Heart failure with preserved vs reduced ejection fraction following cardiac rehabilitation: impact of endothelial function

Exercise may not just be good for sleep; It can also help lower cardiovascular event risk

Cardiovascular diseases (CVD) stand at the forefront of global mortality, presenting an immense and urgent public health challenge on a global scale. Effectively addressing the associated risk factors is pivotal in not only preventing but also stabilizing and potentially reversing the progression of these conditions. Emerging research illuminates a compelling correlation between sleep disorders and CVD. Clinically, individuals afflicted with existing CVD or those possessing risk factors frequently grapple with sleep disturbances, exacerbating their conditions, particularly in severe cases where disease progression is accelerated. Even among ostensibly healthy individuals, chronic sleep deprivation exacts a toll on cardiovascular function. The strategic implementation of exercise interventions emerges as a potent tool in enhancing sleep quality, surpassing the efficacy of pharmaceutical treatments. Furthermore, the maintenance of optimal sleep patterns significantly contributes to lowering the risk of cardiovascular diseases. This comprehensive review delves deeply into the intricate relationship between exercise and the amelioration of cardiovascular disease risk associated with sleep. Moreover, it meticulously elucidates the complex mechanisms through which exercise operates, effectively reducing cardiovascular disease risk from the unique perspective of sleep science.

Cardiac rehabilitation utilization, barriers, and outcomes among patients with heart failure

Exercise-based cardiac rehabilitation (CR) is effective for improving both primary (i.e., mortality and hospitalizations) and secondary (i.e., functional capacity and quality of life among) clinical outcomes among patients with heart failure (HF). The mechanisms that explain these benefits are complex and are linked to exercise adaptations such as central and peripheral hemodynamics combined with improved overall medical management. Despite the benefits of CR, utilization rates are low among CR eligible patients. Clinician-, patient-, and health system-related barriers have been identified as primary factors contributing to the lack of CR utilization among HF patients. These include patient referrals (clinician-related), psychosocial factors (patient-related), and patient access to CR services (health system-related). The aims of this review are to detail the components of each barrier as well as identify evidence-based strategies to improve CR utilization and adherence among HF. The improvements in primary and secondary outcomes along with the mechanisms that are linked to these changes will also be examined.

Cardiac rehabilitation in heart failure with severely reduced ejection fraction: effects on mortality

Thirty years ago, patients with low ejection fraction (EF) have often been excluded from rehabilitation programs due to concern about possibility of sudden death or other adverse cardiovascular events during exercise sessions. Recent studies have highlighted the fact that cardiac rehabilitation could improve exercise capacity, cardiac function, and health-related quality of life in congestive heart failure patients. This encouraged us to write a review article and update our latest knowledge about the outcome of rehabilitation program in patients with severely depressed cardiac function. We were particularly interested in effect of cardiac rehabilitation on exercise capacity, quality of life, vascular effects, neuro-hormonal changes, and mortality. We also conducted a mini-systematic review and meta-analysis on randomized controlled trials comparing exercise training with usual care in patients with severely reduced left ventricular ejection fraction, for the mortality subsection to obtain precise estimates of overall treatment benefit on mortality. It is our privilege to submit our manuscript for possible publication in your prestigious journal.

Current Management of Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) encompasses nearly half of heart failure (HF) worldwide, and still remains a poor prognostic indicator. It commonly coexists in patients with vascular disease and needs to be recognized and managed appropriately to reduce morbidity and mortality. Due to the heterogeneity of HFpEF as a disease process, targeted pharmacotherapy to this date has not shown a survival benefit among this population. This article serves as a comprehensive historical review focusing on the management of HFpEF by reviewing past, present, and future randomized controlled trials that attempt to uncover a therapeutic value. With a paradigm shift in the pathophysiology of HFpEF as an inflammatory, neurohormonal, and interstitial process, a phenotypic approach has increased in popularity focusing on the treatment of HFpEF as a systemic disease. This article also addresses common comorbidities associated with HFpEF as well as current and ongoing clinical trials looking to further elucidate such links.

Cardiovascular responses to high-intensity stair climbing in individuals with coronary artery disease

Exercise‐based cardiac rehabilitation leads to improvements in cardiovascular function in individuals with coronary artery disease. The cardiac effects of coronary artery disease (CAD) can be quantified using clinical echocardiographic measures, such as ejection fraction (EF). Measures of cardiovascular function typically only used in research settings can provide additional information and maybe more sensitive indices to assess changes after exercise‐based cardiac rehabilitation. These additional measures include endothelial function (measured by flow‐mediated dilation), left ventricular twist, myocardial performance index, and global longitudinal strain. To investigate the cardiovascular response to 12 week of either traditional moderate‐intensity (TRAD) or stair climbing‐based high‐intensity interval (STAIR) exercise‐based cardiac rehabilitation using both clinical and additional measures of cardiovascular function in individuals with CAD. Measurements were made at baseline (BL) and after supervised (4wk) and unsupervised (12 week) of training. This study was registered as a clinical trial at clinicaltrials.gov (NCT03235674). Participants were randomized into either TRAD (n = 9, 8M/1F) and STAIR (n = 9, 8M/1F). There was a training‐associated increase in one component of left ventricular twist: Cardiac apical rotation (TRAD: BL: 5.6 ± 3.3º, 4 week: 8.0 ± 3.9º, 12 week: 6.2 ± 5.1º and STAIR: BL: 5.1 ± 3.6º, 4 week: 7.4 ± 3.9º, 12 week: 7.8 ± 2.8º, p (time) = 0.03, η² = 0.20; main effect) and post‐hoc analysis revealed a difference between BL and 4 week (p = 0.02). There were no changes in any other clinical or additional measures of cardiovascular function. The small increase in cardiac apical rotation observed after 4 weeks of training may indicate an early change in cardiac function. A larger overall training stimulus may be needed to elicit other cardiovascular function changes.

Mechanisms and Clinical Implications of Endothelial Dysfunction in Arterial Hypertension

The endothelium is composed of a monolayer of endothelial cells, lining the interior surface of blood and lymphatic vessels. Endothelial cells display important homeostatic functions, since they are able to respond to humoral and hemodynamic stimuli. Thus, endothelial dysfunction has been proposed as a key and early pathogenic mechanism in many clinical conditions. Given the relevant repercussions on cardiovascular risk, the complex interplay between endothelial dysfunction and systemic arterial hypertension has been a matter of study in recent years. Numerous articles have been published on this issue, all of which contribute to providing an interesting insight into the molecular mechanisms of endothelial dysfunction in arterial hypertension and its role as a biomarker of inflammation, oxidative stress, and vascular disease. The prognostic and therapeutic implications of endothelial dysfunction have also been analyzed in this clinical setting, with interesting new findings and potential applications in clinical practice and future research. The aim of this review is to summarize the pathophysiology of the relationship between endothelial dysfunction and systemic arterial hypertension, with a focus on the personalized pharmacological and rehabilitation strategies targeting endothelial dysfunction while treating hypertension and cardiovascular comorbidities.

Heart rate recovery is useful for evaluating the recovery of exercise tolerance in patients with heart failure and atrial fibrillation

This study aimed to examine the factors that contribute to improvement of exercise tolerance in patients with heart failure (HF) and atrial fibrillation (AF) following cardiac rehabilitation. Our hypothesis is that parasympathetic values are important for recovering exercise tolerance in those patients. We included 84 consecutive patients with HF and AF (mean age: 69 ± 15 years, 80% men). All of the patients underwent a cardiopulmonary exercise test and had pre and post 5 month cardiac rehabilitation assessed. After 155 ± 11 days and 44 ± 8 sessions, 73 patients (86%) showed an increase in peak oxygen uptake (VO₂) and VO₂ at the anaerobic threshold. In univariate linear regression analysis, the % change in heart rate recovery, plasma B-type natriuretic peptide levels, resting heart rate, and the minute ventilation /carbon dioxide output slope were significantly related to that of peak VO₂ (p < 0.01, p = 0.03, p = 0.02, p < 0.01, respectively). Stepwise multivariate linear regression analysis showed that the % change in heart rate recovery was independently related to that of peak VO₂ (p < 0.05). Our results suggest that heart rate recovery is closely associated with recovery of exercise tolerance in patients with HF and AF after CR.

Improvements in exercise tolerance with an exercise intensity above the anaerobic threshold in patients with acute myocardial infarction

Anaerobic threshold (AT) from cardiopulmonary exercise tests (CPX) is the standard for measuring exercise intensity among patients with cardiovascular disease in Japan. However, it remains controversial whether AT represents the safety limit for exercise intensity in patients with cardiovascular disease. The purpose of this study was to investigate cardiac rehabilitation (CR) efficacy and safety with exercise intensities above the AT and at a traditional AT in a randomized trial. The participants included 57 patients who were admitted to the outpatient CR unit with a diagnosis of acute myocardial infarction. The participants were randomly divided as follows: 25 patients in the AT group, who performed aerobic exercises with an intensity at the AT; and 32 patients in the "Over AT" group, who performed exercises at an intensity higher than the AT. The following components were measured: maximum oxygen uptake (peak VO₂), oxygen uptake at the AT (AT VO₂), increase in oxygen uptake during exercise (ΔVO₂/ΔWR) during the CPX, vascular endothelial function test (%FMD: the percentage of flow-mediated dilation), and isometric knee extension strength. The measurements were obtained at the start of the exercise therapy and after 2, 3, and 4 months. They were compared within and between groups, and the correlation between the rates of improvement was investigated. Peak VO₂, AT VO₂, ΔVO₂/ΔWR, and %FMD had significantly improved after 3 months in both groups. The isometric knee extension strength had improved in the "Over AT" group after 2 months. Interactions were observed with peak VO₂, ΔVO₂/ΔWR, and isometric knee extension strength. However, %FMD was not significantly different between the groups. In the "Over AT" group, the rate of improvement in peak VO₂ was positively correlated with the improvement in the isometric knee extension strength (r = 0.61, p < 0.001), but not with %FMD. These data suggest that exercise at an intensity above the AT improved exercise tolerance faster than that at the AT, and this improvement rate was associated with changes in isometric knee extension strength.

The Diagnostic and Therapeutic Value of Multimarker Analysis in Heart Failure. An Approach to Biomarker-Targeted Therapy

Background: Heart failure is a pathophysiological state, which is still associated with high morbidity and mortality despite established therapies. Diverse well-known biomarkers fail to assess the variety of individual pathophysiology in the context of heart failure.

Methods: An analysis of prospective, multimarker-specific therapeutic approaches to heart failure based on studies in current literature was performed. A total of 159 screened publications in the field of biomarkers in heart failure were hand-selected and found to be eligible for this study by a team of experts.

Results: Established biomarkers of the inflammatory axis, matrix remodeling, fibrosis and oxidative stress axis, as well as potential therapeutic interventions were investigated. Interaction with end organs, such as cardio-hepatic, cardio-renal and cardio-gastrointestinal interactions show the complexity of the syndrome and could be of further therapeutic value. MicroRNAs are involved in a wide variety of physiologic and pathophysiologic processes in heart failure and could be useful in diagnostic as well as therapeutic setting.

Conclusion: Based on our analysis by a biomarker-driven approach in heart failure therapy, patients could be treated more specifically in long term with a consideration of different aspects of heart failure. New studies evaluating a multimarker – based therapeutic approach could lead in a decrease in the morbidity and mortality of heart failure patients.

Effectiveness and safety of Baduanjin exercise (BDJE) on heart failure with preserved left ventricular ejection fraction (HFpEF): A protocol for systematic review and meta-analysis

BACKGROUND

Nearly half of the heart failure (HF) patients have been classified as HF with preserved left ventricular ejection fraction (HFpEF) and the prevalence has been increasing over time. The subject of this study is to assess the clinical effectiveness and safety of Baduanjin exercise (BDJE), as a kind of traditional Chinese exercises, for HFpEF patients.

METHODS

A systematic literature search for articles up to September 2020 will be performed in following electronic databases: PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP) Database, Chinese Biomedical Database (CBM), Chinese Biomedical Literature Service System (SinoMed) and Wanfang Database. Inclusion criteria are randomized controlled trials of BDJE applied on HFpEF patients. The primary outcome measures will be exercise capacity (cardiopulmonary exercise test or 6-minute walking test) and quality of life. The secondary outcomes will be as the following: blood pressure, heart rate, echocardiography, endothelial function, arterial stiffness and hypersensitive C-reactive protein and N-Terminal pro-B-type natriuretic peptide. The safety outcome measures will be adverse events, liver and kidney function. RevMan 5.3 software will be used for data synthesis, sensitivity analysis, subgroup analysis and risk of bias assessment. A funnel plot will be developed to evaluate reporting bias. Stata 12.0 will be used for meta-regression and Egger tests. We will use the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to assess the quality of evidence.

CONCLUSION

The study will give an explicit evidence to evaluate the effectiveness and safety of BDJE for HFpEF patients.

ETHICS AND DISSEMINATION

This systematic review does not require ethics approval and will be submitted to a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42020200324.

Endothelial dysfunction and the risk of heart failure in a community-based study: the Multi-Ethnic Study of Atherosclerosis

Aims

We aimed to investigate the association between endothelial dysfunction, assessed by brachial flow‐mediated dilation (FMD), and the incidence of heart failure (HF) in the community‐based Multi‐Ethnic Study of Atherosclerosis.

Methods and results

Brachial artery FMD was measured in a nested case‐cohort sample including 3496 of 6814 Multi‐Ethnic Study of Atherosclerosis participants without prevalent cardiovascular disease (mean age 61 years, 50% women). Multivariable probability‐weighted Cox proportional hazards analysis was used to examine the association between FMD and incident HF. We also investigated the association between FMD and HF with reduced vs. preserved ejection fraction [HFrEF (left ventricular ejection fraction <45%) vs. HFpEF (left ventricular ejection fraction ≥45%)]. During follow‐up (median 12 years), 149 participants developed incident HF (incidence rate 3.7 events per 1000 person years). There were 56 HFrEF and 69 HFpEF events (incidence rates 1.4 and 1.7 events per 1000 person years, respectively). In multivariable models adjusted for established HF risk factors (age, sex, race/ethnicity, body mass index, systolic blood pressure, antihypertensive treatment, heart rate, diabetes mellitus, history of myocardial infarction, current smoker, and former smoker status), individuals in the highest quartile of FMD (reflecting better endothelial function) had a lower HF risk compared with individuals in the lowest quartile [hazard ratio 0.53, 95% confidence interval (CI) 0.31–0.95]. Lower risk according to higher FMD was particularly evident for HFrEF, but not for HFpEF (hazard ratio per standard deviation increase 0.79, 95% CI 0.64–0.97 vs. 0.99, 95% CI 0.78–1.26, respectively). Results remained similar after adjustment for baseline natriuretic peptide levels. The addition of FMD to established HF risk factors generally rendered no or only modest improvement in C‐statistics [C‐statistics for model with established HF risk factors: 0.774, and with the addition of FMD: 0.776 (delta C 0.002, 95% confidence interval −0.002 to 0.006)].

Conclusions

Endothelial dysfunction was independently associated with HF in this community cohort, suggesting a pathophysiological contribution of endothelial function to the development of HF, in particular HFrEF. However, the value of FMD measurements for HF risk prediction seems limited.

Cardiac Rehabilitation and Endothelial Function

Endothelial dysfunction is an early abnormality in the process of atherosclerosis and cardiovascular disease and has been associated with worse clinical outcome. Cardiac rehabilitation (CR) has been reported to be helpful to reduce cardiovascular events in various types of cardiac disease, but the mechanisms of its beneficial effects remain only partially known. In this article, we review the studies that assessed the effect of CR on endothelial function in patients with various cardiac conditions. Available data show that CR significantly improves impaired endothelial function in these patients, which may contribute to the beneficial effects of CR on clinical outcome.

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.

Impact of acute antioxidant administration on inflammation and vascular function in heart failure with preserved ejection fraction

Although it is now well established that heart failure with preserved ejection fraction (HFpEF) is associated with marked inflammation and a prooxidant state that is accompanied by vascular dysfunction, whether acute antioxidant (AO) administration can effectively target these disease-related decrements has not been evaluated. Thus, the present study sought to evaluate the efficacy of an acute over-the-counter AO cocktail (600 mg α-lipoic acid, 1,000 mg vitamin C, and 600 IU vitamin E) to mitigate inflammation and oxidative stress, and subsequently improve nitric oxide (NO) bioavailability and vascular function, in patients with HFpEF. Flow-mediated dilation (FMD) and reactive hyperemia (RH) were evaluated to assess conduit vessel and microvascular function, respectively, 90 min after administration of either placebo (PL) or AO in 16 patients with HFpEF (73 ± 10 yr, EF 54-70%) using a double-blind, crossover design. Circulating biomarkers of inflammation (C-reactive protein, CRP), oxidative stress (malondialdehyde and protein carbonyl), free radical concentration (EPR spectroscopy), antioxidant capacity, ascorbate and NO bioavailability (plasma nitrate, [Formula: see text], and nitrite, [Formula: see text]) were also assessed. FMD improved following AO administration (PL: 3.49 ± 0.7%, AO: 5.83 ± 1.0%), whereas RH responses were similar between conditions (PL: 428 ± 51 mL, AO: 425 ± 51 mL). AO administration decreased CRP (PL: 4,429 ± 705 ng/mL, AO: 3,664 ± 520 ng/mL) and increased ascorbate (PL: 30.0 ± 2.9 µg/mL, AO: 45.1 ± 3.7 µg/mL) and [Formula: see text] (PL: 182 ± 21 nM, AO: 213 ± 24 nM) but did not affect other biomarkers. Together, these data suggest that acute AO administration can exert anti-inflammatory effects and improve conduit artery vasodilation, but not microvascular function, in patients with HFpEF.

Endothelial Dysfunction in Chronic Heart Failure: Assessment, Findings, Significance, and Potential Therapeutic Targets

Chronic heart failure (CHF) is a complex syndrome that results from structural and functional disturbances that affect the ability of the heart to supply oxygen to tissues. It largely affects and reduces the patient's quality of life, socio-economic status, and imposes great costs on health care systems worldwide. Endothelial dysfunction (ED) is a newly discovered phenomenon that contributes greatly to the pathophysiology of numerous cardiovascular conditions and commonly co-exists with chronic heart failure. However, the literature lacks clarity as to which heart failure patients might be affected, its significance in CHF patients, and its reversibility with pharmacological and non-pharmacological means. This review will emphasize all these points and summarize them for future researchers interested in vascular pathophysiology in this particular patient population. It will help to direct future studies for better characterization of these two phenomena for the potential discovery of therapeutic targets that might reduce future morbidity and mortality in this "at risk" population.

Rethinking Endothelial Dysfunction as a Crucial Target in Fighting Heart Failure

Endothelial dysfunction is characterized by nitric oxide dysregulation and an altered redox state. Oxidative stress and inflammatory markers prevail, thus promoting atherogenesis and hypertension, important risk factors for the development and progression of heart failure. There has been a reemerging interest in the role that endothelial dysfunction plays in the failing circulation. Accordingly, patients with heart failure are being clinically assessed for endothelial dysfunction via various methods, including flow-mediated vasodilation, peripheral arterial tonometry, quantification of circulating endothelial progenitor cells, and early and late endothelial progenitor cell outgrowth measurements. Although the mechanisms underlying endothelial dysfunction are intimately related to cardiovascular disease and heart failure, it remains unclear whether targeting endothelial dysfunction is a feasible strategy for ameliorating heart failure progression. This review focuses on the pathophysiology of endothelial dysfunction, the mechanisms linking endothelial dysfunction and heart failure, and the various diagnostic methods currently used to measure endothelial function, ultimately highlighting the therapeutic implications of targeting endothelial dysfunction for the treatment of heart failure.

Real-world presentation with heart failure in primary care: do patients selected to follow diagnostic and management guidelines have better outcomes?

Objective

To describe associations between initial management of people presenting with heart failure (HF) symptoms in primary care, including compliance with the recommendations of the National Institute for Health and Care Excellence (NICE), and subsequent unplanned hospitalisation for HF and death.

Methods

This is a retrospective cohort study using data from general practices submitting records to the Clinical Practice Research Datalink. The cohort comprised patients diagnosed with HF during 2010–2013 and presenting to their general practitioners with breathlessness, fatigue or ankle swelling.

Results

13 897 patients were included in the study. Within the first 6 months, only 7% had completed the NICE-recommended pathway; another 18.6% had followed part of it (B-type natriuretic peptide testing and/or echocardiography, or specialist referral). Significant differences in hazards were seen in unadjusted analysis in favour of full or partial completion of the NICE-recommended pathway. Covariate adjustment attenuated the relations with death much more than those for HF admission. Compared with patients placed on the NICE pathway, treatment with HF medications had an HR of 1.16 (95% CI 1.05 to 1.28, p=0.003) for HF admission and 1.03 (95% CI 0.90 to 1.17, p= 0.674) for death. Patients who partially followed the NICE pathway had similar hazards to those who completed it. Patients on no pathway had the highest hazard for HF admission at 1.30 (95% 1.18 to 1.43, p<0.001) but similar hazard for death.

Conclusions

Patients not put on at least some elements of the NICE-recommended pathway had significantly higher risk of HF admission but non-significant higher risk of death than other patients had.