Apple Working With Johnson & Johnson on 'Heartline Study' Aimed at Reducing Risk of Stroke

Apple and Johnson & Johnson today announced a new study that aims to gather more information surrounding atrial fibrillation and other conditions tracked by iPhone and Apple Watch. The "Heartline Study" will include an ‌iPhone‌ app, and explores whether health tracking features of ‌iPhone‌ and heart health features on Apple Watch can improve health outcomes.

heartline study
The study is specifically aimed at individuals over 65 years of age. Apple and Johnson & Johnson are looking to see if Apple's health tracking technology can help reduce the risk of stroke thanks to earlier detection of atrial fibrillation, which is a leading cause of stroke in the United States and detectable with the Apple Watch's ECG feature.

The main issue with atrial fibrillation is that it is difficult to diagnose, due to the lack of physical symptoms in most patients. With Apple Watch, watchOS can alert users to a potential AFib event even if they are unaware of what's happening to them.

"Apple technology is making a meaningful impact on scientific research through the powerful capabilities of iPhone and Apple Watch, all with privacy at the center of the participant experience," said Myoung Cha, Apple's Head of Health Strategic Initiatives. "The Heartline Study will help further understanding of how our technology could both contribute to science and help improve health outcomes, including reducing the risk of stroke."

Those interested in the study must be 65 or older, a U.S. resident for the duration of the study, have traditional Medicare, own an ‌iPhone‌ 6s or later (with iOS 12.2 or later), and agree to provide access to their Medicare claims data. Once randomized participants are selected, they will be divided into two groups: one will only use the ‌iPhone‌ app and the other will use the ‌iPhone‌ app in addition to obtaining an Apple Watch. The study will last three years.

Apple and its devices regularly participate in scientific studies, most recently at Stanford Medicine with the "Apple Heart Study." This study began in 2017, and in November 2019 Stanford Medicine published results that ultimately determined the Apple Watch can successfully detect atrial fibrillation.

Related Roundup: Apple Watch 11
Buyer's Guide: Apple Watch (Neutral)

Popular Stories

Apple Logo Zoomed

Tim Cook Teases Plans for Apple's Upcoming 50th Anniversary

Thursday February 5, 2026 12:54 pm PST by
Apple turns 50 this year, and its CEO Tim Cook has promised to celebrate the milestone. The big day falls on April 1, 2026. "I've been unusually reflective lately about Apple because we have been working on what do we do to mark this moment," Cook told employees today, according to Bloomberg's Mark Gurman. "When you really stop and pause and think about the last 50 years, it makes your heart ...
wwdc sans text feature

Apple Rumored to Announce New Product on February 19

Thursday February 5, 2026 12:22 pm PST by
Apple plans to announce the iPhone 17e on Thursday, February 19, according to Macwelt, the German equivalent of Macworld. The report, citing industry sources, is available in English on Macworld. Apple announced the iPhone 16e on Wednesday, February 19 last year, so the iPhone 17e would be unveiled exactly one year later if this rumor is accurate. It is quite uncommon for Apple to unveil...
Finder Siri Feature

Why Apple's iOS 26.4 Siri Upgrade Will Be Bigger Than Originally Promised

Friday February 6, 2026 3:06 pm PST by
In the iOS 26.4 update that's coming this spring, Apple will introduce a new version of Siri that's going to overhaul how we interact with the personal assistant and what it's able to do. The iOS 26.4 version of Siri won't work like ChatGPT or Claude, but it will rely on large language models (LLMs) and has been updated from the ground up. Upgraded Architecture The next-generation...
iOS 26

iOS 26.3 and iOS 26.4 Will Add These New Features to Your iPhone

Tuesday February 3, 2026 7:47 am PST by
While the iOS 26.3 Release Candidate is now available ahead of a public release, the first iOS 26.4 beta is likely still at least a week away. Following beta testing, iOS 26.4 will likely be released to the general public in March or April. Below, we have recapped known or rumored iOS 26.3 and iOS 26.4 features so far. iOS 26.3 iPhone to Android Transfer Tool iOS 26.3 makes it easier...
iphone 17 pro dark blue 1

iPhone 18 Pro Max Rumored to Deliver Next-Level Battery Life

Friday February 6, 2026 5:14 am PST by
The iPhone 18 Pro Max will feature a bigger battery for continued best-in-class battery life, according to a known Weibo leaker. Citing supply chain information, the Weibo user known as "Digital Chat Station" said that the iPhone 18 Pro Max will have a battery capacity of 5,100 to 5,200 mAh. Combined with the efficiency improvements of the A20 Pro chip, made with TSMC's 2nm process, the...

Top Rated Comments

Hodar1 Avatar
78 months ago
My wife has had 5 ischemic stroke ('https://www.bing.com/search?q=ischemic+stroke&FORM=AWRE')s, anything - and I do mean ANYTHING, that can help prevent someone else from going through this, is a gift from God. You truly have no idea how much you have, until it's gone.
Score: 14 Votes (Like | Disagree)
jwh49 Avatar
78 months ago
It was my Apple Watch that alerted me to A-fib last October, thank God!
Score: 11 Votes (Like | Disagree)
dwhittington Avatar
78 months ago
Lifesaving technology is technology that matters.
Score: 3 Votes (Like | Disagree)
victorm1 Avatar
78 months ago

Good research by a marketing driven company? First question should be: how does this ‘study’ increase the sales (profit) of these companies?
J&J in particular happens to be extremely infamous for their rather shameless marketing of pharmaceuticals. Pardon me if I’m not leaping at the opportunity to celebrate.
Score: 3 Votes (Like | Disagree)
digitalexplr Avatar
78 months ago

Apple should make ECG available to the rest of the world first... (not available in Mexico -or anywhere in LatinAmerica for that matter- yet...)
It's not up to Apple. It's up to the regions regulators. In the U.S. the Food and Drug Administration (FDA) had to approve the use of the AW4 as a medical device.
Score: 3 Votes (Like | Disagree)
Stevez67 Avatar
78 months ago
Good research, if done correctly. I miss the cut-off by a couple years or I'd be all in.
Score: 2 Votes (Like | Disagree)