Image: A smartphone app can noninvasively detect AF (Photo courtesy of Hanna Oksanen/ UTU).
A new app uses the accelerometers and gyroscopes integrated into modern smartphones in order to detect cardiac activity and identify atrial fibrillation (AF).
Developed at the University of Turku (UTU; Finland) and Turku University Hospital (Finland), the smartphone mechanocardiography app uses the integrated accelerometer to detect three-dimensional (3D) linear motion, and the integrated gyroscope to detect 3D rotational motion along three axes. The app then uses proprietary algorithms to analyze the micromovements in the chest and reliably determine AF.
In a blind study conducted to validate the smartphone app, the researchers compared it to visual interpretation of telemetry electrocardiographic (ECG) recordings in 300 hospitalized patients. The results showed 96% accuracy in AF identification. According to the researchers, the results are also significant in that the study group included different kinds of patients, some of whom had heart failure (HF), coronary artery disease (CAD), and ventricular extrasystole at the same time. The study was published on March 11, 2018, in Circulation.
“This is the first time that ordinary consumer electronics have achieved such reliable results that they can be actually beneficial for the patient's medical care. The results are also remarkable in that intermittent atrial fibrillation is not always detected even at the doctor's office,” said senior author Professor Juhani Airaksinen, MD, of Turku University Hospital. “If everyone can measure with an ordinary smart phone whether they have atrial fibrillation, we have the possibility to direct patients straight to the doctor and further testing without any delay. Therefore, the potential for economic savings is significant.”
AF occurs when the heart's two upper chambers beat erratically. In one form, paroxysmal AF, patients have bouts of erratic beats that begin spontaneously and usually last less than a week. AF can lead to serious adverse events such as thrombi traveling from the heart to obstruct arteries supplying the brain, causing stroke, or other parts of the body causing tissue damage.
University of Turku
Turku University Hospital