Aerobic Interval Training Elicits Different Hemodynamic Adaptations Between Heart Failure Patients with Preserved and Reduced Ejection Fraction

Insights Into the Role of Obesity in Heart Failure With Preserved Ejection Fraction Pathophysiology and Management

Heart failure (HF) is a significant global health issue, categorized by left ventricular ejection fraction, being either reduced (HFrEF < 0.40) or preserved (HFpEF > 0.50), or in the middle of this range. Although the overall incidence of HF remains stable, HFpEF cases are increasing, representing about 50% of all HF cases. Outcomes for HFpEF are similar to those for HFrEF, leading to substantial health-care resource use. Despite extensive research over the past 2 decades, the prognosis and mortality rates for HFpEF remain high. A key feature of HFpEF is exercise intolerance, characterized by severe exertional dyspnea and fatigue, which significantly impacts quality of life. The underlying mechanisms of exercise intolerance are not fully understood due to the complex pathophysiology and multisystem involvement. Obesity is a common comorbidity in HFpEF, especially in North America, leading to worsening symptoms, hemodynamics, and mortality rates. Increased adiposity leads to inflammation, hypertension, dyslipidemia, and insulin resistance, and impairing cardiac, vascular, pulmonary, and skeletal muscle function. Therefore, managing obesity is crucial in treating HFpEF. In this review we explore the pathophysiologic mechanisms of HFpEF, emphasizing obesity's role, and we discuss current management strategies while identifying areas needing further research.

Training-induced change of diastolic function in heart failure with preserved ejection fraction

AIMS

Exercise training improves aerobic capacity (V̇O2peak) in patients with heart failure and preserved ejection fraction (HFpEF), but underlying mechanisms remain unclear. We aimed to evaluate whether exercise training could improve systolic and diastolic function during exercise.

METHODS

This was a substudy of the multicentre Optimizing Exercise Training in HFpEF (OptimEx-Clin) trial, in which 180 patients with HFpEF were randomized 1:1:1 to guideline control, moderate continuous training or high-intensity interval training. All patients included at two out of five participating sites underwent exercise echocardiography at baseline and 3 months. Patients of both training groups were pooled and compared with guideline control.

RESULTS

A total of 61 patients (mean age 73 ± 7 years, 72% female) were included. At baseline, E/e' increased from 17.0 ± 5.7 to 19.5 ± 6.1 and systolic pulmonary artery pressure from 31 ± 8 to 51 ± 11 mmHg (both P < 0.001). Right ventricular function did not change significantly (maximal tricuspid annular plane systolic excursion 24.7 ± 4.0 mm, P = 0.051 vs. baseline). At 3 months, patients randomized to exercise training improved V̇O2peak (control +0.2, training +2.7 mL/kg/min, P = 0.006) and demonstrated small but significant improvements in exercise E/e' (control 21.7 ± 7.5 to 22.8 ± 9.2, training 18.3 ± 5.0 to 17.2 ± 4.1, P = 0.044). No significant changes were observed in ejection fraction, mitral or tricuspid annular plane systolic excursion, S', A' or systolic pulmonary artery pressure (P > 0.05). Changes in E/e' were not associated with the change in V̇O2peak.

CONCLUSIONS

In patients with HFpEF, exercise echocardiography revealed increases in filling pressures as well as a failure to augment right ventricular function during exercise. After 3 months of exercise training, HFpEF patients demonstrated a small improvement in diastolic function (exercise E/e'), but this did not explain the improved aerobic capacity.

Determinants of Longitudinal Changes in Exercise Capacity in Patients With Independent Functioning on Hemodialysis

OBJECTIVE

Patients with chronic kidney disease reportedly have decreased muscle oxygen utilization, which most substantially decreases exercise capacity, followed by cardiac reserve. However, determinants of longitudinal changes in exercise capacity in patients on hemodialysis (HD) and the effects of long-term exercise interventions (EI) are unknown. This study was conducted to clarify these concerns.

METHODS

This was a prospective cohort study. Patients on HD that were not hospitalized were followed from baseline up to 2 years, and cardiopulmonary exercise testing results, including peak oxygen uptake, peak work rate, heart rate reserve, and ventilatory equivalent for carbon dioxide slope, as well as implementation of EI were assessed. Based on the 2-year change in peak oxygen uptake, they were divided into improvement or declined groups.

RESULTS

Forty-five patients who were not hospitalized completed the follow-up were analyzed. In the improvement group, the variation was determined by an increase in peak work rate, which is a peripheral factor (partial regression coefficient 0.08 [95% CI = 0.01 to 0.16]), while in the decline group, the variation was determined by a decrease in the ventilatory equivalent for carbon dioxide slope, which is a cardiac factor (partial regression coefficient = -0.12; 95% CI = -0.21 to -0.03). Moreover, exercise intervention was associated with the change in peak oxygen uptake (partial regression coefficient = 3.09; 95% CI = 1.45 to 4.72).

CONCLUSION

Exercise intolerance even in patients on HD that were not hospitalized and stable progressed over time with deterioration of cardiac reserve, whereas EI were associated with improved exercise capacity through enhanced peripheral function.

IMPACT

The results support the early measurement of cardiopulmonary or skeletal muscle reserve through cardiopulmonary exercise testing and the implementation of long-term EI based on the measurement results to address the potential deterioration in exercise capacity associated with reduced cardiac reserve, even in patients on HD that are asymptomatic and stable.

Combined endurance and resistance exercise training in heart failure with preserved ejection fraction: a randomized controlled trial

Endurance exercise training (ET) is an effective treatment in heart failure with preserved ejection fraction (HFpEF), but the efficacy of resistance training in this patient population has been only scarcely evaluated. In this multicenter, randomized trial, we evaluated the effects of combined endurance and resistance training over 12 months in patients with HFpEF. The primary endpoint was a modified Packer score, including all-cause mortality, hospitalizations classified as potentially related to heart failure or exercise and changes in peak oxygen consumption (V ̇ O 2 ), diastolic function (E/e'), New York Heart Association (NYHA) class and global self-assessment (GSA). In total, 322 patients (mean age, 70 years; 192 females (59.6%) and 130 males (40.4%)) were randomized (1:1) to ET or usual care (UC). At 12 months, the modified Packer score showed an improvement in 33 ET patients (20.5%) and in 13 UC patients (8.1%) and showed a worsening in 69 ET patients (42.9%) and in 71 UC patients (44.1%) (Kendall's tau-b = -0.073, P = 0.17). Although the primary endpoint was not met, clinically relevant differences favoring the ET group as compared to the UC group were observed for the following secondary endpoints: changes in peakV ̇ O 2 (mean difference, 1.3 ml kg-1 min-1 (95% confidence interval (CI): 0.4-2.1)) and NYHA class (odds ratio = 7.77 (95% CI: 3.73-16.21)). No significant between-group differences were observed for other secondary endpoints, including change in E/e', change in GSA, time to cardiovascular hospitalization or all-cause mortality. In conclusion, 1 year of combined endurance and resistance ET did not result in a significantly better modified Packer score, but it did result in improvements in important clinical parameters, such as peakV ̇ O 2 and NYHA class, as compared to UC. ISRCTN registration: ISRCTN86879094 .

The treatment of chronic anemia in heart failure: a global approach

Chronic anemia is an independent risk factor for mortality in patients with heart failure (HF). Restoring physiological hemoglobin (Hb) levels is essential to increase oxygen transport capacity to tissues and improve cell metabolism as well as physical and cardiac performance. Nutritional deficits and iron deficiency are the major causes of chronic anemia, but other etiologies include chronic kidney disease, inflammatory processes, and unexplained anemia. Hormonal therapy, including erythropoietin (EPO) and anabolic treatment in chronic anemia HF patients, may contribute to improving Hb levels and clinical outcomes. Although preliminary studies showed a beneficial effect of EPO therapy on cardiac efficiency and in HF, more recent studies have not confirmed this positive impact of EPO, alluding to its side effect profile. Physical exercise significantly increases Hb levels and the response of anemia to treatment. In malnourished patients and chronic inflammatory processes, low levels of anabolic hormones, such as testosterone and insulin-like growth factor-1, contribute to the development of chronic anemia. This paper aims to review the effect of nutrition, EPO, anabolic hormones, standard HF treatments, and exercise as regulatory mechanisms of chronic anemia and their cardiovascular consequences in patients with HF.

The Effectiveness of Lifestyle Interventions in Heart Failure With Preserved Ejection Fraction: A Systematic Review and Network Meta-Analysis

OBJECTIVES

To perform a network meta-analysis to determine the effectiveness of lifestyle interventions in exercise tolerance and quality of life (QoL) in people with HFpEF.

METHODS

Ten databases were searched for randomized controlled trials that evaluated a diet and/or exercise intervention in people with heart failure with preserved ejection fraction until May 2022. The co-primary outcomes were peak oxygen uptake (V̇O2peak) and Quality of Life as assessed by the Minnesota Living with Heart Failure Questionnaire (MLHFQ). We synthesized data using network meta-analysis.

RESULTS

We identified 13 trials, including a total of 869 participants, and we incorporated 6 different interventions. Improvements in V̇O2peak compared to controls were seen for all exercise interventions (2.88 [95% CI: 1.36; 4.39] mL/kg/min) for high-intensity interval training (HIIT); 2.37 [95% CI: 1.02; 3.71] mL/kg/min for low-intensity exercise (LIT) combined with a hypocaloric diet; 2.05 [95% CI: 0.81; 3.29] mL/kg/min for moderate-intensity continuous training (MICT); 1.94 [95% CI: 0.59; 3.29] mL/kg/min for LIT; 1.85 [95% CI: 0.27; 3.44] mL/kg/min for MICT combined with resistance training) but not a hypocaloric diet alone (1.26 [95%CI: -0.08; 2.61] mL/kg/min). Only HIIT (-14.45 [95%CI: -24.81; -4.10] points) and LIT (95% CI: -11.05 [-20.55; -1.54] mL/kg/min) significantly improved MLHFQ scores. Network meta-analysis indicated that HIIT was the most effective intervention for improving both V̇O2peak (mean improvement 2.88 [95% CI: 1.36; 4.39] mL/kg/min, follow-up range, 4 weeks-3 years) and QoL (-14.45 [95% CI: -24.81; -4.10] points, follow-up range, 12-26 weeks) compared to usual care.

CONCLUSIONS

This network meta-analysis indicates that HIIT is the most effective lifestyle intervention studied to improve exercise capacity and QoL, with mean improvements exceeding the minimum clinically meaningful thresholds. HIIT is likely to be an underused management strategy in HFpEF, but further studies are needed to confirm long-term improvements in symptoms and clinical outcomes.

Exercise training for patients with heart failure and preserved ejection fraction. A narrative review

Heart failure with preserved ejection fraction (HFpEF) remains a significant global health challenge, accounting for up to 50% of all heart failure cases and predominantly affecting the elderly and women. Despite advancements in therapeutic strategies, HFpEF's complexity poses substantial challenges in management, particularly due to its high comorbidity burden, including renal failure, atrial fibrillation, and obesity, among others. These comorbidities not only complicate the pathophysiology of HFpEF but also exacerbate its symptoms, necessitating a personalized approach to treatment focused on comorbidity management and symptom alleviation. In heart failure with reduced ejection fraction, exercise training (ET) was effective in improving exercise tolerance, quality of life, and reducing hospitalizations. However, the efficacy of ET in HFpEF patients remains less understood, with limited studies showing mixed results. Exercise intolerance is a key symptom in HFpEF patients, and it has a multifactorial origin since both central and peripheral oxygen mechanisms of transport and utilization are often compromised. Recent evidence underscores the potential of supervised ET in enhancing exercise tolerance and quality of life among HFpEF patients; however, the literature remains sparse and predominantly consists of small-scale studies. This review highlights the critical role of exercise intolerance in HFpEF and synthesizes current knowledge on the benefits of ET. It also calls for a deeper understanding and further research into exercise-based interventions and their underlying mechanisms, emphasizing the need for larger, well-designed studies to evaluate the effectiveness of ET in improving outcomes for HFpEF patients.

Effects of exercise training on cardiac output in subjects with heart failure with preserved ejection fraction (HFpEF) - a protocol for a systematic review and meta-analysis

BACKGROUND

Patients with heart failure with preserved ejection fraction (HFpEF) commonly experience exercise intolerance, resulting in reduced cardiorespiratory fitness. This is characterised by a decreased maximal oxygen uptake (V̇O2peak), which is determined by the product of cardiac output (CO) and arteriovenous oxygen difference (a-vDO2). While exercise training has been shown to improve V̇O2peak in HFpEF patients, the effects on CO remain unclear. The aim of this study is to systematically review and analyse the current evidence on the effects of supervised exercise training on CO in patients with HFpEF.

METHODS

We will systematically search for literature describing the effects of supervised exercise training on CO in patients with HFpEF. All eligible studies published before 30 June 2023 in the following electronic databases will be included: MEDLINE (Ovid), Embase (Ovid), SPORTDiscus (EBSCOhost), and CENTRAL (Cochrane Library). Effect sizes will be extracted for CO before and after a supervised exercise training intervention at rest and maximal exercise. Mass of heterogeneity (I2) will be calculated, and either fixed-effect models or random-effect models will be used for meta-analysis. To detect a potential publication bias, funnel plot analyses will be performed.

DISCUSSION

While several studies have reported a positive effect of supervised exercise training on cardiorespiratory fitness, attempts to assess the underlying determinants of V̇O2peak, CO, and a-vDO2 are much scarcer, especially in patients with HFpEF. From a physiological perspective, measuring CO before and after supervised exercise training seems to be a reasonable way to accurately operationalise a potential improvement in cardiac function.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022361485.

Physical Fitness Is Directly Related to Exercise Capacity and Ventilatory Response to Exercise in Men with HFrEF

Background: Heart failure (HF) patients experience reduced functional fitness level (determining the performance of routine, daily activities) and diminished exercise capacity (linked to more effortful activities). Aim: The aim of the study is to assess this relationship using functional fitness tests compared to peak VO2 and VE/VCO2 slope in the context of exercise capacity and ventilatory response to exercise. Methods: A total of 382 men with stable HFrEF (age: 61 ± 10, NYHA class I/II/III/IV: 16/50/32/2%, LVEF: 30.5 ± 8.3%) underwent cardiopulmonary exercise testing (CPX) and a Senior Fitness Test (SFT). Afterwards, the patients were divided according to the 2capacity with peak VO2 ≥ 18 mL/kg/min, those with higher or lower ventilatory responses (VE/VCO2 slope ≥ 35 vs. <35) to the exercise were compared. Results: Patients who covered shorter distances in the 6 min walking test showed worse results in the functional tests ('stand up and go', 'chair stand' and 'arm curl') and CPX (lower peak VO2, shorter exercise time and higher VE/VCO2 slope). Subjects classified into Class D demonstrated the worst results in all elements of SFT; those in Class A demonstrated the best results. Significant differences that were analogous occurred also between classes B and C. Among the participants who reached peak VO2 ≥ 18 mL/kg/min (n = 170), those with VE/VCO2 slope ≥ 35 were characterized by worse physical fitness as compared to those with VE/VCO2 < 35. Conclusion: Reduced exercise tolerance led to worsening physical function in patients with HFrEF. Moreover, limitations in physical fitness seem to be distinctive for those patients showing excessive ventilatory response to exercise slope VE/VCO2 (≥35). The Senior Fitness Test may be considered as a useful tool for assessing comprehensive functional and clinical status and risk stratification in patients with HFrEF, especially those with extremely low exercise capacity.

Supervised exercise training in heart failure with preserved ejection fraction: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) represents a prevalent and increasingly common condition. Recognized for its high incidence, there is a growing interest in exploring effective interventions, with exercise emerging as a critical component in the rehabilitation of HFpEF patients. We aim to update evidence on the impact of supervised exercise training on exercise capacity, diastolic function, arterial stiffness, and health-related quality of life (QoL) of individuals diagnosed with HFpEF.

METHODS

We systematically reviewed the literature, searching from inception to December 2023, utilizing databases such as MEDLINE (via PubMed), Google Scholar, the Cochrane Library, ClinicalTrials.gov, and the ScienceDirect portal. Statistical analyses utilized RevMan 5.4 with a random-effects model. Outcomes were presented as the weighted mean difference (WMD) alongside corresponding 95 % confidence intervals (CI), and heterogeneity was assessed using the I2 test.

RESULTS

Our final analysis included 7 randomized controlled trials (RCTs) of 346 participants, with an exercise follow-up duration of 12 to 48 weeks. In our pooled analysis, diastolic function, measured by E/A (WMD 0.01, 95 % CI: -0.04 to 0.05, p = 0.79; I2 = 0 %) and E/e' (WMD 0.87, 95 % CI: -11.09 to 12.83, p = 0.89; I2 = 69 %), showed no significant change post-exercise training. However, exercise capacity, measured by peak V̇o2 significantly improved (WMD 2.57, 95 % CI: 1.38 to 3.75, p < 0.0001; I2= 14 %). The QoL assessed by the Minnesota Living with Heart Failure (MLWHF) score remained unchanged (WMD -3.12, 95 % CI: -8.73 to 2.50, p = 0.28; I2 = 0 %), but the SF-36 physical functioning scale indicated significant improvement (WMD 9.84, 95 % CI: 2.94 to 16.73, p < 0.005; I2 = 0 %). Arterial stiffness and vascular function remained unaffected, as evidenced by arterial elastance (WMD -0.13, 95 % CI: -0.36 to 0.10, p = 0.26; I2 = 0 %) and total arterial compliance (WMD 0.12, 95 % CI: -0.26 to 0.49, p = 0.54; I2 = 0 %).

CONCLUSION

Exercise training is safe and significantly enhances exercise capacity and QoL in HFpEF, with no significant impact on diastolic function, arterial stiffness, or vascular function.

Exercise intolerance in heart failure with preserved ejection fraction: Causes, consequences and the journey towards a cure

Heart failure with preserved ejection fraction (HFpEF) accounts for over 50% of all heart failure cases nationwide and continues to rise in its prevalence. The complex, multi-organ involvement of the HFpEF clinical syndrome requires clinicians and investigators to adopt an integrative approach that considers the contribution of both cardiac and non-cardiac function to HFpEF pathophysiology. Thus, this symposium review outlines the key points from presentations covering the contributions of disease-related changes in cardiac function, arterial stiffness, peripheral vascular function, and oxygen delivery and utilization to exercise tolerance in patients with HFpEF. While many aspects of HFpEF pathophysiology remain poorly understood, there is accumulating evidence for a decline in vascular health in this patient group that may be remediable through pharmacological and lifestyle interventions and could improve outcomes and clinical status in this ever-growing patient population.

Effect of different intensity exercises on cardiopulmonary function and quality of life of patients with chronic heart failure : A systematic review and meta-analysis

BACKGROUND

Exercise-based cardiac rehabilitation has positive benefits for patients with chronic heart failure (CHF), but the choice of exercise intensity has been controversial. The aim of this systematic review and meta-analysis was to investigate the effects of different exercise intensities on cardiopulmonary function and quality of life (QoL) of patients with CHF.

METHODS

Randomized controlled trials (RCTs) of different exercise intensities applied to patients with CHF were searched in PubMed, Web of Science, the Cochrane Library, and Embase databases from inception to December 2021. Study selection and data extraction were performed simultaneously by two independent reviewers, using the Physiotherapy Evidence Database Scale (PEDro) for quality assessment of the included literature. The weighted mean differences (WMD) or standardized mean difference (SMD) were calculated by employing a fixed or random effects model. Other statistical analyses included subgroup analysis and sensitivity analysis. Quality of evidence was evaluated by the Grade of Recommendation, Assessment, Development, and Evaluation (GRADE) method.

RESULTS

Eight RCTs were included. Analyses reported no significant improvement in left ventricular ejection fractions (LVEF; WMD = 0.47, 95% CI [-4.10, 5.03], p = 0.841), peak oxygen uptake (peak VO2) (SMD = 0.38, 95% CI [-0.03, 0.80], p = 0.069) and 6‑min walking distance (6MWD) (WMD = 14.10, 95% CI [-9.51, 37.72], p = 0.242). Exercise interventions of varying intensity produced small-to-moderate beneficial effects on QoL (WMD = -4.99, 95% CI [-8.29, -1.68], p = 0.003), which appeared to be attenuated at long-term follow-up (WMD = 2.12, 95% CI [-2.91, 7.16], p = 0.409).

CONCLUSION

High-intensity exercise does not have a significant advantage over moderate-intensity exercise in improving cardiopulmonary function and aerobic capacity in patients with CHF. Beneficial changes in QoL from high-intensity exercise also appeared to decrease during long-term follow-up, indicating a cumulative effect of the efficacy of high-intensity exercise.

High-Intensity Interval Training Is Associated With Improved 10-Year Survival by Mediating Left Ventricular Remodeling in Patients With Heart Failure With Reduced and Mid-Range Ejection Fraction

BACKGROUND

This study aimed to assess the left ventricular (LV) remodeling response and long-term survival after high-intensity interval training (HIIT) in patients with various heart failure (HF) phenotypes during a 10-year longitudinal follow-up.

METHODS AND RESULTS

Among 214 patients with HF receiving guideline-directed medical therapy, those who underwent an additional 36 sessions of aerobic exercise at alternating intensities of 80% and 40% peak oxygen consumption (V ̇ $$ \dot{\mathrm{V}} $$ O2peak) were considered HIIT participants (n=96). Patients who did not undergo HIIT were considered participants receiving guideline-directed medical therapy (n=118). Participants with LV ejection fraction (EF) <40%, ≥40% and <50%, and ≥50% were considered to have HF with reduced EF, HF with mid-range EF, and HF with preserved EF, respectively. V ̇ $$ \dot{\mathrm{V}} $$ O2peak, serial LV geometry, and time to death were recorded. In all included participants, 10-year survival was better (P=0.015) for participants who underwent HIIT (80.3%) than for participants receiving guideline-directed medical therapy (68.6%). An increased V ̇ $$ \dot{\mathrm{V}} $$ O2peak, decreased minute ventilation carbon dioxide production slope, and reduced LV end-diastolic diameter were protective factors against all-cause mortality. Regarding 138 patients with HF with reduced EF (P=0.044) and 36 patients with HF with mid-range EF (P=0.036), 10-year survival was better for participants who underwent HIIT than for participants on guideline-directed medical therapy. Causal mediation analysis showed a significant mediation path for LV end-diastolic diameter on the association between HIIT and 10-year mortality in all included patients with HF (P<0.001) and those with LV ejection fraction <50% (P=0.006). HIIT also had a significant direct association with 10-year mortality in patients with HF with LV ejection fraction <50% (P=0.027) but not in those with LV ejection fraction ≥50% (n=40).

CONCLUSIONS

Reversal of LV remodeling after HIIT could be a significant mediating factor for 10-year survival in patients with HF with reduced EF and those with HF with mid-range EF.

The Effect of Weight Loss Through Lifestyle Interventions in Patients With Heart Failure With Preserved Ejection Fraction-A Systematic Review and Meta-Analysis of Randomised Controlled Trials

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) accounts for >50% of heart failure cases and is associated with significant morbidity and health system burden. To date, there have been limited treatment options proven to improve outcomes in these patients, with sodium glucose co-transporter 2 (SGLT2) inhibitors the first class of drug to demonstrate significant clinical benefits, including reductions in heart failure hospitalisation. Obesity is associated with all forms of heart failure and has been linked with worse clinical outcomes. Numerous reviews support the benefits of weight loss in heart failure, more specifically in patients with heart failure with reduced ejection fraction. However, the evidence in HFpEF patients is less clear. With limited pharmacotherapy options and growing support for weight loss in patients with HFpEF, this systematic review and meta-analysis aims to examine the effects of lifestyle interventions on weight loss and other health outcomes in patients with HFpEF.

METHODS

Web of Science, Embase, Scopus, and PubMed databases were searched to identify relevant studies up to February 2023. Included studies were randomised controlled trials (with a duration of four weeks or more) of lifestyle interventions conducted in adults with HFpEF that reported weight loss. Outcomes of interest were body weight, body mass index (BMI), blood pressure (systolic and diastolic), aerobic capacity (6-minute walk distance), New York Heart Association (NYHA) Functional Classification, self-reported health quality of life (Minnesota Living with Heart Failure Questionnaire; MLHFQ), and N-terminal pro B-Type Natriuretic Peptide (NT-proBNP) levels. Review Manager software was used to conduct random effect meta-analyses, forest plots were generated for each outcome, and between-study heterogeneity was estimated using the I2 test statistic. Risk-of-bias assessment used the Cochrane risk-of-bias tool, and the certainty of the evidence was assessed using GRADE.

RESULTS

From 2,282 records identified, six studies with a total of 375 participants, between three to six months in duration, were included in this systematic review and meta-analysis. Lifestyle interventions consisted of diet only, exercise only, combination of diet and exercise, and education and exercise. Over a mean follow-up of 4.5 months, pooled effects of the interventions were associated with a reduction in body weight of >5kg (weight mean difference (WMD): -5.30 kg; 95% CI: -8.72 to -1.87; p=0.002), and a reduction in resting systolic (WMD: -2.98 mmHg; 95% CI: -4.20 to -1.76; p<0.001) and diastolic blood pressure (WMD: -4.51 mmHg; 95% CI: -8.39 to -0.64; p=0.02) compared with those who received usual care. Interventions also improved 6-minute walk distance (WMD: 43.63 m; 95% CI: 22.28 to 64.97; p<0.001), NYHA class (WMD: -0.54; 95% CI: -0.75 to -0.33; p<0.001), and MLHFQ score (WMD: -17.77; 95% CL: -19.00 to -16.53; p<0.001).

CONCLUSION

In patients with HFpEF, lifestyle intervention was associated with a significant reduction in body weight and had favourable effects on blood pressure, aerobic capacity, NYHA class, and health-related quality of life. Further research is needed in this population to examine the feasibility and durability of weight loss interventions and to examine the potential impact on hard clinical endpoints.

Effect of different types of aerobic training on peak VO2 and ejection fraction for diastolic heart failure patients; a comparative randomized control trial

BACKGROUND

Heart failure is described by a lack of confirmed efficient therapies and exercise intolerance. Engagement in physical activity decreases the possibility of adverse cardiovascular consequences involving heart failure.

THE PURPOSE OF THE STUDY

Determine the effect of different types of aerobic training on peak VO2 and ejection fraction in diastolic heart failure patients.

SUBJECT AND METHODS

The study was designed as a randomized control trail. Forty-eight eligible male patients with diastolic heart failure, aged between 50 and 65 years old, enrolled in this study. They were picked up from Police hospital outpatient clinic and were assigned to 2 equal groups in numbers. The first group (A) received aerobic exercise for the upper limb in the form of arm ergometer exercises, while the second group (B) received aerobic exercise for the lower limb in the form of cycling. Training duration for both groups was 3 sessions/week for 12 weeks. Peak VO2, and ejection fraction of both groups were measured and compared pre- and post-treatment.

RESULTS

There was no significant difference (p > 0.05) in the ejection fraction between groups post-treatment. However, a significant increase (p < 0.001) was observed in the peak VO2 of group B when compared to group A post-treatment.

CONCLUSION

There is no effect of different types of aerobic training on ejection fraction in diastolic heart failure patients, but lower limb exercise is more effective than upper limb exercise in improving peak VO2 in diastolic heart failure patients. Therefore, the current study recommended the use of lower limb exercise over upper limb exercise in training diastolic heart failure patients.

CLINICAL TRIAL REGISTRATION

The study was registered in ClinicalTrial.gov as a clinical trial ID (NCT05637125).

Exercise and cardiac rehabilitation in hypertensive patients with heart failure with preserved ejection fraction: A position statement on behalf of the Working Group of Arterial Hypertension of the Hellenic Society of Cardiology

Arterial hypertension is a major cause of cardiovascular morbidity and mortality and the most common cause of comorbidity in heart failure (HF) with preserved ejection fraction (HFpEF). As an adjunct to medication, healthy lifestyle modifications with emphasis on regular exercise are strongly recommended by both the hypertension and the HF guidelines of the European Society of Cardiology. Several long-term studies have shown that exercise is associated with a reduction in all-cause mortality, a favorable cardiac and metabolic risk profile, mental health, and other non-cardiovascular benefits, as well as an improvement in overall quality of life. However, the instructions for the prescriptive or recommended exercise in hypertensive patients and, more specifically, in those with HFpEF are not well defined. Moreover, the evidence is based on observational or small randomized studies, while well-designed clinical trials are lacking. Despite the proven benefit and the guidelines' recommendations, exercise programs and cardiac rehabilitation in patients with hypertensive heart disease and HFpEF are grossly underutilized. This position statement provides a general framework for exercise and exercise-based rehabilitation in patients with hypertension and HFpEF, guides clinicians' rehabilitation strategies, and facilitates clinical practice. It has been endorsed by the Working Group of Arterial Hypertension of the Hellenic Society of Cardiology and is focused on the Health Care System in Greece.

Exercise training affects hemodynamics and exercise capacity in cases of heart failure with preserved ejection fraction: a non-randomized controlled trial in individuals aged 65-80 years

Introduction

Exercise training is an established intervention method for improving exercise capacity and survival rates in patients with heart failure with preserved ejection fraction (HFpEF). However, most reports have focused on European and American patients, with limited data regarding the effects of exercise training on cardiac function, hemodynamics, and exercise capacity in East Asian patients. This study investigated the effects of exercise training on cardiac function, hemodynamics, and exercise capacity in Japanese patients aged 65-80 years with HFpEF.

Methods

This single-center, open-label, non-randomized, controlled trial prospectively enrolled 99 outpatients. Eligibility criteria for HFpEF patients were an HFA score ≥5 in addition to clinical symptoms of heart failure and left ventricular diastolic dysfunction. Exercise training in the intervention group consisted of aerobic exercise and strength training thrice weekly for 5 months. Patients in the control group continued the usual treatment for 5 months. Resting cardiac function was evaluated using echocardiography. Peak oxygen uptake (peakVO2), ventilatory equivalent (VE) vs. carbon dioxide output (VCO2) slope, peak cardiac output index, and arteriovenous oxygen difference were calculated using cardiopulmonary exercise testing combined with impedance cardiography.

Results

After 5 months of exercise training, remarkable interactions were observed, with peakVO2 as the primary outcome. Additionally, significant interactions were observed between hemodynamic indices and some echocardiographic parameters. The mean percentage change in peakVO2 from baseline was 8.3% in the intervention group. Fifteen study participants (30.1%) in the intervention group achieved a clinically meaningful change of 3.0 ml/min/kg (10% improvement) in peakVO2 from baseline. The group with 3.0 ml/min/kg or 10% improvement in peakVO2 from baseline had a considerably lower prevalence of diabetes mellitus and VE vs. VCO2 slope and considerably higher left atrial-global longitudinal strain values than the group without any notable improvements.

Conclusions

Although exercise training can help improve exercise intolerance in Japanese patients aged 65-80 years with HFpEF, its benefits are limited. Our results suggest that HFpEF, complicated by diabetes mellitus and decreased ventilatory efficiency during exercise, may require reconsideration of intervention strategies. This trial was registered with the University Hospital Medical Information Network, a trial registry in Japan (registration number: UMIN000045474).

Breathing pattern and pulmonary gas exchange in elderly patients with and without left ventricular dysfunction-modification with exercise-based cardiac rehabilitation and prognostic value

Background

Inefficient ventilation is an established prognostic marker in patients with heart failure. It is not known whether inefficient ventilation is also linked to poor prognosis in patients with left ventricular dysfunction (LVD) but without overt heart failure.

Objectives

To investigate whether inefficient ventilation in elderly patients with LVD is more common than in patients without LVD, whether it improves with exercise-based cardiac rehabilitation (exCR), and whether it is associated with major adverse cardiovascular events (MACE).

Methods

In this large multicentre observational longitudinal study, patients aged ≥65 years with acute or chronic coronary syndromes (ACS, CCS) without cardiac surgery who participated in a study on the effectiveness of exCR in seven European countries were included. Cardiopulmonary exercise testing (CPET) was performed before, at the termination of exCR, and at 12 months follow-up. Ventilation (VE), breathing frequency (BF), tidal volume (VT), and end-expiratory carbon dioxide pressure (PETCO2) were measured at rest, at the first ventilatory threshold, and at peak exercise. Ventilatory parameters were compared between patients with and without LVD (based on cardio-echography) and related to MACE at 12 month follow-up.

Results

In 818 patients, age was 72.5 ± 5.4 years, 21.9% were women, 79.8% had ACS, and 151 (18%) had LVD. Compared to noLVD, in LVD resting VE was increased by 8%, resting BF by 6%, peak VE, peak VT, and peak PETCO2 reduced by 6%, 8%, and 5%, respectively, and VE/VCO2 slope increased by 11%. From before to after exCR, resting VE decreased and peak PETCO2 increased significantly more in patients with compared to without LVD. In LVD, higher resting BF, higher nadir VE/VCO2, and lower peak PETCO2 at baseline were associated with MACE.

Conclusions

Similarly to patients with HF, in elderly patients with ischemic LVD, inefficient resting and exercise ventilation was associated with worse outcomes, and ExCR alleviated abnormal breathing patterns and gas exchange parameters.

Comparative Effect of Two Types of Physical Exercise for the Improvement of Exercise Capacity, Diastolic Function, Endothelial Function and Arterial Stiffness in Participants with Heart Failure with Preserved Ejection Fraction (ExIC-FEp Study): Protocol for a Randomized Controlled Trial

(1) Background: Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for approximately 50% of all patients with HF. In the absence of pharmacological treatments that have been successful in reducing mortality or morbidity in this pathology, physical exercise is recognized as an important adjunct in the treatment of HF. Therefore, the objective of this study is to compare the efficacy of combined training and high intensity interval training (HIIT) on exercise capacity, diastolic function, endothelial function, and arterial stiffness in participants with HFpEF. (2) Methods: The ExIC-FEp study will be a single-blind, 3-arm, randomized clinical trial (RCT) conducted at the Health and Social Research Center of the University of Castilla-La Mancha. Participants with HFpEF will be randomly assigned (1:1:1) to the combined exercise, HIIT or control group to evaluate the efficacy of physical exercise programs on exercise capacity, diastolic function, endothelial function, and arterial stiffness. All participants will be examined at baseline, at three months and at six months. (3) Results: The findings of this study will be published in a peer-reviewed journal. (4) Conclusions: This RCT will represent a significant advance in the available scientific evidence on the efficacy of physical exercise in the treatment of HFpEF.

Supervised Exercise Training for Chronic Heart Failure With Preserved Ejection Fraction: A Scientific Statement From the American Heart Association and American College of Cardiology

Heart failure with preserved ejection fraction (HFpEF) is one of the most common forms of heart failure; its prevalence is increasing, and outcomes are worsening. Affected patients often experience severe exertional dyspnea and debilitating fatigue, as well as poor quality of life, frequent hospitalizations, and a high mortality rate. Until recently, most pharmacological intervention trials for HFpEF yielded neutral primary outcomes. In contrast, trials of exercise-based interventions have consistently demonstrated large, significant, clinically meaningful improvements in symptoms, objectively determined exercise capacity, and usually quality of life. This success may be attributed, at least in part, to the pleiotropic effects of exercise, which may favorably affect the full range of abnormalities-peripheral vascular, skeletal muscle, and cardiovascular-that contribute to exercise intolerance in HFpEF. Accordingly, this scientific statement critically examines the currently available literature on the effects of exercise-based therapies for chronic stable HFpEF, potential mechanisms for improvement of exercise capacity and symptoms, and how these data compare with exercise therapy for other cardiovascular conditions. Specifically, data reviewed herein demonstrate a comparable or larger magnitude of improvement in exercise capacity from supervised exercise training in patients with chronic HFpEF compared with those with heart failure with reduced ejection fraction, although Medicare reimbursement is available only for the latter group. Finally, critical gaps in implementation of exercise-based therapies for patients with HFpEF, including exercise setting, training modalities, combinations with other strategies such as diet and medications, long-term adherence, incorporation of innovative and more accessible delivery methods, and management of recently hospitalized patients are highlighted to provide guidance for future research.

Supervised Exercise Training for Chronic Heart Failure With Preserved Ejection Fraction: A Scientific Statement From the American Heart Association and American College of Cardiology

Heart failure with preserved ejection fraction (HFpEF) is one of the most common forms of heart failure; its prevalence is increasing, and outcomes are worsening. Affected patients often experience severe exertional dyspnea and debilitating fatigue, as well as poor quality of life, frequent hospitalizations, and a high mortality rate. Until recently, most pharmacological intervention trials for HFpEF yielded neutral primary outcomes. In contrast, trials of exercise-based interventions have consistently demonstrated large, significant, clinically meaningful improvements in symptoms, objectively determined exercise capacity, and usually quality of life. This success may be attributed, at least in part, to the pleiotropic effects of exercise, which may favorably affect the full range of abnormalities-peripheral vascular, skeletal muscle, and cardiovascular-that contribute to exercise intolerance in HFpEF. Accordingly, this scientific statement critically examines the currently available literature on the effects of exercise-based therapies for chronic stable HFpEF, potential mechanisms for improvement of exercise capacity and symptoms, and how these data compare with exercise therapy for other cardiovascular conditions. Specifically, data reviewed herein demonstrate a comparable or larger magnitude of improvement in exercise capacity from supervised exercise training in patients with chronic HFpEF compared with those with heart failure with reduced ejection fraction, although Medicare reimbursement is available only for the latter group. Finally, critical gaps in implementation of exercise-based therapies for patients with HFpEF, including exercise setting, training modalities, combinations with other strategies such as diet and medications, long-term adherence, incorporation of innovative and more accessible delivery methods, and management of recently hospitalized patients are highlighted to provide guidance for future research.

Cerebral oxygenation during cardiopulmonary exercise testing in cardiorespiratory diseases: A systematic review

BACKGROUND

Cardiopulmonary exercise testing (CPET) is the gold standard for analyzing cardiorespiratory fitness and integrating physiological responses. However, the presence of chronic diseases may compromise cerebral hemodynamic responses during CPET. In addition, the acute response of cerebral oxygenation during incremental CPET may identify abnormal behavior and ensure greater safety for patients with cardiovascular, respiratory, and metabolic diseases.

OBJECTIVE

To summarize the cerebral oxygenation acute response during CPET of patients with cardiovascular, metabolic, or respiratory diseases.

METHODS

From inception to 23rd September 2022, five databases (PubMed, SCOPUS, Web of Science, Embase and CINAHAL) were searched for cross-sectional studies performing incremental CPET and measuring the cerebral oxygenation acute response in cardiovascular, metabolic, or respiratory diseases compared with healthy individuals. The Downs and Black tool assessed the risk of bias of the studies.

RESULTS

We included seven studies with 428 participants (305 men and 123 women), aged 43 to 70 years. Of these, 101 had heart failure NYHA II and III; 77 idiopathic dilated cardiomyopathy; 33 valvular disease; 25 coronary heart disease; 22 pulmonary arterial hypertension; 15 had severe obstructive sleep apnea (OSA) and 166 were apparently healthy. There was no eligible article with metabolic disease. There was a lower magnitude increase in cerebral oxygenation of cardiovascular patients compared with the healthy individuals during the CPET. Furthermore, pulmonary arterial hypertension patients presented increased cerebral oxygen extraction, differently to those with severe OSA.

CONCLUSION

Considering the heterogeneity of the included studies, patients with cardiovascular disease may suffer from reduced cerebral oxygen supply, and individuals with OSA presented lower brain oxygen extraction during the CPET. Future studies should aim for strategies to improve cerebral oxygenation to ensure greater safety at CPET of cardiovascular and OSA patients. An acute response pattern for metabolic and other respiratory diseases was not established.

The Role of Exercise-based Cardiac Rehabilitation in Heart Failure

Exercise-based cardiac rehabilitation (EBCR) is a treatment modality for patients with heart failure (HF) that has withstood the test of time. It has continued to show benefits even in the current era of pharmacotherapeutics for HF. Participation in a multidisciplinary comprehensive EBCR programme reduces mortality and morbidity, has a multitude of physiological benefits, and improves cardiovascular risk factor control and quality of life. Despite this, historical barriers to enrolment and uptake remain. Strategies to overcome these, as well as alternative delivery methods of EBCR in HF patients, are emerging and include telerehabilitation, focus on special groups and emphasis on behavioural change. This review provides oversight on the modalities of exercise training in HF as well as their benefits and gives an overview of barriers to the utilisation of EBCR along with future progress in the field.

Skeletal muscle abnormalities in heart failure with preserved ejection fraction

Almost half of all heart failure (HF) disease burden is due to HF with preserved ejection fraction (HFpEF). The primary symptom in patients with HFpEF, even when well compensated, is severe exercise intolerance and is associated with their reduced quality of life. Recently, studies showed that HFpEF patients have multiple skeletal muscle (SM) abnormalities, and these are associated with decreased exercise intolerance. The SM abnormalities are likely intrinsic to the HFpEF syndrome, not a secondary consequence of an epiphenomenon. These abnormalities are decreased muscle mass, reduced type I (oxidative) muscle fibers, and reduced type I-to-type II fiber ratio as well as a reduced capillary-to-fiber ratio, abnormal fat infiltration into the thigh SM, increased levels of atrophy genes and proteins, reduction in mitochondrial content, and rapid depletion of high-energy phosphate during exercise with markedly delayed repletion of high-energy phosphate during recovery in mitochondria. In addition, patients with HFpEF have impaired nitric oxide bioavailability, particularly in the microvasculature. These SM abnormalities may be responsible for impaired diffusive oxygen transport and/or impaired SM oxygen extraction. To date, exercise training (ET) and caloric restriction are some of the interventions shown to improve outcomes in HFpEF patients. Improvements in exercise tolerance following aerobic ET are largely mediated through peripheral SM adaptations with minimal change in central hemodynamics and highlight the importance of targeting SM to improve exercise intolerance in HFpEF. Focusing on the abnormalities mentioned above may improve the clinical condition of patients with HFpEF.

The effect of exercise training and physiotherapy on left and right heart function in heart failure with preserved ejection fraction: a systematic literature review

The impact of exercise training and physiotherapy on heart function and pulmonary circulation parameters in heart failure with preserved ejection fraction (HFpEF) patients is uncertain. Hence, we performed a systematic review of published trials studying physical training in HFpEF population, with a focus on exercise and physiotherapy effect on left ventricular (LV), right ventricular (RV) morphological, functional, and pulmonary circulation parameters. We searched Cochrane Library and MEDLINE/PubMed for trials that evaluated the effect of exercise training and/or physiotherapy in adult HFpEF patients (defined as LVEF ≥ 45%), including publications until March 2021. Our systematic review identified eighteen articles (n = 418 trained subjects, 4 to 52 weeks of training) and covered heterogeneous trials with various populations, designs, methodologies, and interventions. Five of twelve trials revealed a significant reduction of mitral E/e' ratio after the training (- 1.2 to - 4.9). Seven studies examined left atrial volume index; three of them showed its decrease (- 3.7 to - 8 ml/m2). Findings were inconsistent regarding improvement of cardiac output, E/A ratio, and E wave DecT and uncertain for RV function and pulmonary hypertension parameters. For now, no reliable evidence about rehabilitation effect on HFpEF cardiac mechanisms is available. There are some hypotheses generating findings on potential positive effects to parameters of LV filling pressure (E/e'), left atrium size, cardiac output, and RV function. This encourages a broader and more complex assessment of parameters reflecting cardiac function in future HFpEF exercise training studies.

Change in Central Cardiovascular Function in Response to Intense Interval Training: A Systematic Review and Meta-analysis

INTRODUCTION

High-intensity interval training and sprint interval training significantly increase maximal oxygen uptake (V̇O 2max ), which enhances endurance performance and health status. Whether this response is due to increases in central cardiovascular function (cardiac output (CO) and blood volume) or peripheral factors is unknown.

PURPOSE

This study aimed to conduct a systematic review and meta-analysis to assess the effects of high-intensity interval training and sprint interval training (referred to as intense interval training) on changes in central cardiovascular function.

METHODS

We performed a systematic search of eight databases for studies denoting increases in V̇O 2max in which CO, stroke volume (SV), blood volume, plasma volume, end-diastolic/systolic volume, or hematocrit were measured.

RESULTS

Forty-five studies were included in this analysis, comprising 946 men and women of various health status (age and V̇O 2max , 20-76 yr and 13-61 mL·kg -1 ·min -1 ) who performed 6-96 sessions of interval training. Results showed an increase in V̇O 2max with intense interval training that was classified as a large effect ( d = 0.83). SV ( d = 0.69), and CO ( d = 0.49) had moderate effect sizes in response to intense interval training. Of 27 studies in which CO was measured, 77% exhibited significant increases in resting CO or that obtained during exercise. Similarly, 93% of studies revealed significant increases in SV in response to intense interval training. Effect sizes for these outcomes were larger for clinical versus healthy populations. Plasma volume, blood volume, and hematocrit had small effect sizes after training ( d = 0.06-0.14).

CONCLUSIONS

Increases in V̇O 2max demonstrated with intense interval training are attendant with increases in central O 2 delivery with little contribution from changes in hematocrit, blood volume, or plasma volume.

High-intensity interval training to promote cerebral oxygenation and affective valence during exercise in individuals with obesity

Left/right prefrontal cortex (PFC) activation is linked to positive/negative affects, respectively. Besides, larger left PFC oxygenation during exercise relates to higher cardiorespiratory fitness (CRF). High-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) in improving CRF. The influence of training on PFC oxygenation and affects during exercise in individuals with obesity is, however, currently unknown. Twenty participants with obesity (14 males, 48 ± 8 years, body-mass index = 35 ± 6 kg·m^-2) were randomised to MICT [50% peak work rate (WR_peak)] or HIIT (1-min bouts 100% WR_peak; 3 sessions/week, 8 weeks). Before/after training, participants completed an incremental ergocycle test. Near-infrared spectroscopy and the Feeling Scale assessed PFC oxygenation and affects during exercise, respectively. Improvements in CRF (e.g., WR_peak: 32 ± 14 vs 20 ± 13 W) were greater after HIIT vs MICT (p < 0.05). Only HIIT induced larger left PFC oxygenation (haemoglobin difference from 7 ± 6 to 10 ± 7 μmol) and enhanced affective valence (from 0.7 ± 2.9 to 2.2 ± 2.0; p < 0.05) at intensities ≥ second ventilatory threshold. Exercise-training induced changes in left PFC oxygenation correlated with changes in CRF [e.g., WR_peak (% predicted), r = 0.46] and post-training affective valence (r = 0.45; p < 0.05). HIIT specifically improved left PFC oxygenation and affects during exercise in individuals with obesity. Implementing HIIT in exercise programmes may therefore have relevant implications for the management of obesity, since greater affective response to exercise is thought to be associated with future commitment to physical activity.

Effects of Exercise on Heart Failure with Preserved Ejection Fraction: An Updated Review of Literature

Heart failure with preserved ejection fraction (HFpEF) represents the most common HF phenotype of patients aged > 65 years, with an incidence and a prevalence that are constantly growing. The HFpEF cardinal symptom is exercise intolerance (EI), defined as the impaired ability to perform physical activity and to reach the predicted age-related level of exercise duration in the absence of symptoms—such as fatigue or dyspnea—and is associated with a poor quality of life, a higher number of hospitalizations, and poor outcomes. The evidence of the protective effect between exercise and adverse cardiovascular outcomes is numerous and long-established. Regular exercise is known to reduce cardiovascular events and overall mortality both in apparently healthy individuals and in patients with established cardiovascular disease, representing a cornerstone in the prevention and treatment of many cardio-metabolic conditions. Several studies have investigated the role of exercise in HFpEF patients. The present review aims to dwell upon the effects of exercise on HFpEF. For this purpose, the relevant data from a literature search (PubMed, EMBASE, and Medline) were reviewed. The analysis of these studies underlines the fact that exercise training programs improve the cardiorespiratory performance of HFpEF patients in terms of the increase in peak oxygen uptake, the 6 min walk test distance, and the ventilatory threshold; on the other hand, diastolic or systolic functions are generally unchanged or only partially modified by exercise, suggesting that multiple mechanisms contribute to the improvement of exercise tolerance in HFpEF patients. In conclusion, considering that exercise training programs are able to improve the cardiorespiratory performance of HFpEF patients, the prescription of exercise training programs should be encouraged in stable HFpEF patients, and further research is needed to better elucidate the pathophysiological mechanisms underpinning the beneficial effects described.

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSIONS

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

Effects of Intermittent Hypoxia-Hyperoxia on Performance- and Health-Related Outcomes in Humans: A Systematic Review

BACKGROUND

Intermittent hypoxia applied at rest or in combination with exercise promotes multiple beneficial adaptations with regard to performance and health in humans. It was hypothesized that replacing normoxia by moderate hyperoxia can increase the adaptive response to the intermittent hypoxic stimulus.

OBJECTIVE

Our objective was to systematically review the current state of the literature on the effects of chronic intermittent hypoxia-hyperoxia (IHH) on performance- and health-related outcomes in humans.

METHODS

PubMed, Web of Science™, Scopus, and Cochrane Library databases were searched in accordance with PRISMA guidelines (January 2000 to September 2021) using the following inclusion criteria: (1) original research articles involving humans, (2) investigation of the chronic effect of IHH, (3) inclusion of a control group being not exposed to IHH, and (4) articles published in peer-reviewed journals written in English.

RESULTS

Of 1085 articles initially found, eight studies were included. IHH was solely performed at rest in different populations including geriatric patients (n = 1), older patients with cardiovascular (n = 3) and metabolic disease (n = 2) or cognitive impairment (n = 1), and young athletes with overtraining syndrome (n = 1). The included studies confirmed the beneficial effects of chronic exposure to IHH, showing improvements in exercise tolerance, peak oxygen uptake, and global cognitive functions, as well as lowered blood glucose levels. A trend was discernible that chronic exposure to IHH can trigger a reduction in systolic and diastolic blood pressure. The evidence of whether IHH exerts beneficial effects on blood lipid levels and haematological parameters is currently inconclusive. A meta-analysis was not possible because the reviewed studies had a considerable heterogeneity concerning the investigated populations and outcome parameters.

CONCLUSION

Based on the published literature, it can be suggested that chronic exposure to IHH might be a promising non-pharmacological intervention strategy for improving peak oxygen consumption, exercise tolerance, and cognitive performance as well as reducing blood glucose levels, and systolic and diastolic blood pressure in older patients with cardiovascular and metabolic diseases or cognitive impairment. However, further randomized controlled trials with adequate sample sizes are needed to confirm and extend the evidence. This systematic review was registered on the international prospective register of systematic reviews (PROSPERO-ID: CRD42021281248) ( https://www.crd.york.ac.uk/prospero/ ).

The impact of type-2 diabetes mellitus on cardiac rehabilitation outcomes: a meta-analysis

OBJECTIVE

To determine the impact of cardiac rehabilitation (CR) on changes in functional capacity (FC) among patients with CVD and a type-2 diabetes mellitus (T2DM) co-morbidity compared to non-T2DM patients.

DATA SOURCE

A systematic review and meta-analysis of randomized control trials were completed using PubMed, CINAHL, and Web of Science in January 2021.

STUDY SELECTION

Articles were included if they compared CR patients with T2DM to those without T2DM (non-T2DM).

DATA EXTRACTION

The primary outcome variable was FC change from pre to post CR reported as maximal or peak oxygen consumption (VO₂max, VO₂peak), and peak metabolic equivalent (METs). Risk of bias was assessed using the Cochrane risk of bias tool. A random-effects model sub-group meta-analysis was conducted. A diabetes co-morbidity was selected for the subgroup analysis with CVD patients being reported as T2DM or non-T2DM.

DATA SYNTHESIS

Twelve studies with total sample of 15,672 patients were extracted. Average change in peak METs was 1.41±1.76 among non-T2DM and 1.08±1.57 among T2DM patients after CR. Change in FC was significantly lower among T2DM patients (Z-value=2.14; g = -0.42; 95% CI [-0.86 - 0.01]; p=0.03).

CONCLUSION

CVD patients with T2DM experience less robust improvements in FC in response to CR compared to patients with CVD alone. A better understanding of the relationship between T2DM and FC vital step in informing exercise prescription in CR for patients with T2DM and CVD. The lack of understanding the role of T2DM onset and progression is a limitation to this study.

The Role of Systemic Microvascular Dysfunction in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a condition with increasing incidence, leading to a health care problem of epidemic proportions for which no curative treatments exist. Consequently, an urge exists to better understand the pathophysiology of HFpEF. Accumulating evidence suggests a key pathophysiological role for coronary microvascular dysfunction (MVD), with an underlying mechanism of low-grade pro-inflammatory state caused by systemic comorbidities. The systemic entity of comorbidities and inflammation in HFpEF imply that patients develop HFpEF due to systemic mechanisms causing coronary MVD, or systemic MVD. The absence or presence of peripheral MVD in HFpEF would reflect HFpEF being predominantly a cardiac or a systemic disease. Here, we will review the current state of the art of cardiac and systemic microvascular dysfunction in HFpEF (Graphical Abstract), resulting in future perspectives on new diagnostic modalities and therapeutic strategies.

Effect of different intensity exercises intervention on cardiovascular functions and quality of life on patients with chronic heart failure: A protocol for systematic review and meta-analysis

BACKGROUND

Exercise training can improve exercise capacity, quality of life, and reduce hospitalization time in chronic heart failure (CHF) patients. Various training protocols have been studied in CHF, but there is no consensus on the optimal exercise intensity for the rehabilitation of cardiac patients. Therefore, systematic evaluation of the effects of different exercise intensities on the efficacy of cardiac function and quality of life in patients with CHF was done.

METHODS

Computer searches of PubMed, Web of Science, The Cochrane Library, Embase, SinoMed, the China National Knowledge Infrastructure, Wanfang, and VIP databases were conducted to collect randomized controlled trials of different exercise intensities applied to patients with CHF. Study selection and data extraction will be performed simultaneously by two independent reviewers, using the PEDro scale for quality assessment of the included literature. Publication bias will be assessed by funnel plot, and Begg and Egger tests. The I2 statistic and the chi-square (χ2) test will be used to assess heterogeneity. In addition, subgroup analyses will be performed for different left ventricular ejection fraction populations and different intervention cycles. All meta-analyses will be performed using Revman5.3 software.

RESULTS

The present study is a systematic review and meta-analysis program with no results. Data analysis will be completed after the program has been completed.

CONCLUSION

This meta-analysis may provide more reliable, evidence-based evidence for the choice of exercise intensity in patients with CHF.

REGISTRATION NUMBER

CRD42021276529.

High-Intensity Interval Training for Heart Failure Patients With Preserved Ejection Fraction (HIT-HF)-Rational and Design of a Prospective, Randomized, Controlled Trial

Background: The pathophysiology of HF with preserved ejection fraction (HFpEF) has not yet been fully understood and HFpEF is often misdiagnosed. Remodeling and fibrosis stimulated by inflammation appear to be main factors for the progression of HFpEF. In contrast to patients with HF with reduced ejection fraction, medical treatment in HFpEF is limited to relieving HF symptoms. Since mortality in HFpEF patients remains unacceptably high with a 5-year survival rate of only 30%, new treatment strategies are urgently needed. Exercise seems to be a valid option. However, the optimal training regime still has to be elucidated. Therefore, the aim of the study is to investigate the effects of a high-intensity interval (HIT) training vs. a moderate continuous training (MCT) on exercise capacity and disease-specific mechanisms in a cohort of patients with HFpEF. Methods: The proposed study will be a prospective, randomized controlled trial in a primary care setting including 86 patients with stable HFpEF. Patients will undergo measurements of exercise capacity, disease-specific blood biomarkers, cardiac and arterial vessel structure and function, total hemoglobin mass, metabolic requirements, habitual physical activity, and quality of life (QoL) at baseline and follow-up. After the baseline visit, patients will be randomized to the intervention or control group. The intervention group (n = 43) will attend a supervised 12-week HIT on a bicycle ergometer combined with strength training. The control group (n = 43) will receive an isocaloric supervised MCT combined with strength training. After 12 weeks, study measurements will be repeated in all patients to quantify the effects of the intervention. In addition, telephone interviews will be performed at 6 months, 1, 2, and 3 years after the last visit to assess clinical outcomes and QoL. Discussion: We anticipate clinically significant changes in exercise capacity, expressed as VO_2peak, as well as in disease-specific mechanisms following HIT compared to MCT. Moreover, the study is expected to add important knowledge on the pathophysiology of HFpEF and the clinical benefits of a training intervention as a novel treatment strategy in HFpEF patients, which may help to improve both QoL and functional status in affected patients. Trial registration: ClinicalTrials.gov, identifier: NCT03184311, Registered 9 June 2017.

Exercise training for prevention and treatment of older adults with heart failure with preserved ejection fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) is the most rapidly increasing form of HF, occurs primarily in older women, and is associated with high rates of morbidity, mortality, and health care expenditures. In the highest age decile (≥90 years old), nearly all patients with HFpEF. As our understanding of the disease has grown in the last few years, we now know that HFpEF is a systemic disorder influenced by aging processes. The involvement of this broad collection of abnormalities in HFpEF, the recognition of the high frequency and impact of noncardiac comorbidities, and systemic, multiorgan involvement, and its nearly exclusive existence in older persons, has led to the recognition of HFpEF as a true geriatric syndrome. Most of the conventional therapeutics used in other cardiac diseases have failed to improve HFpEF patient outcomes significantly. Several recent studies have evaluated exercise training (ET) as a therapeutic management strategy in patients with HFpEF. Although these studies were not designed to address clinical endpoints, such as HF hospitalizations and mortality, they have shown that ET is a safe and effective intervention to improve peak oxygen consumption, physical function, and quality of life in clinically stable HF patients. Recently, a progressive, multidomain physical rehabilitation study among older adults showed that it is feasible in older patients with acute decompensated HF who have high frailty and comorbidities and showed improvement in physical function. However, the lack of Centers for Medicare and Medicaid Services coverage can be a major barrier to formal cardiac rehabilitation in older HFpEF patients. Unfortunately, insistence upon demonstration of mortality improvement before approving reimbursement overlooks the valuable and demonstrated benefits of physical function and life quality.

Optimizing Outcomes in Cardiac Rehabilitation: The Importance of Exercise Intensity

Exercise based cardiac rehabilitation (CR) is recognized internationally as a class 1 clinical practice recommendation for patients with select cardiovascular diseases and heart failure with reduced ejection fraction. Over the past decade, several meta-analyses have generated debate regarding the effectiveness of exercise-based CR for reducing all-cause and cardiovascular mortality. A common theme highlighted in these meta-analyses is the heterogeneity and/or lack of detail regarding exercise prescription methodology within CR programs. Currently there is no international consensus on exercise prescription for CR, and exercise intensity recommendations vary considerably between countries from light-moderate intensity to moderate intensity to moderate-vigorous intensity. As cardiorespiratory fitness [peak oxygen uptake (VO₂peak)] is a strong predictor of mortality in patients with coronary heart disease and heart failure, exercise prescription that optimizes improvement in cardiorespiratory fitness and exercise capacity is a critical consideration for the efficacy of CR programming. This review will examine the evidence for prescribing higher-intensity aerobic exercise in CR, including the role of high-intensity interval training. This discussion will highlight the beneficial physiological adaptations to pulmonary, cardiac, vascular, and skeletal muscle systems associated with moderate-vigorous exercise training in patients with coronary heart disease and heart failure. Moreover, this review will propose how varying interval exercise protocols (such as short-duration or long-duration interval training) and exercise progression models may influence central and peripheral physiological adaptations. Importantly, a key focus of this review is to provide clinically-relevant recommendations and strategies to optimize prescription of exercise intensity while maximizing safety in patients attending CR programs.

Impact of cardiac rehabilitation on left ventricular diastolic function and exercise capacity in patients treated with percutaneous coronary intervention after acute coronary event

BACKGROUND

Study examines the influence of cardiac rehabilitation program (CR) on left ventricular diastolic dysfunction (LVDD), functional capacity and major cardiovascular risk factors (CVRF) in patients after with PCI resolved acute coronary syndrome (ACS).

METHODS

We performed a non-randomised study included a total of 85 subjects after resolved ACS, with left ventricular ejection fraction (LVEF) ≥ 45% and LVDD, without heart failure. Subjects were divided into control (N = 29) and intervention group (N = 56), depending on CR program attendance consisted of exercise training sessions for 12 weeks, 3 times per/week, 30 min per session. Initially and after 12 weeks, patients were subjected to echocardiography to assess LV filling pressure (E/e') as well as CPET to asses improvement in peak VO_2.

RESULTS

Initially subjects were similar in CVRF, LVDD and CPET parameters (p > 0.05). Following CR, the intervention group demonstrated a significant improvement in E/e' (8.0 ± 3.0 vs 7.0 ± 2.2; p < 0.05), compared to the control group (8.4 ± 3.0 vs 9.0 ± 3.1; p > 0.05), as well as a significant improvement in peak VO₂ (23.2 ± 5.0 ml/kg/min vs 24.8 ± 5.8 ml/kg/min; p < 0.001). Control group also exhibited significant worsening in peak VO₂ without CR (23.0 ± 4.0 vs 21.2 ± 4.1 ml/kg/min; p = 0.02). CVRF improved in both groups, except for glycaemia levels and body mass index, which improved only in the intervention group (p < 0.001).

CONCLUSIONS

Following ACS treated with PCI, CR had a positive effect on major CVRFs, the degree of LVDD and exercise capacity and should be considered as effective tool to reduce morbidity in such patients.

Cardiac Rehabilitation in German Speaking Countries of Europe-Evidence-Based Guidelines from Germany, Austria and Switzerland LLKardReha-DACH-Part 2

Background: Scientific guidelines have been developed to update and harmonize exercise based cardiac rehabilitation (ebCR) in German speaking countries. Key recommendations for ebCR indications have recently been published in part 1 of this journal. The present part 2 updates the evidence with respect to contents and delivery of ebCR in clinical practice, focusing on exercise training (ET), psychological interventions (PI), patient education (PE). In addition, special patients’ groups and new developments, such as telemedical (Tele) or home-based ebCR, are discussed as well. Methods: Generation of evidence and search of literature have been described in part 1. Results: Well documented evidence confirms the prognostic significance of ET in patients with coronary artery disease. Positive clinical effects of ET are described in patients with congestive heart failure, heart valve surgery or intervention, adults with congenital heart disease, and peripheral arterial disease. Specific recommendations for risk stratification and adequate exercise prescription for continuous-, interval-, and strength training are given in detail. PI when added to ebCR did not show significant positive effects in general. There was a positive trend towards reduction in depressive symptoms for “distress management” and “lifestyle changes”. PE is able to increase patients’ knowledge and motivation, as well as behavior changes, regarding physical activity, dietary habits, and smoking cessation. The evidence for distinct ebCR programs in special patients’ groups is less clear. Studies on Tele-CR predominantly included low-risk patients. Hence, it is questionable, whether clinical results derived from studies in conventional ebCR may be transferred to Tele-CR. Conclusions: ET is the cornerstone of ebCR. Additional PI should be included, adjusted to the needs of the individual patient. PE is able to promote patients self-management, empowerment, and motivation. Diversity-sensitive structures should be established to interact with the needs of special patient groups and gender issues. Tele-CR should be further investigated as a valuable tool to implement ebCR more widely and effectively.

Exercise Intolerance in Heart Failure with Preserved Ejection Fraction

Exercise intolerance represents a typical feature of heart failure with preserved ejection fraction (HFpEF), and is associated with a poor quality of life, frequent hospitalizations, and increased all-cause mortality. The cardiopulmonary exercise test is the best method to quantify exercise intolerance, and allows detection of the main mechanism responsible for the exercise limitation, influencing treatment and prognosis. Exercise training programs improve exercise tolerance in HFpEF. However, studies are needed to identify appropriate type and duration. This article discusses the pathophysiology of exercise limitation in HFpEF, describes methods of determining exercise tolerance class, and evaluates prognostic implications and potential therapeutic strategies.

Pathophysiology of Exercise Intolerance and Its Treatment With Exercise-Based Cardiac Rehabilitation in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is the fastest growing form of heart failure in the United States. The cardinal feature of HFpEF is reduced exercise tolerance (peak oxygen uptake, (Equation is included in full-text article.)O2peak) secondary to impaired cardiac, vascular, and skeletal muscle function. There are currently no evidence-based drug therapies to improve clinical outcomes in patients with HFpEF. In contrast, exercise training is a proven effective intervention for improving (Equation is included in full-text article.)O2peak, aerobic endurance, and quality of life in HFpEF patients. This brief review discusses the pathophysiology of exercise intolerance and the role of exercise training to improve (Equation is included in full-text article.)O2peak in clinically stable HFpEF patients. It also discusses the mechanisms responsible for the exercise training-mediated improvements in (Equation is included in full-text article.)O2peak in HFpEF. Finally, it provides evidence-based exercise prescription guidelines for cardiac rehabilitation specialists to assist them with safely implementing exercise-based cardiac rehabilitation programs for HFpEF patients.

Effects of Exercise Training on Cardiac Function in Heart Failure with Preserved Ejection Fraction

Nearly half of patients with heart failure in the community have heart failure with preserved ejection fraction (HFpEF). Patients with HFpEF are often elderly and their primary chronic symptom is severe exercise intolerance. Left ventricular diastolic dysfunction is associated with the pathophysiology of HFpEF and is an important contributor to exercise intolerance in HFpEF patients. The effects of exercise training on left ventricular diastolic function in HFpEF patients have been examined in several randomised clinical trials. Meta-analysis of the trials indicates that exercise training can provide clinically relevant improvements in exercise capacity without significant change in left ventricular structure or function in HFpEF patients. Further studies are necessary to elucidate the exact mechanisms of exercise intolerance in HFpEF patients and to develop recommendations regarding the most effective type, intensity, frequency, and duration of training in this group.

Effects of exercise training on cardiac function, exercise capacity, and quality of life in heart failure with preserved ejection fraction: a meta-analysis of randomized controlled trials

Left ventricular (LV) diastolic dysfunction is associated with the pathophysiology of heart failure with preserved ejection fraction (HFpEF) and contributes importantly to exercise intolerance that results in a reduced quality of life (QOL) in HFpEF patients. Although the effects of exercise training on LV diastolic function, exercise capacity, or QOL in HFpEF patients have been examined in randomized clinical trials (RCTs), results are inconsistent due partly to limited power with small sample sizes. We aimed to conduct a meta-analysis of RCTs examining the effects of exercise training on LV diastolic function and exercise capacity as well as QOL in HFpEF patients. The search of electronic databases identified 8 RCTs with 436 patients. The duration of exercise training ranged from 12 to 24 weeks. In the pooled analysis, exercise training improved peak exercise oxygen uptake (weighted mean difference [95% CI], 1.660 [0.973, 2.348] ml/min/kg), 6-min walk distance (33.883 [12.384 55.381] m), and Minnesota Living With Heart Failure Questionnaire total score (9.059 [3.083, 15.035] point) compared with control. In contrast, exercise training did not significantly change early diastolic mitral annular velocity (weighted mean difference [95% CI], 0.317 [- 0.952, 1.587] cm/s), the ratio of early diastolic mitral inflow to annular velocities (- 1.203 [- 4.065, 1.658]), or LV ejection fraction (0.850 [- 0.128, 1.828] %) compared with control. In conclusion, the present meta-analysis suggests that exercise training improves exercise capacity and QOL without significant change in LV systolic or diastolic function in HFpEF patients.

High-intensity interval training is effective and superior to moderate continuous training in patients with heart failure with preserved ejection fraction: A randomized clinical trial

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a prevalent syndrome, with exercise intolerance being one of its hallmarks, contributing to worse quality of life and mortality. High-intensity interval training is an emerging training option, but its efficacy in HFpEF patients is still unknown.

DESIGN

Single-blinded randomized clinical trial.

METHODS

Single-blinded randomized clinical trial with exercise training 3 days per week for 12 weeks. HFpEF patients were randomly assigned to high-intensity interval training or moderate continuous training. At baseline and after 12 week follow-up, patients underwent clinical assessment, echocardiography and cardiopulmonary exercise testing (CPET).

RESULTS

Mean age was 60 ± 9 years and 63% were women. Both groups (N = 19) showed improved peak oxygen consumption (VO₂), but high-intensity interval training patients (n = 10) had a significantly higher increase, of 22%, compared with 11% in the moderate continuous training (n = 9) individuals (3.5 (3.1 to 4.0) vs. 1.9 (1.2 to 2.5) mL·kg^-1·min^-1, p < 0.001). Ventilatory efficiency and other CPET measures, as well as quality of life score, increased equally in the two groups. Left ventricular diastolic function also improved with training, reflected by a significant reduction in E/e' ratio by echocardiography (-2.6 (-4.3 to -1.0) vs. -2.2 (-3.6 to -0.9) for high-intensity interval training and moderate continuous training, respectively; p < 0.01). There were no exercise-related adverse events.

CONCLUSIONS

This randomized clinical trial provided evidence that high-intensity interval training is a potential exercise modality for HFpEF patients, being more effective than moderate continuous training in improving peak VO₂. However, the two strategies were equally effective in improving ventilatory efficiency and other CPET parameters, quality of life score and diastolic function after 3 months of training.

Heart failure with preserved ejection fraction: New approaches to diagnosis and management

The majority of older patients who develop heart failure (HF), particularly older women, have a preserved left ventricular ejection fraction (HFpEF). Patients with HFpEF have severe symptoms of exercise intolerance, poor quality-of-life, frequent hospitalizations, and increased mortality. The prevalence of HFpEF is increasing and its prognosis is worsening. However, despite its importance, our understanding of the pathophysiology of HFpEF is incomplete, and drug development has proved immensely challenging. Currently, there are no universally accepted therapies that alter the clinical course of HFpEF. Originally viewed as a disorder due solely to abnormalities in left ventricular (LV) diastolic function, our understanding has evolved such that HFpEF is now understood as a systemic syndrome, involving multiple organ systems, likely triggered by inflammation and with an important contribution of aging, lifestyle factors, genetic predisposition, and multiple-comorbidities, features that are typical of a geriatric syndrome. HFpEF is usually progressive due to complex mechanisms of systemic and cardiac adaptation that vary over time, particularly with aging. In this review, we examine evolving data regarding HFpEF that may help explain past challenges and provide future directions to care patients with this highly prevalent, heterogeneous clinical syndrome.

Therapy for heart failure with preserved ejection fraction: current status, unique challenges, and future directions

Heart failure (HF) with preserved ejection fraction (HFpEF) is the most common form of HF. Among elderly women, HFpEF comprises more than 80% of incident HF cases. Adverse outcomes-exercise intolerance, poor quality of life, frequent hospitalizations, and reduced survival-approach those of classic HF with reduced EF (HFrEF). However, despite its importance, our understanding of the pathophysiology of HFpEF is incomplete, and despite intensive efforts, optimal therapy remains uncertain, as most trials to date have been negative. This is in stark contrast to management of HFrEF, where dozens of positive trials have established a broad array of effective, guidelines-based therapies that definitively improve a range of clinically meaningful outcomes. In addition to providing an overview of current management status, we examine evolving data that may help explain this paradox, overcome past challenges, provide a roadmap for future success, and that underpin a wave of new trials that will test novel approaches based on these insights.