A new smartphone app has been developed that allows patients to detect an irregular pulse caused by atrial fibrillation (AF). Lead investigator Dr. David McManus of the University of Massachusetts Medical School, explained that patients with AF often wear Holter monitors, portable devices used to continuously monitor electrical activity of the cardiovascular system, for up to 30 days to capture an AF event, but physicians may often choose not to use the monitors due to the infrequency of paroxysmal events. A phone-based rhythm-assessment tool would have positive implications for accessibility, allowing patients to record their pulse while the event is occurring to determine whether they are in fact having an episode of AF, Dr. McManus states.
The study, published online in Heart Rhythm, was conducted with an app that used the smartphone camera and flash to illuminate the fingertip when placed on top of the camera surface.
Seventy-six adults with persistent AF were involved in the study. Each subject placed their finger on an iPhone 4S camera for two minutes while the program ran. Following the cardioversion procedure, patients successfully converted to normal sinus rhythm again reapplied their finger to the smartphone as another recording was obtained. The sensitivity of the app was quite impressive (0.962), as was the specificity (0.975) and accuracy (0.968) in detecting an irregular pulse from atrial fibrillation.
"Patients want this at their fingertips," Dr. McManus stated. "They want something quick, they wanted something that's accurate, and they want something that allows them to communicate effectively with their doctor, all the more reason for it to be a phone-based program." The application allows users to send the results directly to their physician via email and also provides summaries of atrial-fibrillation burden over selected time periods.
This is very interesting technology, says Dr. Ross. Although it might be easier for people with AF to be instructed in taking their own pulse, that would not permit a rapid communication with the patient s doctor, as this does. So this is a pretty cool app.