With the release of its latest Apple Watch, Apple touted features that detect if wearers have atrial fibrillation, but some cardiologists are questioning the feature's effectiveness and potential for harm, according to Politico.
When the watch detects an irregular hearth rhythm, it warns users, possibly prompting them to seek medical help.This is what cardiologists are concerned about, as many of the warnings could be false positives leading to unnecessary medical tests
Apple Watch users are typically younger, wealthier and healthier, not the average profile for someone who needs to worry about atrial fibrillation. Cardiologists suggest that the watch may detect atrial fibrillation in people who are not seriously sick or at danger of a cardiac event.
"It might turn out to be the case that if you put a monitor on a hundred people who'll never turn out to have a stroke, some of them might have tiny amounts of afib throughout their life," Ann Arbor-based University of Michigan nuclear cardiologist Venk Murthy, MD, told Politico.
Cardiologists also don't know the percentage of healthy people who might have atrial fibrillation with no medical significance. It becomes concerning to think people are getting unnecessary treatment because atrial fibrillation treatment can involve a lifetime taking blood thinners.
The FDA seemed overly eager to approve the Apple Watch's atrial fibrillation feature, according to some people quoted in the Politico article. While the agency granted clearance of the new watch feature last fall, the company has published little performance data. In data that was published in December, Apple revealed the watch had sensitivity and specificity rates greater than 98 percent.
Cardiologists describe the sensitivity rate as a "moderately good" result, but Dr. Murphy told Politico: "Take a moderately good test and apply it to a population with a very low risk of atrial fibrillation, and you will have a lot of false positives."
And while FDA Commissioner Scott Gottlieb hailed his agency's approval of the watch's atrial fibrillation software as a "significant step forward in FDA policy because we decoupled review of the app from review of the watch itself," some critics have complained about his enthusiasm for Apple.
"The FDA is responsible for regulating the industry, not fostering its growth," Jason Brooke, a medical device expert wrote to Politico. "Their mission is to promote and protect the public health."