Smartphone device detects atrial fibrillation
October 3, 2014
The Food and Drug Administration cleared an algorithm for use by patients on a device that attaches to a smartphone to screen for atrial fibrillation instantly.
The AliveCor Heart Monitor attaches to the back of iPhones or Android-based smartphones. Users place fingers on the device and see information on the phone’s screen. They can log their symptoms, and the ECG reading is sent to the company’s server, so data can be accessed later.
The FDA approved the AliveCor Heart Monitor in 2013, and patients have used it since March 2014, with the device sending the ECG reading to a cardiologist or cardiac technician who would send a reply within 24 hours. In August 2014, the FDA cleared an algorithm to be used in a new, free app on the device that allows patients to get an immediate result showing whether or not they are likely to have atrial fibrillation. The company launched the app on the marketplace at the Health 2.0 fall conference in Santa Clara, Calif.
Validation trials have shown that the single-lead AliveCor Heart Monitor system is comparable to a conventional 12-lead ECG, Dr. Omar Dawood said in an interview at the conference. He is a clinical adviser to AliveCor, a surgeon by training who now works with technology companies. And results of two small Australian trials in clinical settings suggest that the AliveCor system is easily used on patients by pharmacists or nurses and is cost-effective.
In one study, pharmacists screened 1,000 pharmacy customers aged 65 years or older using the AliveCor system. A cardiologist read the results, and patients with suspected new atrial fibrillation were referred to general practitioners for conventional 12-lead ECG.
The AliveCor screening identified new cases of atrial fibrillation in 1.5% of patients and a 6.7% prevalence of atrial fibrillation in the cohort. The automated AliveCor algorithm was 98.5% sensitive and 91.4% specific for atrial fibrillation, reported Nicole Lowres of the University of Sydney, and her associates (Thromb. Haemost. 2014;111:1167-76). The investigators also estimated the incremental cost-effectiveness if AliveCor screening were extended into the community, with some patients receiving prescriptions for warfarin and 55% of those adhering to the medication regimen. They calculated a cost in U.S. dollars of $4,066 per quality-adjusted life-year gained and $20,695 to prevent one stroke.