The influence of training characteristics on the effect of exercise training in patients with coronary artery disease: Systematic review and meta-regression analysis

Are exercise prescriptions for patients with cardiovascular disease, made by physiotherapists, in agreement with European recommendations?

AIMS

Physiotherapists often treat patients with (elevated risk for) cardiovascular disease (CVD), and should thus be able to provide evidence-based exercise advice to these patients. This study, therefore, aims to examine whether exercise prescriptions by physiotherapists to patients with CVD are in accordance with European recommendations.

METHODS AND RESULTS

This prospective observational survey included forty-seven Belgian physiotherapists. The participants agreed to prescribe exercise intensity, frequency, session duration, program duration, and exercise type (endurance or strength training) for the same three patient cases. Exercise prescriptions were compared between physiotherapists and relations with their characteristics were studied. The agreement between physiotherapists' exercise prescriptions and those from European recommendations ('agreement score': based on a maximal score of 60/per case) was assessed. A wide inter-clinician variability was noticed for all exercise modalities, leading to a large variance for total peak-effort training minutes (from 461 up to 9000 over the three cases). The exercise frequency was prescribed fully out of range of the recommendations and the prescription of additional exercise modes was generally flawed. Exercise intensity and program duration were prescribed partially correct. The addition of strength exercises and session duration was prescribed correctly. This led to physiotherapist agreement scores of 25.3 ± 9.6, 23.2 ± 9.9, and 27.1 ± 10.6 (all out of 60), for cases one, two, and three, respectively. A greater agreement score was found in younger colleagues and those holding a Ph.D.

CONCLUSION

Exercise prescriptions for CVD patients vary widely among physiotherapists and often disagree with European recommendations.

REGISTRATION

ClinicalTrials.gov NCT05449652.

Exercise-based cardiac rehabilitation for patients with coronary heart disease: a systematic review and evidence mapping study

INTRODUCTION

Exercise-based cardiac rehabilitation (CR) plays a critical role in coronary heart disease (CHD) management. There is a heritage in the effect of exercise-based CR with different exercise programs or intervention settings. This study developed an evidence matrix that systematically assesses, organizes, and presents the available evidence regarding exercise-based CR in CHD management.

EVIDENCE ACQUISITION

A comprehensive literature search was conducted across six databases. Two reviewers screened the identified literature, extracted relevant data, and assessed the quality of the studies. An evidence-mapping framework was established to present the findings in a structured manner. Bubble charts were used to represent the included systematic reviews (SRs). The charts incorporated information, exercise prescriptions, outcome indicators, associated P values, research quality, and the number of original studies. A descriptive analysis summarized the types of CR, intervention settings, influential factors, and adverse events.

EVIDENCE SYNTHESIS

Sixty-two SRs were included in this analysis, focusing on six exercise types in addition to assessing major adverse cardiovascular events (MACE), cost and rehabilitation outcomes. The most commonly studied exercise types were unspecified (28 studies, 45.2%) and aerobic (11 studies, 17.7%) exercises. All-cause mortality was the most frequently reported MACE outcome (22 studies). Rehabilitation outcomes primarily centered around changes in cardiac function (135 outcomes from 39 SRs). Only 8 (12.9%) studies were rated as "high quality." No significant adverse events were observed in the intervention group. Despite some variations among the included studies, most SRs demonstrated the benefits of exercise in improving one or more MACE or rehabilitation outcomes among CHD patients.

CONCLUSIONS

The proportion of high-quality evidence remains relatively low. Limited evidence is available regarding the effectiveness of specific exercise types and specific populations, necessitating further evaluation.

Appropriate exercise prescription in primary and secondary prevention of cardiovascular disease: why this skill remains to be improved among clinicians and healthcare professionals. A call for action from the EXPERT Network†

In Europe alone, on a yearly basis, millions of people need an appropriate exercise prescription to prevent the occurrence or progression of cardiovascular disease (CVD). A general exercise recommendation can be provided to these individuals (at least 150 min of moderate-intensity endurance exercise, spread over 3-5 days/week, complemented by dynamic moderate-intensity resistance exercise 2 days/week). However, recent evidence shows that this one size does not fit all and that individual adjustments should be made according to the patient's underlying disease(s), risk profile, and individual needs, to maximize the clinical benefits of exercise. In this paper, we (i) argue that this general exercise prescription simply provided to all patients with CVD, or elevated risk for CVD, is insufficient for optimal CVD prevention, and (ii) show that clinicians and healthcare professionals perform heterogeneously when asked to adjust exercise characteristics (e.g. intensity, volume, and type) according to the patient's condition, thereby leading to suboptimal CVD risk factor control. Since exercise training is a class 1A intervention in the primary and secondary prevention of CVD, the awareness of the need to improve exercise prescription has to be raised among clinicians and healthcare professionals if optimized prevention of CVD is ambitioned.

'Super Rehab': can we achieve coronary artery disease regression? A feasibility study protocol

INTRODUCTION

Patients diagnosed with coronary artery disease (CAD) are currently treated with medications and lifestyle advice to reduce the likelihood of disease progression and risk of future major adverse cardiovascular events (MACE). Where obstructive disease is diagnosed, revascularisation may be considered to treat refractory symptoms. However, many patients with coexistent cardiovascular risk factors, particularly those with metabolic syndrome (MetS), remain at heightened risk of future MACE despite current management.Cardiac rehabilitation is offered to patients post-revascularisation, however, there is no definitive evidence demonstrating its benefit in a primary prevention setting. We propose that an intensive lifestyle intervention (Super Rehab, SR) incorporating high-intensity exercise, diet and behavioural change techniques may improve symptoms, outcomes, and enable CAD regression.This study aims to examine the feasibility of delivering a multicentre randomised controlled trial (RCT) testing SR for patients with CAD, in a primary prevention setting.

METHODS AND ANALYSIS

This is a multicentre randomised controlled feasibility study of SR versus usual care in patients with CAD. The study aims to recruit 50 participants aged 18-75 across two centres. Feasibility will be assessed against rates of recruitment, retention and, in the intervention arm, attendance and adherence to SR. Qualitative interviews will explore trial experiences of study participants and practitioners. Variance of change in CAD across both arms of the study (assessed with serial CT coronary angiography) will inform the design and power of a future, multi-centre RCT.

ETHICS AND DISSEMINATION

Ethics approval was granted by South West-Frenchay Research Ethics Committee (reference: 21/SW/0153, 18 January 2022). Study findings will be disseminated via presentations to relevant stakeholders, national and international conferences and open-access peer-reviewed research publications.

TRIAL REGISTRATION NUMBER

ISRCTN14603929.

An evaluation of the role of the exercise training dose for changes in exercise capacity following a standard cardiac rehabilitation program

BACKGROUND

To retrospectively characterize and compare the dose of exercise training (ET) within a large cohort of patients demonstrating different levels of improvement in exercise capacity following a cardiac rehabilitation (CR) program.

METHODS

A total of 2310 patients who completed a 12-week, center-based, guidelines-informed CR program between January 2018 and December 2019 were included in the analysis. Peak metabolic equivalents (MET_peak) were determined pre- and post-CR during which total duration (ET time) and intensity [percent of heart rate peak (%HR_peak)] of supervised ET were also obtained. Training responsiveness was quantified on the basis of changes in MET_peak from pre- to post-CR. A cluster analysis was performed to identity clusters demonstrating discrete levels of responsiveness (i.e., negative, low, moderate, high, and very-high). These were compared for several baseline and ET-derived variables which were also included in a multivariable linear regression model.

RESULTS

At pre-CR, baseline MET_peak was progressively lower with greater training responsiveness (F_(4,2305) = 44.2, P < 0.01, η²_p = 0.71). Likewise, average training duration (F_(4,2305) = 10.7 P < 0.01, η²_p = 0.02) and %HR_peak (F_(4,2305) = 25.1 P < 0.01, η²_p = 0.042) quantified during onsite ET sessions were progressively greater with greater training responsiveness. The multivariable linear regression model confirmed that baseline MET_peak, training duration and intensity during ET, BMI, and age (P < 0.001) were significant predictors of MET_peak post-CR.

CONCLUSIONS

Along with baseline MET_peak, delta BMI, and age, the dose of ET (i.e., training duration and intensity) predicts MET_peak at the conclusion of CR. A re-evaluation of current approaches for exercise intensity prescription is recommended to extend the benefits of completing CR to all patients.

Heart Rate Variability-Guided Training for Improving Mortality Predictors in Patients with Coronary Artery Disease

The objective of this research was to investigate whether heart rate variability (HRV)-guided training improves mortality predictors to a greater extent than predefined training in coronary artery disease patients. Twenty-one patients were randomly allocated to the HRV-guided training group (HRV-G) or the predefined training group (PRED-G). They measured their HRV at home daily and trained three times a week for six weeks. Resting heart rate, isolated vagal-related HRV indices (i.e., RMSSD, HF, and SD₁), weekly averaged RMSSD, heart rate recovery, and maximum oxygen uptake were assessed before and after the training period. There was a statistically significant difference (p = 0.034) in the change in weekly averaged RMSSD in favor of the HRV-G, while no differences were found in the remaining analyzed variables (p > 0.050). Regardless of the training prescription method, exercise training decreased resting heart rate (p = 0.001; -4.10 [95% CI = -6.37--1.82] beats per minute (bpm)), and increased heart rate recovery at 2 min (p = 0.010; 4.33 [95% CI = 1.15-7.52] bpm) and maximum oxygen uptake (p < 0.001; 3.04 [95% CI = 1.70-4.37] mL·kg^-1·min^-1). HRV-guided training is superior to predefined training in improving vagal-related HRV when methodological factors are accounted for.

Exercise Training and Interventions for Coronary Artery Disease

Coronary artery disease (CAD) may be considered a main cause of mortality and the prevalence of CAD is increasing nowadays, leading to high health costs in many countries. Despite the fact of the regression of the atherosclerotic plaque, the decrease in blood viscosity and the growth of collateral vessels have been proposed as improvements that CAD patients may obtain under exercise performance. Thus, the present narrative review aimed to carry out a brief specific analysis of the results achieved when performing endurance, strength or inspiratory muscle training. Exercise attenuates certain pathophysiological processes of this disease, such as endothelial dysfunction or the vulnerability of atherosclerotic plaques, and produces improvements in functional capacity and muscle strength, among others. Within the different exercise modalities, the most important parameter to be considered seems to be the total caloric expenditure, and not so much the modality itself. As such, in cardiac rehabilitation, when prescribing exercise, we should possibly focus on the modality that obtains more adherence in patients. To conclude, it must be highlighted that total caloric expenditure is not being taken into account when comparing interventions and this relevant information should be considered in future studies.

Exercise intensity assessment and prescription in cardiovascular rehabilitation and beyond: why and how: a position statement from the Secondary Prevention and Rehabilitation Section of the European Association of Preventive Cardiology

A proper determination of the exercise intensity is important for the rehabilitation of patients with cardiovascular disease (CVD) since it affects the effectiveness and medical safety of exercise training. In 2013, the European Association of Preventive Cardiology (EAPC), together with the American Association of Cardiovascular and Pulmonary Rehabilitation and the Canadian Association of Cardiac Rehabilitation, published a position statement on aerobic exercise intensity assessment and prescription in cardiovascular rehabilitation (CR). Since this publication, many subsequent papers were published concerning the determination of the exercise intensity in CR, in which some controversies were revealed and some of the commonly applied concepts were further refined. Moreover, how to determine the exercise intensity during resistance training was not covered in this position paper. In light of these new findings, an update on how to determine the exercise intensity for patients with CVD is mandatory, both for aerobic and resistance exercises. In this EAPC position paper, it will be explained in detail which objective and subjective methods for CR exercise intensity determination exist for aerobic and resistance training, together with their (dis)advantages and practical applications.

Concurrent exercise does not prevent recognition memory deficits induced by beta-amyloid in rats

Alzheimer's disease affects thousands of people worldwide. Alternatives aiming to prevent the disease or reduce its symptoms include different physical exercise configurations. Here we investigate the potential of concurrent exercise to prevent recognition memory deficits in an Alzheimer's disease-like model induced by the hippocampal beta-amyloid (Aβ) injection in Wistar rats. We demonstrate that the concurrent exercise, which included running and strength exercises performed in the same exercise session, is ineffective in preventing recognition memory deficits in the Aβ rats. Besides, higher levels of reactive oxygen species were found in the concurrent exercise group's hippocampus. The running exercise administrated alone prevented recognition memory impairments.

The Effects Of Exercise Training On Physical, Physiological And Psychological Risk Factors Of Patients With Cardiovascular Disease

Background — Exercise training is an important component of wellness for individuals diagnosed with cardiovascular disease (CVD). Exercise may have an effect on cardiovascular risk factors such as hypertension, lipid levels, and other associated physical, psychological, and physiological risk factors. Exercise intensity may further impact those risk factors. Aim — This narrative review of the literature aims to identify the effect of regular physical exercise on modifying risk factors for CVD and increased morbidity and mortality related to CVD. Methods — Published English-language papers from 2011 to 2020, available in Scopus, PubMed, Cochrane, Google Scholar, and Thompson were included in this review. Keywords for this search were exercise training, cardiovascular disease, hypertension, physical function, physiological, and psychological risk factors. Conclusions — Exercise training may be a cost-effective intervention that improves the physical, physiological, and psychological risk factors and the motor function of patients with cardiovascular disease.

Multicomponent Training Prevents Memory Deficit Related to Amyloid-β Protein-Induced Neurotoxicity

BACKGROUND

Alzheimer's disease (AD) is characterized by the accumulation of the amyloid-β peptide in the brain, leading to early oxidative stress and neurotoxicity. It has been suggested that physical exercise could be beneficial in preventing AD, but studies with multicomponent training are scanty.

OBJECTIVE

Verify the effects of multicomponent exercise training to prevent deficits in recognition memory related to Aβ neurotoxicity.

METHODS

We subjected Wistar rats to multicomponent training (including aerobic and anaerobic physical exercise and cognitive exercise) and then infused amyloid-β peptide into their hippocampus.

RESULTS

We show that long-term multicomponent training prevents the amyloid-β-associated neurotoxicity in the hippocampus. It reduces hippocampal lipid peroxidation, restores antioxidant capacity, and increases glutathione levels, finally preventing recognition memory deficits.

CONCLUSION

Multicomponent training avoids memory deficits related to amyloid-β neurotoxicity on an animal model.

Evaluating Exercise Progression in an Australian Cardiac Rehabilitation Program: Should Cardiac Intervention, Age, or Physical Capacity Be Considered?

Progression of prescribed exercise is important to facilitate attainment of optimal physical capacity during cardiac rehabilitation. However, it is not clear how often exercise is progressed or to what extent. This study evaluated whether exercise progression during clinical cardiac rehabilitation was different between cardiovascular treatment, age, or initial physical capacity. The prescribed exercise of sixty patients who completed 12 sessions of outpatient cardiac rehabilitation at a major Australian metropolitan hospital was evaluated. The prescribed aerobic exercise dose was progressed using intensity rather than duration, while repetitions and weight lifted were utilised to progress resistance training dose. Cardiovascular treatment or age did not influence exercise progression, while initial physical capacity and strength did. Aerobic exercise intensity relative to initial physical capacity was progressed from the first session to the last session for those with high (from mean (95%CI) 44.6% (42.2-47.0) to 68.3% (63.5-73.1); p < 0.001) and moderate physical capacity at admission (from 53.0% (50.7-55.3) to 76.3% (71.2-81.4); p < 0.001), but not in those with low physical capacity (from 67.3% (63.7-70.9) to 85.0% (73.7-96.2); p = 0.336). The initial prescription for those with low physical capacity was proportionately higher than for those with high capacity (p < 0.001). Exercise testing should be recommended in guidelines to facilitate appropriate exercise prescription and progression.

Are the Current Cardiac Rehabilitation Programs Optimized to Improve Cardiorespiratory Fitness in Patients? A Meta-Analysis

Previous meta-analyses have shown that high-intensity interval training (HIIT) is more suitable than moderate continuous training (MCT) for improving peak oxygen uptake (VO2peak) in patients with coronary artery disease. However, none of these meta-analyses have tried to explain the heterogeneity of the empirical studies in optimizing cardiac rehabilitation programs. Therefore, our aims were (a) to estimate the effect of MCT and HIIT on VO2peak, and (b) to find the potential moderator variables. A search was conducted in PubMed, Scopus, and ScienceDirect. Out of the 3,110 references retrieved, 29 studies fulfilled the selection criteria to be included in our meta-analysis. The mean difference was used as the effect size index. Our results showed significant enhancements in VO2peak after cardiac rehabilitation based on MCT and HIIT (mean difference = 3.23; 95% confidence interval [2.81, 3.65] ml·kg-1·min-1 and mean difference = 4.61; 95% confidence interval [4.02, 5.19] ml·kg-1·min-1, respectively), with greater increases after HIIT (p < .001). Heterogeneity analyses reached statistical significance with moderate heterogeneity for MCT (p < .001; I2 = 67.0%), whereas no heterogeneity was found for the effect of HIIT (p = .220; I2 = 22.0%). Subgroup analyses showed significant between-group heterogeneity of the MCT-induced effect based on the training mode (p < .001; I2 = 90.4%), the risk of a new event (p = .010; I2 = 77.4%), the type of cardiovascular event (p = .009; I2 = 84.8%), the wait time to start cardiac rehabilitation (p = .010; I2 = 76.6%), and participant allocation (p = .002; I2 = 89.9%). Meta-regressions revealed that the percentages of patients undergoing a revascularization procedure (B = -0.022; p = .041) and cardiorespiratory fitness at baseline (B = -0.103; p = .025) were inversely related to the MCT-induced effect on the VO2peak.

[Blood flow restriction training for people with cardiovascular disease: An exploratory review]

OBJECTIVE

To analyse the evidence on the effects of blood flow restriction training in people with cardiovascular disease.

MATERIALS AND METHODS

We searched MEDLINE, EMBASE, SPORTDiscus, CINAHL, LILACS, SCOPUS and Wiley databases. Experimental and non-experimental studies investigating the effects of blood flow restriction in participants with cardiovascular disease were included.

RESULTS

Six clinical trials and three non-experimental studies met the inclusion criteria. The experimental studies were conducted in participants with hypertension and ischaemic heart disease. Non-experimental studies described hemodynamic adaptations and potential adverse effects of therapy. The risk of bias of the included clinical trials was moderate to high. Exercise-induced hemodynamic stress increased significantly during training with blood flow restriction compared with traditional training. The small number of available studies have focused mostly on acute effects, but chronic effects are unknown.

CONCLUSION

There is currently no evidence to recommend the use of blood flow restriction in people with cardiovascular disease.

Changes in Aerobic Capacity Over Time in Elderly Patients With Acute Myocardial Infarction During Cardiac Rehabilitation

OBJECTIVE

To test the hypothesis that a longer duration of phase II cardiac rehabilitation is required to recover the exercise capacity of elderly patients compared to younger patients.

METHODS

We retrospectively reviewed and analyzed the medical records of patients who were referred to our cardiac rehabilitation (CR) center and underwent percutaneous coronary intervention for acute myocardial infarction (AMI). A total of 70 patients were enrolled who underwent an exercise tolerance test (ETT) 3 weeks after the occurrence of an AMI (T0), 6 weeks after the first ETT (T1), and 12 weeks after the first ETT (T2). Patients older than 65 years were assigned to the elderly group (n=24) and those aged 65 years and younger to the younger group (n=46). Both groups performed center-based or home-based CR for 12 weeks (3 times per week and 1 session per day). Exercise intensity for each individual was based on the target heart rate calculated by the Karvonen formula. The change in maximal metabolic equivalents (METmax) of the two groups was measured at each assessment point (T0, T1, and T2) to investigate the recovery of exercise capacity.

RESULTS

The younger group showed improvement in METmax between T0 and T1. However, METmax of the elderly group showed no significant improvement between T0 and T1. The exercise capacity, measured with METmax, of all groups showed improvement between T0 and T2.

CONCLUSION

Elderly patients with AMI need a longer duration of CR (>6 weeks) than younger patients with AMI.

Cardiac rehabilitation of elderly patients in eight rehabilitation units in western Europe: Outcome data from the EU-CaRE multi-centre observational study

Aims

The European Cardiac Rehabilitation in the Elderly (EU-CaRE) HORIZON 2020 project compares the sustainable effects of cardiac rehabilitation (CR) in elderly patients.

Methods and results

A total of 1633 patients with coronary artery disease (CAD) or heart valve replacement (HVR), with or without revascularization, aged 65 or above, who participated in CR were included. Peak oxygen uptake (VO2peak), smoking, body mass index, diet, physical activity, serum lipids, psychological distress and medication were assessed before and after CR (T0 and T1) and after 12 months (T2). Patients undergoing coronary artery bypass surgery or surgical HVR had lower VO2peak at T0 and a greater increase to T1 and T2 (2.8 and 4.4 ml/kg/min, respectively) than CAD patients undergoing percutaneous or no revascularization (1.6 and 1.4 ml/kg/min, respectively). After multivariable adjustment, earlier CR uptake was associated with greater improvements in VO2peak. The proportion of CAD patients with three or more uncontrolled risk factors declined from 58.4% at T0 to 40.1% at T2 ( p < 0.0001). Psychological distress scores all improved and adherence to medication was overall good at all sites. There were significant differences in risk factor burden across sites, but no CR program was superior to others.

Conclusions

The outcomes of VO2peak in CR programs across Europe seemed mainly determined by timing of uptake and were maintained or even further improved at 1-year follow-up. Despite significant improvements, 40.1% of CAD patients still had three or more risk factors not at target after 1 year. Differences across sites could not be ascribed to characteristics of the CR programs offered.

Towards a personalised approach in exercise-based cardiovascular rehabilitation: How can translational research help? A 'call to action' from the Section on Secondary Prevention and Cardiac Rehabilitation of the European Association of Preventive Cardiology

The benefit of regular physical activity and exercise training for the prevention of cardiovascular and metabolic diseases is undisputed. Many molecular mechanisms mediating exercise effects have been deciphered. Personalised exercise prescription can help patients in achieving their individual greatest benefit from an exercise-based cardiovascular rehabilitation programme. Yet, we still struggle to provide truly personalised exercise prescriptions to our patients. In this position paper, we address novel basic and translational research concepts that can help us understand the principles underlying the inter-individual differences in the response to exercise, and identify early on who would most likely benefit from which exercise intervention. This includes hereditary, non-hereditary and sex-specific concepts. Recent insights have helped us to take on a more holistic view, integrating exercise-mediated molecular mechanisms with those influenced by metabolism and immunity. Unfortunately, while the outline is recognisable, many details are still lacking to turn the understanding of a concept into a roadmap ready to be used in clinical routine. This position paper therefore also investigates perspectives on how the advent of 'big data' and the use of animal models could help unravel inter-individual responses to exercise parameters and thus influence hypothesis-building for translational research in exercise-based cardiovascular rehabilitation.

A systematic review of recent cardiac rehabilitation meta-analyses in patients with coronary heart disease or heart failure

Aim: The aim of the project was to conduct a systematic review of meta-analyses of supervised, home-based or telemedicine-based exercise cardiac rehabilitation (CR) published between July 2011 and April 2018. Materials & methods: Evidence on mortality, hospitalization, peak VO₂, exercise capacity, muscle strength and health-related quality of life in patients with coronary heart disease or heart failure referred to CR was obtained by searching six electronic databases. Results: Of the 127 point estimates identified in the 30 CR meta-analyses identified (mortality, n = 12; hospitalization, n = 11; VO₂, n = 40; exercise capacity, n = 20; strength, n = 18; health-related quality of life, n = 26), 60% were statistically significant and 35% clinically important. Conclusion: The statistical data are sufficiently robust to promote strategies to improve referral to and participation in CR although evidence for clinical importance needs to be further investigated.

Accuracy of wearable heart rate monitors in cardiac rehabilitation

Background

To assess the accuracy of four wearable heart rate (HR) monitors in patients with established cardiovascular disease enrolled in phase II or III cardiac rehabilitation (CR).

Methods

Eighty adult patients enrolled in phase II or III CR were monitored during a CR session that included exercise on a treadmill and/or stationary cycle. Participants underwent HR monitoring with standard ECG limb leads, an electrocardiographic (ECG) chest strap monitor (Polar H7), and two randomly assigned wrist-worn HR monitors (Apple Watch, Fitbit Blaze, Garmin Forerunner 235, TomTom Spark Cardio), one on each wrist. HR was recorded at rest and at 3, 5, and 7 minutes of steady-state exercise on the treadmill and stationary cycle.

Results

Across all exercise conditions, the chest strap monitor (Polar H7) had the best agreement with ECG (r_c=0.99) followed by the Apple Watch (r_c=0.80), Fitbit Blaze (r_c=0.78), TomTom Spark (r_c=0.76) and Garmin Forerunner (r_c=0.52). There was variability in accuracy under different exercise conditions. On the treadmill, only the Fitbit Blaze performed well (r_c=0.76), while on the stationary cycle, Apple Watch (r_c=0.89) and TomTom Spark (r_c=0.85) were most accurate.

Conclusions

In cardiac patients, the accuracy of wearable, optically based HR monitors varies, and none of those tested was as accurate as an electrode-containing chest monitor. This observation has implications for in-home CR, as electrode-containing chest monitors should be used when accurate HR measurement is imperative.

Comparative Effectiveness of the Core Components of Cardiac Rehabilitation on Mortality and Morbidity: A Systematic Review and Network Meta-Analysis

A systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) evaluating the core components of cardiac rehabilitation (CR), nutritional counseling (NC), risk factor modification (RFM), psychosocial management (PM), patient education (PE), and exercise training (ET)) was undertaken. Published RCTs were identified from database inception dates to April 2017, and risk of bias assessed using Cochrane's tool. Endpoints included mortality (all-cause and cardiovascular (CV)) and morbidity (fatal and non-fatal myocardial infarction (MI), coronary artery bypass surgery (CABG), percutaneous coronary intervention (PCI), and hospitalization (all-cause and CV)). Meta-regression models decomposed treatment effects into the main effects of core components, and two-way or all-way interactions between them. Ultimately, 148 RCTs (50,965 participants) were included. Main effects models were best fitting for mortality (e.g., for all-cause, specifically PM (hazard ratio HR = 0.68, 95% credible interval CrI = 0.54⁻0.85) and ET (HR = 0.75, 95% CrI = 0.60⁻0.92) components effective), MI (e.g., for all-cause, specifically PM (hazard ratio HR = 0.76, 95% credible interval CrI = 0.57⁻0.99), ET (HR = 0.75, 95% CrI = 0.56⁻0.99) and PE (HR = 0.68, 95% CrI = 0.47⁻0.99) components effective) and hospitalization (e.g., all-cause, PM (HR = 0.76, 95% CrI = 0.58⁻0.96) effective). For revascularization (including CABG and PCI individually), the full interaction model was best-fitting. Given that each component, individual or in combination, was associated with mortality and/or morbidity, recommendations for comprehensive CR are warranted.

High intensity interval training versus moderate intensity continuous training on exercise capacity and quality of life in patients with heart failure with reduced ejection fraction: A systematic review and meta-analysis

OBJECTIVE

The aim of this study was to investigate the effects of high intensity interval training (HIIT) versus moderate intensity continuous training (MICT) in heart failure patients with reduced ejection fraction (HFrEF).

BACKGROUND

Despite the well-known positive effects of exercise in heart failure patients, the best mode of exercise is still under discussion.

METHODS

We searched Pubmed/MEDLINE, Cochrane Central Register of Controlled Trials, PEDro data base, and SciELO (from the earliest date available to October 2017) for randomized controlled trials that evaluated the effects of HIIT versus MICT in HFrEF patients. Weighted mean differences (WMD) with 95% confidence interval (CI) were calculated, and heterogeneity was assessed using the I² test.

RESULTS

13 studies met the study criteria, including 411 patients. Compared to MICT, HIIT resulted in improvement in Peak VO₂ WMD (1.35 mL·kg^-1·min^-1 95% CI: 0.03 to 2.64 N = 411). HIIT resulted in no difference in VE/VCO₂ slope WMD (-1.21 95% CI: -3.0 to 0.58 N = 135), and quality of life measured by Minnesota Living with Heart Failure questionnaire WMD (1.19 95% CI: -5.81 to 8.19 N = 79). Sub-group analyses comparing studies with and without isocaloric exercise training protocol also showed a nonsignificant difference in peak VO₂ for participants in the HIIT group compared with MICT group.

CONCLUSIONS

HIIT improves peak VO₂ and should be considered as a component of care of HFrEF patients. However, its superiority versus MICT disappears when isocaloric protocols are compared. An important caveat is uncertainty and variation of actual training intensities compared to program targets.