Smartphones 'ideal' for atrial fibrillation community screening
Results of a recent study presented last week at the 2012 American Heart Association (AHA) Scientific Sessions conference in Los Angeles show that a high quality single-lead ECG can be rapidly and simply recorded using an iPhone app to accurately diagnose atrial fibrillation (AF), the most common sustained arrhythmia which carries a five-fold increased risk of stroke.
Until now, community ECG screening has not been considered a feasible approach for AF detection. However, the study indicates that the mobile device could be an ideal tool for community screening programs to detect the disease, thereby reducing ischemic stroke related to previously undiagnosed AF.
"At last, we have an effective and simple way to do community ECG screening for unknown atrial fibrillation, with the real potential to reduce the stroke burden," Ben Freedman, the study's principal investigator and cardiologist at Concord Hospital in Australia, said in a Nov. 7 announcement.
Researchers tested the AliveCor Heart Monitor app running on an iPhone that allows for wireless recordings of rhythm strips of any duration, which are stored on the device and securely in the cloud for later analysis. The ECG data is sent wirelessly to the iPhone from the heart monitor via AliveCor's low-power, proprietary communication protocol and requires no pairing between the iPhone and the heart monitor.
The study included 109 patients (70 sinus rhythm and 39 AF) who had single-lead ECGs recorded with the AliveCor Heart Monitor before a 12-lead ECG had been performed, in order to develop the optimized algorithm. The AF diagnosis was then validated in another 204 patients (48 AF). The results presented during the AHA session were statistically significant with accuracy rates of 94 percent and 95 percent for the two cardiologists interpreting the raw trace, and 97 percent for the automated algorithm, which was optimized to enhance sensitivity (sensitivity 98 percent, specificity 97 percent).
The AliveCor Heart Monitor is awaiting 510(k) clearance from the U.S. Food and Drug Administration, and is compatible with the iPhone 4 and 4S. The app enables patients to monitor their heart health anywhere, at any time, and provides physicians with an additional heart health assessment tool.