Effect of Aerobic Training on Heart Rate Recovery in Patients with Established Heart Disease; a Systematic Review

BACKGROUND: Although a delayed decrease in heart rate during the first minute after graded exercise has been identified as a powerful predictor of overall mortality in cardiac patients, the potential to influence this risk factor by aerobic training remains to be proven. OBJECTIVE: The aim was to study the relationship between aerobic training and Heart Rate Recovery (HRR) in patients with established heart disease. METHODS: (Quasi) randomized clinical trials on aerobic exercise training in adults with established heart disease were identified through electronic database and reference screening. Two reviewers extracted data and assessed the risk of bias and therapeutic validity. Methodological validity was evaluated using an adapted version of the Cochrane Collaboration's tool for assessing risk of bias and the therapeutic validity of the interventions was assessed with a nine-itemed, expert-based rating scale (CONTENT). Scores range from 0 to 9 (score ≥ 6 reflecting therapeutic validity). RESULTS: Of the 384 articles retrieved, 8 studies (449 patients) were included. Three of the included studies demonstrated adequate therapeutic validity and five demonstrated low risk of bias. Two studies showed both adequate therapeutic validity and a low risk of bias. For cardiac patients aerobic exercise training was associated with more improvement in HRR compared to usual care. CONCLUSION: The present systematic review shows a level 1A evidence that aerobic training increases HRR in patients with established heart disease.