“I have seen some of these commercial monitoring devices be helpful in identifying atrial fibrillation with a rapid heart rate,” Cedric Dark, MD, MPH, associate professor of emergency medicine at Baylor College of Medicine, tells SELF.
In fact, Ali Jamehdor, DO, an emergency medicine physician and medical director of the Weingart Foundation Emergency Department at Providence Saint John’s Health Center in Santa Monica, tells SELF that the ability to detect atrial fibrillation is one of the best features of these devices. “A lot of times people will not have any idea that they have this irregular heartbeat because they may not even sense it,” he says. “This has been, in my opinion, one of the most important things these instruments are good for.”
But as Woodhall discovered, smart devices can raise the alarm for things outside the cardiac realm too. After all, along with tracking the beats of your ticker, many also measure temperature, respiration, and other data points.
While Dr. Dark says that heart rate monitoring is one of the more useful features of these devices from an emergency medicine standpoint, he also believes that real-time temperature tracking is also handy. “Fever is a key sign of an infection like appendicitis,” he says.
Together, “these two are very important vital signs” docs can use to get a measure of your health, Erin Muckey, MD, associate professor of emergency medicine at Rutgers New Jersey Medical School, tells SELF.
There are limitations to these devices, though.
According to the docs we spoke to, while health trackers can be helpful in detecting serious issues, they’re not perfect. That’s a fact many of these trackers are upfront about.
Oura, for example, states that its temperature readings are 92% accurate under real-world conditions. Its night time resting heart heart rate measurement is 99.6% accurate, while its heart rate variability (the variation in time between consecutive heart beats) is 98% accurate when compared to a medical-grade electrocardiogram (ECG), which measures the heart’s electrical activity. The brand also stresses that the ring isn’t a medical device, and isn’t designed to diagnose or monitor medical conditions.
As for the Apple Watch, the fine print includes caveats about what the watch features are and are not capable of doing, including the fact that it’s not constantly monitoring for AFib so it may not detect all instances. Apple also notes that the companion ECG app cannot detect heart attack, stroke, blood clots, or other heart-related conditions. The company stresses the importance of seeking immediate help if you experience concerning symptoms.
What’s more, using these kinds of devices inaccurately—say, if they don’t fit quite right—may throw off readings too. That’s something Dr. Muckey says she’s personally experienced. “Sometimes my watch says my heart rate is half of what it is, even though I’m breathing hard, and I notice that it’s loose,” she says. “You just have to use your own judgement to say that a reading doesn’t make sense.”
Okay: I just got an alert from my health tracker. Is it time to freak out?
If you happen to get an alert from your health tracker, don’t panic. But doctors say it’s worth at least paying attention to this information if you’ve been using your device correctly. That’s especially true if you’re also having other symptoms—like dizziness, trouble breathing, chest pain, and feeling faint—along with the alert, Dr. Dark says. Or, say, the severe stomach pains Woodhall experienced.