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Electrocardiography can't be recommended to screen either for atrial fibrillation or for cardiovascular disease risk in individuals without obvious symptoms, according to two draft statements from the U.S. Preventive Services Task Force (USPSTF).

The Task Force gave ECG screening for atrial fibrillation an I recommendation of insufficient evidence to make a recommendation for adults ages 65 and older without a prior diagnosis of the arrhythmia. This was the first time the USPSTF has considered ECG screening for atrial fibrillation.

It cited lack of any trials showing benefit over usual care but "adequate evidence that screening for atrial fibrillation with ECG is associated with small to moderate harms, such as misdiagnosis, additional testing and invasive procedures, and overtreatment."

The evidence on screening for atrial fibrillation will soon grow, though, with a number of studies expected to report findings over the next 3 or 4 years, USPSTF member Seth Landefeld, MD, of the University of Alabama at Birmingham, noted in an interview with 番茄社区.

While the draft recommendation statement acknowledged that various new devices, ranging from automatic blood pressure cuffs and pulse oximeters to wearable consumer devices, have the capability to assess heart rhythm, no specific recommendation was given on them.

The recently-approved Apple Watch ECG band (AliveCor KardiaBand) and other handheld approaches "are interesting new gadgets that will be marketed aggressively," Landefeld noted. However, "these approaches have not been tested or evaluated in randomized trials. The studies that have been done are inconclusive whether the benefits outweigh harm." He particularly sounded a note of caution about the substantial number of false positives in some of the studies on initial screening. "One of the things we are concerned about is [patients being] incorrectly started on anticoagulants, which are dangerous medications that have real harms when used inappropriately."

"We need evidence," Landefeld added. "The whole wearable device issue is an area where we're operating in a data-free environment."

AliveCor pointed out in a statement released in response to the USPSTF document that there are some data: “Existing research, such as the REHEARSE-AF study published in Circulation, demonstrates that screening with single-lead ECG in patients 65 years and older with increased risk of stroke is significantly more likely to identify AFib.”

While that doesn’t yet provide the proof of screening-averted adverse clinical outcomes that the USPSTF was looking for, AliveCor said it was “gratified that the task force supports additional research.”

In a separate draft document on screening for cardiovascular disease, the Task Force repeated its position issued in 2012, recommending against ECG testing people at low risk (D recommendation), citing at best a small to moderate improvement in reclassification of risk beyond traditional risk scores in studies it reviewed.

"For asymptomatic adults at low risk of CVD events, it is very unlikely that the information from resting or exercise ECG (beyond that obtained with conventional CVD risk factors) will result in a change in the patient's risk category that would lead to a change in treatment and ultimately improve health outcomes," the document said. "Serious possible harms are associated with resting or exercise ECG, specifically the potential adverse effects of subsequent invasive testing."

For patients at intermediate- to high-CVD risk, the USPSTF found inadequate evidence to determine net benefit that might outweigh those risks of ECG testing (I statement).

The USPSTF noted that their CVD screening determination squares with some professional guidelines, including the American College of Physicians and American College of Preventive Medicine, but differs notably from the American College of Cardiology, which says exercise ECG may be an appropriate option for adults at intermediate risk and is appropriate for adults at high risk.

Both draft recommendation statements were posted on the USPSTF for public comment, which is open until Jan. 22, 2018.

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