Effect of exercise training on heart rate recovery in patients post anterior myocardial infarction

Background: Regular exercise training has been shown to reduce mortality, improve functional capacity; and control the risk factors in myocardial infarction (MI) patients. Heart rate recovery (HRR) is a strong independent mortality predictor in patients with previous MI. Aim: The main objective of this study was to investigate the impact of exercise training on heart rate recovery in patients post anterior myocardial infarction. Methods: We recruited patients one month after having anterior MI who were referred to cardiac rehabilitation (CR) clinic in Ain Shams University hospital between October 2016 and July 2017. All the patients participated in exercise training sessions 3 times a week for 12 weeks. Symptom limited treadmill exercise test was done before and after exercise training program to calculate heart rate recovery in 1st minute (HRR1) and 2nd minute (HRR2). Results: A total of 50 patients, including 44 (88%) males, completed the exercise training program. The mean age was 51 years. Statistically significant improvement in HRR1 and HRR2 was observed (p value <0.001) after completion of exercise based cardiac rehabilitation program. Significant improvement in resting heart rate was also observed (p value <0.001). Moreover, metabolic equivalent (METs) and HR reserve were improved significantly (p value <0.001). No statistically significant changes were observed in resting systolic and diastolic blood pressures and maximum HR (p value = 0.95, 0.76 and 0.31 respectively). Conclusion: Exercise training improves HRR, resting HR, METs and HR reserve in post anterior MI patients.