Some doctors warn that smartwatches and other AFib-detecting wearable devices aren’t proven screening tools and say alerts for nonsevere cases can result in patient anxiety, costly testing, and unnecessary treatment. Here is a summary of an article from the WSJ.

“It’s possible that atrial fibrillation can be detected in patients at high risk, but has it been shown to reduce stroke rate in any study? No, and it certainly hasn’t been shown to reduce death,” says N.A. Mark Estes is a professor at the University of Pittsburgh School of Medicine and an expert with the American Heart Association.

Earlier this year, the U.S. Preventive Services Task Force, an independent panel of experts in evidence-based medicine, said there is insufficient evidence to weigh the benefits of AFib screening for asymptomatic adults over 50.

In a September software update, Apple introduced a way for AFib patients to use recent-model Apple Watches to track when their episodes occur and how long they last. But blood thinners lead some people to avoid injury by reducing physical activity that could otherwise keep them fit and protected against heart conditions, says Daniel Capurro, deputy director of the Centre for the Digital Transformation of Health at the University of Melbourne.

Cardiologists who study the benefits of smartwatches in early AFib detection say they have to be mindful of how accessible such devices are. He is involved in another study with Johnson & Johnson and Apple to determine whether early AFib detection with Apple Watches can reduce the risk of stroke and other cardiovascular conditions.

Marco Perez, associate professor of medicine at Stanford University, co-led an Apple-funded study from November 2017 to February 2019 about detecting irregular heart rhythms. Tony Faranesh, a research scientist at Fitbit, acknowledges that the wearables industry is still in the early days of understanding how helpful its devices might be in detecting cardiovascular irregularities.