Feasibility of a smartphone app for prescribed exercise tutoring in patients with stable coronary heart disease.

Background: Digital health technologies have potential to address the challenges associated with traditional cardiac rehabilitation (CR). However, it is not complete enough for prescribed exercise guidance and remote monitoring. Objective: We aimed to evaluate the feasibility of a smartphone app for prescribed exercise tutoring by exercise videos combined with wearable devices to monitor heart rate in patients with stable coronary heart disease (CHD). Methods: The study is a quasi-experimental design study with a single group. A total of 31 patients were included with an average age of 56.2 years (SD 13.4). They participated in a 12-week remote digital CR program. We employed a wearable heart rate monitoring device connected with an app to monitor the patients' exercise intensity. The app can display the videos corresponding to an exercise prescription to guide the exercise. Cardiorespiratory endurance, blood pressure, blood glucose, cholesterol, blood uric acid, left ventricular ejection fraction and quality of life (QoL) were assessed at the beginning and end of the intervention. Compliance and safety events were recorded as well. Results: Completion rate reached 90.3%. Average daily effective exercise time was 39.4 min (SD 17.8), and 92.9% of the patients could exercise in the prescribed intensity for at least 20 min per day. Average effective exercise days per week were 4.6 days (SD 2.2), and 67.9% of the patients could exercise in the prescribed intensity for at least 3 days per week. Patients' peak VO2 (P = 0.041) and peak metabolic equivalents (P = 0.018) were significantly increased, low-density lipoprotein (P = 0.036) and diastolic blood pressure at rest (P = 0.044) were significantly decreased, and depression (GAD-7, P = 0.014) and anxiety (PHQ-9, P = 0.013) were significantly improved. Conclusions: It is feasible, safe, and helpful for stable CHD patients to use the app for prescribed exercise tutoring with videos combined with wearable devices to monitor heart rate. Trial Registration: ChiCTR1800019144.