Effects of cardiac rehabilitation on frail patients with cardiac conditions: A systematic review

Cardiac rehabilitation (CR) is a comprehensive management well acknowledged as a secondary prevention for cardiac conditions. Though previous studies showed its beneficial effects, the participation rate was reportedly low, indicating that additional factors may be present affecting effects and adherence of CR. Frailty is a progressive condition manifested as reduction in physiological capacity and reserve, as well as vulnerability to stressors. Frailty is highly prevalent in patients with cardiac diseases as well as those undergoing cardiac surgeries and procedures, affecting outcomes from CR. It has been recommended that patients attend all sessions of CR program to acquire maximum treatment effects. However, completion of CR program may be harder for frailer patients. Assessment of frailty levels may empower frontline staff to determine whether the patients will be more likely to no adhere to CR and need additional support. At present, the effects of CR on general and specific domains in frail patients with cardiac conditions remains unclear. In addition, standardized CR strategy for this vulnerable cohort is lacking. This project evaluated clinical studies assessing effects of CR with various components, intensities and durations in frail patients, aiming to provide valuable information on prediction of potential response and strategy making for these patients in clinical practice.