The Differences in Cardiac Rehabilitation Outcomes by Age in Myocardial Infarction: A Preliminary Study

OBJECTIVE: To determine the age-related changes in cardiac rehabilitation (CR) outcomes, which includes hemodynamic and metabolic factors, in patients with myocardial infarction (MI). METHODS: CR was administered for 8 weeks to 32 men (mean age, 54.0±8.8 years) who underwent percutaneous coronary intervention for acute MI between July 2012 and January 2016. The exercise tolerance tests were performed before and after the CR. The results were stratified based on a cut-off age of 55 years. RESULTS: In the whole patient group, the hemodynamic variables such as the resting heart rate (HR(rest)), systolic blood pressure (SBP(rest)), submaximal HR (HR(submax)), SBP (SBP(submax)), and rate pressure product (RPP(submax)) significantly decreased and the maximal HR (HR(max)) and RPP (RPP(max)) significantly increased. All metabolic variables displayed significant improvement, to include maximal oxygen consumption (VO(2max)) and ventilation (V(Emax)), anaerobic threshold (AT), and the maximal oxygen pulse (O(2pulsemax)). However, upon stratification by age, those who were younger than 55 years of age exhibited significant changes only in the HR(rest) and RPP(submax) and those aged 55 years old or greater displayed significant changes in all hemodynamic variables except diastolic BP. Both groups displayed significant increases in the VO(2max), VE(max), and AT; the older group also exhibited a significant increase in O(2pulsemax). The magnitude of the changes in the hemodynamic and metabolic variables before and after CR, based on age, did not differ between the groups; although, it tended to be greater among the older participants of this study's sample. CONCLUSION: Because the older participants tended to show greater hemodynamic and metabolic changes due to CR, a more aggressive CR program must be administered to elderly patients with MI.