‘My smartwatch told me I had a heart problem’
Glenn Dyer couldn’t work out what went wrong every time he went running. Then his Apple Watch told him to get to a doctor urgently. It was right. Steve Kilgallon reports.
When Glenn Dyer went out for a run, his heart rate would spike and he’d suddenly lose energy. On one run, he had to walk 13km back home because he simply couldn’t continue.
Initially, doctors couldn’t work out what was wrong. He’d been delaying another visit, until his watch told him he had to go.
Prompted by an urgent alert from his Apple Watch, which was tracking his heart beat, Dyer returned to his cardiologist. And once he was there, she used data from the watch to help diagnose a heart condition and get Dyer back into his running shoes.
Dyer was lucky: Apple only issued the update detecting irregular heartbeats in March. And one American professor says the watch is more likely to send people to the doctors who have no need to visit.
But in his case, it worked. A $699 watch he bought two years ago has got him back on his feet.
Dyer, a former premier grade rugby forward, had wanted to run a marathon before he turned 40 and was deep into preparations for last November’s Auckland Marathon when he began experiencing a feeling he describes as his body shutting down.
His GP referred him to a heart specialist, but despite extensive testing, cardiologist Fiona Stewart couldn’t diagnose anything.
An injury meant he had to stop running for a while anyway, so it wasn’t until January this year when the condition reappeared, but worse. During a 5km race he experienced what felt like an asthma attack: ‘‘I was breathing through a straw, my heart rate shot up.’’
But the first Covid lockdown meant he stalled on returning to his GP for more tests. That’s when Apple released an update for its smartwatches which detects an irregular heartbeat (and can also be used as a fingertip ECG scan).
‘‘I began getting messages on my watch – it would come up bright yellow, saying ‘notice: we have detected an irregular heartbeat, if this is diagnosed, we suggest you go to the doctor’,’’ he says.
‘‘So I thought ‘maybe I do need to go to the doctor’. I tucked my tail between legs, went back to the doctor and they said ‘what are you here for?’ and I said ‘because my watch told me I had to come and see you’.’’
Dyer was a good target: he’s long tracked his training data, paying special attention to his watch’s record of his VO2 Max ( his lungs’ maximum oxygen intake, and a good measure of fitness).
He was referred back to Dr Stewart, who immediately downloaded pages of heart rate data from Dyer’s phone and could see he was suffering from a condition called atrial fibrillation, or ‘a-fib’, an abnormal heart rhythm where the heart beats fast and irregular.
Because it had previously only been sporadic, it had been hard to diagnose, but now Dyer was suffering it regularly, and had his smartwatch data to show it.
Dyer sent the data from his watch to his sister, an intensive care nurse in Canada, who was also able to see he was in atrial fibrillation.
Dyer wasn’t worried:
‘‘ I was almost wondering if the watch was making stuff up, so I wasn’t overly concerned.’’ He thinks health insurance companies should be studying the benefits of subsidising smartwatches to keep clients healthy.
When she spoke to the Sunday StarTimes, Stewart was about to perform an operation called a cardioversion on someone who had picked up their atrial fibrillation that weekend from their smartwatch. She’d seen another patient in the same situation the day before.
Dyer was one of the first patients to turn up thanks to a watch prompt, but she’s seen several since. ‘‘ It’s becoming an everyday practice – for those who can afford watches,’’ she says.
While Apple wouldn’t comment, it has a series of promotional videos with watchusers touting the life- saving features of the watch. Media reports in the UK and US tell of people whose watches alerted them to irregular heartbeats.
Stewart says Dyer’s case illustrates how the watch can be useful. She had suspected atrial fibrillation but, because his episodes were infrequent, had been unable to prove it until his watch began logging it. ‘‘It really is a big breakthrough in wearable technology and the only one to date that does says.
Stewart says the watch uses technology adapted from an existing fingertip heart rate sensor, and the quality of the data so far has been impressive. She says tele- consulting during the Covid lockdowns and the increasing use of home blood pressure monitoring devices shows that healthcare is rapidly heading in this direction.
But while she can see a clear benefit from the Apple Watch, she has a note of caution, saying wearable devices mean cardiologists’ workloads are ‘‘going up astronomically’’. There are other issues to consider, such as patients emailing monitoring data direct to doctors without checking their message has been seen. ‘‘We need to learn how to use these devices,’’ Stewart says. it reliably,’’ she
Glenn Dyer, above, was training for a marathon but now credits his smartwatch, right, for revealing health issues. Cardiologist Dr Fiona Stewart, left, says such cases show what a ‘‘big breakthrough’’ this technology is.
While undiagnosed atrial fibrillation can cause strokes and dementia in older patients (a blood thinner can reduce stroke risk by two- thirds), for patients like Dyer, AF is a nuisance, rather than life-threatening.
In his case, it was exerciseinduced atrial fibrillation, typically seen in young fit people who do lots of endurance exercise. Most notably, says Stewart, it was suffered by rower Rob Waddell, causing him to miss the 2004 Olympics, then suddenly slow down in his famous 2009 race-off with Mahe Drysdale for the national single-sculls seat.
For Dyer, the feeling was that ‘‘the body stops – everything feels heavy and you just stop.’’
In his case, an atrial fibrillation then degenerated into atrial flutter where the heart beats too often.
Among his treatment was a cardioversion, in which patients are anaesthetised, then have their heart shocked back into a regular rhythm. ‘‘It felt like a horse had kicked me in the chest,’’ says Dyer, ‘‘ and I had a Superman burn mark on my chest.’’
He also had a complex surgery called a pulmonary vein isolation, in which veins leading into the heart have circumvential burns to prevent their abnormal electrical activity getting into the heart.
‘‘It’s been a bit of a road back but Fiona was confident she would get me back to a normal rhythm,’’ he says.
Greg Marcus, professor of medicine at the University of California in San Francisco, says the use of smartwatches in heart care is ‘‘very promising – but I do worry the genie was let out of the bottle a little prematurely.’’
Marcus, who conducted a 2018 study of the accuracy of smartwatches in detecting heart problems, says his original study showed smartwatches could be ‘‘ surprisingly accurate’’ in
‘‘I tucked my tail between legs, went back to the doctor and they said ‘what are you here for?’ and I said ‘because my watch told me I had to come and see you’.’’ Glenn Dyer
diagnosing atrial fibrillation, but even accurate tests in a large and generally healthy population could result in ‘‘large numbers of false positive results’’.
He says there’s still work to make the devices more accurate, to identify those likely to benefit, and to manage the resources they use ‘‘without causing unnecessary stress or anxiety among those who experience a false positive result’’.
Another recent study analysing visits to the US Mayo Clinics found only 11 per cent of people who visited a doctor after noticing an abnormal pulse reading on their watch were diagnosed with a heart condition.
The study analysed six months of patient records mentioning the term ‘Apple Watch’ – 15 per cent of those who received an explicit alert had treatment.
Marcus says in his experience, they’ve been most useful in cases similar to Dyer’s, to spot symptoms of a heart rhythm disturbance, with the ECG feature helpful for a doctor to arrive at a diagnosis.
But, he says, ‘‘unfortunately, we still do not know how to optimally use these devices, especially for the purposes of screening for atrial fibrillation. It’s interesting that private industry has, in a sense, usurped the authority of medical professional societies and scientists, taking atrial fibrillation screening straight to the public without meaningful input regarding the actual consequences.’’
Since his study, he says, Apple has invested in its own study to understand the accuracy of the watch in detecting atrial fibrillation.
The Apple study, conducted with Stanford University, tried to allay fears of over-loading doctors by reporting that only 0.5 per cent of 400,000 patients received irregular heart rate messages, and, of those, 84 per cent were considered to be in a- fib at the time they got the message. Apple says it did pre- clinical development of the app which included 2300 control subjects and 400 subjects with diagnosed a- fib which showed 98 per cent of those who got the notification had either a- fib or another arrhythmia.
Marcus has heard anecdotal reports of new diagnoses solely from their smartwatch, but ‘‘also see many patients with unnecessary visits and healthcare utilisation that arise due to false alerts from these watches as well.’’ Guidelines written for consumers would help.
Meanwhile, the Apple Watch 6, the next version on the market, will also report blood oxygenation levels ( if levels drop low, they can reduce organ function and even lead to cardiac arrest).
Glenn Dyer has been out for a couple of steady jogs. He hopes when he comes off his drug regimen, his heart rate will remain stable, and he’ll be back running half-marathons next year.