Exercise rehabilitation in chronic heart failure

Acceptability, Feasibility and Preliminary Evaluation of a Novel, Personalised, Home-Based Physical Activity Intervention for Chronic Heart Failure (Active-at-Home-HF): a Pilot Study

Purpose

Less than 10% of heart failure patients in the UK participate in cardiac rehabilitation programmes. The present pilot study evaluated feasibility, acceptability and physiological effects of a novel, personalised, home-based physical activity intervention in chronic heart failure.

Methods

Twenty patients (68 ± 7 years old, 20% females) with stable chronic heart failure due to reduced left ventricular ejection fraction (31 ± 8 %) participated in a single-group, pilot study assessing the feasibility and acceptability of a 12-week personalised home-based physical activity intervention aiming to increase daily number of steps by 2000 from baseline (Active-at-Home-HF). Patients completed cardiopulmonary exercise testing with non-invasive gas exchange and haemodynamic measurements and quality of life questionnaire pre- and post-intervention. Patients were supported weekly via telephone and average weekly step count data collected using pedometers.

Results

Forty-three patients were screened and 20 recruited into the study. Seventeen patients (85%) completed the intervention, and 15 (75%) achieved the target step count. Average step count per day increased significantly from baseline to 3 weeks by 2546 (5108 ± 3064 to 7654 ± 3849, P = 0.03, n = 17) and was maintained until week 12 (9022 ± 3942). Following completion of the intervention, no adverse events were recorded and quality of life improved by 4 points (26 ± 18 vs. 22 ± 19). Peak exercise stroke volume increased by 19% (127 ± 34 vs. 151 ± 34 m/beat, P = 0.05), while cardiac index increased by 12% (6.8 ± 1.5 vs. 7.6 ± 2.0 L/min/m², P = 0.19). Workload and oxygen consumption at anaerobic threshold also increased by 16% (49 ± 16 vs. 59 ± 14 watts, P = 0.01) and 10% (11.5 ± 2.9 vs. 12.8 ± 2.2 ml/kg/min, P = 0.39).

Conclusion

The Active-at-Home-HF intervention is feasible, acceptable and effective for increasing physical activity in CHF. It may lead to improvements in quality of life, exercise tolerance and haemodynamic function.

Trial Registration

www.clinicaltrials.gov NCT0367727. Retrospectively registered on 17 September 2018.

Behavioral intervention, nutrition, and exercise trials in heart failure

With the aging of the population and advances in acute treatment of ischemic events and surgical techniques for coronary artery and valvular heart disease, the prevalence of heart failure has been increasing. Lifestyle modifications are an integral part of preventing and treating most pathologic human conditions, and include behavioral modifications, diet, and exercise. Despite advances in medical and device therapy for heart failure, clinicians still hope that patients will adhere to nonpharmacologic interventions, some of which can actually improve symptoms and quality of life. This article reviews the role of these lifestyle modifications in preventing and treating heart failure.

The role of exercise on L-arginine nitric oxide pathway in chronic heart failure

Chronic heart failure (CHF) is a pathological state with high morbidity and mortality and the full understanding of its genesis remain to be elucidated. In this syndrome, a cascade of neurohormonal and hemodynamic mechanisms, as well as inflammatory mediators, are activated to improve the impaired cardiac function. Clinical and experimental observations have shown that CHF is associated with a generalized disturbance in endothelium-dependent vasodilation, which may contribute to the progression of ventricular and vascular remodelling in this syndrome. There is also accumulating evidence that disturbances in nitric oxide (NO) availability is involved in the development of heart failure at the systemic and cardiac levels. NO is a ubiquitous signalling molecule which causes potent vasodilation, inhibits platelet activation and regulates the contractile properties of cardiac myocytes. It is generated from the amino acid L-arginine via constitutive and inducible isoforms of the enzyme NO synthase (NOS). There is evidence that exercise, a nonpharmacological tool, improves symptoms, fitness (VO_2peak), quality of life and NO bioavailability in CHF population. This review examines different aspects of the L-arginine-NO pathway and inflammation in the physiopathology of CHF and highlights the important beneficial effects of exercise in this disease.

Upper-Extremity Exercise Training in Heart Failure

PURPOSE

Aerobic exercise training (ExTR), predominantly performed with lower extremities, has been used to reverse heart failure (HF)-related exercise intolerance. The present study determined the safety and efficacy of upper-extremity exercise in HF subjects because daily activities are performed using both upper and lower extremities and there is little cross-training effects between extremities.

METHODS

Seven subjects underwent 36 sessions (40 minutes, 3 times per week for 12 weeks) of upper-extremity ExTR (ARM ExTR) using arm ergometers, the arm function of a NuStep device, and an Airdyne stationary cycle. Exercise intensity and duration during weeks 1 to 4 were gradually increased to achieve a 75% to 85% peak heart rate. Pre- and post-ExTR tests included arm ergometer cardiopulmonary testing with echocardiography and quality of life self-administered surveys.

RESULTS

After ARM ExTR test duration increased by 22% (P = .008), respiratory exchange ratio increased by 10% (P = .02), whereas peak oxygen consumption was not improved. Echocardiographic parameters were not altered by ARM ExTR. The total scores of both the Minnesota Living With Heart Failure Questionnaire (P = .02) and the Medical Outcomes Study-36 questionnaire (P = .05) were improved, but the Functional Status Questionnaire scores were not improved.

CONCLUSIONS

Although this study was limited in the number of subjects and lacked a control group, results indicate that ARM ExTR is safe and well-tolerated by persons diagnosed with HF, a finding that is relevant for individuals with HF who cannot exercise with lower extremities.