Exercise and Sports Science Australia position statement on exercise training and chronic heart failure

Chronic heart failure (CHF) is a complex syndrome characterised by progressive decline in left ventricular function, low exercise tolerance and raised mortality and morbidity. Regular exercise participation has been shown to be a safe and effective treatment modality in the majority of CHF patients, partially reversing some of the maladaptations evident in myocardial and skeletal muscle function, and resulting in improvements in physical fitness and quality of life, and perhaps reduced mortality. The volume and intensity of exercise that is recommended depends on the syndrome severity, however in most patients it should consist of a combination of low-to-moderate intensity aerobic (endurance) exercise on most days of the week and individually prescribed low-to-moderate intensity resistance (strength) training at least twice per week. Additionally, all patients should be closely monitored prior to and during exercise for contraindications by an appropriately trained health professional. The purpose of this statement is to inform and guide exercise practitioners and health professionals in the safe and effective prescription and supervision of exercise for patients with CHF.

Circuit resistance training in chronic heart failure improves skeletal muscle mitochondrial ATP production rate—A randomized controlled trial

Background : We aimed to determine the role of skeletal muscle mitochondrial ATP production rate (MAPR) in relation to exercise tolerance after resistance training (RT) in chronic heart failure (CHF).

Methods and Results : Thirteen CHF patients (New York Heart Association functional class 2.3 ± 0.5; Left ventricular ejection fraction 26 ± 8%; age 70 ± 8 years) underwent testing for peak total body oxygen consumption (VO_2peak), and resting vastus lateralis muscle biopsy. Patients were then randomly allocated to 11 weeks of RT (n = 7), or continuance of usual care (C; n = 6), after which testing was repeated. Muscle samples were analyzed for MAPR, metabolic enzyme activity, and capillary density. VO_2peak and MAPR in the presence of the pyruvate and malate (P+M) substrate combination, representing carbohydrate metabolism, increased in RT (P < .05) and decreased in C (P < .05), with a significant difference between groups (VO_2peak, P = .005; MAPR, P = .03). There was a strong correlation between the change in MAPR and the change in peak total body oxygen consumption (VO_2peak) over the study (r = 0.875; P < .0001), the change in MAPR accounting for 70% of the change in VO_2peak.

Conclusions : These findings suggest that mitochondrial ATP production is a major determinant of aerobic capacity in CHF patients and can be favorably altered by muscle strengthening exercise.

Respiratory muscle dysfunction and training in chronic heart failure

A characteristic feature of chronic heart failure (CHF) is reduced exercise tolerance. Several factors contributing to this have been identified, including alterations in central haemodynamics, skeletal muscle oxygen utilisation and respiratory muscle dysfunction. This review focuses on abnormalities identified in respiratory muscle structure and function in CHF and recent evidence for the benefit of selective inspiratory muscle training in CHF. Included in this review are findings from original investigations, with a specific focus on recent published data.

Complexity of management and health outcomes in a prospective cohort study of 573 heart failure patients in Australia : does more equal less?

Aims and objectives : To compare the efficacy of chronic heart failure management programmes (CHF-MPs) according to a scoring algorithm used to quantify the level of applied interventions–the Heart Failure Intervention Score (HF-IS).

Background : The overall efficacy of heart failure programmes has been proven in several meta-analyses. However, the debate continues as to which components are essential in a heart failure programme to improve patient outcomes.

Design : Prospective cohort study of patients participating in heart failure programmes.

Method : Forty-eight of 62 (77%) programmes in Australia participating in a national register of CHF-MPs were evaluated using the HF-IS: derived from a summed and weighted score of each intervention applied by the CHF-MP (27 interventions overall). The CHF-MPs were prospectively categorised as relatively low (HF-IS < 190 – n = 39 programmes & 407 patients) or high (HF-IS ≥ 190 – n = 9 programmes & 166 patients) in complexity. Six-month morbidity and mortality rates in 573 consecutively recruited patients with systolic dysfunction and in New York Heart Association Class II–IV were prospectively examined.

Results : Patients exposed to CHF-MPs with a high HF-IS had a lower rate of unplanned, all-cause hospitalisation (n = 24, 14% vs. n = 102, 25%) compared with CHF-MPs with a low HF-IS within six months. On an adjusted basis, CHF-MPs with a high HF-IS were associated with a reduced risk of unplanned hospitalisation and/or death within six months and remained event-free longer.

Conclusion : High complexity CHF-MPs applying more evidence-based interventions are associated with a higher event-free survival over six months.

Relevance to clinical practice : The HF-IS is an easy-to-use evidence-based tool to assist programme coordinators to improve the quality of their heart failure programme which may also improve patient outcomes.

Evidence-based chronic heart-failure management programs : myth or reality?

Background Chronic heart-failure management programmes (CHF-MPs) have become part of standard care for patients with chronic heart failure (CHF). Objective To investigate whether programmes had applied evidence-based expert clinical guidelines to optimise patient outcomes. Design A prospective cross-sectional survey was used to conduct a national audit. Setting Community setting of CHF-MPs for patients postdischarge. Sample All CHF-MPs operating during 2005–2006 (n=55). Also 10–50 consecutive patients from 48 programmes were recruited (n=1157). Main outcome measures (1) Characteristics and interventions used within each CHF-MP; and (2) characteristics of patients enrolled into these programmes. Results Overall, there was a disproportionate distribution of CHF-MPs across Australia. Only 6.3% of hospitals nationally provided a CHF-MP. A total of 8000 postdischarge CHF patients (median: 126; IQR: 26–260) were managed via CHF-MPs, representing only 20% of the potential national case load. Significantly, 16% of the caseload comprised patients in functional New York Heart Association Class I with no evidence of these patients having had previous echocardiography to confirm a diagnosis of CHF. Heterogeneity of CHF-MPs in applied models of care was evident, with 70% of CHF-MPs offering a hybrid model (a combination of heart-failure outpatient clinics and home visits), 20% conducting home visits and 16% conducting an extended rehabilitation model of care. Less than half (44%) allowed heart-failure nurses to titrate medications. The main medications that were titrated in these programmes were diuretics (n=23, 96%), β-blockers (n=17, 71%), ACE inhibitors (ACEIs) (n=14, 58%) and spironolactone (n=9, 38%). Conclusion CHF-MPs are being implemented rapidly throughout Australia. However, many of these programmes do not adhere to expert clinical guidelines for the management of patients with CHF. This poor translation of evidence into practice highlights the inconsistency and questions the quality of health-related outcomes for these patients.