Kardia - A Smartphone-based Care Model for Outpatient Cardiac Rehabilitation

Cardiovascular disease (CVD) is the most common cause of death in Singapore, accounting for ~34% of deaths. This means 1 in every 3 deaths in Singapore is due to heart disease or stroke. Ischemic heart disease is the leading cause of mortality and accounts for 17% of all deaths attributable to life-style related risk-factors. The total burden of this disease is likely to increase given the aging population and the increase in prevalence of obesity and predisposing conditions such as diabetes mellitus, hypertension and hyperlipidaemia.

A number of modifiable environmental and patient specific factors increase the chance of developing coronary artery disease. These include smoking, high blood cholesterol, physical inactivity, diabetes, high blood pressure and obesity. Following myocardial infarction, acute coronary syndromes, surgical and percutaneous interventions, cardiac rehabilitation has provided an avenue for reducing future cardiovascular risks in patients by positively influencing these factors. The eventual goal of the program is to engage patients with permanent behavioural and life-style changes. There is strong evidence for the effectiveness of cardiac rehabilitation which is given a Class 1 recommendation from the American/European Cardiology guidelines, particularly for post-myocardial infarction patients. Several studies and meta-analyses have demonstrated a significant reduction in mortality and morbidity.

Despite the clear benefits of cardiac rehabilitation programs, the uptake of these programs has been poor due to various patient and system factors. Cardiac rehabilitation programs are traditionally carried out in hospitals and health centres under the direct personal supervision of mentoring clinicians. Patient barriers, such as time constraints and distance from treatment centres lead to poor uptake of programs among eligible patients. To overcome these barriers, home-based care models have been proposed as a viable alternative to hospital-based cardiac rehabilitation programs even in the 1980s. The current state of mobile phone communication and technology provides not only the capacity but an especially attractive media option to support home-based cardiac rehabilitation programs.

This study aims to investigate a smartphone-based cardiac rehabilitation program for patients recovering from myocardial infarction. The program focuses on providing patient centric self-monitoring platform enabling patients to take control and be actively involved in their medical care. The program ("Kardia") is a 6-week rehabilitation program enabling patients to track their blood pressure, physical activity and medicine compliance through a mobile application. Each patient in the intervention arm is provided with a blood pressure monitor and activity tracker. The data from these devices would be automatically synced by a mobile application and uploaded to a confidential web portal which is only accessible by physician care-givers. The application also provides educational content/tasks, appropriate reminders for taking medications and daily goals on activity targets set by the care provider. This would help to engage the patients to enable behavioural change and improve compliance to mediation and activity recommendations.

In Changi General Hospital, the uptake of cardiac rehabilitation among eligible patients is less than 20%. This study hopes to target the remaining 80% of patients who have refused the traditional cardiac rehabilitation program. It will be the first time that a smartphone based home cardiac rehabilitation program would be offered in Singapore. If shown to be safe and feasible, "Kardia" will help to improve patient outcomes in short to medium term. In addition, it may empower the patients to take a more active role in their medical care and promote long lasting behavioural changes in the long term. There will also be a significant operation impact if "Kardia" can be rolled out as an alternative care model to the traditional centre-based cardiac rehabilitation program, enabling greater patient access to "cardiac rehabilitation". This is also in line with national initiatives to promote an active and healthy lifestyle, i.e. National Steps Challenge by the Health Promotion Board.

The project is a randomized controlled study of smartphone based cardiac rehabilitation program compared to routine care in patients who did not sign up for traditional hospital-based cardiac rehabilitation. 50 patients who are randomized to the intervention group (mHealth) will be enabled with remote monitoring devices (Blood Pressure and wearable vital signs monitor, Biovotion) and "Kardia" mobile application, for home-based rehabilitation program followed by review in the outpatient Cardiology clinics. The control group (50 patients) will just be monitored at fixed intervals in the outpatient Cardiology clinics.

Patients will be advised to commence the exercise program 2 weeks after the myocardial infarction

Time Exercise Intensity Exercise Frequency/Duration Patient actions Week 1 light 3x/week; 10 minutes Exercise diary Week 2 light 3x/week; 20 minutes Week 3 light 3x/week; 30 minutes Week 4 moderate 3x/week; 15 minutes Week 5 moderate 3x/week; 30 minutes Week 6 moderate 4x/week; 30 minutes Week 7 moderate 5x/week; 30 minutes Week 8 moderate 5x/week; 30 minutes