Heart Rate and Heart Failure With Preserved Ejection Fraction: Time to Slow β-Blocker Use?

Percent Predicted Peak Exercise Oxygen Pulse Provides Insights Into Ventricular-Vascular Response and Prognosticates HFpEF

Background

Peak oxygen consumption and oxygen pulse along with their respective percent predicted measures are gold standards of exercise capacity. To date, no studies have investigated the relationship between percent predicted peak oxygen pulse (%PredO2P) and ventricular-vascular response (VVR) and the association of %PredO2P with all-cause mortality in heart failure with preserved ejection fraction (HFpEF) patients.

Objectives

The authors investigated the association between: 1) CPET measures of %PredO2P and VVR; and 2) %PredO2P and all-cause mortality in HFpEF patients.

Methods

Our cohort of 154 HFpEF patients underwent invasive CPET and were grouped into %PredO2P tertiles. The association between percent predicted Fick components and markers of VVR (ie, proportionate pulse pressure, effective arterial elastance) was determined with correlation analysis. The Cox proportional hazards model was used to identify predictors of mortality.

Results

The participants' mean age was 57 ± 15 years. Higher %PredO2P correlated with higher exercise capacity. In terms of VVR, higher %PredO2P correlated with a lower pressure for a given preload (effective arterial elastance r = -0.45, P < 0.001 and proportionate pulse pressure r = -0.22, P = 0.008). %PredO2P distinguished normal and abnormal percent predicted peak stroke volume and correlated positively with %PredVO2 (r = 0.61, P < 0.001). Participants had a median follow-up time of 5.6 years and 15% death. Adjusted for age and body mass index, there was a 5% relative reduction in mortality (HR: 0.95, 95% CI: 0.92-0.98, P = 0.003) for every percent increase in %PredO2P.

Conclusions

In HFpEF, %PredO2P is a VVR marker that can stratify invasive parameters such as percent predicted peak stroke volume. %PredO2P is an independent prognostic marker for all-cause mortality and those with higher %PredO2P exhibited longer survival.

Differences in the Effects of Beta-Blockers Depending on Heart Rate at Discharge in Patients With Heart Failure With Preserved Ejection Fraction and Atrial Fibrillation

Background and Objectives

Beta-blockers (BBs) improve prognosis in heart failure (HF), which is mediated by lowering heart rate (HR). However, HR has no prognostic implication in atrial fibrillation (AF) and also BBs have not been shown to improve prognosis in heart failure with preserved ejection fraction (HFpEF) with AF. This study assessed the prognostic implication of BB in HFpEF with AF according to discharge HR.

Methods

From the Korean Acute Heart Failure Registry, 687 patients with HFpEF and AF were selected. Study subjects were divided into 4 groups based on 75 beats per minute (bpm) of HR at discharge and whether or not they were treated with BB at discharge.

Results

Of the 687 patients with HFpEF and AF, 128 (36.1%) were in low HR group and 121 (36.4%) were in high HR group among those treated with BB at discharge. In high HR group, HR at discharge was significantly faster in BB non-users (85.5±9.1 bpm vs. 89.2±12.5 bpm, p=0.005). In the Cox model, BB did not improve 60-day rehospitalization (hazard ratio, 0.93; 95% confidence interval [95% CI], 0.35-2.47) or mortality (hazard ratio, 0.77; 95% CI, 0.22-2.74) in low HR group. However, in high HR group, BB treatment at discharge was associated with 82% reduced 60-day HF rehospitalization (hazard ratio, 0.18; 95% CI, 0.04-0.81), but not with mortality (hazard ratio, 0.77; 95% CI, 0.20-2.98).

Conclusions

In HFpEF with AF, in patients with HR over 75 bpm at discharge, BB treatment at discharge was associated with a reduced 60-day rehospitalization rate.

Heart Rate at Rest and Incident Atrial Fibrillation in Patients With Diastolic Dysfunction

Diastolic dysfunction (DD) is associated with incident atrial fibrillation (AF). The influence of heart rate at rest (RHR) on incident AF in patients with DD has not been investigated. The goal of this study is to assess the influence of RHR on incident AF in patients with DD. Patients from a large health system with no previous history of AF, a left ventricular ejection fraction ≥50%, and documented DD on echocardiography were divided into quartiles (<66, 66 to 76, 77 to 91, >91 beats per minute) based on RHR. Incident AF was estimated using AF hospitalization during follow-up. Hazard ratios (HR) for AF hospitalization and all-cause death were calculated with a Cox proportional hazards model. A total of 19,046 patients were analyzed. Over a median follow-up of 42.2 months, 742 (3.9%) patients were hospitalized for AF. Both slower and faster RHR were associated with increased risk of AF hospitalization (HR 1.40, confidence interval [CI] 1.14 to 1.71, p = 0.001, HR 1.23, CI 0.99 to 1.53, p = 0.06 and HR 1.72, CI 1.38 to 2.14, p <0.001, for quartiles 1, 2, and 4, respectively), suggesting a J-shaped relation. Progressive increase in all-cause death was noted with faster RHR (HR1.19 per quartile increase, CI 1.16 to 1.22, p <0.001). These results persisted after adjustment for age, cardiovascular co-morbidities, grade of DD, and β-blocker use. In conclusion, this large, real-world analysis indicates increased risk of incident AF with slower and faster RHR in patients with DD. Randomized trials are needed to evaluate the potential of RHR modification to mitigate the risk of incident AF.

Prognostic significance of left atrial strain combined with left ventricular strain using cardiac magnetic resonance feature tracking in patients with heart failure with preserved ejection fraction

We aimed to evaluate the prognostic value of left ventricular global longitudinal strain (LVGLS) and left atrial strain (LAS) obtained from magnetic resonance imaging (MRI) feature tracking in patients with heart failure with preserved ejection fraction (HFpEF). We retrospectively enrolled consecutive patients with HFpEF admitted to our hospital who underwent cardiac MRI. LVGLS and LAS were obtained from cine MRI by feature tracking. The end point was defined as a composite of all-cause death, myocardial infarction, and hospitalization due to decompensated HF. One-hundred patients with HFpEF were enrolled. Mean LVGLS and LAS were - 13.7 ± 3.7% and 22.5 ± 11.6%, respectively. During follow-up of 4.4 ± 1.9 years, 24 events occurred. Multivariate Cox proportional hazards model analysis demonstrated LAS was independently associated with adverse cardiac events. Kaplan-Meier curve analysis revealed that the patients with both LVGLS and LAS worse than the median (LVGLS ≥ - 12.2% and LAS ≤ 13.8%) had a significantly lower event-free rate compared to those with preserved strain (Log-rank P < 0.001). Simultaneous assessment of LVGLS and LAS using MRI was useful for risk stratification in the patients with HFpEF.

How to Manage Beta-Blockade in Older Heart Failure Patients: A Scoping Review

Beta blockers (BBs) play a crucial role in enhancing the quality of life and extending the survival of patients with heart failure and reduced ejection fraction (HFrEF). Initiating the therapy at low doses and gradually titrating the dose upwards is recommended to ensure therapeutic efficacy while mitigating potential adverse effects. Vigilant monitoring for signs of drug intolerance is necessary, with dose adjustments as required. The management of older HF patients requires a case-centered approach, taking into account individual comorbidities, functional status, and frailty. Older adults, however, are often underrepresented in randomized clinical trials, leading to some uncertainty in management strategies as patients with HF in clinical practice are older than those enrolled in trials. The present article performs a scoping review of the past 25 years of published literature on BBs in older HF patients, focusing on age, outcomes, and tolerability. Twelve studies (eight randomized-controlled and four observational) encompassing 26,426 patients were reviewed. The results indicate that BBs represent a viable treatment for older HFrEF patients, offering benefits in symptom management, cardiac function, and overall outcomes. Their role in HF with preserved EF, however, remains uncertain. Further research is warranted to refine treatment strategies and address specific aspects in older adults, including proper dosing, therapeutic adherence, and tolerability.

β-Blocker Withdrawal and Functional Capacity Improvement in Patients With Heart Failure With Preserved Ejection Fraction

Importance

Increasing the patient's heart rate (HR) has emerged as a therapeutic option in patients with heart failure with preserved ejection fraction (HFpEF). However, the evidence is conflicting, and the profile of patients who benefit most from this strategy remains unclear.

Objective

To assess the association of β-blocker treatment withdrawal with changes in the percentage of predicted peak oxygen consumption (VO2) across indexed left ventricular diastolic (iLVEDV) and indexed left ventricular systolic volumes (iLVESV), and left ventricular ejection fraction (LVEF) in patients with HFpEF and chronotropic incompetence.

Design, Setting, and Participants

This post hoc analysis was conducted using data from the investigator-blinded multicenter, randomized, and crossover clinical trial, PRESERVE-HR, that took place from October 1, 2018, through December 31, 2020, to investigate the short-term effects (2 weeks) of β-blocker withdrawal on peak oxygen consumption (peak VO2). Patients with stable HFpEF (New York Heart Association functional class II to III) receiving treatment with β-blocker and chronotropic incompetence were included.

Intervention

Participants in the PRESERVE-HR trial were randomized to withdraw vs continue with β-blocker treatment. After 2 weeks, they were crossed over to receive the opposite intervention. This crossover randomized clinical trial examined the short-term effect of β-blocker withdrawal on peak VO2.

Main Outcomes and Measures

The primary outcome was to evaluate the association between β-blocker withdrawal and short-term changes in percentage of peak VO2 across iLVEDV, iLVESV, and LVEF in patients with HFpEF and chronotropic incompetence treated with β-blocker.

Results

A total of 52 patients (mean age, 73 [SD, 13] years; 60% female) were randomized. The mean resting HR, peak HR, peak VO2, and percentage of peak VO2 were 65 (SD, 9) beats per minute (bpm), 97 (SD, 15) bpm, 12.4 (SD, 2.9) mL/kg per minute, and 72.4% (SD, 17.7%), respectively. The medians (minimum-maximum) of iLVEDV, iLVESV, and LVEF were 44 mL/m2 (IQR, 19-82), 15 mL/m2 (IQR, 7-32), and 64% (IQR, 52%-78%), respectively. After stopping β-blocker treatment, the median increase in peak HR was plus 30 bpm (95% CI, 25-35; P < .001). β-Blocker cessation was differentially associated with change of percentage of peak VO2 across the continuum of iLVESV (P for interaction = .02), indicating a greater benefit in those with lower iLVESV.

Conclusions and Relevance

In this study, results showed that in patients with HFpEF and chronotropic incompetence receiving treatment with β-blocker, lower iLVESV may identify those with a greater short-term improvement in maximal functional capacity after stopping β-blocker treatment. Further studies are warranted for further investigation.

Trial Registration

ClinicalTrials.gov (NCT03871803).

Impact of heart rate changes during hospitalization on outcome in heart failure with preserved ejection fraction

AIMS

The benefits of lowering heart rate (HR) in heart failure (HF) with preserved ejection fraction (HFpEF) patients are still a matter of debate. This study aimed to investigate the relationship between changes in HR during hospitalization and cardiovascular (CV) events and all-cause death in hospitalized HFpEF patients.

METHODS AND RESULTS

Hospitalized HF patients between January 2017 and December 2021 were consecutively enrolled in a national, multicentred, and prospective registry database, the China Cardiovascular Association Database-HF Center Registry. HF patients with a left ventricular ejection fraction of ≥50% were defined as HFpEF patients. The study analysed admission/discharge HR, change in HR during hospitalization (∆HR), and ∆HR ratio (∆HR/admission HR). The patients were categorized into three groups: no HR dropping group (ΔHR ratio > 0.0%), moderate HR dropping group (-15% < ΔHR ratio ≤ 0.0%), and excessive HR dropping group (ΔHR ratio ≤ -15%). All patients were followed up for 12 months. The primary endpoint was CV events (CV death or HF rehospitalization). The secondary endpoint was all-cause death. A total of 19 510 HFpEF patients (9750 males, mean age 71.9 ± 12.2 years) were included, with 4575 in the no HR dropping group, 8434 in the moderate HR dropping group, and 6501 in the excessive HR dropping group. Excessive HR dropping during hospitalization was significantly associated with an increased risk of CV events (17.1%) compared with the no HR dropping group (14.5%, P < 0.001) or the moderate HR dropping group (14.0%, P < 0.001), although all-cause mortality was similar among the three groups. After adjusting for multiple confounding factors, excessive HR dropping remained an independent predictor of increased CV event risk [hazard ratio 1.197, 95% confidence interval (CI) 1.078-1.328]. Subgroup analysis revealed that the prognostic impact of excessive HR dropping on increased CV event risk remained in the subgroups of older age, New York Heart Association class IV, ischaemic HF, higher left ventricular ejection fraction, absence of chronic kidney disease, and use of beta-blockers or ivabradine. Independent determinants associated with excessive HR dropping during admission included use of beta-blockers [odds ratio (OR) 1.683, 95% CI 1.558-1.819], lower discharge diastolic blood pressure (OR 0.988, 95% CI 0.985-0.991), no pacemaker (OR 0.501, 95% CI 0.416-0.603), coexisting atrial fibrillation or atrial flutter (OR 1.327, 95% CI 1.218-1.445), and use of digoxin (OR 1.340, 95% CI 1.213-1.480).

CONCLUSIONS

In hospitalized HFpEF patients, excessive HR dropping during hospitalization is associated with an increased risk of CV death or HF rehospitalization. These findings highlight the importance of HR monitoring and avoiding excessively slowing down HR in hospitalized HFpEF patients to reduce the risk of CV events.

Advance in the pharmacological and comorbidities management of heart failure with preserved ejection fraction: evidence from clinical trials

The prevalence of heart failure with preserved ejection fraction (HFpEF) accounts for approximately 50% of the total heart failure population, and with the aging of the population and the increasing prevalence of hypertension, obesity, and type 2 diabetes (T2DM), the incidence of HFpEF continues to rise and has become the most common subtype of heart failure. Compared with heart failure with reduced ejection fraction, HFpEF has a more complex pathophysiology and is more often associated with hypertension, T2DM, obesity, atrial fibrillation, renal insufficiency, pulmonary hypertension, obstructive sleep apnea, and other comorbidities. HFpEF has generally been considered a syndrome with high phenotypic heterogeneity, and no effective treatments have been shown to reduce mortality to date. Diuretics and comorbidity management are traditional treatments for HFpEF; however, they are mostly empirical due to a lack of clinical evidence in the setting of HFpEF. With the EMPEROR-Preserved and DELIVER results, sodium-glucose cotransporter 2 inhibitors become the first evidence-based therapies to reduce rehospitalization for heart failure. Subgroup analyses of the PARAGON-HF, TOPCAT, and CHARM-Preserved trials suggest that angiotensin receptor-neprilysin inhibitors, spironolactone, and angiotensin II receptor blockers may be beneficial in patients at the lower end of the ejection fraction spectrum. Other potential pharmacotherapies represented by non-steroidal mineralocorticoid receptor antagonists finerenone and antifibrotic agent pirfenidone also hold promise for the treatment of HFpEF. This article intends to review the clinical evidence on current pharmacotherapies of HFpEF, as well as the comorbidities management of atrial fibrillation, hypertension, T2DM, obesity, pulmonary hypertension, renal insufficiency, obstructive sleep apnea, and iron deficiency, to optimize the clinical management of HFpEF.

Effects of Continuous Accelerated Pacing on Cardiac Structure and Function in Patients With Heart Failure With Preserved Ejection Fraction: Insights From the myPACE Randomized Clinical Trial

BACKGROUND

Heart failure with preserved ejection fraction ≥50% is prevalent with few evidence-based therapies. In a trial of patients with heart failure with preserved ejection fraction with specialized pacemakers, treatment with accelerated personalized pacing averaging 75 bpm (myPACE) markedly improved quality of life, NT-proBNP (N-terminal pro-brain natriuretic peptide), physical activity, and atrial fibrillation burden compared with the standard lower rate setting of 60 bpm (usual care).

METHODS AND RESULTS

In this exploratory study, provider-initiated echocardiographic studies obtained before and after the trial were assessed for changes in left ventricular (LV) structure and function among participants who continued their pacing assignment. The analytic approach aimed to detect differences in standard and advanced echocardiographic parameters within and between study arms. Of the 100 participants, 16 myPACE and 20 usual care arm had a qualifying set of echocardiograms performed a mean (SD) 3 (2.0) years apart. Despite similar baseline echocardiogram measures, sustained exposure to moderately accelerated pacing resulted in reduced septal wall thickness (in cm: myPACE 1.1 [0.2] versus usual care 1.2 [0.2], P=0.008) and lower LV mass to systolic volume ratio (in g/mL: myPACE 4.8 [1.9] versus usual care 6.8 [3.1], P=0.038) accompanied by a minor reduction in LV ejection fraction (in %: myPACE 55 [5] versus usual care 60 [5], P=0.015). These changes were paralleled by improvements in heart failure-related quality of life (myPACE Minnesota Living with Heart Failure Questionnaire improved by 16.1 [13.9] points, whereas usual care worsened by 6.9 [11.6] points, P<0.001). Markers of diastolic function and LV performance were not affected.

CONCLUSIONS

Exposure to continuous accelerated pacing in heart failure with preserved ejection fraction is associated with a reduced LV wall thickness and a small amount of LV dilation with small reduction in ejection fraction.

Coagulation Disorders and Thrombotic Complications in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is associated with multiple cardiovascular and noncardiovascular comorbidities and risk factors which increase the risk of thrombotic complications, such as atrial fibrillation, chronic kidney disease, arterial hypertension and type 2 diabetes mellitus. Subsequently, thromboembolic risk stratification in this population poses a great challenge. Since date from the large randomized clinical trials mostly include both patients with truly preserved EF, and those with heart failure with mildly reduced ejection fraction, there is an unmet need to characterize the patients with truly preserved EF. Considering the significant evidence gap in this area, we sought to describe the coagulation disorders and thrombotic complications in patients with HFpEF and discuss the specific thromboembolic risk factors in patients with HFpEF, with the goal to tailor risk stratification to an individual patient.

Effect of paced heart rate on quality of life and natriuretic peptides for stage B or C heart failure with preserved ejection fraction: A secondary analysis of the myPACE trial

AIM

Emerging evidence suggests a beneficial effect of higher heart rates in some patients with heart failure with preserved ejection fraction (HFpEF). This study aimed to evaluate the impact of higher backup pacing rates in HFpEF patients with preexisting pacemaker systems that limit pacemaker-mediated dyssynchrony across left ventricular (LV) volumes and LV ejection fraction (LVEF).

METHODS AND RESULTS

This is a post-hoc analysis of the myPACE clinical trial that evaluated the effects of personalized accelerated pacing setting (myPACE) versus standard of care on changes in Minnesota Living with Heart Failure Questionnaire (MLHFQ) score, N-terminal pro-brain natriuretic peptide (NT-proBNP), pacemaker-detected activity levels, and atrial fibrillation (AF) burden in patients with HFpEF with preexisting pacemakers. Between-treatment comparisons were performed using linear regression models adjusting for the baseline value of the exposure (ANCOVA design). This study included 93 patients with pre-trial transthoracic echocardiograms available (usual care n = 49; myPACE n = 44). NT-proBNP levels and MLHFQ scores improved in a higher magnitude in the myPACE group at lower indexed LV end-diastolic volumes (iLVEDV) (NT-proBNP-iLVEDV interaction p = 0.006; MLHFQ-iLVEDV interaction p = 0.068). In addition, personalized accelerated pacing led to improved changes in activity levels and NT-proBNP, especially at higher LVEF (activity levels-LVEF interaction p = 0.009; NT-proBNP-LVEF interaction p = 0.058). No evidence of heterogeneity was found across LV volumes or LVEF for pacemaker-detected AF burden.

CONCLUSIONS

In the post-hoc analysis of the myPACE trial, we observed that the benefits of a personalized accelerated backup pacing on MLHFQ score, NT-proBNP, and pacemaker-detected activity levels appear to be more pronounced in patients with smaller iLVEDV and higher LVEF.

Histamine H2 receptor antagonist exhibited comparable all-cause mortality-decreasing effect as β-blockers in critically ill patients with heart failure: a cohort study

Background: Our previous study reported that histamine H2 receptor antagonists (H2RAs) exposure was associated with decreased mortality in critically ill patients with heart failure (HF) through the same pharmacological mechanism as β-blockers. However, population-based clinical study directly comparing the efficacy of H2RAs and β-blockers on mortality of HF patients are still lacking. This study aims to compare the association difference of H2RAs and β-blockers on mortality in critically ill patients with HF using the Medical Information Mart for Intensive Care III database (MIMIC-III). Methods: Study population was divided into 4 groups: β-blockers + H2RAs group, β-blockers group, H2RAs group, and Non-β-blockers + Non-H2RAs group. Kaplan-Meier curves and multivariable Cox regression models were employed to evaluate the differences of all-cause mortalities among the 4 groups. Propensity score matching (PSM) was used to increase comparability of four groups. Results: A total of 5593 patients were included. After PSM, multivariate analyses showed that patients in H2RAs group had close all-cause mortality with patients in β-blockers group. Furthermore, 30-day, 1-year, 5-year and 10-year all-mortality of patients in β-blockers + H2RAs group were significantly lower than those of patients in β-blockers group, respectively (HR: 0.64, 95%CI: 0.50-0.82 for 30-day; HR: 0.80, 95%CI: 0.69-0.93 for 1-year mortality; HR: 0.83, 95%CI: 0.74-0.93 for 5-year mortality; and HR: 0.85, 95%CI: 0.76-0.94 for 10-year mortality, respectively). Conclusion: H2RAs exposure exhibited comparable all-cause mortality-decreasing effect as β-blockers; and, furthermore, H2RAs and β-blockers had additive or synergistic interactions to improve survival in critically ill patients with HF.

Personalized accelerated physiologic pacing

Heart failure with preserved ejection fraction (HFpEF) is increasingly prevalent with a high socioeconomic burden. Pharmacological heart rate lowering was recommended to improve ventricular filling in HFpEF. This article discusses the misperceptions that have resulted in an overprescription of beta-blockers, which in all likelihood have untoward effects on patients with HFpEF, even if they have atrial fibrillation or coronary artery disease as a comorbidity. Directly contradicting the lower heart rate paradigm, faster heart rates provide haemodynamic and structural benefits, amongst which lower cardiac filling pressures and improved ventricular capacitance may be most important. Safe delivery of this therapeutic approach is feasible with atrial and ventricular conduction system pacing that aims to emulate or enhance cardiac excitation to maximize the haemodynamic benefits of accelerated pacing. This conceptual framework was first tested in the myPACE randomized controlled trial of patients with pre-existing pacemakers and preclinical or overt HFpEF. This article provides the background and path towards this treatment approach.

Mortality, Outcomes, Costs, and Use of Medicines Following a First Heart Failure Hospitalization: EVOLUTION HF

BACKGROUND

There are few contemporary data on outcomes, costs, and treatment following a hospitalization for heart failure (hHF) in epidemiologically representative cohorts.

OBJECTIVES

This study sought to describe rehospitalizations, hospitalization costs, use of guideline-directed medical therapy (GDMT) (renin-angiotensin system inhibitors, sacubitril/valsartan, beta-blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter-2 inhibitors), and mortality after hHF.

METHODS

EVOLUTION HF (Utilization of Dapagliflozin and Other Guideline Directed Medical Therapies in Heart Failure Patients: A Multinational Observational Study Based on Secondary Data) is an observational, longitudinal cohort study using data from electronic health records or claims data sources in Japan, Sweden, the United Kingdom, and the United States. Adults with a first hHF discharge between 2018 and 2022 were included. The 1-year event rates per 100 patient-years (ERs) for death and rehospitalizations (with a primary diagnosis of heart failure (HF), chronic kidney disease [CKD], myocardial infarction, stroke, or peripheral artery disease) were calculated. Hospital health care costs were cumulatively summarized. Cumulative GDMT use was assessed using Kaplan-Meier estimates.

RESULTS

Of 263,525 patients, 28% died within the first year post-hHF (ER: 28.4 [95% CI: 27.0-29.9]). Rehospitalizations were mainly driven by HF (ER: 13.6 [95% CI: 9.8-17.4]) and CKD (ER: 4.5 [95% CI: 3.6-5.3]), whereas the ERs for myocardial infarction, stroke, and peripheral artery disease were lower. Health care costs were predominantly driven by HF and CKD. Between 2020 and 2022, use of renin-angiotensin system inhibitors, sacubitril/valsartan, beta-blockers, and mineralocorticoid receptor antagonists changed little, whereas uptake of sodium-glucose cotransporter-2 inhibitors increased 2- to 7-fold.

CONCLUSIONS

Incident post-hHF rehospitalization risks and costs were high, and GDMT use changed little in the year following discharge, highlighting the need to consider earlier and greater implementation of GDMT to manage risks and reduce costs.

Targeting histone deacetylases for heart diseases

Histone deacetylases (HDACs) are responsible for the deacetylation of lysine residues in histone or non-histone substrates, leading to the regulation of many biological functions, such as gene transcription, translation and remodeling chromatin. Targeting HDACs for drug development is a promising way for human diseases, including cancers and heart diseases. In particular, numerous HDAC inhibitors have revealed potential clinical value for the treatment of cardiac diseases in recent years. In this review, we systematically summarize the therapeutic roles of HDAC inhibitors with different chemotypes on heart diseases. Additionally, we discuss the opportunities and challenges in developing HDAC inhibitors for the treatment of cardiac diseases.

Hypertensive Heart Failure

Despite overwhelming epidemiological evidence, the contribution of hypertension (HTN) to heart failure (HF) development has been undermined in current clinical practice. This is because approximately half of HF patients have been labeled as suffering from HF with preserved left ventricular (LV) ejection fraction (EF) (HFpEF), with HTN, obesity, and diabetes mellitus (DM) being considered virtually equally responsible for its development. However, this suggestion is obviously inaccurate, since HTN is by far the most frequent and devastating morbidity present in HFpEF. Further, HF development in obesity or DM is rare in the absence of HTN or coronary artery disease (CAD), whereas HTN often causes HF per se. Finally, unlike HTN, for most major comorbidities present in HFpEF, including anemia, chronic kidney disease, pulmonary disease, DM, atrial fibrillation, sleep apnea, and depression, it is unknown whether they precede HF or result from it. The purpose of this paper is to provide a contemporary overview on hypertensive HF, with a special emphasis on its inflammatory nature and association with autonomic nervous system (ANS) imbalance, since both are of pathophysiologic and therapeutic interest.

Beta-Blocker Use and Heart Failure Outcomes in Mildly Reduced and Preserved Ejection Fraction

BACKGROUND

Although studies consistently show that beta-blockers reduce morbidity and mortality in patients with reduced ejection fraction (EF), data are inconsistent in patients with heart failure with mildly reduced ejection fraction (HFmrEF) and suggest potential negative effects in heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

The purpose of this study was to examine the association of beta-blockers with heart failure (HF) hospitalization and death in patients with HF and EF ≥40% METHODS: Beta-blocker use was assessed at first encounter in outpatients ≥65 years of age with HFmrEF and HFpEF in the U.S. PINNACLE Registry (2013-2017). The associations of beta-blockers with HF hospitalization, death, and the composite of HF hospitalization/death were assessed using propensity-score adjusted multivariable Cox regression models, including interactions of EF × beta-blocker use.

RESULTS

Among 435,897 patients with HF and EF ≥40% (HFmrEF, n = 75,674; HFpEF = 360,223), 289,377 (66.4%) were using a beta-blocker at first encounter; more commonly in patients with HFmrEF vs HFpEF (77.7% vs 64.0%; P < 0.001). There were significant interactions between EF × beta-blocker use for HF hospitalization, death, and composite of HF hospitalization/death (P < 0.001 for all), with higher risk with beta-blocker use as EF increased. Beta-blockers were associated with decreased risk of HF hospitalization and death in patients with HFmrEF but a lack of survival benefit and a higher risk of HF hospitalization in patients with HFpEF, particularly when EF was >60%.

CONCLUSIONS

In a large, real-world, propensity score-adjusted cohort of older outpatients with HF and EF ≥40%, beta-blocker use was associated with a higher risk of HF hospitalization as EF increased, with potential benefit in patients with HFmrEF and potential risk in patients with higher EF (particularly >60%). Further studies are needed to understand the appropriateness of beta-blocker use in patients with HFpEF in the absence of compelling indications.

Association of Nondihydropyridine Calcium Channel Blockers Versus β-Adrenergic Receptor Blockers With Risk of Heart Failure Hospitalization

Heart failure (HF) with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are interrelated and often coexisting conditions in older adults. Although equally recommended, nondihydropyridine calcium channel blockers (non-DHP CCBs), such as diltiazem and verapamil, are less often used than β blockers. Because recent studies suggested that β-blocker use in both HFpEF and AF may increase the risk for HF, we tested whether non-DHP CCBs were associated with lower HF hospitalization risk than β blockers. We examined fee-for-service Medicare beneficiaries who were aged ≥66 years, had HFpEF or AF, and newly initiated a β blocker (n = 83,458) or non-DHP CCB (n = 18,924) from 2014 to 2018. The outcomes of HF hospitalization and all-cause mortality were analyzed using multivariable-adjusted Cox regression in the full cohort and, separately, in the subset without a recent hospital or skilled nursing discharge. Follow-up was analyzed using 2 frameworks: intention-to-treat and censored-at-drug-switch-or-discontinuation. There was a modestly protective association of non-DHP CCBs for the risk of HF hospitalization. Before drug switch or discontinuation, the use of diltiazem or verapamil was associated with decreased risk of HF hospitalization in the full cohort (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.81 to 1.00, p = 0.05) and in the subgroup (HR 0.70, 95% CI 0.56 to 0.89, p = 0.003). However, the association with all-cause mortality tended to favor β blockers, including in the intention-to-treat analysis (HR 1.21, 95% CI 1.17 to 1.25, p <0.001). In conclusion, compared with β blockers, the initiation of diltiazem or verapamil in patients with HFpEF or AF may be associated with fewer HF hospitalization events but also with more all-cause deaths.

Lower heart rates and beta-blockers are associated with new-onset atrial fibrillation

Background

Lower heart rates (HRs) prolong diastole, which increases filling pressures and wall stress. As a result, lower HRs may be associated with higher brain natriuretic peptide (BNP) levels and incident atrial fibrillation (AF). Beta-blockers may increase the risk for AF due to suppression of resting HRs.

Objective

Examine the relationships of HR, BNP, beta-blockers and new-onset AF in the REVEAL-AF and SPRINT cohort of subjects at risk for developing AF.

Methods

In REVEAL-AF, 383 subjects without a history of AF and a mean CHA₂DS₂VASC score of 4.4 ± 1.3 received an insertable cardiac monitor and were followed up to 30 months. In SPRINT, 7595 patients without prior history of AF and a mean CHA₂DS₂VASC score of 2.3 ± 1.2 were followed up to 60 months.

Results

The median daytime HR in the REVEAL-AF cohort was 75bpm [IQR 68-83]. Subjects with below-median HRs had 2.4-fold higher BNP levels compared to subjects with above-median HRs (median BNP [IQR]: 62 pg/dl [37-112] vs. 26 pg/dl [13-53], p < 0.001). HRs <75bpm were associated with a higher incidence of AF: 37% vs. 27%, p < 0.05. This was validated in the SPRINT cohort after adjusting for AF risk factors. Both a HR < 75bpm and beta-blocker use were associated with a higher rate of AF: 1.9 vs 0.7% (p < 0.001) and 2.5% vs. 0.6% (p < 0.001), respectively. The hazard ratio for patients on beta-blockers to develop AF was 3.72 [CI 2.32, 5.96], p < 0.001.

Conclusions

Lower HRs are associated with higher BNP levels and incident AF, mimicking the hemodynamic effects of diastolic dysfunction. Suppression of resting HR by beta-blockers could explain their association with incident AF.

Physician Perspectives on the Use of Beta Blockers in Heart Failure With Preserved Ejection Fraction

β-blockers are commonly used in heart failure with preserved ejection fraction (HFpEF), even in the absence of a compelling indication and despite the potential to cause harm. Identifying reasons for β-blocker prescription in HFpEF could permit the development of strategies to reduce unnecessary use and potentially improve medication prescribing patterns in this vulnerable population. We administered an online survey regarding β-blocker prescribing behavior to physicians trained in internal medicine or geriatrics (noncardiology physicians) and to cardiologists at 2 large academic medical centers. The survey assessed the reasons for β-blocker initiation, agreement regarding initiation and/or continuation of β-blockers by another clinician, and deprescribing behavior. The response rate was 28.2% (n = 231). Among respondents, 68.2% reported initiating β-blockers in patients with HFpEF. The most common reason for initiating a β-blocker was for treatment of an atrial arrhythmia. Notably, 23.7% of physicians reported initiating a β-blocker without an evidence-based indication. When a β-blocker was considered not necessary, 40.1% of physicians reported they were rarely or never willing to deprescribe. The most common reason for not deprescribing a β-blocker when the physician felt that a β-blocker was unnecessary was the concern about interfering with another physicians' treatment plan (76.6%). In conclusion, a significant proportion of noncardiology physicians and cardiologists report prescribing β-blockers to patients with HFpEF, even when evidence-based indications are absent, and rarely deprescribe β-blockers in these scenarios.

Investigating the effects of beta-blockers on circadian heart rhythm using heart rate variability in ischemic heart disease with preserved ejection fraction

Heart failure is characterized by sympathetic activation and parasympathetic withdrawal leading to an abnormal autonomic modulation. Beta-blockers (BB) inhibit overstimulation of the sympathetic system and are indicated in heart failure patients with reduced ejection fraction. However, the effect of beta-blocker therapy on heart failure with preserved ejection fraction (HFpEF) is unclear. ECGs of 73 patients with HFpEF > 55% were recruited. There were 56 patients in the BB group and 17 patients in the without BB (NBB) group. The HRV analysis was performed for the 24-h period using a window size of 1,4 and 8-h. HRV measures between day and night for both the groups were also compared. Percentage change in the BB group relative to the NBB group was used as a measure of difference. RMSSD (13.27%), pNN50 (2.44%), HF power (44.25%) and LF power (13.53%) showed an increase in the BB group relative to the NBB group during the day and were statistically significant between the two groups for periods associated with high cardiac risk during the morning hours. LF:HF ratio showed a decrease of 3.59% during the day. The relative increase in vagal modulated RMSSD, pNN50 and HF power with a decrease in LF:HF ratio show an improvement in the parasympathetic tone and an overall decreased risk of a cardiac event especially during the morning hours that is characterized by a sympathetic surge.

Effect of Personalized Accelerated Pacing on Quality of Life, Physical Activity, and Atrial Fibrillation in Patients With Preclinical and Overt Heart Failure With Preserved Ejection Fraction: The myPACE Randomized Clinical Trial

Importance

Patients with heart failure with preserved ejection fraction (HFpEF) with a pacemaker may benefit from a higher, more physiologic backup heart rate than the nominal 60 beats per minute (bpm) setting.

Objective

To assess the effects of a moderately accelerated personalized backup heart rate compared with 60 bpm (usual care) in patients with preexisting pacemaker systems that limit pacemaker-mediated dyssynchrony.

Design, Setting, and Participants

This blinded randomized clinical trial enrolled patients with stage B and C HFpEF from the University of Vermont Medical Center pacemaker clinic between June 2019 and November 2020. Analysis was modified intention to treat.

Interventions

Participants were randomly assigned to personalized accelerated pacing or usual care and were followed up for 1 year. The personalized accelerated pacing heart rate was calculated using a resting heart rate algorithm based on height and modified by ejection fraction.

Main Outcomes and Measures

The primary outcome was the serial change in Minnesota Living with Heart Failure Questionnaire (MLHFQ) score. Secondary end points were changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, pacemaker-detected physical activity, atrial fibrillation from baseline, and adverse clinical events.

Results

Overall, 107 participants were randomly assigned to the personalized accelerated pacing (n = 50) or usual care (n = 57) groups. The median (IQR) age was 75 (69-81) years, and 48 (48%) were female. Over 1-year follow-up, the median (IQR) pacemaker-detected heart rate was 75 (75-80) bpm in the personalized accelerated pacing arm and 65 (63-68) bpm in usual care. MLHFQ scores improved in the personalized accelerated pacing group (median [IQR] baseline MLHFQ score, 26 [8-45]; at 1 month, 15 [2-25]; at 1 year, 9 [4-21]; P < .001) and worsened with usual care (median [IQR] baseline MLHFQ score, 19 [6-42]; at 1 month, 23 [5-39]; at 1 year, 27 [7-52]; P = .03). In addition, personalized accelerated pacing led to improved changes in NT-proBNP levels (mean [SD] decrease of 109 [498] pg/dL vs increase of 128 [537] pg/dL with usual care; P = .02), activity levels (mean [SD], +47 [67] minutes per day vs -22 [35] minutes per day with usual care; P < .001), and device-detected atrial fibrillation (27% relative risk reduction compared with usual care; P = .04) over 1-year of follow-up. Adverse clinical events occurred in 4 patients in the personalized accelerated pacing group and 11 patients in usual care.

Conclusions and Relevance

In this study, among patients with HFpEF and pacemakers, treatment with a moderately accelerated, personalized pacing rate was safe and improved quality of life, NT-proBNP levels, physical activity, and atrial fibrillation compared with the usual 60 bpm setting.

Trial Registration

ClinicalTrials.gov Identifier: NCT04721314.

Rapid Selective Detection and Quantification of β-Blockers Used in Doping Based on Molecularly Imprinted Nanoparticles (NanoMIPs)

Human performance enhancing drugs (PEDs), frequently used in sport competitions, are strictly prohibited by the World Anti-Doping Agency (WADA). Biological samples collected from athletes and regular patients are continuously tested regarding the identification and/or quantification of the banned substances. Current work is focused on the application of a new analytical method, molecularly imprinted nanoparticles (nanoMIPs), to detect and determine concentrations of certain prohibited drugs, such as β-blockers, in water and human urine samples. These medications are used in the treatment of cardiovascular conditions, negative effects of adrenaline (helping to relief stress), and hypertension (slowing down the pulse and softening the arteries). They can also significantly increase muscle relaxation and improve heart efficiency. The new method of the detection and quantification of β-blockers is based on synthesis, characterization, and implementation of nanoMIPs (so-called plastic antibodies). It offers numerous advantages over the traditional methods, including high binding capacity, affinity, and selectivity for target molecules. Additionally, the whole process is less complicated, cheaper, and better controlled. The size and shape of the nanoMIPs is evaluated by dynamic light scattering (DLS) and transmission electron microscope (TEM). The affinity and selectivity of the nanoparticles are investigated by competitive pseudo enzyme-linked immunosorbent assay (pseudo-ELISA) similar to common immunoassays employing natural antibodies. To provide reliable results towards either doping detection or therapeutic monitoring using the minimal invasive method, the qualitative and quantitative analysis of these drugs is performed in water and human urine samples. It is demonstrated that the assay can detect β-blockers in water within the linear range 1 nmol·L^-1-1 mmol·L^-1 for atenolol with the detection limit 50.6 ng mL^-1, and the linear range 1 mmol·L^-1-10 mmol·L^-1 for labetalol with the detection limit of 90.5 ng·mL^-1. In human urine samples, the linear range is recorded in the concentration range 0.1 mmol·L^-1-10 nmol·L^-1 for atenolol and 1 mmol·L^-1-10 nmol·L^-1 for labetalol with a detection limit of 61.0 ng·mL-1 for atenolol and 99.4 ng·mL^-1 for labetalol.

N-of-1 trials to facilitate evidence-based deprescribing: Rationale and case study

Deprescribing has emerged as an important aspect of patient-centred medication management but is vastly underutilized in clinical practice. The current narrative review will describe an innovative patient-centred approach to deprescribing-N-of-1 trials. N-of-1 trials involve multiple-period crossover design experiments conducted within individual patients. They enable patients to compare the effects of two or more treatments or, in the case of deprescribing N-of-1 trials, continuation with a current treatment versus no treatment or placebo. N-of-1 trials are distinct from traditional between-patient studies such as parallel-group or crossover designs which provide an average effect across a group of patients and obscure differences between individuals. By generating data on the effect of an intervention for the individual rather than the population, N-of-1 trials can promote therapeutic precision. N-of-1 trials are a particularly appealing strategy to inform deprescribing because they can generate individual-level evidence for deprescribing when evidence is uncertain, and can thus allay patient and physician concerns about discontinuing medications. To illustrate the use of deprescribing N-of-1 trials, we share a case example of an ongoing series of N-of-1 trials that compare maintenance versus deprescribing of beta-blockers in patients with heart failure with preserved ejection fraction. By providing quantifiable data on patient-reported outcomes, promoting personalized pharmacotherapy, and facilitating shared decision making, N-of-1 trials represent a potentially transformative strategy to address polypharmacy.

Effect of Ivabradine on Left Ventricular Diastolic Function of Patients With Preserved Ejection Fraction ― Results of the IVA-PEF Study ―

Background: The association between heart rate (HR) reductions caused by ivabradine and left ventricular (LV) diastolic function in heart failure with preserved ejection fraction (HFpEF) remains uncertain because of off-label use. Thus, the present study investigated the effect of HR reductions by ivabradine on LV diastolic function in HFpEF patients.

Methods and Results: This study enrolled 16 HFpEF patients with HR ≥75 beats/min. After 3 months administration of ivabradine, no significant changes were observed in mitral inflow E and mitral e’ annular velocities, B-type natriuretic peptide, or left atrial volume index, but there were significant improvements in global longitudinal strain.

Conclusions: Ivabradine did not improve LV diastolic function for HFpEF patients with HR ≥75 beats/min. Because this may be due to some study limitations, further studies should be conducted.

Peak O2 -pulse predicts exercise training-induced changes in peak V̇O2 in heart failure with preserved ejection fraction

AIMS

Exercise training (ET) has been consistently shown to increase peak oxygen consumption (V̇O₂ ) in patients with heart failure with preserved ejection fraction (HFpEF); however, inter-individual responses vary significantly. Because it is unlikely that ET-induced improvements in peak V̇O₂ are significantly mediated by an increase in peak heart rate (HR), we aimed to investigate whether baseline peak O₂ -pulse (V̇O₂  × HR^-1 , reflecting the product of stroke volume and arteriovenous oxygen difference), not baseline peak V̇O₂ , is inversely associated with the change in peak V̇O₂ (adjusted by body weight) following ET versus guideline control (CON) in patients with HFpEF.

METHODS AND RESULTS

This was a secondary analysis of the OptimEx-Clin (Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure, NCT02078947) trial, including all 158 patients with complete baseline and 3 month cardiopulmonary exercise testing measurements (106 ET, 52 CON). Change in peak V̇O₂ (%) was analysed as a function of baseline peak V̇O₂ and its determinants (absolute peak V̇O₂ , peak O₂ -pulse, peak HR, weight, haemoglobin) using robust linear regression analyses. Mediating effects on change in peak V̇O₂ through changes in peak O₂ -pulse, peak HR and weight were analysed by a causal mediation analysis with multiple correlated mediators. Change in submaximal exercise tolerance (V̇O₂ at the ventilatory threshold, VT1) was analysed as a secondary endpoint. Among 158 patients with HFpEF (66% female; mean age, 70 ± 8 years), changes in peak O₂ -pulse explained approximately 72% of the difference in changes in peak V̇O₂ between ET and CON [10.0% (95% CI, 4.1 to 15.9), P = 0.001]. There was a significant interaction between the groups for the influence of baseline peak O₂ -pulse on change in peak V̇O₂ (interaction P = 0.04). In the ET group, every 1 mL/beat higher baseline peak O₂ -pulse was associated with a decreased mean change in peak V̇O₂ of -1.45% (95% CI, -2.30 to -0.60, P = 0.001) compared with a mean change of -0.08% (95% CI, -1.11 to 0.96, P = 0.88) following CON. None of the other factors showed significant interactions with study groups for the change in peak V̇O₂ (P > 0.05). Change in V̇O₂ at VT1 was not associated with any of the investigated factors (P > 0.05).

CONCLUSIONS

In patients with HFpEF, the easily measurable peak O₂ -pulse seems to be a good indicator of the potential for improving peak V̇O₂ through exercise training. While changes in submaximal exercise tolerance were independent of baseline peak O₂ -pulse, patients with high O₂ -pulse may need to use additional therapies to significantly increase peak V̇O₂ .

Diastolic Filling Time, Chronotropic Response, and Exercise Capacity in Heart Failure and Preserved Ejection Fraction With Sinus Rhythm

Background

Exercise‐induced high heart rate may impair exercise tolerance by reducing diastolic filling time and ventricular filling in heart failure with preserved ejection fraction (HFpEF). Given the importance of chronotropic response, we hypothesized that reduction in diastolic filling time because of exercise‐induced increased heart rate would not impair cardiac output reserve and exercise capacity. We sought to determine the association between heart rate, diastolic filling time, hemodynamics, and exercise capacity in HFpEF.

Methods and Results

Patients with HFpEF (n=66) and controls without HF (n=107) underwent bicycle exercise echocardiography with simultaneous expired gas analysis to measure oxygen consumption. Diastolic filling time was assessed by the overlap time between mitral E‐ and A‐waves (longer overlap time indicates shorter diastolic filling duration). Overlap time increased (ie, diastolic filling time shortened) in HFpEF and controls as heart rate increased with exercise, and the relationship was similar between the groups. Greater heart rate response correlated with higher cardiac output (r=0.51, P<0.0001) and oxygen consumption (r=0.50, P<0.0001) during peak exercise. Shorter diastolic filling time, as assessed by longer overlap time, was correlated with higher cardiac output (r=0.47, P<0.0001) and peak oxygen consumption (r=0.38, P=0.007), not with E/e′ or right ventricular‐pulmonary artery uncoupling. Longer overlap time was associated with mitral A velocity (r=0.53, P<0.0001) and left atrial booster pump strain (r=0.42, P<0.0001).

Conclusions

Shortening of diastolic filling interval in tandem with increased heart rate during exercise does not limit cardiac output reserve or exercise capacity in HFpEF.

Beta-blockers are associated with increased B-type natriuretic peptide levels differently in men and women in heart failure with preserved ejection fraction

Beta-blocker (BB) use is a mainstay for treatment of heart failure (HF) with reduced ejection fraction (HFrEF), whereas its efficacy for heart failure with preserved ejection fraction (HFpEF) remains controversial. Women outnumber men in HFpEF, whereas men outnumber women in HFrEF. Plasma B-type natriuretic peptide (BNP) is established as a biomarker for HF. We examined whether BB use is associated with plasma BNP levels differently in men and women with HFpEF. The study subjects comprised 721 patients with HFpEF (LVEF≥50%) (184 men, mean age 78.2±9.2 and 537 women, mean age 83.1±8.8), 179 on BB (66 men and 113 women) and 542 (118 men and 424 women) not, 583 in sinus rhythm (SR) and 138 in atrial fibrillation (AF). Multivariable logistic regression test was utilized. Plasma BNP levels were higher (P=0.0005), systolic blood pressure and LVEF lower (P=0.0003, and P=0.0059, respectively) on BBs than on no-BBs in women, whereas in men plasma BNP levels, systolic blood pressure, and LVEF were not altered significantly (P=0.0849, P=0.9129, and P=0.4718, respectively) on BBs compared to no-BBs in patients with SR. Multivariable logistic regression analysis revealed that BB use and women were a positive and a negative predictor for high BNP levels (P=0.003 and P=0.032, respectively) in SR but not in AF. BB use was associated with high plasma BNP levels and lower LVEF in women but not in men with HFpEF and SR, suggesting that the pathogenesis and of HFpEF may differ in men and women in SR.

Beta-Blocker Use in Hypertension and Heart Failure (A Secondary Analysis of the Systolic Blood Pressure Intervention Trial)

Given the concern that beta-blocker use may be associated with an increased risk for heart failure (HF) in populations with normal left ventricular systolic function, we evaluated the association between beta-blocker use and incident HF events, as well as loop diuretic initiation in the Systolic Blood Pressure Intervention Trial (SPRINT). SPRINT demonstrated that a blood pressure target of <120 mm Hg reduced cardiovascular outcomes compared with <140 mm Hg in adults with at least one cardiovascular risk factor and without HF. The lower rate of the composite primary outcome in the 120 mm Hg group was primarily driven by a reduction in HF events. Subjects on a beta blocker for the entire trial duration were compared with subjects who never received a beta blocker after 1:1 propensity score matching. A competing risk survival analysis by beta-blocker status was performed to estimate the effect of the drug on incident HF and was then repeated for a secondary end point of cardiovascular disease death. Among the 3,284 propensity score-matched subjects, beta-blocker exposure was associated with an increased HF risk (hazard ratio 5.86; 95% confidence interval 2.73 to 13.04; p <0.001). A sensitivity analysis of propensity score-matched cohorts with a history of coronary artery disease or atrial fibrillation revealed the same association (hazard ratio 3.49; 95% confidence interval 1.15 to 10.06; p = 0.028). In conclusion, beta-blocker exposure in this secondary analysis was associated with increased incident HF in subjects with hypertension without HF at baseline.

Personalized pacing for diastolic dysfunction and heart failure with preserved ejection fraction: Design and rationale for the myPACE randomized controlled trial

Background

Patients with pacemakers and heart failure with preserved ejection fraction (HFpEF) or isolated diastolic dysfunction (DD) may benefit from a higher backup heart rate (HR) setting compared with the standard setting of 60 bpm.

Objective

The purpose of this study was to assess the effects of a personalized backup HR setting (myPACE group) compared with 60 bpm (control group).

Methods

In this prospective, blinded, randomized controlled study, pacemaker patients with DD or HFpEF and atrial pacing with intrinsic ventricular conduction or conduction system or biventricular pacing are randomized to the myPACE group or control group for 1 year. The primary outcome is the change in Minnesota Living with Heart Failure Questionnaire (MLHFQ) scores. Secondary endpoints include changes in N-terminal pro–brain natriuretic peptide levels, physical and emotional MLHFQ subscores, and pacemaker-detected atrial arrhythmia burden, patient activity levels, and thoracic impedance; hospitalization for heart failure, atrial fibrillation, cerebrovascular accident, or myocardial infarction; and loop diuretic or antiarrhythmic medication initiation or up-titration. A sample size of 118 subjects is expected to allow detection of a 5-point change in MLHFQ score in an intention-to-treat analysis and allow initial assessment of clinical outcomes and subgroup analyses.

Results

Enrollment began in July 2019. As of November 2020, 107 subjects have been enrolled. It is projected that the 1-year follow-up will be completed by December 2021.

Conclusion

Atrial pacing with intrinsic ventricular conduction or advanced ventricular pacing at a higher, personalized backup HR may be a therapeutic target for patients with isolated DD or HFpEF. The myPACE trial is designed to test this hypothesis.

Effect of β-Blocker Withdrawal on Functional Capacity in Heart Failure and Preserved Ejection Fraction

BACKGROUND

Chronotropic incompetence has shown to be associated with a decrease in exercise capacity in heart failure with preserved ejection fraction (HFpEF), yet β-blockers are commonly used in HFpEF despite the lack of robust evidence.

OBJECTIVES

This study aimed to evaluate the effect of β-blocker withdrawal on peak oxygen consumption (peak Vo₂) in patients with HFpEF and chronotropic incompetence.

METHODS

This is a multicenter, randomized, investigator-blinded, crossover clinical trial consisting of 2 treatment periods of 2 weeks separated by a washout period of 2 weeks. Patients with stable HFpEF, New York Heart Association functional classes II and III, previous treatment with β-blockers, and chronotropic incompetence were first randomized to withdrawing from (arm A: n = 26) versus continuing (arm B: n = 26) β-blocker treatment and were then crossed over to receive the opposite intervention. Changes in peak Vo₂ and percentage of predicted peak Vo₂ (peak Vo₂%) measured at the end of the trial were the primary outcome measures. To account for the paired-data nature of this crossover trial, linear mixed regression analysis was used.

RESULTS

The mean age was 72.6 ± 13.1 years, and most of the patients were women (59.6%) in New York Heart Association functional class II (66.7%). The mean peakVo₂ and peak Vo₂% were 12.4 ± 2.9 mL/kg/min, and 72.4 ± 17.8%, respectively. No significant baseline differences were found across treatment arms. Peak Vo₂ and peak Vo₂% increased significantly after β-blocker withdrawal (14.3 vs 12.2 mL/kg/min [Δ +2.1 mL/kg/min]; P < 0.001 and 81.1 vs 69.4% [Δ +11.7%]; P < 0.001, respectively).

CONCLUSIONS

β-blocker withdrawal improved maximal functional capacity in patients with HFpEF and chronotropic incompetence. β-blocker use in HFpEF deserves profound re-evaluation. (β-blockers Withdrawal in Patients With HFpEF and Chronotropic Incompetence: Effect on Functional Capacity [PRESERVE-HR]; NCT03871803; 2017-005077-39).

Heart Failure with Perserved Ejection Fraction Current Diagnostic and Therapeutic Approaches

Heart failure with preserved ejection fraction (HFpEF) is a syndrome associated with high morbidity and mortality rates. Little progress has been in the treatment of this condition since its introduction some 30 years ago. It's accepted that HFpEF is heterogeneous in many ways, ethologically and phenotypically. The underlying mechanisms of the syndrome are not clear. Recently, it has been shown that the diagnostic criteria for HFpEF lacks sensitivity and specificity. Novel treatment approaches, which were developed based on current HFpEF pathophysiological concepts, did not show either clinical or prognostic benefit for patients. Therefore, there is an urgent need to revise current diagnostic approaches and to further investigate the underlying mechanisms. Recently, two novel diagnostic score systems were proposed: H2PEF and HFA-PEFF. Recently, a number of phase II and III randomized control trials have been completed. Here, the authors discuss the potential novel diagnostic approaches to HFpEF and treatment perspectives.

Hypertension and heart failure with preserved ejection fraction: position paper by the European Society of Hypertension

Hypertension constitutes a major risk factor for heart failure with preserved ejection fraction (HFpEF). HFpEF is a prevalent clinical syndrome with increased cardiovascular morbidity and mortality. Specific guideline-directed medical therapy (GDMT) for HFpEF is not established due to lack of positive outcome data from randomized controlled trials (RCTs) and limitations of available studies. Although available evidence is limited, control of blood pressure (BP) is widely regarded as central to the prevention and clinical care in HFpEF. Thus, in current guidelines including the 2018 European Society of Cardiology (ESC) and European Society of Hypertension (ESH) Guidelines, blockade of the renin-angiotensin system (RAS) with either angiotensin-converting enzyme inhibitors or angiotensin receptor blockers provides the backbone of BP-lowering therapy in hypertensive patients. Although superiority of RAS blockers has not been clearly shown in dedicated RCTs designed for HFpEF, we propose that this core drug treatment strategy is also applicable for hypertensive patients with HFpEF with the addition of some modifications. The latter apply to the use of spironolactone apart from the treatment of resistant hypertension and the use of the angiotensin receptor neprilysin inhibitor. In addition, novel agents such as sodium-glucose co-transporter-2 inhibitors, currently already indicated for high-risk patients with diabetes to reduce heart failure hospitalizations, and finerenone represent promising therapies and results from ongoing RCTs are eagerly awaited. The development of an effective and practical classification of HFpEF phenotypes and GDMT through dedicated high-quality RCTs are major unmet needs in hypertension research and calls for action.

Association between up-titration of medical therapy and total hospitalizations and mortality in patients with recent worsening heart failure across the ejection fraction spectrum

BACKGROUND

The role of neurohormonal inhibition in chronic heart failure (HF) is well established. There are limited data on the effect of up-titration of renin-angiotensin inhibitors (RASi) and beta-blockers (BBs) on clinical outcomes of patients with worsening HF across the left ventricular ejection fraction (LVEF) spectrum.

METHODS AND RESULTS

We analysed data from 2345 patients from BIOSTAT-CHF (80.9% LVEF <40%), who completed a 3-month up-titration period after recent worsening of HF. Patients were classified by achieved dose (% of recommended): ≥100%, 50-99%, 1-49%, and none. Recurrent event analysis using joint and shared frailty models was used to examine the association between RASi/BB dose and all-cause and HF hospitalizations. In the 21 months following up-titration, 512 patients died and 879 (37.5%) had ≥1 hospitalization. RASi up-titration was associated, incrementally, with reduced risk of all-cause hospitalization at all achieved dose levels compared to no treatment [hazard ratio (95% confidence interval): ≥100%: 0.60 (0.49-0.74), P < 0.001; 50-99%: 0.56 (0.46-0.68), P < 0.001; 1-49%: 0.71 (0.59-0.86), P < 0.001]. This association was consistent up to an LVEF of 49% (P < 0.001), and when considering only HF hospitalizations. Up-titration of BBs was associated with fewer all-cause hospitalizations only when LVEF was <40% (overall P < 0.001), but with more HF hospitalizations when LVEF was ≥50%. Up-titration of both RASi/BBs was associated with lower mortality in LVEF up to 49%.

CONCLUSION

After recent worsening of HF, up-titration of RASi and BBs was associated with a better prognosis in patients with LVEF ≤49%. Up-titration of BBs was associated with a greater risk of HF hospitalization when LVEF was ≥50%.

Heart failure with mid-range ejection fraction and the effect of β-blockers after acute myocardial infarction

There is currently an ongoing debate about the 'grey area' of heart failure with mid-range ejection fraction (HFmrEF). We evaluated characteristics, prognosis, and the effect of β-blockers on clinical outcomes in patients with HFmrEF after acute myocardial infarction (AMI). We included a total of 10,785 patients and divided them into three groups: EF 40-49% (HFmrEF; n = 2717; reference); EF < 40% (reduced EF [HFrEF]; n = 1194); and EF ≥ 50% (preserved EF [HFpEF]; n = 6874). The primary outcome was 2-year all-cause mortality. HFmrEF was intermediate between HFrEF and HFpEF for baseline characteristics. The risk of all-cause mortality was lower for HFmrEF patients compared to HFrEF patients (adjusted hazard ratio [HR] 0.710; 95% confidence interval [CI] 0.544-0.927; P = 0.012). However, HFmrEF patients tended to be at higher risk for 2-year all-cause mortality than HFpEF patients (adjusted HR 1.235; 95% CI 0.989-1.511; P = 0.090). β-blockers were associated with reductions in all-cause mortality for the entire cohort (adjusted HR 0.760; 95% CI 0.592-0.975; P = 0.031). β-blockers were effective in patients with HFrEF (adjusted HR 0.667; 95% CI 0.471-0.944; P = 0.022), tended to be effective in patients with HFmrEF (adjusted HR 0.665; 95% CI 0.426-1.038; P = 0.072), but not effective in patients with HFpEF (adjusted HR 0.852; 95% CI 0.548-1.326; P = 0.478; interaction P = 0.026). In conclusion, clinical profiles and prognosis of patients with post-AMI HFmrEF are largely intermediate between HFrEF and HFpEF. β-blockers reduced or tended to reduce 2-year all-cause mortality in patients with HFrEF or HFmrEF, respectively, but not those with HFpEF after AMI.

Attitudes toward deprescribing among adults with heart failure with preserved ejection fraction

BACKGROUND/OBJECTIVES

Attitudes toward deprescribing could vary among subpopulations. We sought to understand patient attitudes toward deprescribing among patients with heart failure with preserved ejection fraction (HFpEF).

DESIGN

Retrospective cohort study.

SETTING

Academic medical center in New York City.

PARTICIPANTS

Consecutive patients with HFpEF seen in July 2018-December 2019 at a program dedicated to providing care to older adults with HFpEF.

MEASUREMENTS

We assessed the prevalence of vulnerabilities outlined in the domain management approach for caring for patients with heart failure and examined data on patient attitudes toward having their medicines deprescribed via the revised Patient Attitudes Toward Deprescribing (rPATD).

RESULTS

Among 134 patients with HFpEF, median age was 75 (interquartile range 69-82), 60.4% were women, and 35.8% were nonwhite. Almost all patients had polypharmacy (94.0%) and 56.0% had hyperpolypharmacy; multimorbidity (80.6%) and frailty (78.7%) were also common. Overall, 90.3% reported that they would be willing to have one or more of their medicines deprescribed if told it was possible by their doctors; and 26.9% reported that they would like to try stopping one of their medicines to see how they feel without it. Notably, 91.8% of patients reported that they would like to be involved in decisions about their medicines. In bivariate logistic regression, nonwhite participants were less likely to want to try stopping one of their medicines to see how they feel without it (odds ratio 0.25, 95% confidence interval [0.09-0.62], p = 0.005).

CONCLUSIONS

Patients with HFpEF contend with many vulnerabilities that could prompt consideration for deprescribing. Most patients with HFpEF were amenable to deprescribing. Race may be an important factor that impacts patient attitudes toward deprescribing.

Association Between β-Blockers and Outcomes in Heart Failure With Preserved Ejection Fraction: Current Insights From the SwedeHF Registry

BACKGROUND

β-Blockers have an uncertain effect in heart failure with a preserved ejection fraction of 50% or higher (heart failure with preserved ejection fraction [HFpEF]).

METHODS AND RESULTS

We included patients with HFpEF from the Swedish Heart Failure Registry (SwedeHF) enrolled from 2011 through 2018. In a 2:1 propensity-score matched analysis (β-blocker use vs nonuse), we assessed the primary outcome first HF hospitalization, the coprimary outcome cardiovascular (CV) death, and the secondary outcomes of all-cause hospitalization and all-cause death. We performed intention-to-treat and a per-protocol consistency analyses. There were a total of 14,434 patients (median age 79 years, IQR 71-85 years, 51% women); 80% were treated with a β-blocker at baseline. Treated patients were younger and had higher rates of atrial fibrillation and coronary artery disease, and higher N-terminal pro-B-type natriuretic peptide levels. In the 4412:2206 patient matched cohort, at 5 years, 42% (95% CI 40%-44%) vs 44% (95% CI 41%-47%) had a HF admission and 38% (IQR 36%-40%) vs 40% (IQR 36%-42%) died from CV causes. In the intention-to-treat analysis, β-blocker use was not associated with HF admissions (hazard ratio 0.95 [95% CI 0.87-1.05, P = .31]) or CV death (hazard ratio 0.94 [95% CI 0.85-1.03, P = .19]). In the subgroup analyses, men seemed to have a more favorable association between β-blockers and outcomes than did women. There were no associations between β-blocker use and secondary outcomes.

CONCLUSIONS

In patients with HFpEF, β-blocker use is common but not associated with changes in HF hospitalization or cardiovascular mortality. In the absence of a strong rational and randomized control trials the case for β-blockers in HFpEF remains inconclusive.

BULLET POINTS

● The effect of β-blockers with heart failure with preserved ejection fraction of 50% or greater is uncertain.● In a propensity score-matched heart failure with preserved ejection fraction analysis in the SwedeHF registry, β-blockers were not associated with a change in risk for heart failure admissions or cardiovascular deaths.

LAY SUMMARY

The optimal treatment for heart failure with a preserved pump function remains unknown. Despite the lack of scientific studies, β-blockers are very commonly used. When matching patients with a similar risk profile in a large heart failure registry, the use of β-blockers for the treatment of heart failure with a preserved pump function was not associated with any changes in heart failure hospital admissions or cardiovascular death.

Carvedilol and exercise combination therapy improves systolic but not diastolic function and reduces plasma osteopontin in Col4a3-/- Alport mice

There are currently no Food and Drug Administration-approved treatments for heart failure with preserved ejection fraction (HFpEF). Here we compared the effects of exercise with and without α/β-adrenergic blockade with carvedilol in Col4a3-/- Alport mice, a model of the phenogroup 3 subclass of HFpEF with underlying renal dysfunction. Alport mice were assigned to the following groups: no treatment control (n = 29), carvedilol (n = 11), voluntary exercise (n = 9), and combination carvedilol and exercise (n = 8). Cardiac function was assessed by echocardiography after 4-wk treatments. Running activity of Alport mice was similar to wild types at 1 mo of age but markedly reduced at 2 mo (1.3 ± 0.40 vs. 4.5 ± 1.02 km/day, P < 0.05). There was a nonsignificant trend for increased running activity at 2 mo by carvedilol in the combination treatment group. Combination treatments conferred increased body weight of Col4a3-/- mice (22.0 ± 1.18 vs. 17.8 ± 0.29 g in untreated mice, P < 0.01), suggesting improved physiology, and heart rates declined by similar increments in all carvedilol-treatment groups. The combination treatment improved systolic parameters; stroke volume (30.5 ± 1.99 vs. 17.8 ± 0.77 μL, P < 0.0001) as well as ejection fraction and global longitudinal strain compared with controls. Myocardial performance index was normalized by all interventions (P < 0.0001). Elevated osteopontin plasma levels in control Alport mice were significantly lowered only by combination treatment, and renal function of the Alport group assessed by urine albumin creatinine ratio was significantly improved by all treatments. The results support synergistic roles for exercise and carvedilol to augment cardiac systolic function of Alport mice with moderately improved renal functions but no change in diastole.NEW & NOTEWORTHY In an Alport mouse model of heart failure with preserved ejection fraction (HFpEF), exercise and carvedilol synergistically improved systolic function without affecting diastole. Carvedilol alone or in combination with exercise also improved kidney function. Molecular analyses indicate that the observed improvements in cardiorenal functions were mediated at least in part by effects on serum osteopontin and related inflammatory cytokine cascades. The work presents new potential therapeutic targets and approaches for HFpEF.

Improvement in Hypertension Management with Pharmacological and Non- Pharmacological Approaches: Current Perspectives

PURPOSE

Improving hypertension management is still one of the biggest challenges in public health worldwide. Existing guidelines do not reach a consensus on the optimal Blood Pressure (BP) target. Therefore, how to effectively manage hypertension based on individual characteristics of patients, combined with the pharmacological and non-pharmacological approach, has become a problem to be urgently considered.

METHODS

Reports published in PubMed that covered Pharmacological and Non-Pharmacological Approaches in subjects taking hypertension management were reviewed by the group independently and collectively. Practical recommendations for hypertension management were established by the panel.

RESULTS

Pharmacological mechanism, action characteristics, and main adverse reactions varied across different pharmacological agents, and patients with hypertension often require a combination of antihypertensive medications to achieve the target BP range. Non-pharmacological treatment provides an additional effective method for improving therapy adherence and long-term BP control, thus reducing the risk of cardiovascular diseases, and slowing down the progression of the disease.

CONCLUSION

This review summarizes the available literature on the most convincing guideline principles, pharmacological treatment, biotechnology interference, interventional surgical treatment, managing hypertension with technical means of big data, Artificial Intelligence and Behavioral Intervention, as well as providing future directions, for facilitating Current and Developing knowledge into clinical implementation.

Complex and Potentially Harmful Medication Patterns in Heart Failure with Preserved Ejection Fraction

BACKGROUND

Complex medication regimens, often present in heart failure with preserved ejection fraction, may increase the risk of adverse drug effects and harm. We sought to characterize this complexity by determining the prevalence of polypharmacy, potentially inappropriate medications, and therapeutic competition (where a medication for 1 condition may worsen another condition) in 1 of the few dedicated heart failure with preserved ejection fraction programs in the United States.

METHODS

We conducted chart review on 231 patients with heart failure with preserved ejection fraction seen in the University of Michigan's Heart Failure with Preserved Ejection Fraction Clinic between July 2016 and September 2019. We recorded: 1) standing medications to determine the presence of polypharmacy, defined as ≥10 medications; 2) potentially inappropriate medications based on the 2016 American Heart Association Scientific Statement on drugs that pose a major risk of causing or exacerbating heart failure, the 2019 Beers Criteria update, or a previously described list of medications associated with geriatric syndromes; and 3) competing conditions and subsequent medications that could create therapeutic competition.

RESULTS

The prevalence of polypharmacy was 74%, and the prevalence of potentially inappropriate medications was 100%. Competing conditions were present in 81% of patients, of whom 49% took a medication that created therapeutic competition.

CONCLUSION

In addition to confirming that polypharmacy was highly prevalent, we found that potentially inappropriate medications and therapeutic competition were also frequently present. This supports the urgent need to develop patient-centered approaches to mitigate the negative effects of complex medication regimens endemic to adults with heart failure with preserved ejection fraction.

Heart Rate-Induced Myocardial Ca2+ Retention and Left Ventricular Volume Loss in Patients With Heart Failure With Preserved Ejection Fraction

Background

Increases in heart rate are thought to result in incomplete left ventricular (LV) relaxation and elevated filling pressures in patients with heart failure with preserved ejection fraction (HFpEF). Experimental studies in isolated human myocardium have suggested that incomplete relaxation is a result of cellular Ca²⁺ overload caused by increased myocardial Na⁺ levels. We tested these heart rate paradigms in patients with HFpEF and referent controls without hypertension.

Methods and Results

In 22 fully sedated and instrumented patients (12 controls and 10 patients with HFpEF) in sinus rhythm with a preserved ejection fraction (≥50%) we assessed left‐sided filling pressures and volumes in sinus rhythm and with atrial pacing (95 beats per minute and 125 beats per minute) before atrial fibrillation ablation. Coronary sinus blood samples and flow measurements were also obtained. Seven women and 15 men were studied (aged 59±10 years, ejection fraction 61%±4%). Patients with HFpEF had a history of hypertension, dyspnea on exertion, concentric LV remodeling and a dilated left atrium, whereas controls did not. Pacing at 125 beats per minute lowered the mean LV end‐diastolic pressure in both groups (controls −4.3±4.1 mm Hg versus patients with HFpEF −8.5±6.0 mm Hg, P=0.08). Pacing also reduced LV end‐diastolic volumes. The volume loss was about twice as much in the HFpEF group (controls −15%±14% versus patients with HFpEF −32%±11%, P=0.009). Coronary venous [Ca²⁺] increased after pacing at 125 beats per minute in patients with HFpEF but not in controls. [Na⁺] did not change.

Conclusions

Higher resting heart rates are associated with lower filling pressures in patients with and without HFpEF. Incomplete relaxation and LV filling at high heart rates lead to a reduction in LV volumes that is more pronounced in patients with HFpEF and may be associated with myocardial Ca²⁺ retention.

Beta-blocker Therapy at Discharge in Patients with Acute Heart Failure and Atrial Fibrillation

BACKGROUND

β-blockers (BBs) are considered primary therapy in stable heart failure (HF) with reduced ejection fraction (HFrEF) without atrial fibrillation (AF); evidence-based benefits of BB on outcome have been documented. However, BBs have not been shown to improve mortality or reduce hospital admissions in HF patients with AF. This study assessed the relationship between BBs at discharge and relevant clinical outcomes in acute heart failure (AHF) patients with AF.

METHODS

From the Korean Acute Heart Failure Registry, 936 HFrEF and 639 HF patients with preserved ejection fraction (HFpEF) and AF were selected. Propensity score (PS) matching accounted for BB selection bias when assessing associations.

RESULTS

BB-untreated patients in the overall cohort of HFrEF and HFpEF had greater deteriorated clinical and laboratory characteristics. In the 670 PS-matched cohort of HFrEF patients, incidences of all clinical events at 60 days and 1 year were not different according to use of BBs. In the 470 PS-matched cohort of HFpEF, rehospitalization and composite outcome at 6 months and 1 year more frequently occurred in non-users of BBs. After adjusting for covariates in the multivariable Cox model of matched cohorts, BB was not associated with clinical outcomes at 60 days and 1 year in HFrEF with AF patients. In HFpEF patients with AF, BB use was associated with reduced 6-month (hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.20-0.74) and 1-year rehospitalization (HR, 0.53; 95% CI, 0.34-0.82).

CONCLUSION

In the HFrEF with AF PS-matched cohort, the use of BBs at discharge was not associated with clinical outcome. However, in HFpEF with AF, the use of BB was associated with reduced rehospitalization during the 6-month and 1-year follow up.

Trends in cause-specific readmissions in heart failure with preserved vs. reduced and mid-range ejection fraction

AIMS

The aim of this study was to investigate whether the readmission of heart failure (HF) patients has decreased over time and how it differs among HF with preserved ejection fraction (EF) (HFpEF) vs. reduced EF (HFrEF) and mid-range EF (HFmrEF).

METHODS AND RESULTS

We evaluated HF patients index hospitalized from January 2004 to December 2011 in the Swedish Heart Failure Registry with 1 year follow-up. Outcome measures were the first occurring all-cause, cardiovascular (CV), and HF readmissions. A total of 20 877 HF patients (11 064 HFrEF, 4215 HFmrEF, and 5562 HFpEF) were included in the study. All-cause readmission was the highest in patients with HFpEF, whereas CV and HF readmissions were the highest in HFrEF. From 2004 to 2011, HF readmission rates within 6 months (from 22.3% to 17.3%, P = 0.003) and 1 year (from 27.7% to 23.4%, P = 0.019) in HFpEF declined, and the risk for 1 year HF readmission in HFpEF was reduced by 7% after adjusting for age and sex (P = 0.022). Likewise, risk factors for HF readmission in HFpEF changed. However, no significant changes were observed in all-cause or CV readmission rates in HFpEF, and no significant changes in cause-specific readmissions were observed in HFrEF. Time to the first readmission did not change significantly from 2004 to 2011, regardless of EF subgroup (all P-values > 0.05).

CONCLUSIONS

Declining temporal trend in HF readmission rates was found in HFpEF, but all-cause readmission still remained the highest in HFpEF vs. HFrEF and HFmrEF. More efforts are needed to reduce the non-HF-related readmission in patients with HFpEF.

Effect of ivabradine on exercise capacity in individuals with heart failure with preserved ejection fraction

The prevalence of heart failure with preserved ejection fraction (HFpEF) is about 30-75% of the patients living with heart failure. A hallmark symptom of these patients is exercise intolerance. Ivabradine can, eventually, increase exercise capacity by heart rate control. However, clinical trials show conflicting results about the effects of ivabradine on exercise capacity, an important prognostic variable. The aim of this study was to investigate the effects of ivabradine on exercise capacity in individuals with HFpEF. This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and supplemented by guidance from the Cochrane Collaboration Handbook for Systematic Reviews of Interventions. For the meta-analysis, a forest plot was used to graphically present the effect sizes and the 95% CIs. Four randomized controlled trials were included. Ivabradine did not change exercise capacity expressed by peak VO₂ and 6MWT (MD = 0.8; 95% CI - 2.5 to 4.3; P = 0.62) (Fig. 4a). In our secondary analysis, the ivabradine group showed a significant resting HR reduction when compared with placebo (MD = - 13.2; 95% CI - 16.6 to -9.8; P < 0.00001) and ivabradine showed increased values of E/e' ratio compared with placebo (MD = 0.8; 95% CI 0.0 to 1.6; P = 0.04). Current available evidence suggests that there is no effect of ivabradine on exercise capacity in patients with HFpEF. Also, questions about negative effects on E/e' values and adverse events associated with ivabradine treatment need to be considered in future studies.

[Frequency of use and Indications for Beta-Blockers in Heart Failure with Preserved Ejection Fraction]

Aim      To evaluate trends in beta-blocker prescribing and incidence of possible reasons for beta-blocker administration, including arterial hypertension (AH), atrial fibrillation (AF), ischemic heart disease (IHD), and myocardial infarction, in participants of clinical studies enrolling patients with chronic heart failure with preserved ejection fraction (CHF-PEF).Material and methods  A systematic literature search was performed in the PubMed and EMBASE databases. The study included RCSs of pharmacological therapies for patients with CHF-PEF conducted from 1993 through 2019. Studies of beta-blocker efficacy or those including a specific population (CHF-PEF+IHD or CHF-PEF+AH, etc.) were excluded from the analysis. Baseline characteristics of patients, incidence rate of beta-blocker prescribing, and prevalence of AH, AF, IHD, and MI were recorded. Trends in prevalence of concomitant diseases and the proportion of patients using beta-blockers by the year of enrollment to the study were analyzed with the Mann-Kendall test.Results 14 RCSs of 718 selected publications completely met the inclusion and exclusion criteria. Beta-blocker prescribing significantly increased between 1993 and 2019 (tau=0.51; p=0.014) and reached 80 % in recent studies. Furthermore, prevalence of IHD, MI, AH, and AF did not significantly change among the RCS participants (p&gt;0.05 for all). However, while for AH and AF, a tendency toward an increasing prevalence (tau=0.4; p=0.055 and tau=0.043; p=0.063, respectively) could be considered and became statistically significant for AF when the ALDO-DHF study was excluded from the analysis (tau=0.5; p=0.042), the MI prevalence tended to decrease (tau= -0.73; p=0.06).Conclusion      Beta-blocker prescribing to patients upon inclusion into RCSs for CHF-PEF has significantly increased for the recent 20 years while the incidence of formal reasons for beta-blocker administration (AF, AH, MI, IHD) did not significantly change.