Role and benefits of exercise in the management of patients with heart failure

Heart Failure in Cardiac Rehabilitation: A REVIEW AND PRACTICAL CONSIDERATIONS

PURPOSE

Exercise cardiac rehabilitation (CR) represents an evidence-based therapy for patients with heart failure with reduced ejection fraction (HFrEF) and this article provides a concise review of the relevant exercise testing and CR literature, including aspects unique to their care.

CLINICAL CONSIDERATIONS

A hallmark feature of HFrEF is exercise intolerance (eg, early-onset fatigue). Drug therapies for HFrEF target neurohormonal pathways to blunt negative remodeling of the cardiac architecture and restore favorable loading conditions. Guideline drug therapy includes β-adrenergic blocking agents; blockade of the renin-angiotensin system; aldosterone antagonism; sodium-glucose cotransport inhibition; and diuretics, as needed.

EXERCISE TESTING AND TRAINING

Various assessments are used to quantify exercise capacity in patients with HFrEF, including peak oxygen uptake measured during an exercise test and 6-min walk distance. The mechanisms responsible for the exercise intolerance include abnormalities in ( a ) central transport (chronotropic response, stroke volume) and ( b ) the diffusion/utilization of oxygen in skeletal muscles. Cardiac rehabilitation improves exercise capacity, intermediate physiologic measures (eg, endothelial function and sympathetic nervous system activity), health-related quality of life (HRQoL), and likely clinical outcomes. The prescription of exercise in patients with HFrEF is generally similar to that for other patients with cardiovascular disease; however, patients having undergone an advanced surgical therapy do present with features that require attention.

SUMMARY

Few patients with HFrEF enroll in CR and as such, many miss the derived benefits, including improved exercise capacity, a likely reduction in risk for subsequent clinical events (eg, rehospitalization), improved HRQoL, and adoption of disease management strategies.

The benefit of exercise-based rehabilitation programs in patients with pulmonary hypertension: a systematic review and meta-analysis of randomized controlled trials

Several studies have suggested that exercise capacity and quality of life are reduced in patients with pulmonary hypertension, and exercise-based rehabilitation can improve exercise capacity and quality of life in patients with pulmonary hypertension. The aim of this study is to assess the efficacy and safety of exercise-based rehabilitation in patients with pulmonary hypertension through a meta-analysis of randomized controlled trials. We searched PubMed, Embase, Medline, and the Cochrane Central Register of Controlled Trials up to November 2018. All randomized controlled trials comparing exercise capacity and quality of life between patients undergoing exercise-based rehabilitation and those undergoing non-exercise training were included. Data were extracted separately and independently by two investigators, and discrepancies were arbitrated by the third investigator. We used the random-effects model to analyze the results, the GRADE to assess the risk of bias in the included studies, and I² statistic to estimate the degree of heterogeneity. Nine randomized controlled trials are included; however, only seven randomized controlled trials were able to extract data. Including inpatients and outpatients, the total number of participants was 234, most of whom were diagnosed as pulmonary artery hypertension. The study duration ranged from 3 to 15 weeks. The mean six-minute walking distance after exercise training was 51.94 m higher than control (27.65-76.23 m, n = 234, 7 randomized controlled trials, low quality evidence), the mean peak oxygen uptake was 2.96 ml/kg/min higher (2.49-3.43 ml/kg/min, n = 179, 4 randomized controlled trials, low-quality evidence) than in the control group. In conclusion, our finding suggests that an exercise-based training program positively influences exercise capacity in patients with pulmonary hypertension.

Translational neurocardiology: preclinical models and cardioneural integrative aspects

Neuronal elements distributed throughout the cardiac nervous system, from the level of the insular cortex to the intrinsic cardiac nervous system, are in constant communication with one another to ensure that cardiac output matches the dynamic process of regional blood flow demand. Neural elements in their various 'levels' become differentially recruited in the transduction of sensory inputs arising from the heart, major vessels, other visceral organs and somatic structures to optimize neuronal coordination of regional cardiac function. This White Paper will review the relevant aspects of the structural and functional organization for autonomic control of the heart in normal conditions, how these systems remodel/adapt during cardiac disease, and finally how such knowledge can be leveraged in the evolving realm of autonomic regulation therapy for cardiac therapeutics.

Acute effects of low-level laser therapy irradiation on blood lactate and muscle fatigue perception in hospitalized patients with heart failure-a pilot study

The objective of the present study is to evaluate the acute effects of low-level laser therapy (LLLT) on functional capacity, perceived exertion, and blood lactate in hospitalized patients with heart failure (HF). Patients diagnosed with systolic HF (left ventricular ejection fraction <45 %) were randomized and allocated prospectively into two groups: placebo LLLT group (n = 10)-subjects who were submitted to placebo laser and active LLLT group (n = 10)-subjects who were submitted to active laser. The 6-min walk test (6MWT) was performed, and blood lactate was determined at rest (before LLLT application and 6MWT), immediately after the exercise test (time 0) and recovery (3, 6, and 30 min). A multi-diode LLLT cluster probe (DMC, São Carlos, Brazil) was used. Both groups increased 6MWT distance after active or placebo LLLT application compared to baseline values (p = 0.03 and p = 0.01, respectively); however, no difference was observed during intergroup comparison. The active LLLT group showed a significant reduction in the perceived exertion Borg (PEB) scale compared to the placebo LLLT group (p = 0.006). In addition, the group that received active LLLT showed no statistically significant difference for the blood lactate level through the times analyzed. The placebo LLLT group demonstrated a significant increase in blood lactate between the rest and recovery phase (p < 0.05). Acute effects of LLLT irradiation on skeletal musculature were not able to improve the functional capacity of hospitalized patients with HF, although it may favorably modulate blood lactate metabolism and reduce perceived muscle fatigue.

Effect of exercise training on renal function and renal aquaporin-2 expression in rats with chronic heart failure

1. Chronic heart failure (CHF) is often accompanied by renal dysfunction. Exercise training may relieve the symptomatic burden and improve the overall prognosis of CHF. In the present study, the effects of exercise training on renal function and renal aquaporin (AQP)-2 expression in CHF rats were examined to determine whether exercise training could relieve renal dysfunction in CHF rats. 2. Male Sprague-Dawley rats were divided into three groups: sham, sedentary CHF (Sed-CHF) and exercise training CHF (Ex-CHF) groups. Cardiorenal function was assessed in each group by haemodynamic measurement and ultraviolet spectrophotometry. Pathological changes in cardiac and renal tissues were evaluated histologically and the collagen volume fraction (CVF) was calculated. The expressions of AQP-2 and β-tubulin were determined by western blotting and immunohistochemistry. 3. The Sed-CHF rats were found to have increased left ventricular end-diastolic pressure (LVEDP) and CVF in the heart compared with sham rats. Exercise training decreased LVEDP and CVF values in Ex-CHF rats. The Sed-CHF rats were found to have increased serum levels of creatinine (sCr), blood urea nitrogen (BUN) and arginine vasopressin (AVP), as well as increased CVF in the kidney, compared with sham rats. Exercise training decreased levels of sCr, BUN, AVP and CVF in Ex-CHF rats. Moreover, exercise training decreased AQP-2 and β-tubulin protein expression in the kidney of CHF rats. 4. The results suggest that exercise training can significantly improve the renal dysfunction in CHF rats and that the underlying mechanism may be related to water reabsorption and preventing changes to the cytoskeleton.

Exergaming in older adults: a scoping review and implementation potential for patients with heart failure

Background:

Physical activity can improve exercise capacity, quality of life and reduce mortality and hospitalization in patients with heart failure (HF). Adherence to exercise recommendations in patients with HF is low. The use of exercise games (exergames) might be a way to encourage patients with HF to exercise especially those who may be reluctant to more traditional forms of exercise. No studies have been conducted on patients with HF and exergames.

Aim:

This scoping review focuses on the feasibility and influence of exergames on physical activity in older adults, aiming to target certain characteristics that are important for patients with HF to become more physically active.

Methods:

A literature search was undertaken in August 2012 in the databases PsychInfo, PUBMED, Scopus, Web of Science and CINAHL. Included studies evaluated the influence of exergaming on physical activity in older adults. Articles were excluded if they focused on rehabilitation of specific limbs, improving specific tasks or describing no intervention. Fifty articles were found, 11 were included in the analysis.

Results:

Exergaming was described as safe and feasible, and resulted in more energy expenditure compared to rest. Participants experienced improved balance and reported improved cognitive function after exergaming. Participants enjoyed playing the exergames, their depressive symptoms decreased, and they reported improved quality of life and empowerment. Exergames made them feel more connected with their family members, especially their grandchildren.

Conclusion:

Although this research field is small and under development, exergaming might be promising in order to enhance physical activity in patients with HF. However, further testing is needed.

Should high-intensity-aerobic interval training become the clinical standard in heart failure?

Aerobic exercise training in the heart failure (HF) population is supported by an extensive body of literature. The clinically accepted model for exercise prescription is currently moderate-intensity-aerobic continuous training (MI-ACT). Documented benefits from the literature include improvements in various aspects of physiologic function, aerobic exercise capacity and quality of life while the impact on morbidity and mortality is promising but requires further investigation. Recently, however, a body of evidence has begun to emerge demonstrating high-intensity-aerobic interval training (HI-AIT) can be performed safely with impressive improvements in physiology, functional capacity and quality of life. These initial findings have led some to question the long-standing clinical approach to aerobic exercise training in patients with HF (i.e., MI-ACT), implying it should perhaps be replaced with a HI-AIT model. This is a potentially controversial paradigm shift given the potential increase in adverse event risk associated with exercising at higher intensities, particularly in the HF population where the likelihood of an untoward episode is already at a heightened state relative to the apparently healthy population. The present review therefore addresses key issues related to HI-AIT in the HF population and makes recommendations for future research and current clinical practice.

Perturbations in skeletal muscle sarcomere structure in patients with heart failure and Type 2 diabetes: restorative effects of (−)-epicatechinrich cocoa

HF (heart failure) and T2D (Type 2 diabetes) associate with detrimental alterations in SkM (skeletal muscle) structure/function. We have demonstrated recently that (−)-ERC (epicatechin-rich cocoa) improves SkM mitochondrial structure [Taub, Ramirez-Sanchez, Ciaraldi, Perkins, Murphy, Naviaux, Hogan, Ceballos, Maisel, Henry et al. (2012) Clin. Trans. Sci. 5, 43–47]. We hypothesized that an improved mitochondrial structure may facilitate the reversal of detrimental alterations in sarcomeric microstructure. In a pilot study, five patients with HF and T2D consumed ERC for 3 months; treadmill testing [V̇O2max (maximum oxygen consumption)] and SkM biopsies were performed. Western blot analysis, immunohistochemistry and electron microscopy were used. We report severe perturbations in components of the DAPC (dystrophin-associated protein complex) as well as sarcomeric microstructure at baseline. ERC induced recovery/enhancement of DAPC protein levels, sarcomeric microstructure and, in a co-ordinated fashion, alterations in markers of SkM growth/differentiation consistent with myofibre regeneration. V̇O2max increased (~24%) but did not reach statistical significance. These initial results warrant further rigorous investigation, since the use of ERC (or pure epicatechin) may represent a safe and novel means of improving muscle function.

Effects of exercise interventions on peripheral vascular endothelial vasoreactivity in patients with heart failure with reduced ejection fraction

Changes in vascular function, such as endothelial dysfunction are linked to the progression of heart failure (HF) and poorer outcomes, such as increased hospitalisations. Exercise training may positively influence endothelial function in HF patients with reduced ejection fraction. The aim of this manuscript is to summarise HF studies evaluating the influence of exercise training on endothelial function as measured by flow mediated vasodilation as a primary outcome and to provide recommendations for future research studies designed to improve peripheral vascular function in HF. Databases were searched for studies published between 1995 and December 2011. Two reviewers determined eligibility and extracted information on study characteristics and quality, exercise interventions, and endothelial function. Eleven articles (N=318 HF participants with an ejection fraction <40%) were eligible for full review. Aerobic, resistance, or combined exercise training improved endothelium-dependent vasodilation as measured by ultrasound or plethysmography. There is less evidence supporting improvement in endothelium-independent function with exercise training. Sample sizes were small and predominantly male. Future research is needed to address the best mode and optimal dose of exercise for all patients with HF including women and subgroups with specific co-morbidities.

Effect of acute exercise on cardiovascular hemodynamic and red blood cell concentrations of purine nucleotides in hypertensive compared with normotensives rats

OBJECTIVE

The mechanisms of exercise-induced health benefits are complex and not fully understood. This study investigated the effects of exercise and hypertension on cardiovascular hemodynamic responses and red blood cell (RBC) concentrations of purine nucleotides using normotensive and hypertensive rat models in vivo.

METHODS

Sprague Dawley rats (SDRs) and spontaneously hypertensive rats (SHRs) were exercised on a treadmill for 15 min at a speed of 10 m/min and 5% grade. Blood samples were obtained from each rat before, during, and after exercise for measurement of adenosine 5'-triphosphate (ATP) and guanosine 5'-triphosphate (GTP) concentrations in RBCs by a validated high-performance liquid chromatography assay. They were returned to a restrainer after exercise, and hemodynamic recording collected continuously up to 6 h. Two separate groups (SDRs and SHRs) without exercise were used as controls. Biomarker data were compared between SDRs and SHRs using analysis of variance and t test and difference considered significant at p < 0.05.

RESULTS

The study has demonstrated for the first time a difference in the postexercise effect between SDRs and SHRs. The 15 min of exercise significantly increased systolic blood pressure (SBP) (129 ± 16 to 162 ± 26 mmHg) and heart rate (HR) (416 ± 29 to 491 ± 26 bpm) in SDRs (p < 0.05), but not in SHRs. The postexercise hemodynamic effects were more profound in SHRs. SBP and diastolic blood pressure (DBP) also fell significantly in the control group of SHRs (SBP 184 ± 14 to 152 ± 29 mmHg and DBP 149 ± 9 to 120 ± 14 mmHg, p < 0.05 for both) towards the end of the experiment but not in the SDR group. The RBC concentrations of ATP and GTP increased after exercise in both SDRs and SHRs which were significantly correlated with the postexercise hemodynamic effect (p < 0.05).

CONCLUSION

SHRs were more tolerant to increases in HR and SBP induced by exercise, and have more profound postexercise hemodynamic effects than SDRs. The hemodynamic effects were linked closely with RBC concentrations of ATP and GTP in both SDRs and SHRs.

Exercise training combined with electromyostimulation in the rehabilitation of patients with chronic heart failure: A randomized trial

AIM

Both aerobic training (AT) and electromyostimulation (EMS) of leg muscles improve exercise tolerance in patients suffering from chronic heart failure (CHF). It was speculated that combination of both methods might have an additive effect. This study was performed to evaluate the effects of a combination of AT and EMS in rehabilitation (RHB) of CHF patients.

PATIENTS AND METHODS

Patients (n=71; age 59 ± 10.2 yrs, NYHA II/III, EF 32 ± 7.1%) were randomized into 3 groups: a) group AT, b) group EMS, and c) group AT+EMS. AT protocol included standard activity on bicycle 3x a week at the level of individual anaerobic threshold. EMS (10 Hz, mode 20s "on"/20s "off") was applied to leg extensors for 2 h/day. Total time of given type of RHB was 12 weeks.

RESULTS

Data analysis revealed statistically significant improvements of patients in all experimental groups (averaged difference after 12 weeks of exercise as related to initial value: ∆VO2peak: +12.9%, ∆VO2AT: +9.3%, ∆Wpeak: +22.7%). No statistically significant difference among experimental groups was found. Quality of life (Minnesota Living with Heart Failure - MLHF) global score was significantly improved in all 3 groups: AT (∆MLHF: -27.9%; P=0.001), AT+EMS (∆MLHF: -29.1%; P=0.002), and EMS (∆MLHF: -16.6%; P=0.008). MLHF score in EMS group showed the smallest time-related improvement compared to AT and AT+EMS groups, and this difference in improvement between the groups was statistically significant (P=0.021).

CONCLUSION

No significant difference was found between the two types of exercise training.and nor did, their combination have any significant additional improvement.

Alterations in skeletal muscle indicators of mitochondrial structure and biogenesis in patients with type 2 diabetes and heart failure: effects of epicatechin rich cocoa

(-)-Epicatechin (Epi), a flavanol in cacao stimulates mitochondrial volume and cristae density and protein markers of skeletal muscle (SkM) mitochondrial biogenesis in mice. Type 2 diabetes mellitus (DM2) and heart failure (HF) are diseases associated with defects in SkM mitochondrial structure/function. A study was implemented to assess perturbations and to determine the effects of Epi-rich cocoa in SkM mitochondrial structure and mediators of biogenesis. Five patients with DM2 and stage II/III HF consumed dark chocolate and a beverage containing approximately 100 mg of Epi per day for 3 months. We assessed changes in protein and/or activity levels of oxidative phosphorylation proteins, porin, mitofilin, nNOS, nitric oxide, cGMP, SIRT1, PGC1α, Tfam, and mitochondria volume and cristae abundance by electron microscopy from SkM. Apparent major losses in normal mitochondria structure were observed before treatment. Epi-rich cocoa increased protein and/or activity of mediators of biogenesis and cristae abundance while not changing mitochondrial volume density. Epi-rich cocoa treatment improves SkM mitochondrial structure and in an orchestrated manner, increases molecular markers of mitochondrial biogenesis resulting in enhanced cristae density. Future controlled studies are warranted using Epi-rich cocoa (or pure Epi) to translate improved mitochondrial structure into enhanced cardiac and/or SkM muscle function.

Controlled study of myocardial recovery after interval training in heart failure: SMARTEX-HF--rationale and design

BACKGROUND

The large randomized controlled multicentre clinical trial, HF-ACTION, recently demonstrated that a programme of recommendation of regular exercise training at moderate intensity is safe, improves quality of life, and reduces the combined endpoint of all-cause death and hospitalization in patients with chronic heart failure. However, the size of beneficial effects was modest compared to results published in smaller single studies and meta-analyses.

OBJECTIVE

Based on results of a pilot study, the objective of the present investigation is to test the hypothesis that a programme comprising interval training at high relative intensity would yield significantly larger effects in terms of left ventricular remodelling compared to moderate continuous exercise training.

STUDY DESIGN

In a three-armed randomized multicentre study of stable heart failure patients with left ventricular ejection fraction ≤35%, the effects of a 12-week programme of high-intensity interval training (HIT; 85-90% of peak oxygen uptake, VO(2peak)) will be compared to actual practice in Europe, represented by either an isocaloric programme of moderate continuous training (MCT; 50-60% of VO(2peak)) and a recommendation of regular exercise (RE) of the individual patients' own preference based on clinical practice at the local centre. The primary endpoint is reverse remodelling, defined as change in left ventricular end-diastolic diameter assessed by echocardiography. Secondary endpoints include peak oxygen uptake (VO(2peak)), biomarkers, quality of life, and level of physical activity assessed by questionnaires. In addition, long-term maintenance of effects after the supervised training period will be determined. Assessments will be made at baseline, after the 12-week intervention programme, and at 1-year follow up. A total number of 200 patients on treatment per protocol, randomized to the three groups in a 1 : 1 : 1 manner, is estimated to detect clinically relevant differences in effect with HIT vs. MCT and RE (p < 0.05; statistical power 0.90) for the primary endpoint. Inclusion of patients started May 2009 and will run until total number has been reached.

End-of-life options for patients with advanced heart failure

Heart failure is a progressive disease with significant morbidity and mortality, but prognostication often is difficult. Many of the evidence-based therapies for heart failure provide symptomatic benefit, but may have intolerable side effects for patients with advanced disease. At the end of life, there is evidence of varying strengths for pharmacologic and nonpharmacologic relief of common symptoms like dyspnea, fatigue, pain, and depression. Patients also may benefit from inotropic therapy, ventricular assist devices, and hospice care. It is important for physicians to encourage patients to formulate advance directives, including decisions about do not resuscitate orders and deactivation of implantable cardioverter-defibrillators and ventricular assist devices.

Targeting stem cell niches and trafficking for cardiovascular therapy

Regenerative cardiovascular medicine is the frontline of 21st-century health care. Cell therapy trials using bone marrow progenitor cells documented that the approach is feasible, safe and potentially beneficial in patients with ischemic disease. However, cardiovascular prevention and rehabilitation strategies should aim to conserve the pristine healing capacity of a healthy organism as well as reactivate it under disease conditions. This requires an increased understanding of stem cell microenvironment and trafficking mechanisms. Engagement and disengagement of stem cells of the osteoblastic niche is a dynamic process, finely tuned to allow low amounts of cells move out of the bone marrow and into the circulation on a regular basis. The balance is altered under stress situations, like tissue injury or ischemia, leading to remarkably increased cell egression. Individual populations of circulating progenitor cells could give rise to mature tissue cells (e.g. endothelial cells or cardiomyocytes), while the majority may differentiate to leukocytes, affecting the environment of homing sites in a paracrine way, e.g. promoting endothelial survival, proliferation and function, as well as attenuating or enhancing inflammation. This review focuses on the dynamics of the stem cell niche in healthy and disease conditions and on therapeutic means to direct stem cell/progenitor cell mobilization and recruitment into improved tissue repair.