Exercise Intolerance in Patients With Heart Failure: JACC State-of-the-Art Review

Lean Mass Abnormalities in Heart Failure: The Role of Sarcopenia, Sarcopenic Obesity, and Cachexia

The role of body composition in patients with heart failure (HF) has been receiving much attention in the last few years. Particularly, reduced lean mass (LM), the best surrogate for skeletal muscle mass, is independently associated with abnormal cardiorespiratory fitness (CRF) and muscle strength, ultimately leading to reduced quality of life and worse prognosis. While in the past, reduced CRF in patients with HF was thought to result exclusively from cardiac dysfunction leading to reduced cardiac output at peak exercise, current evidence supports the concept that abnormalities in LM may also play a critical role. Abnormalities in the LM body composition compartment are associated with the development of sarcopenia, sarcopenic obesity, and cachexia. Such conditions have been implicated in the pathophysiology and progression of HF. However, identification of such conditions remains challenging, as universal definitions for sarcopenia, sarcopenic obesity, and cachexia are lacking. In this review article, we describe the most common body composition abnormalities related to the LM compartment, including skeletal and respiratory muscle mass abnormalities, and the consequences of such anomalies on CRF and muscle strength in patients with HF. Finally, we discuss the potential nonpharmacologic therapeutic strategies such as exercise training (ie, aerobic exercise and resistance exercise) and dietary interventions (ie, dietary supplementation and dietary patterns) that have been implemented to target body composition, with a focus on HF.

Shah K, Medina de Chazal H, Chiabrando JG, Vecchié A, Dell M, L. Mihalick V, Bogaev R, Hart L, Van Tassell BW, Arena R, Celi FS, Abbate A. The effects of canagliflozin compared to sitagliptin on cardiorespiratory fitness in type 2 diabetes mellitus and heart failure with reduced ejection fraction: The CANA-HF study

BACKGROUND

Canagliflozin reduces hospitalizations for heart failure (HF) in type 2 diabetes mellitus (T2DM). Its effect on cardiorespiratory fitness and cardiac function in patients with established HF with reduced ejection fraction (HFrEF) is unknown.

METHODS

We conducted a double-blind randomized controlled trial of canagliflozin 100 mg or sitagliptin 100 mg daily for 12 weeks in 88 patients, and measured peak oxygen consumption (VO₂ ) and minute ventilation/carbon dioxide production (VE/VCO₂ ) slope (co-primary endpoints for repeated measure ANOVA time_x_group interaction), lean peak VO₂ , ventilatory anaerobic threshold (VAT), cardiac function and quality of life (ie, Minnesota Living with Heart Failure Questionnaire [MLHFQ]), at baseline and 12-week follow-up.

RESULTS

The study was terminated early due to the new guidelines recommending canagliflozin over sitagliptin in HF: 17 patients were assigned to canagliflozin and 19 to sitagliptin, total of 36 patients. There were no significant changes in peak VO₂ and VE/VCO₂ slope between the two groups (P = .083 and P = .98, respectively). Canagliflozin improved lean peak VO₂ (+2.4 mL kg_LM^-1 min^-1 , P = .036), VAT (+1.5 mL kg^-1 min^-1 , P = .012) and VO₂ matched for respiratory exchange ratio (+2.4 mL Kg^-1 min^-1 , P = .002) compared to sitagliptin. Canagliflozin also reduced MLHFQ score (-12.1, P = .018).

CONCLUSIONS

In this small and short-term study of patients with T2DM and HFrEF, interrupted early after only 36 patients, canagliflozin did not improve the primary endpoints of peak VO₂ or VE/VCO₂ slope compared to sitagliptin, while showing favourable trends observed on several additional surrogate endpoints such as lean peak VO₂ , VAT and quality of life.

Mid-term survival of patients with chronic kidney disease after extracorporeal membrane oxygenation

OBJECTIVES

Chronic kidney disease (CKD) impairs the elimination of fluids, electrolytes and metabolic wastes, which can affect the outcomes of extracorporeal membrane oxygenation (ECMO) treatment. This study aimed to elucidate the impact of CKD on in-hospital mortality and mid-term survival of adult patients who received ECMO treatment.

METHODS

Patients who received first-time ECMO treatment between 1 January 2003 and 31 December 2013 were included. Those with CKD were identified and matched to patients without CKD using a 1:2 ratio and were followed for 3 years. The study outcomes included in-hospital outcomes and the 3-year mortality rate. A subgroup analysis was conducted by comparing the dialytic patients with the non-dialytic CKD patients.

RESULTS

The study comprised 1008 CKD patients and 2016 non-CKD patients after propensity score matching. The CKD patients had higher in-hospital mortality rates [69.5% vs 62.2%; adjusted odds ratio 1.41; 95% confidence interval (CI) 1.15-1.72] than the non-CKD patients. The 3-year mortality rate was 80.4% in the CKD group and 68% in the non-CKD group (adjusted hazard ratio 1.17; 95% CI 1.06-1.28). The subgroup analysis showed that the 3-year mortality rates were 84.5% and 78.4% in the dialytic and non-dialytic patients, respectively. No difference in the 3-year mortality rate was noted between the 2 CKD subgroups (P = 0.111).

CONCLUSIONS

CKD was associated with increased risks of in-hospital and mid-term mortalities in patients who received ECMO treatment. Furthermore, no difference in survival was observed between the patients with end-stage renal disease and non-dialytic CKD patients.

Current Studies and Future Directions of Exercise Therapy for Muscle Atrophy Induced by Heart Failure

Muscle atrophy is a common complication of heart failure. At present, there is no specific treatment to reverse the course of muscle atrophy. Exercise training, due to the safety and easy operation, is a recommended therapy for muscle atrophy induced by heart failure. However, the patients with muscle atrophy are weak in mobility and may not be able to train for a long time. Therefore, it is necessary to explore novel targets of exercise protection for muscle atrophy, so as to improve the quality of life and survival rate of patients with muscular atrophy induced by heart failure. This article aims to review latest studies, summarize the evidence and limitations, and provide a glimpse into the future of exercise for the treatment of muscle atrophy induced by heart failure. We wish to highlight some important findings about the essential roles of exercise sensors in muscle atrophy induced by heart failure, which might be helpful for searching potential therapeutic targets for muscle wasting induced by heart failure.

Left ventricular concentric remodeling and impaired cardiorespiratory fitness in patients with heart failure and preserved ejection fraction

BACKGROUND

Left ventricular (LV) concentric remodeling refers to a process by which increased LV relative wall thickness alters myocardial geometry, resulting in reduced LV end-diastolic volume (LVEDV) and stroke volume (SV). While the degree of concentric remodeling is a negative prognostic factor in heart failure with preserved ejection fraction (HFpEF), it is not known how it contributes to cardiorespiratory fitness (CRF).

METHODS

We performed a retrospective analysis of patients with HFpEF who underwent treadmill single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) and cardiopulmonary exercise testing (CPX). From exercise SPECT-MPI, we recorded postexercise LVEDVi, LVESVi, SVi, LVEF, the presence and extent of perfusion defects, and perfusion reversibility. Peak oxygen consumption (VO<inf>2</inf>), the oxygen uptake efficiency slope (OUES), oxygen (O<inf>2</inf>) pulse, ventilatory efficiency (V<inf>E</inf>/VCO<inf>2</inf> slope), ventilatory anaerobic threshold, respiratory exchange ratio, exercise time, and maximum heart rate were obtained from CPX. Data are expressed as mean (±standard deviation). Univariate and multivariate linear regression was performed.

RESULTS

We identified 23 subjects who had completed both an exercise SPECT-MPI and a CPX. Patients were more commonly women (83%), black (65%), middle age (50 [±7.3] years), and obese (Body Mass Index [BMI] 39.7 [±6.0] kg/m²). Greater LVEDVi and LVESVi correlated positively with peak VO<inf>2</inf> (R=+0.648, P=0.001; R=+0.601, P=0.002), O<inf>2</inf> pulse (R=+0.686, P<0.001; R=+0.625, P=0.001) and OUES (R=+0.882, P<0.001; R=+0.779, P<0.001). The LVEF correlated inversely with peak VO<inf>2</inf> and OUES (R=-0.450, P=0.031; R=-0.485, P=0.035). Perfusion defect area, grade of severity, and presence of reversibility were not associated with CRF variables.

CONCLUSIONS

Postexercise reduced LV volumes correlate with measures of impaired CRF in patients with HFpEF, thus supporting a pathophysiologic role of concentric remodeling in impaired CRF in HFpEF.

The association of dietary patterns and cardiorespiratory fitness: A systematic review

AIMS

In comparison to the traditional risk factors of cardiovascular diseases, little is known about the interaction between diet and cardiorespiratory fitness (CRF). The present systematic review aimed to provide comprehensive evidence regarding the relationship between the dietary patterns (DPs) with CRF in both children and adults.

DATA SYNTHESIS

Databases of PubMed, Scopus, and Web of Science were searched from inception up to December 2019. All observational studies that had extracted DPs using a posteriori and/or a priori methods, as well as had assessed CRF as the outcome, were eligible for inclusion in the review. Eleven studies (1 longitudinal and 10 cross-sectional studies) comprising a total of 198,271 subjects were included. There was considerable heterogeneity between studies in terms of the extracted DPs, their food items as well as the statistical reporting outcomes; which all made comparisons between the studies difficult. Despite some inconsistent results, overall there was a positive association between the DPs that were highly loaded with fruits and vegetables, as well as closer adherence to the high-quality diets particularly the Mediterranean diet, with higher values of CRF. While, an inverse association was found for unhealthy DPs that were generally characterized by a high intake of refined grains, sweets, meats, processed foods, and high-fat dairy products.

CONCLUSION

Overall, the evidence indicates the high-quality diets that are highlighted in the national dietary guidelines are associated with an optimal CRF. However, these findings should be confirmed by rigorous prospective and interventional studies.

Cardiopulmonary exercise testing - refining the clinical perspective by combining assessments

INTRODUCTION

Cardiorespiratory fitness (CRF) is now established as a vital sign. Cardiopulmonary exercise testing (CPX) is the gold-standard approach to assessing CRF.

AREAS COVERED

A body of literature spanning several decades clearly supports the clinical utility of CPX in those who are apparently health and at risk for chronic disease as well as numerous patient populations. While CPX, in and of itself, is a valid and reliable clinical assessment, combining findings with other available assessments may provide a more comprehensive perspective that enhances clinical decision making and outcomes. The current review will accomplish the following: (1) define key CPX measures based upon current evidence; and (2) describe the current evidence addressing the relationships between CPX and echocardiography, serum biomarkers, and cardiovascular magnetic resonance.

EXPERT OPINION

Cardiopulmonary exercise testing provides prognostic and diagnostic information in apparently healthy individuals, those at risk for one or more chronic conditions, as well as numerous patient populations. Moreover, if the goal of an intervention is to improve one or more systems integral to the physiologic response to exercise, CPX should be considered as a central assessment to gauge therapeutic efficacy. To further refine the information obtained from CPX, combining other assessments has demonstrated promise.

Prioritizing symptom management in the treatment of chronic heart failure

Chronic heart failure (CHF) is a chronic, progressive disease that has detrimental consequences on a patient's quality of life (QoL). In part due to requirements for market access and licensing, the assessment of current and future treatments focuses on reducing mortality and hospitalizations. Few drugs are available principally for their symptomatic effect despite the fact that most patients' symptoms persist or worsen over time and an acceptance that the survival gains of modern therapies are mitigated by poorly controlled symptoms. Additional contributors to the failure to focus on symptoms could be the result of under‐reporting of symptoms by patients and carers and a reliance on insensitive symptomatic categories in which patients frequently remain despite additional therapies. Hence, formal symptom assessment tools, such as questionnaires, can be useful prompts to encourage more fidelity and reproducibility in the assessment of symptoms. This scoping review explores for the first time the assessment options and management of common symptoms in CHF with a focus on patient‐reported outcome tools. The integration of patient‐reported outcomes for symptom assessment into the routine of a CHF clinic could improve the monitoring of disease progression and QoL, especially following changes in treatment or intervention with a targeted symptom approach expected to improve QoL and patient outcomes.

Impaired Exercise Tolerance in Heart Failure With Preserved Ejection Fraction: Quantification of Multiorgan System Reserve Capacity

Exercise intolerance is a principal feature of heart failure with preserved ejection fraction (HFpEF), whether or not there is evidence of congestion at rest. The degree of functional limitation observed in HFpEF is comparable to patients with advanced heart failure and reduced ejection fraction. Exercise intolerance in HFpEF is characterized by impairments in the physiological reserve capacity of multiple organ systems, but the relative cardiac and extracardiac deficits vary among individuals. Detailed measurements made during exercise are necessary to identify and rank-order the multiorgan system limitations in reserve capacity that culminate in exertional intolerance in a given person. We use a case-based approach to comprehensively review mechanisms of exercise intolerance and optimal approaches to evaluate exercise capacity in HFpEF. We also summarize recent and ongoing trials of novel devices, drugs, and behavioral interventions that aim to improve specific exercise measures such as peak oxygen uptake, 6-min walk distance, heart rate, and hemodynamic profiles in HFpEF. Evaluation during the clinically relevant physiological perturbation of exercise holds promise to improve the precision with which HFpEF is defined and therapeutically targeted.

Metabolic inflammation in heart failure with preserved ejection fraction

One in 10 persons in the world aged 40 years and older will develop the syndrome of HFpEF (heart failure with preserved ejection fraction), the most common form of chronic cardiovascular disease for which no effective therapies are currently available. Metabolic disturbance and inflammatory burden contribute importantly to HFpEF pathogenesis. The interplay within these two biological processes is complex; indeed, it is now becoming clear that the notion of metabolic inflammation-metainflammation-must be considered central to HFpEF pathophysiology. Inflammation and metabolism interact over the course of syndrome progression, and likely impact HFpEF treatment and prevention. Here, we discuss evidence in support of a causal, mechanistic role of metainflammation in shaping HFpEF, proposing a framework in which metabolic comorbidities profoundly impact cardiac metabolism and inflammatory pathways in the syndrome.

Redistribution of cardiac output during exercise by functional mitral regurgitation in heart failure: compensatory O2 peripheral uptake to delivery failure

This is an analysis involving 134 heart failure patients with reduced ejection fraction versus 80 controls investigated during functional evaluation with gas exchange and hemodynamic, addressing the severe mitral regurgitation phenotype and testing the hypothesis that the backward cardiac output redistribution to the lung during exercise impairs delivery and overexpresses peripheral extraction. This information is new and has important implications in the management of heart failure.

Exercise training reverses cardiac aging phenotypes associated with heart failure with preserved ejection fraction in male mice

Heart failure with preserved ejection fraction (HFpEF) is the most common type of HF in older adults. Although no pharmacological therapy has yet improved survival in HFpEF, exercise training (ExT) has emerged as the most effective intervention to improving functional outcomes in this age‐related disease. The molecular mechanisms by which ExT induces its beneficial effects in HFpEF, however, remain largely unknown. Given the strong association between aging and HFpEF, we hypothesized that ExT might reverse cardiac aging phenotypes that contribute to HFpEF pathophysiology and additionally provide a platform for novel mechanistic and therapeutic discovery. Here, we show that aged (24–30 months) C57BL/6 male mice recapitulate many of the hallmark features of HFpEF, including preserved left ventricular ejection fraction, subclinical systolic dysfunction, diastolic dysfunction, impaired cardiac reserves, exercise intolerance, and pathologic cardiac hypertrophy. Similar to older humans, ExT in old mice improved exercise capacity, diastolic function, and contractile reserves, while reducing pulmonary congestion. Interestingly, RNAseq of explanted hearts showed that ExT did not significantly modulate biological pathways targeted by conventional HF medications. However, it reversed multiple age‐related pathways, including the global downregulation of cell cycle pathways seen in aged hearts, which was associated with increased capillary density, but no effects on cardiac mass or fibrosis. Taken together, these data demonstrate that the aged C57BL/6 male mouse is a valuable model for studying the role of aging biology in HFpEF pathophysiology, and provide a molecular framework for how ExT potentially reverses cardiac aging phenotypes in HFpEF.

Outcome assessment using estimation of left ventricular filling pressure in asymptomatic patients at risk for heart failure with preserved ejection fraction

AIMS

High prevalence and lack of pharmacological treatment are making heart failure with preserved ejection fraction (HFpEF) a growing public health problem. No algorithm for the screening of asymptomatic patients with risk for HFpEF exists to date. We assessed whether HFA/ESC 2007 diagnostic criteria for HFpEF are helpful to investigate the cardiovascular outcome in asymptomatic patients.

METHODS AND RESULTS

We performed an analysis of the Diagnostic Trial on Prevalence and Clinical Course of Diastolic Dysfunction and Heart Failure (DIAST-CHF) that recruited patients with cardiovascular risk factors. All patients underwent a comprehensive diagnostic workup at baseline. Asymptomatic patients with preserved LVEF (>50%) were selected and classified according to HFA/ESC surrogate criteria for left ventricular elevated filling pressure (mean E/e' >15 or E/e' >8 and presence of either NT-proBNP > 220 ng/l, BNP > 200 ng/l or atrial fibrillation) into elevated filling pressure (FPe) or controls. Cardiovascular hospitalizations and all-cause death were assessed for both groups over a 10-year-follow-up.851 asymptomatic patients (age 65.5 ± 7.6 years, 44% female) were included in the analysis. FPe-patients were significantly older (p < 0.001), more often female (p = 0.003) and more often had a history of coronary artery disease, atrial fibrillation and renal dysfunction (p < 0.001, respectively) compared to controls. Incidence of death was significantly higher in the FPe group after a 10-year follow-up (p < 0.001), whereas cardiovascular hospitalization did not differ between groups.

CONCLUSION

Asymptomatic patients that fulfill HFA/ESC diagnostic criteria for HFpEF are at higher risk of symptomatic HFpEF and have a worse 10-year-outcome than those who do not fulfill criteria.

Therapeutic RNA Strategies for Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation with persistent respiratory symptoms. Current therapeutics for COPD are largely borrowed from the drug armamentarium for the treatment of asthma, which has different pathophysiological mechanisms from COPD. COPD has been linked to dysregulated expression of mRNAs and noncoding (nc)RNAs including miRNAs, PIWI-interacting (pi)RNAs, long noncoding (lnc)RNAs, and circular (circ)RNAs. This review highlights and discusses some recent advances towards development of RNA therapeutics for COPD.

Central role of left atrial dynamics in limiting exercise cardiac output increase and oxygen uptake in heart failure: insights by cardiopulmonary imaging

AIMS

In heart failure (HF), the haemodynamic response to exercise in relation to left atrial (LA) dynamics is unexplored. We sought to define whether abnormal LA dynamics during exercise may play a role in cardiac output (CO) limitation and tested its ability to predict outcome.

METHODS AND RESULTS

A total of 195 HF patients with reduced (n = 105), mid-range (n = 48), and preserved (n = 42) left ventricular ejection fraction (LVEF) and 46 non-cardiac dyspnoea (NCD) subjects underwent cardiopulmonary imaging with assessment of LA strain and strain rate (sra). HF patients, irrespective of LVEF, exhibited a significantly impaired LA strain and LA sra at rest, during exercise and recovery compared to NCD subjects with a blunted response in CO and right ventricular to pulmonary circulation coupling. LA strain and LA sra during exertion were significantly correlated with peak stroke volume index, peak CO and peak cardiac power output (R = 0.33, 0.48, 0.50 and R = 0.36, 0.51, 0.52 for LA strain and LA sra, respectively; all P < 0.001). In HF, after adjustment for age, gender, left atrial volume index, peak mitral regurgitation > 2, peak LVEF and peak heart rate, a higher LA strain (1% increase) during exercise was associated with a higher peak stroke volume index (mL/m² ), CO (L/min) and cardiac power output (mmHg L/min) at multivariable analyses (β-coefficients ± standard error = 0.23 ± 0.07, 0.046 ± 0.014 and 0.012 ± 0.004, respectively; P < 0.05). The same associations were found also for LA sra (absolute value) (1/s increase, β-coefficients ± standard error = 1.91 ± 0.68, 0.43 ± 0.14 and 0.12 ± 0.04, respectively; P < 0.05). Exercise LA strain (adjusted hazard ratio 0.94, 95% confidence interval 0.92-0.97, P < 0.001) and LA sra (adjusted hazard ratio 0.60, 95% confidence interval 0.43-0.84, P = 0.003) were associated with a worse outcome after adjusting for age and gender.

CONCLUSIONS

In HF, LA dynamics may play a key role in exercise CO increase due to an impaired forward (left ventricular filling) and backward (right ventricular to pulmonary circulation uncoupling) combination of mechanisms, irrespective of LVEF. The blunted LA strain and LA sra reserve during exercise are associated with a worse cardiopulmonary performance and outcome.

Cardiopulmonary exercise capacity and quality of life of patients with heart failure undergoing a functional training program: study protocol for a randomized clinical trial

BACKGROUND

Exercise intolerance is a common finding in heart failure that generates a vicious cycle in which the individual starts to limit his activities even more due to progressive fatigue. Regular physical exercise can increase the cardiopulmonary exercise capacity of these individuals. A new approach to physical exercise, known as functional training, could improve the oxygen consumption and quality of life of patients with heart failure; however, there is no information about the effect of this modality of exercise in this patient population. This randomized trial will compare the effects of 36 sessions of functional training versus strength training in heart failure patients.

METHODS

This randomized parallel-design examiner-blinded clinical trial includes individuals of both sexes aged ≥40 years receiving regular follow-up at a single academic hospital. Subjects will be randomly allocated to an intervention group (for 12-week functional training) or an active comparator group (for 12-week strength training). The primary outcomes will be the difference from baseline to the 3-month time point in peak oxygen consumption on cardiopulmonary exercise testing and quality of life assessed by the Minnesota Living with Heart Failure Questionnaire. Secondary outcome measures will include functionality assessed by the Duke Activity Status Index and gait speed test; peripheral and inspiratory muscular strength, assessed by hand grip and manovacuometry testing, respectively; endothelial function by brachial artery flow-mediated dilation; lean body mass by arm muscle circumference; and participant adherence to the exercise programs classified as a percentage of the prescribed exercise dose.

DISCUSSION

The functional training program aims to improve the functional capacity of the individual using exercises that relate to his specific physical activity transferring gains effectively to one's daily life. In this context, we believe that that functional training can increase the cardiopulmonary exercise capacity and quality of life of patients with heart failure. The trial has been recruiting patients since October 2017.

TRIAL REGISTRATION

NCT03321682. Registered on October 26, 2017.

Rationale and design for a multicenter, randomized, double-blind, placebo-controlled, phase 2 study evaluating the safety and efficacy of the soluble guanylate cyclase stimulator praliciguat over 12 weeks in patients with heart failure with preserved ejection fraction (CAPACITY HFpEF)

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a significant cause of morbidity and mortality worldwide. Exercise intolerance is the main symptom of HFpEF and is associated with a poor quality of life and increased mortality. Currently, there are no approved medications for the treatment of HFpEF. Praliciguat (IW-1973), a novel soluble guanylate cyclase stimulator that may help restore deficient nitric oxide-soluble guanylate cyclase-cyclic guanosine 3',5'-monophosphate signaling, is being investigated for the treatment of patients with HFpEF.

METHODS

CAPACITY HFpEF is a phase 2, multicenter, randomized, double-blind, placebo-controlled, parallel-group trial designed to evaluate the safety and efficacy of praliciguat over 12 weeks in approximately 184 patients with HFpEF. Eligible patients must have evidence supporting clinical HFpEF and at least 2 of the following 4 conditions associated with NO deficiency: diabetes/prediabetes, hypertension, obesity, and age >70 years. The primary efficacy end point is the change from baseline in peak VO₂ by cardiopulmonary exercise test (CPET). Secondary end points include the change from baseline in 6-minute walk test distance and the change in ventilatory efficiency on CPET, as well as number of CPET responders. Other exploratory end points include changes in echocardiographic parameters, New York Heart Association functional classification, cardiac events, blood and urine biomarkers pathophysiologically relevant to heart failure, and patient-reported outcomes including Kansas City Cardiomyopathy Questionnaire.

CONCLUSIONS

The CAPACITY HFpEF trial will provide data on short-term safety and efficacy of praliciguat on peak exercise capacity, as well as multiple secondary end points of submaximal functional capacity, patient-reported outcomes, and biomarkers.

Changes in Respiratory Muscle Strength Following Cardiac Rehabilitation for Prognosis in Patients with Heart Failure

Respiratory muscle weakness, frequently observed in patients with heart failure (HF), is reported as a predictor for poor prognosis. Although increased respiratory muscle strength ameliorates exercise tolerance and quality of life in HF patients, the relationship between changes in respiratory muscle strength and patient prognosis remains unclear. A total of 456 patients with HF who continued a 5-month cardiac rehabilitation (CR) were studied. We measured maximal inspiratory pressure (PI_max) at hospital discharge as the baseline and five months thereafter to assess the respiratory muscle strength. Changes in PI_max during the 5-month observation period (⊿PI_max) were examined. We investigated the composite multiple incidence of all-cause death or unplanned readmission after 5-month CR. The relationship between ⊿PI_max and the incidence of clinical events was analyzed. Over a median follow-up of 1.8 years, 221 deaths or readmissions occurred, and their rate of incidence was 4.3/100 person-years. The higher ⊿PI_max was significantly associated with lower incidence of clinical event. In multivariate Poisson regression model after adjustment for clinical confounding factors, ⊿PI_max remained a significant and independent predictor for all-cause death/readmission (adjusted incident rate ratio for ⊿PI_max increase of 10 cmH₂O: 0.77, 95% confidence interval: 0.70–0.86). In conclusion, the changes in respiratory muscle strength independently predict the incidence of clinical events in patients with HF.

Android to gynoid fat ratio and its association with functional capacity in male patients with heart failure

AIMS

We studied the association between android (A) to gynoid (G) fat ratio and functional capacity (peak VO₂ ) in male patients with heart failure with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

We enrolled 118 male patients with HFrEF with left ventricular ejection fraction (LVEF) <40%. Body composition (by using dual x-ray absorptiometry) and peak VO₂ (by cardiopulmonary exercise testing) were measured. Sarcopenic obesity was defined according to the Foundation for the National Institutes of Health criteria (FNIH). Blood sample for metabolic and hormonal parameters were measured. Fifteen patients (12.7%) showed sarcopenic obesity (body mass index > 25 kg/m² with FNIH index < 0.789). The median A/G ratio was 0.55. A/G ratio > 0.55 was detected in 60 patients. Relative peak VO₂ was lower in patients with A/G ratio > 0.55 than in patients with A/G ratio <0.55 (18.7 ± 5.3 vs. 22.5 ± 6.1 mL/kg/min, P < 0.001). Logistic regression analysis showed A/G ratio >0.55 to be independently associated with reduced peak VO₂ adjusted for age, body mass index, LVEF, presence of sarcopenia, anabolic hormones, and haemoglobin (odds ratio 3.895, 95% confidence interval 1.030-14.730, P = 0.045).

CONCLUSIONS

Body fat distribution, particularly android and gynoid fat composition, together with other cofactors, might have an important adverse role on functional capacity in male patients with HFrEF. Future studies are needed to address possible mechanisms involved in this relationship.

Determinants of Cardiorespiratory Fitness Following Thoracic Radiotherapy in Lung or Breast Cancer Survivors

We measured peak oxygen consumption (VO2) in previous recipients of thoracic radiotherapy and assessed the determinants of cardiorespiratory fitness with an emphasis on cardiac and pulmonary function. Cancer survivors who have received thoracic radiotherapy with incidental cardiac involvement often experience impaired cardiorespiratory fitness, as measured by reduced peak VO2, a marker of impaired cardiovascular reserve. We enrolled 25 subjects 1.8 (0.1 to 8.2) years following completion of thoracic radiotherapy with significant heart exposure (at least 10% of heart volume receiving at least 5 Gray). All subjects underwent cardiopulmonary exercise testing, Doppler echocardiography, and circulating biomarkers assessment. The cohort included 16 Caucasians (64%), 15 women (60%) with a median age of 63 (59 to 66) years. The peak VO2 was 16.8 (13.5 to 21.9) ml·kg-1·min-1 or moderately reduced at 62% (50% to 93%) of predicted. The mean cardiac radiation dose was 5.4 (3.7 to 14.7) Gray, and it significantly correlated inversely with peak VO2 (R = -0.445, p = 0.02). Multivariate regression analysis revealed the diastolic functional reserve index and the N-terminal pro-brain natriuretic peptide (NTproBNP) serum levels were independent predictors of peak VO2 (ß = +0.813, p <0.01 and ß = -0.414, p = 0.04, respectively). In conclusion, patients who had received thoracic radiation display a dose-dependent relation between the cardiac radiation dose received and the impairment in peak VO2, the reduction in diastolic functional reserve index, and elevation of NTproBNP.

Acute Decompensated Heart Failure in Patients with Heart Failure with Reduced Ejection Fraction

Acute decompensated heart failure (ADHF) requires immediate treatments because it impairs perfusion to systemic organs and their function. Half of all patients with ADHF are diagnosed with heart failure with reduced left ventricular ejection fraction (HFrEF). The initial goal of management for ADHF is to stabilize hemodynamic status. Pulmonary edema is treated with vasodilators or diuretics. Inhibitors of the renin-angiotensin-aldosterone system and β-blockers should be started and/or increased to meet the maximum dose, ideally the target dose, that the patient can tolerate as a treatment of HFrEF. Patients with severe circulatory failure need inotropic drugs or mechanical circulatory support.

Increased C-reactive protein is associated with the severity of thoracic radiotherapy-induced cardiomyopathy

BACKGROUND

Irradiation of the heart during cancer radiotherapy is associated with a dose-dependent risk of heart failure. Animal studies have demonstrated that irradiation leads to an inflammatory response within the heart as well as a reduction in cardiac reserve. In the current study we aimed to evaluate whether inflammatory biomarkers correlated with changes in cardiac function and reserve after radiotherapy for breast or lung cancer.

METHODS AND RESULTS

We studied 25 subjects with a history of breast or lung cancer without a prior diagnosis of cardiovascular disease or heart failure, 1.8 years [0.4-3.6] post-radiotherapy involving at least 5 Gray (Gy) to at least 10% of the heart. High-sensitivity C-reactive protein (CRP) was abnormal (≥2 mg/L) in 16 (64%) subjects. Cardiac function and reserve was measured with Doppler echocardiography before and after exercise and defined as left-ventricular ejection fraction (LVEF), early diastolic mitral annulus velocity (e'), and increase in LV outflow tract velocity time integral cardiac output (cardiac reserve) with exercise. Subjects with abnormal CRP had significantly lower LVEF (51 [44-59] % vs 61 [52-64] %, P = 0.039), lower e' (7.4 [6.6-7.9] cm/sec vs 9.9 [8.3-12.0] cm/sec, P = 0.010), and smaller cardiac reserve (+ 1.5 [1.2-1.7] L/min vs + 1.9 [1.7-2.2] L/min, P = 0.024).

CONCLUSION

Elevated systemic inflammation is associated with impaired left-ventricular systolic and diastolic function both at rest and during exercise in subjects who have received radiotherapy with significant incidental heart dose for the treatment of cancer.

Exercise intolerance in heart failure: The important role of pulmonary hypertension

NEW FINDINGS

What is the topic of this review? This review concerns the negative impact of pulmonary hypertension (PH) on the pulmonary haemodynamic and gas exchange responses to exercise, considering the mechanisms by which PH plays a role in exercise intolerance in heart failure (HF) patients. What advances does it highlight? The hallmark limited pulmonary vascular 'reserve' and impaired pulmonary gas exchange responses to exercise in HF are worsened by the development of PH; these are key determinants of exercise intolerance. Even HF patients who present with 'normal' pulmonary vascular function experience exercise-induced PH, which plays a role in exercise intolerance.

ABSTRACT

Patients with heart failure universally complain of exertional intolerance, but the underlying cause(s) of this intolerance may differ between patients with different disease phenotypes. Exercise introduces an impressive stress to the lungs, where elevations in venous return and cardiac output engender substantial increases in pulmonary blood volume and flow. Relative to healthy individuals, the pulmonary vascular reserve to accept this increase in pulmonary perfusion is compromised in heart failure, with a growing body of evidence suggesting that the development of pulmonary hypertension (PH), and in particular a precapillary component of PH, worsens the pulmonary haemodynamic response to exercise in these patients. Characterized by an exaggerated increase in pulmonary arterial pressure and an elevation in pulmonary vascular resistance, this dysfunctional pulmonary haemodynamic response plays a role in exercise intolerance, probably through an impairment of right ventricular function, underperfusion of the pulmonary circulation and a subsequent reduction in systemic blood flow and oxygen delivery. The hallmark abnormalities in ventilatory and pulmonary gas exchange that accompany heart failure, including a greater ventilatory equivalent for carbon dioxide, are also worsened by the development of PH. This raises the possibility that measures of exercise pulmonary gas exchange might help to 'describe' underlying PH in heart failure; however, several fundamental issues and questions need to be addressed before such gas exchange measures could truly be considered efficacious measures used to differentiate the type of PH and track the severity of PH in heart failure. exercise intolerance, heart failure, pulmonary gas exchange, pulmonary haemodynamics, pulmonary hypertension.

Effects of myocardial function and systemic circulation on regional coronary perfusion

Cardiac-coronary interaction and the effects of its pathophysiological variations on spatial heterogeneity of coronary perfusion and myocardial work are still poorly understood. This hypothesis-generating study predicts spatial heterogeneities in both regional cardiac work and perfusion that offer a new paradigm on the vulnerability of the subendocardium to ischemia, particularly at the apex. We propose a mathematical and computational modeling framework to simulate the interaction of left ventricular mechanics, systemic circulation, and coronary microcirculation. The computational simulations revealed that the relaxation rate of the myocardium has a significant effect whereas the contractility has a marginal effect on both the magnitude and transmural distribution of coronary perfusion. The ratio of subendocardial to subepicardial perfusion density (Q_endo/Q_epi) changed by -12 to +6% from a baseline value of 1.16 when myocardial contractility was varied by +25 and -10%, respectively; Q_endo/Q_epi changed by 37% when sarcomere relaxation rate, b, was faster and increased by 10% from the baseline value. The model predicts axial differences in regional myocardial work and perfusion density across the wall thickness. Regional myofiber work done at the apex is 30-50% lower than at the center region, whereas perfusion density in the apex is lower by only 18% compared with the center. There are large axial differences in coronary flow and myocardial work at the subendocardial locations, with the highest differences located at the apex region. A mismatch exists between perfusion density and regional work done at the subendocardium. This mismatch is speculated to be compensated by coronary autoregulation.NEW & NOTEWORTHY We present a model of left ventricle perfusion based on an anatomically realistic coronary tree structure that includes its interaction with the systemic circulation. Left ventricular relaxation rate has a significant effect on the regional distribution of coronary flow and myocardial work.

Exercise intolerance and fatigue in chronic heart failure: is there a role for group III/IV afferent feedback?

Exercise intolerance and early fatiguability are hallmark symptoms of chronic heart failure. While the malfunction of the heart is certainly the leading cause of chronic heart failure, the patho-physiological mechanisms of exercise intolerance in these patients are more complex, multifactorial and only partially understood. Some evidence points towards a potential role of an exaggerated afferent feedback from group III/IV muscle afferents in the genesis of these symptoms. Overactivity of feedback from these muscle afferents may cause exercise intolerance with a double action: by inducing cardiovascular dysregulation, by reducing motor output and by facilitating the development of central and peripheral fatigue during exercise. Importantly, physical inactivity appears to affect the progression of the syndrome negatively, while physical training can partially counteract this condition. In the present review, the role played by group III/IV afferent feedback in cardiovascular regulation during exercise and exercise-induced muscle fatigue of healthy people and their potential role in inducing exercise intolerance in chronic heart failure patients will be summarised.

Effect of Ivabradine on Left Ventricular Diastolic Function, Exercise Tolerance and Quality of Life in Patients With Heart Failure: A Systemic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Ivabradine is a heart rate-lowering drug that selectively inhibits the funny (If) current of the sinoatrial node. It is currently recommended in patients with heart failure (HF) with reduced ejection fraction (HFrEF) in sinus rhythm and a heart rate of ≥ 70 beats per minute (bpm) at rest. To investigate whether ivabradine has an effect on diastolic dysfunction, exercise tolerance and quality of life (QOL), we conducted a systemic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

We searched PubMed, EMBASE and Cochrane Central Register of Clinical Trials for studies on the effect of ivabradine on left ventricular (LV) diastolic dysfunction, exercise tolerance, QOL, readmission for worsening HF and mortality in both patients with HF with preserved ejection fraction (HFpEF) and HFrEF.

RESULTS

Thirteen RCTs with 881 patients met the inclusion criteria. According to the pooled analysis, for the HFpEF subgroup, treatment with ivabradine resulted in a decrease in early diastolic mitral inflow to late diastolic flow ratio (E/A) (standardized mean difference (SMD): -0.53; 95% confidence interval (CI): -0.99, -0.07; P < 0.000) and increase in peak oxygen uptake during exercise (VO2) (SMD: 0.05; 95% CI: -0.35, 0.45; P < 0.00; I2 = 95.1%). Similar effect was seen in the HFrEF subgroup with decrease in E/A ratio (SMD: -0.33; 95% CI: -0.59, -0.06; P < 0.000) and early diastolic mitral inflow to annular velocity ratio (E/e') (SMD: -1.01; 95% CI: -1.49, -0.54; P < 0.012). Ivabradine therapy increased peak VO2 and 6-min walk test (6MWT) in HFrEF patients (SMD: 0.83; 95% CI: 0.35, 1.32; P < 0.00; I2 = 97.5% and SMD: 1.11; 95% CI: 0.82, 1.41; P < 0.000, respectively). There was also significant reduction in Minnesota Living with Heart Failure Questionnaire (MLHFQ) score (SMD: -0.68; 95% CI: -0.91, -0.45; P < 0.000). However, there was no significant difference in readmission for worsening HF and all-cause mortality between ivabradine and control (risk ratio (RR): 1.44; 95% CI: 0.73, 2.16; P < 0.148 and RR: 0.76; 95% CI: 0.19, 1.33; P < 0.907, respectively).

CONCLUSIONS

Ivabradine therapy is associated with improved LV diastolic function, increases exercise tolerance and hence QOL, but it has no significant effect on readmission for worsening HF and all-cause mortality.

Determinants of Cardiorespiratory Fitness in Patients with Heart Failure Across a Wide Range of Ejection Fractions

Impaired cardiorespiratory fitness (CRF) in heart failure (HF) is influenced by a complex array of cardiac and extracardiac factors. The study aimed to identify clinical determinants of CRF measured as peak oxygen consumption (peak VO₂) in HF patients, and to determine a peak VO₂ prediction model using regression equations. Retrospective analysis of 200 HF patients who completed treadmill cardiopulmonary exercise testing and underwent Doppler echocardiography and/or biomarker analysis on the same day was performed. After univariate linear regression analysis, a multivariate peak VO₂ prediction model was developed using significant variables in a stepwise linear regression analysis. In subjects with repeated testing, Pearson's correlation was used to assess correlations between measured and predicted change in peak VO₂ (Δpeak VO₂) over time. Mean age was 57 years, with 55% being male. Stepwise linear regression was used to generate a weighted model for peak VO₂: 30.895 + (-0.112•age[years]) + (0.296•hemoglobin [g/dl]) + (-0.101•E/e'[unit change]) + (-0.202• body mass index [kg/m²]) + (-0.593• N-terminal pro-brain natriuretic peptide [log_N pg/ml])) + (-1.349•CRP [log mg/L]). Predicted peak VO₂ correlated strongly with measured peak VO₂ in HF with reduced ejection fraction and HF with preserved ejection fraction patients (r = +0.63, p <0.001; r = +0.64, p <0.001, respectively). Predicted Δpeak VO₂ correlated with measured Δpeak VO₂ (r = +0.23, p <0.001). In conclusion, in patients with HF across a wide range of left ventricular ejection fraction, age, systemic inflammation, oxygen carrying capacity, obesity, and elevated filling pressures are the strongest predictors of impaired CRF. The proposed CRF model allows prediction of peak VO₂ in HF patients and may be used to estimate peak VO₂ changes over time.

Sarcopenic Obesity in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a public health epidemic that is projected to double over the next two decades. Despite the high prevalence of HFpEF, there are currently no FDA approved therapies for health-related outcomes in this clinical syndrome making it one the greatest unmet needs in cardiovascular medicine. Aging and obesity are hallmarks of HFpEF and therefore there is a high incidence of sarcopenic obesity (SO) associated with this syndrome. The presence of SO in HFpEF patients is noteworthy as it is associated with co-morbidities, worsened cardiovascular health, hospitalizations, quality of life, and mortality. Furthermore, SO plays a central role in exercise intolerance, the most commonly reported clinical symptom of this condition. The aim of this review is to provide insights into the current knowledge pertaining to the contributing pathophysiological mechanisms and clinical outcomes associated with HFpEF-related SO. Current and prospective therapies to address SO in HFpEF, including lifestyle and pharmaceutical approaches, are discussed. The urgent need for future research aimed at better understanding the multifaceted physiological contributions to SO in HFpEF and implementing interventional strategies to specifically target SO is highlighted.

Targeting the DPP-4-GLP-1 pathway improves exercise tolerance in heart failure patients: a systematic review and meta-analysis

BACKGROUND

The most significant manifestation of heart failure is exercise intolerance. This systematic review and meta-analysis was performed to investigate whether dipeptidyl peptidase-4 (DPP-4) inhibitors or glucagon-like peptide 1 receptor agonists (GLP-1 RAs), widely used anti-diabetic drugs, could improve exercise tolerance in heart failure patients with or without type 2 diabetes mellitus.

METHODS

An electronic search of PubMed, EMBASE and the Cochrane Library was carried out through March 8th, 2019, for eligible trials. Only randomized controlled studies were included. The primary outcome was exercise tolerance [6-min walk test (6MWT) and peak O2 consumption], and the secondary outcomes included quality of life (QoL), adverse events (AEs) and all-cause death.

RESULT

After the literature was screened by two reviewers independently, four trials (659 patients) conducted with heart failure patients with or without type 2 diabetes met the eligibility criteria. The results suggested that targeting the DPP-4-GLP-1 pathway can improve exercise tolerance in heart failure patients [MD 24.88 (95% CI 5.45, 44.31), P = 0.01] without decreasing QoL [SMD -0.51 (95% CI -1.13, 0.10), P = 0.10]; additionally, targeting the DPP-4-GLP-1 pathway did not show signs of increasing the incidence of serious AEs or mortality.

CONCLUSION

Our results suggest that DPP-4 inhibitors or GLP-1 RAs improve exercise tolerance in heart failure patients. Although the use of these drugs for heart failure has not been approved by any organization, they may be a better choice for type 2 diabetes mellitus patients with heart failure. Furthermore, as this pathway contributes to the improvement of exercise tolerance, it may be worth further investigation in exercise-intolerant patients with other diseases.

Lifestyle Interventions with a Focus on Nutritional Strategies to Increase Cardiorespiratory Fitness in Chronic Obstructive Pulmonary Disease, Heart Failure, Obesity, Sarcopenia, and Frailty

Cardiorespiratory fitness (CRF) is an independent predictor for all-cause and disease-specific morbidity and mortality. CRF is a modifiable risk factor, and exercise training and increased physical activity, as well as targeted medical therapies, can improve CRF. Although nutrition is a modifiable risk factor for chronic noncommunicable diseases, little is known about the effect of dietary patterns and specific nutrients on modifying CRF. This review focuses specifically on trials that implemented dietary supplementation, modified dietary pattern, or enacted caloric restriction, with and without exercise training interventions, and subsequently measured the effect on peak oxygen consumption (VO₂) or surrogate measures of CRF and functional capacity. Populations selected for this review are those recognized to have a reduced CRF, such as chronic obstructive pulmonary disease, heart failure, obesity, sarcopenia, and frailty. We then summarize the state of existing knowledge and explore future directions of study in disease states recently recognized to have an abnormal CRF.

Microvascular Dysfunction in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is an increasingly studied entity accounting for 50% of all diagnosed heart failure and that has claimed its own dignity being markedly different from heart failure with reduced EF in terms of etiology and natural history (Graziani et al., 2018). Recently, a growing body of evidence points the finger toward microvascular dysfunction as the major determinant of the pathological cascade that justifies clinical manifestations (Crea et al., 2017). The high burden of comorbidities such as metabolic syndrome, hypertension, atrial fibrillation, chronic kidney disease, obstructive sleep apnea, and similar, could lead to a systemic inflammatory state that impacts the physiology of the endothelium and the perivascular environment, engaging complex molecular pathways that ultimately converge to myocardial fibrosis, stiffening, and dysfunction (Paulus and Tschope, 2013). These changes could even self-perpetrate with a positive feedback where hypoxia and locally released inflammatory cytokines trigger interstitial fibrosis and hypertrophy (Ohanyan et al., 2018). Identifying microvascular dysfunction both as the cause and the maintenance mechanism of this condition has opened the field to explore specific pharmacological targets like nitric oxide (NO) pathway, sarcomeric titin, transforming growth factor beta (TGF-β) pathway, immunomodulators or adenosine receptors, trying to tackle the endothelial impairment that lies in the background of this syndrome (Graziani et al., 2018;Lam et al., 2018). Yet, many questions remain, and the new data collected still lack a translation to improved treatment strategies. To further elaborate on this tangled and exponentially growing topic, we will review the evidence favoring a microvasculature-driven etiology of this condition, its clinical correlations, the proposed diagnostic workup, and the available/hypothesized therapeutic options to address microvascular dysfunction in the failing heart.

Time-efficient physical training for enhancing cardiovascular function in midlife and older adults: promise and current research gaps

Cardiovascular diseases (CVD) remain the leading cause of death in developed societies, and "midlife" (50-64 yr) and older (65+) men and women bear the great majority of the burden of CVD. Much of the increased risk of CVD in this population is attributable to CV dysfunction, including adverse changes in the structure and function of the heart, increased systolic blood pressure, and arterial dysfunction. The latter is characterized by increased arterial stiffness and vascular endothelial dysfunction. Conventional aerobic exercise training, as generally recommended in public health guidelines, is an effective strategy to preserve or improve CV function with aging. However, <40% of midlife and older adults meet aerobic exercise guidelines, due in part to time availability-related barriers. As such, there is a need to develop evidence-based time-efficient exercise interventions that promote adherence and optimize CV function in these groups. Two promising interventions that may meet these criteria are interval training and inspiratory muscle strength training (IMST). Limited research suggests these modes of training may improve CV function with time commitments of ≤60 min/wk. This review will summarize the current evidence for interval training and IMST to improve CV function in midlife/older adults and identify key research gaps and future directions.

Mitochondrial reactive oxygen species generation in blood cells is associated with disease severity and exercise intolerance in heart failure patients

Systemic oxidative stress plays a key role in the development of chronic heart failure (CHF). We tested the hypothesis that mitochondrial reactive oxygen species (ROS) generation in circulating peripheral blood mononuclear cells (PBMCs) contributes to CHF progression. A total of 31 patients who had a history of hospital admission due to worsening HF were enrolled and grouped as having either mild CHF defined as New York Heart Association (NYHA) functional class I-II or moderate-to-severe CHF defined as NYHA functional class III. ROS levels in PBMC mitochondria were significantly increased in CHF patients with NYHA functional class III compared to those with NYHA functional class I-II, accompanied by impaired mitochondrial respiratory capacity in PBMCs. ROS generation in PBMC mitochondria was positively correlated with urinary 8-hydroxydeoxyguanosine, a systemic oxidative stress marker, in CHF patients. Importantly, mitochondrial ROS generation in PBMCs was directly correlated with plasma levels of B-type natriuretic peptide, a biomarker for severity of HF, and inversely correlated with peak oxygen uptake, a parameter of exercise capacity, in CHF patients. The study showed that ROS generation in PBMC mitochondria was higher in patients with advanced CHF, and it was associated with disease severity and exercise intolerance in CHF patients.

Obesity, risk of diabetes and role of physical activity, exercise training and cardiorespiratory fitness

The epidemic of obesity contributes to the burden of type 2 diabetes mellitus (T2DM) in the United States and worldwide. Importantly, obesity is not only preventable but can be treated, particularly with lifestyle modifications to forestall T2DM in those with excess adiposity. The mechanisms linking obesity to T2DM are numerous and involve adipose tissue remodeling as a result of unhealthy behaviors, including unhealthy diet, reduced physical activity (PA) and exercise training (ET), and increased sedentary behaviors. Taken together, these factors markedly reduce cardiorespiratory fitness (CRF), one of the strongest predictors for cardiovascular outcomes and all-cause mortality in the general population, but also in those with T2DM. In this review we describe the mechanisms leading to adipose tissue remodeling resulting in obesity, as well as the mechanisms linking excess adiposity to insulin resistance and, in turn, T2DM. We then present the therapeutic strategies that can be implemented in obesity to prevent T2DM, with a brief discussion on weight loss, and greater emphasis on PA and ET. We finally present the evidence to support the beneficial effects of such strategies in patients with established T2DM and discuss the importance of achieving improvements in CRF in this population to potentially improve clinical outcomes.