Smartwatch-guided, time-limited blood thinner use for atrial fibrillation
The Rhythm Evaluation for Anticoagulation with Continuous Monitoring of Atrial Fibrillation Trial (REACT-AF)
['FUNDING_OTHER'] · NORTHWESTERN UNIVERSITY · NIH-11163342
This will compare taking a blood thinner continuously versus taking it only for short periods after an Apple Watch detects an hour of atrial fibrillation in people with paroxysmal or persistent AF and low-to-moderate stroke risk.
Quick facts
| Phase | ['FUNDING_OTHER'] |
|---|---|
| Study type | Nih_funding |
| Sex | All |
| Sponsor | NORTHWESTERN UNIVERSITY (nih funded) |
| Locations | 1 site (CHICAGO, UNITED STATES) |
| Trial ID | NIH-11163342 on ClinicalTrials.gov |
What this research studies
You would be randomly assigned to either take a direct oral anticoagulant (DOAC) every day like current care or to take the DOAC only when your smartwatch detects an atrial fibrillation episode lasting one hour or more. The trial uses an AF-capable smartwatch (Apple Watch) to continuously monitor heart rhythm and trigger time-limited anticoagulation in the smartwatch-guided group. It is a multicenter, open-label study with blinded assessment of outcomes, and will follow participants for stroke, bleeding, and other major events. The study focuses on people with paroxysmal or persistent AF who have a low-to-moderate risk of stroke (CHA2DS2-VASc score 1–4).
Who could benefit from this research
Good fit: Ideal candidates are adults with paroxysmal or persistent atrial fibrillation, a CHA2DS2-VASc score of 1–4, and the ability to wear and sync an AF-capable smartwatch.
Not a fit: People with high stroke risk, permanent AF, mechanical heart valves, other clear indications for continuous anticoagulation, or those unable/unwilling to use a smartwatch are unlikely to benefit from this approach.
Why it matters
Potential benefit: If successful, this approach could lower bleeding risk and improve quality of life by avoiding unnecessary continuous anticoagulation while preserving protection against stroke.
How similar studies have performed: Smaller observational studies and pilot efforts have suggested rhythm-triggered anticoagulation could reduce bleeding, but this large randomized trial is a new test of the strategy.
Where this research is happening
CHICAGO, UNITED STATES
- NORTHWESTERN UNIVERSITY — CHICAGO, UNITED STATES (ACTIVE)
Researchers
- Principal investigator: PASSMAN, ROD S — NORTHWESTERN UNIVERSITY
- Study coordinator: PASSMAN, ROD S
About this research
- This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
- Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
- For full project details, budget, and progress reports, visit the official NIH RePORTER page below.