Last October we reported about a cardiac app under development by the Worcester Polytechnic Institute that aims to detect not only the heart rate, but also heart rhythm, respiration rate and blood oxygen saturation using the phone’s built-in video camera. As you can see above, the app is now really taking shape and it is expected to hit the market in three to six months, pending FDA approval.
As described before, the app uses the smartphone’s camera and light-source, detecting small changes in skin color and the appearance of underlying blood vessels at 30 fps as you hold your index finger over the camera for a minute or two (likely to be shorter in the final version). Due to the implementation of the light-source, the app will be compatible with the iPhone and most other smartphones, but not with the iPad. The phone will display a green indicator when everything is normal and a red one when an abnormal heart rhythm is detected. It also displays the heart rate, records symptoms and allows for data to be emailed to a doctor for further evaluation.
Although the app is not meant to replace any diagnostic devices, it could be used as a screening tool. Also it may be of use for patients with intermittent symptoms (paroxysmal atrial fibrillation) to register episodes over longer periods of time, either in existing patients for monitoring purposes or in new patients for detection of atrial fibrillation. A watch band type device might function to continuously acquire data or the app could be used once the patient experiences symptoms.
The app has been tested in 60 UMass patients with atrial fibrillation who were all correctly identified, giving it a 100% sensitivity, however as a screening tool it will be interesting to see if that doesn’t come at the price of losing too much specificity. We will keep you updated when the app becomes available. Meanwhile, there is still this Apple patent that if included as a feature on the next iPhone could make this technique instantly obsolete.
(hat tip: iMedicalApps)