Early-phase Exercise-based Cardiac Rehabilitation After MI

Myocardial infarction (MI) is not only a severe form of coronary heart disease but also a leading cause of death and physical disability, particularly in the rapidly growing elderly population. Although percutaneous coronary interventions reduce mortality, ensuring the recovery and reintegration of discharged patients into society remains an unresolved issue. Cardiac rehabilitation (CR) is beneficial for patients with MI in terms of reducing cardiovascular mortality and hospital readmissions, managing cardiovascular risk factors, and improving aerobic capacity. CR is a comprehensive intervention tailored to the individual needs of patients diagnosed with heart disease. It includes personalized exercise training, physical activity promotion, health education, cardiovascular risk management, and psychological support. Initial recommendations for CR were limited to low-risk patients following MI. However, over the past two decades, with the accumulation of evidence supporting the benefits of CR, current clinical guidelines now routinely recommend comprehensive CR for a broader range of cardiac diagnoses, including acute coronary syndrome and heart failure with reduced ejection fraction. Until two decades ago, studies recommended starting CR in the early phase, defined as the second-week post-discharge. However, in the past decade, CR initiation with very low-intensity exercise activity as early as one week after MI onset has been reported as safe and effective. More recently, studies have shown the beneficial effects of terminating bed rest within 12-24 hours and initiating bedside activities. Phase I exercise-based CR has been shown to be effective in improving exercise capacity and preventing recurrent cardiac events. Nonetheless, concerns remain regarding early exercise-based CR due to exercise-induced ischemia after acute MI. While the effects of early rehabilitation initiated post-MI have been investigated in the literature, sufficient evidence has yet to be established.