Asynchronous cardiac telerehabilitation with gamification improves exercise capacity in chronic coronary syndrome: interim results from a randomized controlled trial

Background Cardiac telerehabilitation (CTR) has gained attention in recent years, but few studies have evaluated it as phase II cardiac rehabilitation (CR) for chronic coronary syndrome (CCS). Objective This interim report demonstrates that asynchronous CTR is effective compared to conventional asynchronous CR. Methods Consecutive cases admitted to CCS after November 2024 were randomly assigned to either asynchronous CTR using smartphones/smartwatches (intervention group) or standard asynchronous CR following physician and physiotherapist advice (control group) after discharge. Both groups could concurrently undergo synchronous CR, with an observation period of 150±30 days. The smartphone app measured and managed exercise heart rate (HR) via smartwatch. Using gamification features, patients earned points (up to 120 points) for achieving exercise within the appropriate HR range and received weekly feedback based on points. The primary outcome measure was the change in 6-minute walk distance (6MWD) from baseline. Secondary outcome measures included changes in BMI, blood tests (LDL-cholesterol, HbA1c, estimated glomerular filtration rate, NT-proBNP), health-related QoL questionnaire scores, and a visual analogue scale (VAS) (0–100, higher scores indicating greater perceived hassle) measuring perceived hassle toward exercise therapy. Results By November 2025, 173 patients met the inclusion criteria, and 91 declined to participate in the study. Consequently, 82 patients were enrolled, with 37 completing the protocol and included in this analysis (6 dropped out). The mean intervention period was 150 ± 9 days. Baseline characteristics are shown in Table 1, with no significant differences between groups. The primary outcome, the increase in 6MWD, was significantly longer in the intervention group than in the control group. For the secondary outcomes, no significant changes were observed except for the estimated glomerular filtration rate (Table 2). The total smartphone app usage rate in the intervention group was 50.0% (1272/2546 days). The change in 6MWD did not show a significant correlation with app usage rate (r = 0.366, p = 0.233), but a significant correlation was observed with the appropriate exercise rate (the number of days achieving "120 points" divided by the number of days the app was used) (r = 0.533, p = 0.027). One patient in the control group was hospitalised for a period due to worsening heart failure. Conclusion Asynchronous CTR in phase II using a smartphone app with gamification features is effective for improving exercise tolerance in CCS patients.