EXERCISE REHABILITATION IN PATIENTS WITH
CONGESTIVE HEART FAILURE-A SYSTEMATIC REVIEW OF THE LITERATURE D.O'Connell JM Lowe*, P. Candlish, A Wilkinson J.Silberberg &
K.Inder Division of
Medicine John Hunter Hospital and Discipline of Clinical Pharmacology, Faculty
of Medicine and Health Sciences, University of Newcastle, NSW Chronic
(congestive) heart failure (CHF) is the only common cardiovascular condition
increasing in incidence and prevalence. Traditional teaching advocated rest,
but since the 1980's reports have suggested that physical training could
increase exercise capacity and otherwise benefit patients with CHF. A
systematic review was undertaken as existing narrative reviews had not
attempted to identify all existing studies nor to pool data across studies. Aims: 1) To identify all published studies.2) To assess their quality. 3)
To synthesise the results of these studies using meta-analytic techniques if
appropriate. 4) to formulate recommendations about the role of exercise in the
management of CHF and the need for further research. Methods: The review was undertaken using the standard methodology for
systematic reviews established by the Cochrane Collaboration and modified to
include studies other than randomised controlled trials. Results: The various search strategies identified 3385 potential studies,
of which 1553 were duplicates. After review, 23 randomised controlled trials
(RCT's), 4, non-randomised controlled trials, 12 cross-over studies and 19 case
series were identified for data extraction. In general the study quality was
disappointing. Data was extracted on the most commonly reported physiological
variable, oxygen consumption, and patient relevant variables such as exercise
tolerance, dyspnoea scale, quality of life, mortality and hospital readmission.
Pooled data on oxygen consumption showed a statistically significant difference
in favour of exercise training at 2, 3, and 6 months (weighted mean difference
at 6 months 2.74,95% CI 1.53-3.95 ml/kg/min). Data on exercise capacity extracted
from 10 studies showed an improvement in the intervention group in all studies
which was statistically significant in 8, and the weighted mean differences
were statistically different from zero at all follow-up times. There appeared
to be a "dose response" with the treatment effect increasing with the duration
of exercise training.(weighted mean difference at 4 weeks 1.86,95%CI0.37-3.35;
at 6 months 3.52,95% CI 1.72-5.33). Improvement in quality of life was less
clear, and data on clinical outcomes was sparse, and no conclusions can be
drawn. Conclusions: This review provides no evidence that exercise is harmful and is
consistent with the hypothesis that exercise training may increase exercise
tolerance and duration in a clinically useful way. However little data is
available on clinical outcomes and the costs of widespread implementation needs
investigation.
