Apple Watch detects irregular heart beat in large US study

The Apple Watch was able to detect irregular heart pulse rates that could signal the need for further monitoring for a serious heart rhythm problem, according to data from a large study funded by Apple Inc, demonstrating a potential future role for wearable consumer technology in healthcare.

Researchers hope the technology can assist in early detection of atrial fibrillation, the most common form of irregular heart beat. Patients with untreated AF are five times more likely to have a stroke.

Results of the largest AF screening and detection study, involving over 400,000 Apple Watch users who were invited to participate, were presented on Saturday at the American College of Cardiology meeting in New Orleans.

Of the 400,000 participants, 0.5 percent, or about 2,000 subjects, received notifications of an irregular pulse. Those people were sent an ECG (electrocardiography) patch to wear for subsequent detection of atrial fibrillation episodes.

A third of those whose watches detected an irregular pulse were confirmed to have atrial fibrillation using the ECG technology, researchers said.

Some 84 percent of the irregular pulse notifications were later confirmed to have been AF episodes, data showed.

“The physician can use the information from the study, combine it with their assessment ... and then guide clinical decisions around what to do with an alert,” said Dr. Marco Perez, one of the study's lead investigators from Stanford School of Medicine.

The study also found that 57 percent of participants who received an alert on their watch sought medical attention.