How the Apple Watch could boost heart health

The Apple Watch could help clinicians support patients on their cardiac rehabilitation journey.

Ross Durant was volunteering at his church just over a decade ago when he noticed he was dripping sweat. “I felt like an elephant was sitting on my chest,” recalls the former insurance underwriter. As it turned out, Durant, now 91, had suffered a heart attack.

Fellow volunteers gave him an Aspirin and called 911. At the hospital, doctors treated his heart with medications, and weeks later, he underwent surgery to reduce the risk of another attack. He then went through a six-month rehab program at the Toronto Rehabilitation Institute, where he learned more about diet and exercise, as well as how to measure his heart rate by holding his two fingers to the side of his neck.

Now, over 10 years later, Durant has found an easier way to track metrics and activities relevant to his heart health: through an Apple Watch. He’s one of 1,000 people with cardiovascular disease being followed over a five-year period for the KITE Research Institute's Health Metrics and Clinical Events study, also known as “HERACLES.” 

The study aims to understand how data picked up by Apple Watch – including heart rate, exercise levels and more – relate to long-term heart health outcomes. In addition to having access to Apple Watch data once participants have shared their consent, the researchers conduct in-clinic checkups before, during and after the study. Participants undergo electrocardiograms and stress tests to measure the heart’s electrical activity at rest and during exercise, as well as fitness, blood pressure and weight checks.   

HERACLES builds upon an initial study of 300 people in cardiac rehab conducted by the team that explored the relationship between watch metrics and other objectively measured fitness levels.  These are the first studies examining Apple Watch’s potential role in cardiac rehab. 

 Ninety per cent of study participants have improved their overall heart and lung function.

Daily monitoring means more trustworthy data

While wearables have helped people improve and monitor their health for years now – whether through tracking steps, sleep patterns or heart rate numbers – there haven’t been many formal studies on how devices can help in medical settings. 

The potential for this tech, however, is enormous. In the future, wearables like Apple Watch could help doctors know when to intervene, says Dr. Paul Oh, a Senior Scientist at KITE and Medical Director of the Cardiovascular Prevention and Rehabilitation Program at the University Health Network. 

“For example, if someone’s heart function is getting worse, maybe we’ll see that their activity pattern has been going down for days or weeks, or that their resting heart rate has been going up, indicating underlying physical stressors,” he says. 

As Dr. Oh explains, routine medical checkup visits represent “a tiny fraction” of people’s lives, while in cardiac therapy, “we are asking people to be active throughout the day, and we want a picture of overall day-to-day health.” A wearable helps providers support patients between appointments and provides the everyday encouragement and reminders that rehab therapists could only dream of being able to offer.

The results are promising so far, with 90 percent of participants evaluated after one year either increasing or maintaining their VO2 max – a measure of how much oxygen the participants take in and use during exercise. It’s an indicator of the overall function of their heart and lungs.

Lisa Cotie, a kinesiologist and researcher at KITE, says that many patients appreciate the reassurance of the watch, including that they can see whether they’re exercising within their “Goldilocks” target heart rate – meaning they’re pushing their hearts enough to get stronger, but not too much that they overexert themselves. 

“Especially after graduating from cardiac rehab, a lot of people are craving the extra monitoring and knowing that we at the cardiac rehab centre are connected with them in some way,” she says.

Dr. Oh says wearables have the potential to support patients in ways rehab therapists could previously only dream of. 

Boosting health literacy – and motivation

Jessica Nooyen, a research manager at KITE, sees the watch as a self-empowerment tool.

“People feel like they have more control over their health. In terms of health literacy, we’ve noticed an increase in understanding as to what parameters like heart rate and VO2 max mean, and what to look out for,” she explains. “You could talk about these things in cardiac rehab, but to actually see it displayed on your watch provides you with immediate feedback and a great opportunity for learning.”

Durant’s Apple Watch records his daily walks, strength-training exercises, and estimated cardio fitness levels during exercise. More than anything, the watch keeps him honest. He makes sure he closes his three Activity rings every day – which means he’s met his goals of burning a predetermined number of calories through activity, exercising for a predetermined number of minutes and standing up at regular intervals to counter the ill health effects of sitting. (Calories are calculated based on the person’s age, gender, weight, height, activity and heart rate.)

Some of his friends and family members also have an Apple Watch, and many of them have a “friendly competition” going on where they see who can complete their rings fastest each day. If his sister completes her rings before him, “I’ll get a little text, and it’ll have a little barb in it,” he says.

While Durant has had to get some tech support from his grandchildren on using the watch, in general, he finds the Apple Watch makes it easier for him to follow his heart health. “In rehab, one of the first things you learn is to check your pulse in exercise, using two fingers on your neck and counting,” he says. “The watch takes the grunt work out of it. It’s all there on your wrist.”

This Is KITE is a storytelling series that aims to excite and inspire audiences as well showcase the Institute’s people, discoveries and impressive range of research. The campaign will feature monthly stories and videos that chronicle key projects under KITE’s three pillars of research: Prevention, Restoration of Function, and Independent Living/Community Integration.