Mobile phone-based surveillance of cardiac patients at home.

We tested the reliability, acceptability and feasibility of a home-monitoring system for cardiac patients. Each participant was equipped with a mobile phone, an automatic blood pressure device and a digital weight scale. In total, 20 patients (14 patients with chronic heart failure, six patients with hypertension; mean age 50 years, standard deviation [SD] 14) were monitored for 90 days each. They were asked to measure their blood pressure, pulse and body weight every day, and to transfer the data together with the dosage of medication to the telemonitoring server using wireless Internet technology in the mobile phone. The physician in charge received email alerts when reported data fell outside pre-defined limits. The patients' compliance with the system was high. During a cumulative monitoring period of 1,735 days, there were 2,040 data transfer sessions, a mean of 102 per patient (SD 43). The mean percentage of successful data transfers was 83% (SD 22). The stability of the telemonitoring system was 98%, meaning that patient data transfer was almost always possible. The accessibility of the secure web server for physicians was above 99%. The web-based home-monitoring system was reliable and easy to handle for both patients and health care professionals. It may be a useful tool for patients with heart failure as well as hypertensive patients.