Prescription of beta-blockers in patients with advanced heart failure and preserved left ventricular ejection fraction. Clinical implications and survival

Revisiting Beta-Blocker Therapy in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a heterogenous disorder and tends to be predominant in elderly, female, and obese patients. HFpEF has been classified using various cut-offs of left ventricular ejection fraction in the published studies with a current cut-off of ≥50%. The evidence of beta-blocker therapy in HFpEF patients showed conflicting findings with variably reported efficacy. This review aims to examine the published studies on the use of beta blockers for the treatment of patients with HFpEF.

Comparative effects of nebivolol and carvedilol on left ventricular diastolic function in older patients with heart failure and preserved ejection fraction

Background

Although many studies have compared carvedilol and nebivolol in heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF), such comparative studies for the elderly have not been reported yet. Nebivolol is known to be effective for improving diastolic function of elderly patients with HF. Thus, this study aimed to determine whether nebivolol could improve LV diastolic function to a greater extent than carvedilol in older patients aged over 70 years.

Methods

This trial was a prospective, randomized, open-label, single-center, active-controlled study that enrolled 62 patients with class II or III HF over 70 years of age with an LVEF ≥40%. Patients were randomized into a carvedilol group or a nebivolol group. Transthoracic echocardiography was performed at baseline and 12 months by the same investigator who was blinded to clinical data. The primary endpoint was E/e' measured by echocardiographic evaluation 12 months after treatment.

Results

The median duration of follow-up was 24 months. Baseline clinical characteristics and echocardiographic parameters, such as LV diastolic function indices, did not differ significantly between carvedilol and nebivolol groups. Twelve-month follow-up echocardiography data showed no significant difference in E/e' or other LV diastolic function indices between the two groups. There were no significant changes in echocardiographic parameters over 12 months in either group.

Conclusions

There was no difference between carvedilol and nebivolol for improving diastolic function of elderly HF patients with LVEF ≥40%. This study showed no superiority of nebivolol over carvedilol in elderly patients with HF.

Effect of Breathing Oxygen-Enriched Air on Exercise Performance in Patients With Pulmonary Hypertension Due to Heart Failure With Preserved Ejection Fraction: A Randomized, Placebo-Controlled, Crossover Trial

Objective: To evaluate the effects of breathing oxygen-enriched air (oxygen) on exercise performance in patients with pulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF).

Methods: Ten patients with PH-HFpEF (five women, age 60 ± 9 y, mPAP 37 ± 14 mmHg, PAWP 18 ± 2 mmHg, PVR 3 ± 3 WU, resting SpO₂ 98 ± 2%) performed two-cycle incremental exercise tests (IET) and two constant-work-rate exercise test (CWRET) at 75% maximal work-rate (W_max), each with ambient air (FiO₂ 0.21) and oxygen (FiO₂ 0.5) in a randomized, single-blinded, cross-over design. The main outcomes were the change in W_max (IET) and cycling time (CWRET) with oxygen vs. air. Blood gases at rest and end-exercise, dyspnea by Borg CR10 score at end-exercise; continuous SpO₂, minute ventilation (V'E), carbon dioxide output (V'CO₂), and cerebral and quadricep muscle tissue oxygenation (CTO and QMTO) were measured.

Results: With oxygen vs. air, W_max (IET) increased from 94 ± 36 to 99 ± 36 W, mean difference (95% CI) 5.4 (0.9–9.8) W, p = 0.025, and cycling time (CWRET) from 532 ± 203 to 680 ± 76 s, +148 (31.8–264) s, p = 0.018. At end-exercise with oxygen, Borg dyspnea score and V'E/V'CO₂ were lower, whereas PaO₂ and end-tidal PaCO₂ were higher. Other parameters were unchanged.

Conclusion: Patients with PH-HFpEF not revealing resting hypoxemia significantly improved their exercise performance while breathing oxygen-enriched air along with less subjective dyspnea sensation, a better blood oxygenation, and an enhanced ventilatory efficiency. Future studies should investigate whether prolonged training with supplemental oxygen would increase the training effect and, potentially, daily activity for PH-HFpEF patients.

Clinical Trial Registration: [clinicaltrials.gov], identifier [NCT04157660].

Heart Failure With Preserved Ejection Fraction: A Comprehensive Review and Update of Diagnosis, Pathophysiology, Treatment, and Perioperative Implications

Almost three-quarters of all heart failure patients who are older than 65 have heart failure with preserved ejection fraction (HFpEF). The proportion and hospitalization rate of patients with HFpEF are increasing steadily relative to patients in whom heart failure occurs as result of reduced ejection fraction. The predominance of the HFpEF phenotype most likely is explained by the prevalence of medical conditions associated with an aging population. A multitude of age-related, medical, and lifestyle risk factors for HFpEF have been identified as potential causes for the sustained low-grade proinflammatory state that accelerates disease progression. Profound left ventricular (LV) systolic and diastolic stiffening, elevated LV filling pressures, reduced arterial compliance, left atrial hypertension, pulmonary venous congestion, and microvascular dysfunction characterize HFpEF, but pulmonary arterial hypertension, right ventricular dilation and dysfunction, and atrial fibrillation also frequently occur. These cardiovascular features make patients with HFpEF exquisitely sensitive to the development of hypotension in response to acute declines in LV preload or afterload that may occur during or after surgery. With the exception of symptom mitigation, lifestyle modifications, and rigorous control of comorbid conditions, few long-term treatment options exist for these unfortunate individuals. Patients with HFpEF present for surgery on a regular basis, and anesthesiologists need to be familiar with this heterogeneous and complex clinical syndrome to provide successful care. In this article, the authors review the diagnosis, pathophysiology, and treatment of HFpEF and also discuss its perioperative implications.

Association is not causation: treatment effects cannot be estimated from observational data in heart failure

Aims

Treatment 'effects' are often inferred from non-randomized and observational studies. These studies have inherent biases and limitations, which may make therapeutic inferences based on their results unreliable. We compared the conflicting findings of these studies to those of prospective randomized controlled trials (RCTs) in relation to pharmacological treatments for heart failure (HF).

Methods and results

We searched Medline and Embase to identify studies of the association between non-randomized drug therapy and all-cause mortality in patients with HF until 31 December 2017. The treatments of interest were: angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, mineralocorticoid receptor antagonists (MRAs), statins, and digoxin. We compared the findings of these observational studies with those of relevant RCTs. We identified 92 publications, reporting 94 non-randomized studies, describing 158 estimates of the 'effect' of the six treatments of interest on all-cause mortality, i.e. some studies examined more than one treatment and/or HF phenotype. These six treatments had been tested in 25 RCTs. For example, two pivotal RCTs showed that MRAs reduced mortality in patients with HF with reduced ejection fraction. However, only one of 12 non-randomized studies found that MRAs were of benefit, with 10 finding a neutral effect, and one a harmful effect.

Conclusion

This comprehensive comparison of studies of non-randomized data with the findings of RCTs in HF shows that it is not possible to make reliable therapeutic inferences from observational associations. While trials undoubtedly leave gaps in evidence and enrol selected participants, they clearly remain the best guide to the treatment of patients.

Effects of carvedilol therapy in patients with heart failure with preserved ejection fraction - Results from the Croatian heart failure (CRO-HF) registry

BACKGROUND AND OBJECTIVE

According to recent guidelines, the best approach for treatment of heart failure patients with preserved ejection function is still not defined. The aim of this study was to investigate how carvedilol therapy influences the survival rate, ejection fraction and NYHA class in these patients.

PATIENTS AND METHODS

We conducted study on heart failure patients with preserved systolic function from the Croatian heart failure registry who were hospitalized in the period between 2005 and 2010. We enrolled patients with carvedilol listed as treatment on their discharge letters and patients who had been using carvedilol for at least 4 years, while for the control group we selected patients with no beta-blockers on their discharge letters (113 vs 204 respectively). The primary outcome was the overall survival rate and the secondary outcome was the change in ejection fraction of the left ventricle and NYHA class during the study.

RESULTS

Patients in the carvedilol group had a higher overall survival rate compared to patients in the control group (chi-square=14.1, P<0.001). Patients in the carvedilol group in two measurements had a significantly higher ejection fraction compared to the control group (F=148.04, P<0.001). Also, patients in the carvedilol group showed improvement in NYHA class (chi-square=29.768, P<0.001).

CONCLUSION

Long term carvedilol therapy appears to be associated with a higher overall survival rate, improvement in ejection fraction and NYHA class in heart failure patients with preserved ejection fraction.

The effect of beta-blockers on mortality in heart failure with preserved ejection fraction: A meta-analysis of observational cohort and randomized controlled studies

BACKGROUND

Nearly half of patients with heart failure (HF) have preserved ejection fraction (EF) and the mortality of patients with HF with preserved EF (HFpEF) is high. However, there is no therapy to improve survival in HFpEF. Although observational cohort studies (OCSs) have examined the survival benefit of beta-blockers in HFpEF, the results are inconsistent due to limited power with small sample sizes and/or lack of adjustment for known confounders. Furthermore, recent randomized controlled trial (RCT)s failed to show the mortality benefit of beta-blockers in HFpEF. However, these RCTs were not adequately powered and thus the definite conclusion cannot be drawn.

METHODS AND RESULTS

We aimed to conduct a meta-analysis of the effect of beta-blockers on mortality in HFpEF. The search of electronic databases identified 5 OCSs with propensity score (PS) analysis (12,315 patients), 6 OCSs without PS analysis (15,275 patients), and 3 RCTs (1046 patients). Beta-blocker use was associated with improved survival in the pooled analysis of OCSs with PS analysis (RR [95% CI]=0.79 [0.66-0.95]) and in that of OCSs without PS analysis (0.70 [0.52-0.94]). In the pooled analysis of RCTs, beta-blocker use was associated with non-significant reduced risk for mortality (RR [95% CI]=0.80 [0.61-1.05]). Overall, use of beta-blockers reduced the risk of mortality by 21% (RR [95% CI]=0.79 [0.71-0.88]).

CONCLUSION

Our meta-analysis suggests the potential mortality benefit of beta-blockers in HFpEF. Well-designed and powered RCTs should be planned to confirm our observed potential survival benefit of beta-blockers in HFpEF.

Comparative effects of nebivolol and carvedilol on left ventricular diastolic function in older heart failure patients with preserved ejection fraction: study protocol for a randomized controlled trial

Background

Heart failure (HF) is a common and disabling condition in older people. Randomized clinical trials and meta-analyses have clearly demonstrated that the long-term use of β-Blockers improves the outcome of patients with HF. However, limited data are available on the treatment of older HF patients with preserved ejection fraction (EF). No study has specifically compared the relative effectiveness of carvedilol and nebivolol in treating HF in older patients with preserved EF.

Method/design

This trial is a prospective, randomized, open-label, single-centre, active controlled study designed to investigate the effects of nebivolol and carvedilol on diastolic function of the left ventricle (LV) in older HF patients with preserved EF.

We will test the hypothesis that nebivolol improves LV diastolic function to a greater extent than carvedilol in patients over 70 years of age. The study population includes 62 older patients newly diagnosed with HF. Patients will be included in the study if they have a LVEF ≥40 %, New York Heart Association (NYHA) functional classes I, II or III status, and have been clinically stable without hospital admission for HF in the preceding 3 months. Eligible patients will be randomly assigned, in a 1:1 ratio, to receive a loading and maintenance dose of either nebivolol or carvedilol. Echocardiographic evaluations will be performed at baseline, 6, and 12 months after therapy. Clinical assessment and laboratory tests are to be performed at fixed times.

Discussion

This trial is a single-center study that aims to evaluate the impact of nebivolol on LV diastolic function. The results of the study will provide information about the optimal choice of a β-Blocker in the management of patients after diagnosis of HF with preserved EF. The results will be available by 2017.

Trial registration

ClinicalTrials.gov Identifier: NCT02619526, registered on 25 November 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1656-y) contains supplementary material, which is available to authorized users.

Exercise training-induced modification in autonomic nervous system: An update for cardiac patients

Patients with cardiovascular disease show autonomic dysfunction, including sympathetic activation and vagal withdrawal, which leads to fatal events. This review aims to place sympathovagal balance as an essential element to be considered in management for cardiovascular disease patients who benefit from a cardiac rehabilitation program. Many studies showed that exercise training, as non-pharmacologic treatment, plays an important role in enhancing sympathovagal balance and could normalize levels of markers of sympathetic flow measured by microneurography, heart rate variability or plasma catecholamine levels. This alteration positively affects prognosis with cardiovascular disease. In general, cardiac rehabilitation programs include moderate-intensity and continuous aerobic exercise. Other forms of activities such as high-intensity interval training, breathing exercises, relaxation and transcutaneous electrical stimulation can improve sympathovagal balance and should be implemented in cardiac rehabilitation programs. Currently, the exercise training programs in cardiac rehabilitation are individualized to optimize health outcomes. The sports science concept of the heart rate variability (HRV)-vagal index used to manage exercise sessions (for a goal of performance) could be implemented in cardiac rehabilitation to improve cardiovascular fitness and autonomic nervous system function.

Myocardial reverse remodeling: how far can we rewind?

Heart failure (HF) is a systemic disease that can be divided into HF with reduced ejection fraction (HFrEF) and with preserved ejection fraction (HFpEF). HFpEF accounts for over 50% of all HF patients and is typically associated with high prevalence of several comorbidities, including hypertension, diabetes mellitus, pulmonary hypertension, obesity, and atrial fibrillation. Myocardial remodeling occurs both in HFrEF and HFpEF and it involves changes in cardiac structure, myocardial composition, and myocyte deformation and multiple biochemical and molecular alterations that impact heart function and its reserve capacity. Understanding the features of myocardial remodeling has become a major objective for limiting or reversing its progression, the latter known as reverse remodeling (RR). Research on HFrEF RR process is broader and has delivered effective therapeutic strategies, which have been employed for some decades. However, the RR process in HFpEF is less clear partly due to the lack of information on HFpEF pathophysiology and to the long list of failed standard HF therapeutics strategies in these patient's outcomes. Nevertheless, new proteins, protein-protein interactions, and signaling pathways are being explored as potential new targets for HFpEF remodeling and RR. Here, we review recent translational and clinical research in HFpEF myocardial remodeling to provide an overview on the most important features of RR, comparing HFpEF with HFrEF conditions.

Management of chronic heart failure in the older population

Chronic heart failure (CHF) is the leading cause of hospitalization for those over the age of 65 and represents a significant clinical and economic burden. About half of hospital re-admissions are related to co-morbidities, polypharmacy and disabilities associated with CHF. Moreover, CHF also has an enormous cost in terms of poor prognosis with an average one year mortality of 33%–35%. While more than half of patients with CHF are over 75 years, most clinical trials have included younger patients with a mean age of 61 years. Inadequate data makes treatment decisions challenging for the providers. Older CHF patients are more often female, have less cardiovascular diseases and associated risk factors, but higher rates of non-cardiovascular conditions and diastolic dysfunction. The prevalence of CHF with reduced ejection fraction, ischemic heart disease, and its risk factors declines with age, whereas the prevalence of non-cardiac co-morbidities, such as chronic renal failure, dementia, anemia and malignancy increases with age. Diabetes and hypertension are among the strongest risk factors as predictors of CHF particularly among women with coronary heart disease. This review paper will focus on the specific consideration for CHF assessment in the older population. Management strategies will be reviewed, including non-pharmacologic, pharmacologic, quality care indicators, quality improvement in care transition and lastly, end-of-life issues. Palliative care should be an integral part of an interdisciplinary team approach for a comprehensive care plan over the whole disease trajectory. In addition, frailty contributes valuable prognostic insight incremental to existing risk models and assists clinicians in defining optimal care pathways for their patients.

Newest additions to heart failure treatment

INTRODUCTION

Despite the improvement in heart failure (HF) therapy in the last 30 years, this condition remains a major public health concern with high hospitalization and mortality rates, and related costs. Recently, new pharmacological approaches are under evaluation.

AREAS COVERED

For chronic HF with reduced ejection fraction (EF) direct renin inhibitors, neprilysin-angiotensin II receptor inhibitors and aldosterone synthase inhibitors have been tested. For HF with preserved EF, no therapy has been demonstrated up to now to be able to improve patients' outcomes and it remains a substantial unmet need. In acute HF (AHF) new inotropes and vasodilators have been developed and are currently investigated in trials. In this review, mechanism of action and clinical efficacy of new pharmacological approaches on acute and chronic HF will be discussed.

EXPERT OPINION

In patients with HF, some unmet needs remain to be challenged in the near future. For patients with chronic HF, the management of comorbidities, a better definition and treatment of patients with preserved EF are the major issues to be solved. The treatment of patients admitted for AHF is even more compelling. Several hypotheses of research focused on these issues are tested in ongoing trials.

Effects of beta-blockers on heart failure with preserved ejection fraction: a meta-analysis

BACKGROUND

Effects of beta-blockers on the prognosis of the heart failure patients with preserved ejection fraction (HFpEF) remain controversial. The aim of this meta-analysis was to determine the impact of beta-blockers on mortality and hospitalization in the patients with HFpEF.

METHODS

A search of MEDLINE, EMBASE, and the Cochrane Library databases from 2005 to June 2013 was conducted. Clinical studies reporting outcomes of mortality and/or hospitalization for patients with HFpEF (EF ≥ 40%), being assigned to beta-blockers treatment and non-beta-blockers control group were included.

RESULTS

A total of 12 clinical studies (2 randomized controlled trials and 10 observational studies) involving 21,206 HFpEF patients were included for this meta-analysis. The pooled analysis demonstrated that beta-blocker exposure was associated with a 9% reduction in relative risk for all-cause mortality in patients with HFpEF (95% CI: 0.87 - 0.95; P < 0.001). Whereas, the all-cause hospitalization, HF hospitalization and composite outcomes (mortality and hospitalization) were not affected by this treatment (P=0.26, P=0.97, and P=0.88 respectively).

CONCLUSIONS

The beta-blockers treatment for the patients with HFpEF was associated with a lower risk of all-cause mortality, but not with a lower risk of hospitalization. These finding were mainly obtained from observational studies, and further investigations are needed to make an assertion.

Traditional Heart Failure Medications and Sudden Cardiac Death Prevention

Sudden cardiac death (SCD) is still a major public health issue with an estimated annual incidence ranging from 184,000 to > 400,000 per year. The ACC/AHA/ESC 2006 guidelines define SCD as “death from an unexpected circulatory arrest, usually due to a cardiac arrhythmia occurring within an hour of the onset of symptoms”. A recent study of sudden cardiac death using multiple sources of ascertainment found that coronary artery disease was present in more than 50% of patients older than 35 years who died suddenly and underwent autopsy. Antiarrhythmic drugs have failed to show any mortality benefit even when compared to placebo or implantable cardiovertor defibrillators (ICDs). While patients with systolic heart failure are at higher risk of dying suddenly, most of the patients experiencing sudden cardiac death have left ventricular ejection fraction (LVEF) > 50%. β-blockers, Angiotensin enzymes (ACE) inhibitors as well as aldosterone antagonists prevent ischemia and remodelling in the left ventricle especially in post myocardial infarction (MI) patients and in patients with systolic heart failure. This article will review the data on the effects of traditional heart failure medications, especially β-blockers, Renin Angiotensin system blockers, as well as Statin therapy on sudden cardiac death in post MI patients and in patients with systolic heart failure.

Obesity, brain natriuretic peptide levels and mortality in patients hospitalized with heart failure and preserved left ventricular systolic function

BACKGROUND

An inverse relationship between brain natriuretic peptide (BNP) levels and body mass index (BMI) has been described for patients with left ventricular (LV) systolic dysfunction. In this study, the association of BMI, BNP levels and mortality in patients hospitalized for heart failure with preserved LV systolic function (HFpLVF) was investigated.

METHODS

One hundred fifty consecutive patients (98% men) who were hospitalized with HFpLVF and had BNP levels measured on admission were analyzed. Patients were divided into categories of BMI: normal (BMI < 25 kg/m), overweight (BMI 25-29.9 kg/m) and obese (BMI ≥ 30 kg/m). Relevant clinical and echocardiographic characteristics and all-cause mortality were obtained through chart review.

RESULTS

BNP levels were significantly lower in obese (median = 227 pg/mL) and overweight (median = 396 pg/mL) patients compared with those with normal BMI (median = 608 pg/mL, P = 0.003). Higher BMI predicted BNP levels of <100 pg/mL. Compared with patients with normal BMI, overweight and obese patients had a significantly lower risk of total mortality, even after adjusting for other clinical characteristics, including log-transformed BNP levels, atrial fibrillation, the use of beta-blockers at discharge, age, hemoglobin levels and the presence of pulmonary congestion on admission. Higher BNP levels also independently predicted mortality.

CONCLUSIONS

An inverse relationship between BMI and BNP levels exists in patients hospitalized with HFpLVF. Higher BMI is associated with lower mortality, whereas higher BNP levels predict higher mortality in male patients with HFpLVF. These findings should be confirmed in a larger multicenter setting.

[Heart failure with preserved ejection fraction (diastolic heart failure)]

Diastolic heart failure, which is also called as heart failure with preserved ejection fraction, is a clinical syndrome in which patients have signs and symptoms of heart failure, normal or near normal left ventricular ejection fraction (≥ 50%) and evidence of diastolic dysfunction. Recent epidemiological studies have demonstrated that more than half of all heart failure patients have diastolic heart failure. The syndrome is more common in women than in men and the prevalence increases with age. Patients with diastolic heart failure form a fairly heterogeneous group with complex pathophysiologic mechanisms. The disease is often in association with other comorbidities, such as hypertension, diabetes mellitus or obesity. The diagnosis of diastolic heart failure is best achieved by two-dimensional and Doppler echocardiography, which can detect abnormal myocardial relaxation, decreased compliance and increased filling pressure in the setting of normal left ventricular dimensions and preserved ejection fraction. Unlike heart failure with reduced ejection fraction, there is no such an evidence-based treatment for heart failure with preserved ejection fraction, which would improve clinical outcomes. Thus, pharmacological therapy of diastolic heart failure is based mainly on empiric data, and aims to the normalization of blood pressure, reduction of left ventricular dimensions and increased heart rate, maintenance of normal atrial contraction and treatment of symptoms caused by congestion. Beneficial effects of angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers may be utilized in patients with diastolic dysfunction, especially in those with hypertension. Beta-blockers appear to be useful in lowering heart rate and thereby prolonging left ventricular diastolic filling time, while diuretic therapy is the mainstay of treatment for preventing pulmonary congestion. Nonetheless, treatment of the underlying disease is also an important therapeutic approach. This review summarizes the state of current knowledge with regard to diastolic heart failure.

Effects of carvedilol on heart failure with preserved ejection fraction: the Japanese Diastolic Heart Failure Study (J-DHF)

AIMS

The therapeutic strategy for heart failure with preserved ejection fraction (HFPEF) has not been established. The Japanese Diastolic Heart Failure Study (J-DHF) is a multicentre, prospective, randomized, open, blinded-endpoint trial, designed to assess the effects of carvedilol in HFPEF patients.

METHODS AND RESULTS

A total of 245 patients with heart failure and ejection fraction >40% were randomly assigned into those treated with (carvedilol group, n = 120) and without carvedilol (control group, n = 125). The primary outcome is a composite of cardiovascular death and unplanned hospitalization for heart failure. During a median follow-up of 3.2 years, the primary endpoint occurred in 29 patients in the carvedilol group and in 34 patients in the control group [adjusted hazard ratio (HR) 0.902, 95% confidence interval (CI) 0.546-1.488, P = 0.6854]. Another major composite endpoint, cardiovascular death and unplanned hospitalization for any cardiovascular causes, occurred in 38 patients of the carvedilol group and 52 patients of the control group (HR 0.768, 95% CI 0.504-1.169; P = 0.2178). The target dose of carvedilol was 20 mg/day, but the median prescribed dose was 7.5 mg/day. In the patients treated with standard doses (carvedilol >7.5 mg/day, n = 58), this composite outcome was significantly less than in the controls (HR 0.539, 95% CI 0.303-0.959; P = 0.0356), whereas it was comparable with the controls in the patients treated with carvedilol ≤7.5 mg/day (n = 62, HR 1.070, 95% CI 0.650-1.763; P = 0.7893).

CONCLUSIONS

Carvedilol did not improve prognosis of HFPEF patients overall; however, the standard dose, not the low dose, prescription might be effective. This may facilitate further investigation. UMIN number: C000000318.

Sinus rhythm versus atrial fibrillation in elderly patients with chronic heart failure--insight from the Cardiac Insufficiency Bisoprolol Study in Elderly

BACKGROUND

It has been suggested that patients with chronic HF and atrial fibrillation (AF) may respond differently to beta-blockers than those in sinus rhythm (SR).

METHODS

In this predefined analysis of the CIBIS-ELD trial, a total of 876 chronic HF patients (164 patients with AF) were randomized to bisoprolol or carvedilol. During the 12-week-treatment phase, beta-blockers were doubled fortnightly up to the target dose or maximally tolerated dose, which was maintained for 4 weeks.

RESULTS

Patients with AF had lower left ventricular ejection fraction (LVEF), exercise capacity, self-rated health, quality of life (QoL) scores for both SF36 physical and psychosocial component, and higher NYHA class than those in SR. Beta-blocker titration was associated with clinical improvement in both AF and SR patients: LVEF, 6-minute walk distance, physical and psychosocial components of QoL scores, self-rated health and NYHA class (p<0.05, for all). The extent of improvement did not differ between patients with AF and in SR and did not differ between bisoprolol and carvedilol. Heart rate (HR) at baseline was higher in the AF group, and remained higher until the end of the trial. Patients with higher baseline HR had larger reductions in HR, regardless of rhythm. AF patients more frequently reached target beta-blocker dose compared to those in SR (p<0.005).

CONCLUSIONS

Elderly patients with chronic HF and AF derive comparable clinical benefits from beta-blocker titration as those in SR. Patients with AF tolerate higher beta-blocker doses than those in SR, which appears to be related to higher baseline HR.

Diagnosis and management of left ventricular diastolic dysfunction in the hypertensive patient

The progression of hypertensive involvement toward heart failure includes myocardial fibrosis and changes of left ventricular (LV) geometry. In the presence of these abnormalities, diastolic abnormalities occur and are defined as LV diastolic dysfunction (DD). They include alterations of both relaxation and filling, precede alterations of chamber systolic function and can induce symptoms of heart failure even when ejection fraction is normal. The prevalence of heart failure with normal ejection fraction (HFNEF) increased over time whereas the rate of death from this disorder remained unchanged. In this view, diagnosis, prognosis, and therapeutic management of DD and HFNEF in hypertensive patients is a growing public health problem. DD may be asymptomatic and identified occasionally during a Doppler-echocardiographic examination. This tool has gained, therefore, important clinical position for diagnosis of DD. Comprehensive assessment of diastolic function should be done not by a simple classification of DD progression but by estimating the degree of LV filling pressure (FP), a true determinant of symptoms and prognosis. This can be obtained by different ultrasound maneuvers/tools but the ratio between transmitral E velocity and pulsed tissue Doppler-derived early diastolic velocity (E/e' ratio) is the most feasible and accurate. The identification of left atrial enlargement may be useful in uncertain cases. The recommended management of DD in hypertensive patients should correspond to blood pressure (BP) lowering and to the attempt of reducing LV mass and normalizing LV geometry. Prospective studies with well-defined entry criteria are needed to establish whether this approach could reflect a better prognosis.

Rationale and design of the beta-blocker in heart failure with normal left ventricular ejection fraction (beta-PRESERVE) study

AIMS

Chronic heart failure with normal left ventricular ejection fraction (HFNEF) is not only common, but also carries a high risk of substantial morbidity and mortality. However, few studies have been conducted in this population and no proven treatment is available. Although beta-blockers are evidence-based first-line therapy in systolic heart failure, they have not been well studied in HFNEF.

METHODS

This study is a multicentre, prospective, randomized, open-label, blinded endpoint (PROBE) trial. A total of 1200 patients will be randomized to either beta-blocker (metoprolol succinate) or control (n = 600 per group). The primary endpoint is a composite of hospitalization for heart failure and cardiovascular death. The secondary endpoints include cardiovascular death, heart failure mortality or hospitalization, all-cause mortality, change in New York Heart Association class, change in left ventricular ejection fraction, increase in NT-proBNP (by > or = 50% of the value at randomization), beta-blocker tolerance, and premature termination of beta-blocker therapy due to adverse events. The follow-up period is a minimum of 2 years.

CONCLUSION

This study will provide important evidence, for the first time to our knowledge, of the long-term efficacy of beta-blocker therapy in the management of HFNEF.

Heart failure with preserved ejection fraction: pathophysiology and emerging therapies

Approximately half of patients with heart failure (HF) have a preserved ejection fraction (HFpEF). Morbidity and mortality are similar to HF with reduced EF (HFrEF), yet therapies with unequivocal benefit in HFrEF have not been shown to be effective in HFpEF. Recent studies have shown that the pathophysiology of HFpEF, initially believed to be due principally to diastolic dysfunction, is more complex. Appreciation of this complexity has shed new light into how HFpEF patients might respond to traditional HF treatments, while also suggesting new applications for novel therapies and strategies. In this review, we shall briefly review the pathophysiologic mechanisms in HFpEF, currently available clinical trial data, and finally explore new investigational therapies that are being developed and tested in ongoing and forthcoming trials.

Treatment of heart failure with normal ejection fraction: an inconvenient truth!

Despite use of similar drugs, outcomes of recent heart failure (HF) trials were frequently neutral in heart failure with normal left ventricular ejection fraction (HFNEF) and positive in heart failure with reduced left ventricular ejection fraction (HFREF). The neutral outcomes of HFNEF trials were often attributed to deficient HFNEF patient recruitment with inclusion of many HFREF or noncardiac patients. Patient recruitment criteria of 21 HFNEF trials were therefore reviewed in reference to diagnostic guidelines for HFNEF. In the 4 published sets of guidelines, a definite diagnosis of HFNEF required the simultaneous and obligatory presence of signs and/or symptoms of HF and evidence of normal systolic left ventricular (LV) function and of diastolic LV dysfunction. In 3 of 4 sets of guidelines, normal systolic LV function comprised both a left ventricular ejection fraction (LVEF) >50% and an absence of LV dilation. Among the 21 HFNEF trials, LVEF cutoff values ranged from 35% to 50%, with only 8 trials adhering to an LVEF >50%. Furthermore, only 1 trial specified a normal LV end-diastolic dimension as an enrollment criterion and only 7 trials required evidence of diastolic LV dysfunction. Nonadherence to diagnostic guidelines induced excessive enrollment into HFNEF trials of HF patients with eccentric LV remodeling and ischemic heart disease compared with HF patients with concentric LV remodeling and arterial hypertension. Nonadherence to guidelines also led to underpowered HFNEF trials with a low incidence of outcome events such as death or HF hospitalizations. Future HFNEF trials should therefore adhere to diagnostic guidelines for HFNEF.

Beta-blockade with nebivolol in elderly heart failure patients with impaired and preserved left ventricular ejection fraction: Data From SENIORS (Study of Effects of Nebivolol Intervention on Outcomes and Rehospitalization in Seniors With Heart Failure)

OBJECTIVES

In this pre-specified subanalysis of the SENIORS (Study of Effects of Nebivolol Intervention on Outcomes and Rehospitalization in Seniors With Heart Failure) trial, which examined the effects of nebivolol in elderly heart failure (HF) patients, we explored the effects of left ventricular ejection fraction (EF) on outcomes, including the subgroups impaired EF (< or =35%) and preserved EF (>35%).

BACKGROUND

Beta-blockers are established drugs in patients with HF and impaired EF, but their value in preserved EF is unclear.

METHODS

We studied 2,111 patients; 1,359 (64%) had impaired (< or =35%) EF (mean 28.7%) and 752 (36%) had preserved (>35%) EF (mean 49.2%). The effect of nebivolol was investigated in these 2 groups, and it was compared to explore the interaction of EF with outcome. Follow-up was 21 months; the primary end point was all-cause mortality or cardiovascular hospitalizations.

RESULTS

Patients with preserved EF were more often women (49.9% vs. 29.8%) and had less advanced HF, more hypertension, and fewer prior myocardial infarctions (all p < 0.001). During follow-up, the primary end point occurred in 465 patients (34.2%) with impaired EF and in 235 patients (31.2%) with preserved EF. The effect of nebivolol on the primary end point (hazard ratio [HR] of nebivolol vs. placebo) was 0.86 (95% confidence interval: 0.72 to 1.04) in patients with impaired EF and 0.81 (95% confidence interval: 0.63 to 1.04) in preserved EF (p = 0.720 for subgroup interaction). Effects on all secondary end points were similar between groups (HR for all-cause mortality 0.84 and 0.91, respectively), and no p value for interaction was <0.48.

CONCLUSIONS

The effect of beta-blockade with nebivolol in elderly patients with HF in this study was similar in those with preserved and impaired EF.

Distinct myocardial effects of beta-blocker therapy in heart failure with normal and reduced left ventricular ejection fraction

AIMS

Left ventricular (LV) myocardial structure and function differ in heart failure (HF) with normal (N) and reduced (R) LV ejection fraction (EF). This difference could underlie an unequal outcome of trials with beta-blockers in heart failure with normal LVEF (HFNEF) and heart failure with reduced LVEF (HFREF) with mixed results observed in HFNEF and positive results in HFREF. To investigate whether beta-blockers have distinct myocardial effects in HFNEF and HFREF, myocardial structure, cardiomyocyte function, and myocardial protein composition were compared in HFNEF and HFREF patients without or with beta-blockers.

METHODS AND RESULTS

Patients, free of coronary artery disease, were divided into beta-(HFNEF) (n = 16), beta+(HFNEF) (n = 16), beta-(HFREF) (n = 17), and beta+(HFREF) (n = 22) groups. Using LV endomyocardial biopsies, we assessed collagen volume fraction (CVF) and cardiomyocyte diameter (MyD) by histomorphometry, phosphorylation of myofilamentary proteins by ProQ-Diamond phosphostained 1D-gels, and expression of beta-adrenergic signalling and calcium handling proteins by western immunoblotting. Cardiomyocytes were also isolated from the biopsies to measure active force (F(active)), resting force (F(passive)), and calcium sensitivity (pCa(50)). Myocardial effects of beta-blocker therapy were either shared by HFNEF and HFREF, unique to HFNEF or unique to HFREF. Higher F(active), higher pCa(50), lower phosphorylation of troponin I and myosin-binding protein C, and lower beta(2) adrenergic receptor expression were shared. Higher F(passive), lower CVF, lower MyD, and lower expression of stimulatory G protein were unique to HFNEF and lower expression of inhibitory G protein was unique to HFREF.

CONCLUSION

Myocardial effects unique to either HFNEF or HFREF could contribute to the dissimilar outcome of beta-blocker therapy in both HF phenotypes.

Heart failure with normal left ventricular ejection fraction: what is the evidence?

Heart failure with a normal ejection fraction (HFNEF) is a common clinical problem with many unsolved questions regarding pathophysiology, diagnosis, and therapy. Although the term diastolic heart failure has been abandoned, diastolic left ventricular (LV) dysfunction together with combined systolic ventricular and arterial stiffening are considered to be the main pathophysiologic mechanisms in HFNEF. Current guidelines define HFNEF by symptoms or signs of heart failure in the presence of LV ejection fraction of more than 50%, but with additional evidence of LV diastolic dysfunction. Definite diagnosis of HFNEF requires exclusion of valvular heart disease, constrictive pericarditis, and several noncardiac diseases. Echocardiographic assessment of the tissue Doppler-derived filling index E/E', which is the ratio of the peak early mitral valve flow velocity to the peak early diastolic mitral annular velocity, should improve the noninvasive estimation of filling pressures in suspected HFNEF. Elevated plasma levels of natriuretic peptides may confirm HFNEF if tissue Doppler echocardiography is inconclusive. Treatment of HFNEF is symptom oriented and mainly based on pathophysiologic assumptions such as heart rate reduction, blood pressure control, and maintenance of sinus rhythm. In contrast to heart failure with reduced ejection fraction, large-scale randomized controlled drug trials for HFNEF are scarce and could not demonstrate mortality reduction so far.

Treatment of hypertension in heart failure with preserved ejection fraction: role of the kidney

Heart failure can present clinically as primarily diastolic or systolic dysfunction or both. There is an increasing awareness that heart failure can occur in the presence of a normal left ventricular ejection fraction. Heart failure with normal left ventricular ejection fraction is frequently referred to as diastolic heart failure because of the presence of diastolic left ventricular dysfunction evident from impaired left ventricular relaxation. This article focuses on the treatment of hypertension and the role the kidney plays in selecting appropriate agents.

Treatment of heart failure with preserved systolic function

Heart failure is a major public health problem. Heart failure with preserved systolic function (HF-PSF) is a common form, which is difficult to diagnose. Results of recent studies show that HF-PSF has a poor prognosis, with an annual survival rate similar to that of heart failure with left ventricular systolic dysfunction. Despite these findings, the therapeutic management of HF-PSF is not clearly defined. We will discuss in this review of the literature the current therapeutic management of HF-PSF, including the role of precipitating factors such as hypertension, myocardial ischaemia and supraventricular arrhythmias, and the main results of epidemiological registries and randomized controlled clinical trials in this disease. Only four large therapeutic trials have assessed the impact of different classes of drugs (digoxin, angiotensin II converting enzyme inhibitors, angiotensin II receptors type I blockers and beta-blockers) on morbidity and mortality in HF-PSF. Results of these trials are disappointing. Apart from the beta-blockers, the other three classes of drugs did not show benefit on the outcome of the disease. Moreover, the results of the beta-blocker trial are controversial as a mixed population of heart failure with and without preserved systolic function was studied. Finally, the current therapeutic management of patients with HF-PSF is still based on our pathophysiological knowledge: education, low salt diet, diuretics, slowing heart rate and controlling triggering factors. Other large randomized controlled multicenter trials, which may help us in the understanding of HF-PSP and its therapeutic management, are ongoing.

Heart failure is not a diagnosis

Heart failure (HF) is a syndrome and not a diagnosis. Aetiology and precipitants for decompensation are often not sought. Care is also often based upon protocols, with widespread prescription of drugs validated in systolic HF, for patients with other forms of HF for example HF with preserved ejection fraction which can account for almost half of patients with HF in the UK. Therefore, service design and configuration by healthcare providers should based upon quality and not only feasibility, as protocol-based treatment will inevitably diminish the quality of care for patients with HF and result in both inappropriate care in many cases as well as reduced access to advanced evidence based and NICE approved therapies. Expertise is therefore of paramount importance in managing patients with HF.

Tolerability and dose-related effects of nebivolol in elderly patients with heart failure: data from the Study of the Effects of Nebivolol Intervention on Outcomes and Rehospitalisation in Seniors with Heart Failure (SENIORS) trial

BACKGROUND

The SENIORS trial showed that nebivolol reduced the risk of death or cardiovascular (CV) hospitalization in elderly patients with heart failure (HF). We aimed to assess tolerability and dose-related effects of the beta-blocker nebivolol in elderly patients from the SENIORS trial.

METHODS

Patients assigned to nebivolol (n = 1031) were classified into 4 groups, according to the dose achieved at the end of titration phase (maintenance dose): 0 mg (n = 74), low dose (1.25 or 2.5 mg, n = 142), medium dose (5 mg, n = 127), and target dose (10 mg, n = 688) and compared with those allocated to placebo (n = 1030). Age, sex and ejection fraction were similar between the groups, but prior myocardial infarction, coronary revascularization, and serum creatinine levels were lower in patients who achieved higher maintenance doses of nebivolol.

RESULTS

After adjustment, all-cause mortality or CV hospitalization was significantly reduced in the 10 mg dose group compared with placebo (hazard ratio [HR] 0.75, 95% CI 0.63-0.90) which was similar to the medium dose group (HR 0.73, 95% CI 0.52-1.02). The low dose group had an apparently lower benefit (HR 0.88, 95% CI 0.64-1.20), whereas patients unable to tolerate any dose of nebivolol had an increased risk of death or CV hospitalization (HR 1.95, 95% CI 1.38-2.75).

CONCLUSIONS

The benefits of nebivolol in elderly patients with HF appear to be related to the maintenance dose achieved. Patients unable to tolerate any dose have the worst prognosis.