to skilled nursing facilities (23.0%), assisted living facilities (2.0%) or other arrangements (1.4%). The 30-day mortality rate was 7.0% and the 30-day readmission rate was 21.2%. The number (%) of patients in each activation category from highest to lowest was 9 (3.0%), 121 (40.1%), 122 (40.4%), and 50 (16.6%). Patients with lower activation were older, less educated, had worse overall and financial satisfaction, and worse health literacy. They more often discharged to skilled nursing facilities and had higher 30-day mortality, though 30-day readmission did not differ by activation (Figure). Adjusting for age, patients in the lowest activation level were at 3.1-fold increased odds of discharging to a skilled nursing facility and 6.0-fold increased odds of dying within 30 days of hospital discharge compared with patients in the highest two activation levels.

Conclusions: Patients hospitalized with ADHF with lower activation are less satisfied, have worse health literacy, more often require skilled care and are at increased risk for early post-discharge mortality. Activation is easy to measure, identifies a high-risk subgroup, and is potentially modifiable.

Chronic Peptide Therapy With B-Type Natriuretic Peptide in Patients With Pre-Clinical Diastolic Dysfunction (Stage B Heart Failure)

OBJECTIVES

This study determined whether there is development of tachyphylaxis to enhancement of cardiorenal response to acute volume loading (AVL) with B-type natriuretic peptide (BNP) after 12-week, twice-daily subcutaneous BNP administration in patients with preclinical diastolic dysfunction (PDD).

BACKGROUND

PDD is characterized by normal systolic function and moderate or severe diastolic dysfunction but no symptoms of heart failure (HF). Impairment in cardiorenal endocrine response to stress by AVL exists in PDD and is corrected by acute administration of subcutaneous BNP.

METHODS

A double-blinded, placebo-controlled proof-of-concept study was conducted to compare 12 weeks of twice daily subcutaneous BNP, 10 μg/kg (n = 24), versus placebo (n = 12) in PDD. Subjects underwent 2 study visits, at baseline and after 12 weeks. At each study visit, echocardiography, renal, and neurohumoral assessments were performed before and after intravascular AVL.

RESULTS

Among those with PDD, there was a statistically significant improvement in diastolic function after 12 weeks of BNP, as measured by a decrease in the Doppler E/e' ratio (where E is early mitral inflow velocity and e' is mitral annulus early diastolic motion) (p = 0.004) and improvement of diastolic dysfunction grade (p = 0.008). After 12 weeks, there was statistically significantly greater sodium excretion, urine flow, and urinary cyclic guanosine monophosphate excretion to AVL (all p < 0.001), as well as a trend toward greater glomerular filtration rate (p = 0.050) in the BNP group as compared to the placebo group.

CONCLUSIONS

In subjects with PDD, chronic BNP administration resulted in sustained improvement in diastolic function without development of tachyphylaxis to the enhancement of cardiorenal response to volume expansion with BNP. (Human Brain Natriuretic Peptide [BNP] [or Nesiritide] to Help Heart, Kidney and Humoral Function; NCT00405548).

Evaluation of a provocative dyspnea severity score in acute heart failure

BACKGROUND

The acute heart failure (AHF) Syndromes International Working Group proposed that dyspnea be assessed under standardized, incrementally provocative maneuvers and called for studies to assess the feasibility of this approach. We sought to assess the feasibility and statistical characteristics of a novel provocative dyspnea severity score (pDS) versus the traditional dyspnea visual analog scale (DVAS) in an AHF trial.

METHODS

At enrollment, 24, 48 and 72hours, 230 ROSE-AHF patients completed a DVAS. Dyspnea was then assessed with 5-point Likert dyspnea scales administered during 4 stages (A: upright-with O2, B: upright-without O2, C: supine-without O2 and D: exercise-without O2). Patients with moderate or less dyspnea were eligible for the next stage.

RESULTS

At enrollment, oxygen withdrawal and supine provocation were highly feasible (≥97%), provoking more severe dyspnea (≥1 Likert point) in 24% and 42% of eligible patients, respectively. Exercise provocation had low feasibility with 38% of eligible patients unable to exercise due to factors other than dyspnea. A pDS was constructed from Likert scales during the 3 feasible assessment conditions (A-C). Relative to DVAS, the distribution of the pDS was more skewed with a high "ceiling effect" at enrollment (23%) limiting sensitivity to change. Change in pDS was not related to decongestion or 60-day outcomes.

CONCLUSIONS

Although oxygen withdrawal and supine provocation are feasible and elicit more severe dyspnea, exercise provocation had unacceptable feasibility in this AHF cohort. The statistical characteristics of a pDS based on feasible provocation measures do not support its potential as a robust dyspnea assessment tool in AHF.