Wearables Could Reduce Need for Continuous Blood Thinners in Patients with Atrial Fibrillation
Posted on 28 Mar 2025
Atrial fibrillation (AFib) is the most prevalent heart arrhythmia, affecting over 5 million individuals in the United States, with projections suggesting that number could rise to 12.1 million by 2030. This condition is characterized by rapid and irregular heartbeats originating from the upper chambers of the heart. AFib significantly increases the risk of stroke, heart failure, dementia, and early death. To prevent stroke due to blood clots, many AFib patients are prescribed long-term oral anticoagulation therapy. However, these blood-thinning medications carry their own risks, such as excessive bleeding. Balancing the risks and benefits of prolonged anticoagulation therapy can be challenging for both patients and healthcare providers. Now, a new clinical trial will examine how wearable technology can help reduce dependence on these medications in individuals with AFib.
Researchers at Northwestern Medicine Bluhm Cardiovascular Institute (Chicago, IL, USA) are collaborating with other institutions on a seven-year clinical trial that will enroll participants from over 80 sites across the US. Participants will be randomly assigned to either continue the current standard of care, which involves continuous blood thinners, or follow a new approach using the “pill-in-pocket” method, guided by a study app on the Apple Watch. This trial will also assess whether this novel approach can reduce the occurrence of major bleeding events when compared to the traditional continuous therapy. The Rhythm Evaluation for AntiCoagulaTion (REACT-AF) trial aims to monitor participants' AFib episodes and explore whether it’s possible to reduce the lifelong use of blood-thinning medications.
The trial will rely on a custom study app for the Apple Watch, which will utilize the device’s advanced heart health features to track heart activity and alert patients when they are experiencing an AFib episode. Upon receiving an alert, participants will be instructed to take blood-thinning medications for a short period, only when they are at the highest risk for stroke. To take part in the trial, individuals must have an iPhone, and Apple Watch devices will be provided to participants through a contribution from Apple. If successful, this clinical trial could pave the way for a more tailored approach to preventing strokes related to AFib.
“We know that risk of stroke is greatest in the weeks following an episode of AFib then returns to a low level, which suggests the potential for anticoagulant therapy only as needed rather than every day of the year,” said Dr. Rod Passman, MD, MSCE, the principal investigator for REACT-AF. “However, many patients have no symptoms of AFib, so treating in the moment is challenging. That’s where wearable technology comes in.”
“If we can show this ‘pill-in-pocket’ strategy is equally protective against stroke and also reduces bleeding caused by these blood thinners, that could potentially save lives, reduce cost, improve quality of life and fundamentally change the standard of care for millions of patients living with AFib,” added Dr. Passman, who for ten years has studied solutions to end the standard “one-size-fits-all” practice of prescribing lifelong blood thinners to everyone with AFib.
Related Links:
Northwestern Medicine Bluhm Cardiovascular Institute
