APPLE WATCH COULD CREATE HEADACHES FOR DOCTORS.
When Apple unveiled its latest Apple Watch, one feature in particular was hailed as a “game-changer” — an app that allows people to take their own ECG, or electrocardiogram, in 30 seconds flat, anytime, anywhere — “right from the wrist.”
Apple called it the first over-the-counter ECG that can detect signs of an erratic heart rhythm. But observers say the watch could create a whole new level of anxiety for hypochondriacs, unnecessary testing and panicked visits to emergency. “The fear is we could end up with a lot of over treatment, over call and people waiting in emergency departments for no good reason,” said Dr. Samuel Vaillancourt of Toronto’s St. Michael’s Hospital.
The ECG app generates a “heart rhythm classification” that can determine if the heart is beating in a normal pattern or whether there are signs of atrial fibrillation, or AF. With AF, the heart quivers and can beat chaotically instead of contracting strongly with each beat. The risk is that blood can pool in the upper chambers of the heart, allowing clots to form and travel up to the arteries that feed the brain, causing a stroke.
The ECG app, which works like a single lead ECG (a normal ECG involves 12 leads stuck to the chest) won’t be available to American consumers until later this year. Apple, meanwhile, says it plans to work hard with other regulators, including Health Canada, to bring its wrist-worn ECG to worldwide markets.
AF affects some 34 million people worldwide and is a leading cause of stroke. According to the American Heart Association, Apple’s ECG app — which the heart association insists it does not endorse, even though its president spoke at the splashy unveiling — could led to quicker diagnosis of AF. All recording are stored in a health app that can generate a PDF that can be shared with a doctor.
However, studies have found that systematically screening large swaths of the population for AF isn’t “terribly productive,” says Montreal cardiologist Dr. Christopher Labos.
“The danger with any new medical technology is that in the enthusiasm to be an early adopter, for what is an admittedly cool gadget, we risk engaging in a population-wide screening strategy that is decidedly flawed,” Labos wrote in an article published by McGill University’s Office for Science and Society.
Screening people for AF isn’t recommended by the guidelines, “so in a sense no one needs to wear this on the wrist,” Labos said in an email.
Dr. Ethan Weiss, an associate professor at the University of California at San Francisco, went further, telling The Atlantic, “This is going to create such a massive headache” for doctors.
“Every worried (healthy) Tom, Dick and Harry are going to be freaking out about every blip thing that shows up on their Apple Watch,” Weiss said.
According to Labos, false positive are the main worry. And false positives — meaning the test shows something abnormal when there isn’t anything worryingly abnormal — become more common the healthier the people tested.
“Since the people who are more likely to buy an Apple Watch are younger and probably therefore healthier,” Labos said, having them wear an ECG on their wrist “24/7 is likely going to create a lot of false positives.”
In addition, atrial fibrillation isn’t something that will kill you, per se, added Labos, an associate with the McGill Office of Science and Society. “The main risk of AF is that it increases the risk of stroke.” If the person has other risk factors, such as high blood pressure, diabetes or older age, blood thinners can lower that risk.
However, blood thinners aren’t inconsequential drugs, and not everyone with AF needs blood thinners, said Vaillancourt, an emergency physician at St. Michael’s.
There are also always variations in the heart rate throughout the day, “and now we’re going to pick up much more of that signal,” Vaillancourt said. As well, a single-lead ECG also can’t diagnose a heart attack, “so that’s important to get across,” especially should the wearer suddenly start experiencing chest pain, but the ECG app doesn’t register anything unusual.
“It’s a tricky scenario,” added Dr. Andrew Ha, a cardiac electrophysiologist at the Peter Munk Cardiac Centre at Toronto’s University Health Network.
If the app does pick up something, it should be shared with a doctor and further testing done “to figure out if it’s atrial fibrillation, or if it’s nothing,” Ha said.
The likelihood of AF increases per decade. By age 80, it’s about 10 per cent, Ha said. “But when you’re in your 30s or 40s, it’s quite rare — probably less than one per cent.”
Some people are bothered by AF — they can’t function; they’re exhausted all the time. “Often patients come to us saying that they feel stuff, but we don’t have the rhythm recorded so we can’t really tell what’s going on,” Ha said. The Apple app could give doctors some objective proof of what the heart rhythm is doing, Ha said, although it should not be a substitute for a standard ECG.
However, other people with AF don’t have any symptoms at all.
“I think it behooves us as a medical profession to educate the public that, if you have Afib, it’s not the end of the world,” Ha said. Things get worrisome if there are other risk factors for stroke, he said, or if there are long periods of irregular rhythm, “like days and days, and the heart is really fast."