Atrial Fibrillation, or AFib, is the most common form of arrhythmia, a condition that can cause the heart to beat too fast, too slow, or just plain irregularly. People with this disorder don't always feel symptoms, but it increases their risk of a stroke or heart failure.
The holy grail is to use the heart-rate sensors embedded in a consumer-facing device, like an Apple Watch, to identify those who are at risk. But it remains unclear whether the current crop of devices are accurate enough to be used for clinical purposes.
Developers at the Health eHeart study at UC San Francisco and Cardiogram, maker of a heart-tracking app, have teamed up to investigate whether the sensors built into the Apple Watch can be used to identify those at risk. The observational study, dubbed "mRhythm," kicks off today with the tagline "Contribute your data and save lives."
Brandon Ballinger, a cofounder of Cardiogram, tells Fast Company that the researchers have two major goals for the study: Quantify the accuracy of the Apple Watch sensor for the purposes of clinical research, and collect evidence that the Cardiogram app and algorithm can detect AFib.
Most experts say that heart-rate tracking using a smartwatch in only appropriate for casual use, rather than for medical purposes. A chest strap that closely emulates a real EKG machine is typically more accurate than a wrist-worn device. Perspiration and rapid movement, for instance, can affect a smartwatch's ability to accurately measure heart rate.
But for Ballinger, that doesn't rule out the smartwatch. "We are trying to understand the distribution of errors when you're sitting or walking, or male versus female," he says. He is hoping to recruit 10,000 patients, including those who aren't at high risk for heart disease. In the coming months, his team will incorporate other devices that track heart rate, including Fitbit fitness trackers.
Cardiogram isn't the only heart-health startup that is making a bet on the Apple Watch. Alivecor, a medical device startup, today introduced Kardia Band, a watchband for Apple's timepiece that is capable of performing a medical-grade electrocardiogram, or EKG, to check for problems with the electrical activity of the heart.
The company refers to its device as a "breakthrough," claiming that it is the first technology for providing instant EKG analysis on a wearable device that is approved by the U.S. Food and Drug Administration. The Kardia band comes with an app (available today), that displays the EKG in real time.
The device requires that the user touch the Kardia Band's sensor, which sends information to the app. The algorithm underlying the app will then look for signs of AFib. The system also includes a "Normal Detector," which indicates whether heart rate and rhythm are in the normal range, as well as a feature that sends a notification to users when they need to retake the EKG. Users can share their data with a health professional at any time.
AliveCor spokeswoman Rebecca Phillips says the Kardia Band can function effectively on the wrist. In fact, in only requires good contact between the electrode and the skin, "anywhere on the forearm to the fingertip." Sweat doesn't impact the results, she says, and tattoos won't interfere with the EKG.
The Kardia system is intended for patients who have been diagnosed with AFib. But Phillips says that it's also relevant to those with a family history of heart disease, as well as "early adopters" of new technology.