health

Apple Watch may spot heart problem but more research needed

More than 419,000 Apple Watch users signed up for the unusual study

A huge study suggests the Apple Watch can detect a worrisome irregular heartbeat at least sometimes — but experts say more work is needed to tell if using wearable technology to screen for heart problems really helps.

More than 419,000 Apple Watch users signed up for the unusual study, making it the largest ever to explore screening seemingly healthy people for atrial fibrillation, a condition that if untreated eventually can trigger strokes.

Stanford University researchers reported Saturday that the watch didn’t panic flocks of people, warning just half a per cent of participants — about 2,100 — that they might have a problem.

But even among those flagged, “it’s not perfect,” cautioned Dr. Richard Kovacs of the American College of Cardiology, who wasn’t involved with the study.

People who received an alert were supposed to consult a study doctor via telemedicine and then wear an EKG patch measuring cardiac activity for the next week to determine the watch’s accuracy. Some skipped the virtual check-up to consult their own doctors; overall, about 57 per cent sought medical attention.

Among those who got EKG monitoring through the study, a third had atrial fibrillation, according to preliminary results being presented at an American College of Cardiology conference in New Orleans.

A-fib tends to come and go, and a week of monitoring might have missed some cases, said Stanford lead researcher Dr. Mintu Turakhia. But if the watch detected another irregular heartbeat while someone was wearing the EKG patch, 84 per cent of the time it really was a-fib, he said.

“This study we believe provides very encouraging evidence that a device, the Apple Watch, can be used to detect a-fib and to point out to people when additional monitoring or testing may be needed,” said Dr. Lloyd Minor, Stanford’s dean of medicine.

Other cardiac experts said the study, which was funded by Apple, suggests screening with wearable technology might be technically feasible eventually, but needs lots more research.

“I would not advise this to the overall general population,” said Dr. Valentin Fuster, director of Mount Sinai Heart in New York and a former American Heart Association president, who wasn’t involved with the study. Instead, he’d like to see it tested in seniors with risk factors like high blood pressure.

What is atrial fibrillation?

A-fib occurs when the heart’s top chambers, called the atria, get out of sync with the bottom chambers’ pumping action. Sometimes patients feel a flutter or a racing heart but many times they’re not aware of an episode.

Sometimes the heart gets back into rhythm on its own. Other patients get an electric shock to get back into rhythm, or are prescribed blood thinners to counter the stroke-causing blood clots that untreated a-fib can spur. A-fib causes 130,000 deaths and 750,000 hospitalizations a year in the U.S.

How do doctors check for it?

A-fib is most common in older adults, and other risks include high blood pressure or a family history of arrhythmias. But routine screening isn’t recommended for people without symptoms. Studies haven’t yet proved that early detection from screening would prevent enough strokes to outweigh risks from unnecessary testing or overtreatment.

How does the Apple watch check for it?

A mobile app uses the optical sensor on certain versions of the watch to analyze pulse rate data. If it detects enough variation from beat to beat over a 48-hour period, the user receives a warning of an irregular heart rhythm.

The latest version of the Apple Watch also allows wearers to push a button to take an EKG and share the reading with doctors. Saturday’s study didn’t include watches with that capability.

Does the new study show mass screening is a good idea?

No. The study was designed to tell how the watch compared to a week of standard EKG monitoring — not if the wearer’s health improved because the screening uncovered the arrhythmia. To prove if detecting a-fib early lowers risk of stroke would require years of study.

And since the study didn’t have a comparison group getting routine EKGs, there’s no way to know if the watch missed heartbeat problems, giving a false sense of security, Kovacs said.

The puzzling low numbers of alarms might be because most participants were young or middle-aged, not the seniors who are most at risk for a-fib, he said.

Lauran Neergaard, The Associated Press

Like us on Facebook and follow us on Twitter.

Just Posted

Fraser Valley Bandits draft Abbotsford’s Joel Friesen first overall

Professional basketball team reveals 13 players selected at CEBL draft

Abbotsford council votes to increase their event expense limits

Increase needed in case annual conferences require significant travel, staff say

Plans redrawn for Fraser Valley Inn redevelopment

Owner of building scales back plans on inn site, adds proposal to build second low-rise

LETTER: Why is Jati Sidhu ashamed of his riding?

Lytton’s Christopher di Armani shares his dismay at the potential name change of the MP’s riding

Solitary confinement gets overhaul at Abbotsford prison

‘It’s more social,’ Matsqui Institution’s citizens advisory committee chair says

Sparks fly as SUV speeds down wrong side of Highway 1 trying to flee RCMP

Captured on video, the vehicle headed westbound against oncoming traffic before crashing

1,300 cruise ship passengers rescued by helicopter amid storm off Norway’s coast

Rescue teams with helicopters and boats were sent to evacuate the cruise ship under extremely difficult circumstances

Province announces $18.6 million for B.C. Search and Rescue

The funding, spread over three years, to pay for operations, equipment, and training

Vancouver-bound transit bus involved in fatal crash near Seattle

One man was killed and a woman injured in crash with bus purchased by TransLink

Late-season wave of the flu makes its round in B.C.

BC Centre for Disease Control reported 50 per cent jump in flu cases in first weeks of March

Tofino’s housing crisis causing some to seek shelter at the local hospital

Tofino’s housing crisis is pushing the town’s ‘hidden homeless’ population into the forefront.

Sentencing judge in Broncos crash calls for carnage on highways to end

Judge Inez Cardinal sentenced Jaskirat Singh Sidhu to eight years

Most Read