Objective: The aim of this study was to examine physical and heart rhythm management device malfunction complications after participating in a cardiac rehabilitation program intervention compared with usual care. Method: This study was a clinical trial of 100 patients. After randomization, intervention group patients received 8 cardiac rehabilitation program sessions for 8 weeks and follow-up phone calls. Each session consisted of exercise training, education, and psychological interventions. Data were collected at 3 points in both groups-baseline and 8 and 12 weeks after the first day of the intervention-using a researcher-designed case report form. Data were analyzed using descriptive and nonparametric tests. Results: Of the participants, 59% were men, and the sample was aged 40 to 60 years. At the 8- to 12-week follow-up, there were less physical complications among the cardiac rehabilitation group (P < .001) and no between-group differences in complications related to device malfunction. By heart rhythm device type, cardiac rehabilitation had the greatest efficacy in reducing physical complications in patients with cardioverter/defibrillators. Conclusions: Cardiac rehabilitation reduced physical complications in patients with cardiac rhythm management devices, especially in patients with cardioverter/defibrillators. Cardiac clinical nurse specialists should recommend rehabilitation programs as part of postimplantation rhythm device treatment to decrease the risk of physical complications.