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Taking people in United StatesPhase 3

Testing whether a smartwatch can guide blood thinner use in atrial fibrillation

Compares continuous blood thinners with smartwatch-guided, time-limited use in people with atrial fibrillation.

Plain-language title generated from the registry record
Registry title: The Rhythm Evaluation for AntiCoagulaTion With Continuous Monitoring of Atrial Fibrillation

Key facts

Where
Albuquerque, Atlanta, Aurora, Austin, Baltimore, Boston, Buffalo, Burlington, Chapel Hill, Charleston, Charlottesville, Chicago, Cincinnati, Clearwater, Columbia, Columbus, Dallas, Detroit, Duluth, Elk Grove Village, Evanston, Flemington, Gainesville, Grand Rapids, Hackensack, Houston, Indianapolis, Iowa City, Jacksonville, Kansas City, Littleton, Los Angeles, Madison, Miami, Milwaukee, Minneapolis, Naperville, New York, Oklahoma City, Paoli, Philadelphia, Phoenix, Piscataway, Pittsburgh, Providence, Queens, Richmond, Ridgewood, Royal Oak, Sacramento, Salt Lake City, San Diego, San Francisco, Sarasota, Scarborough, St Louis, Stanford, Staten Island, Stony Brook, Stuart, Tacoma, Valhalla, Warner Robins, Washington D.C., White Plains, Winston-Salem, Winter Haven, Wooster, Worcester, Wyomissing, and Ypsilanti, United StatesSee the 93 sites
Phase
Phase 3

Could this be for you?

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

  • Are you between 22 and 85 years old?

Source: NCT05836987, who can take part

Where in United States

  • University of New Mexico Health Sciences CenterAlbuquerque, United StatesTaking people
  • Presbyterian Healthcare ServicesAlbuquerque, United StatesNo longer taking part
  • Emory UniversityAtlanta, United StatesTaking people
  • University of ColoradoAurora, United StatesTaking people
  • Texas Cardiac Arrhythmia Research FoundationAustin, United StatesTaking people
  • Johns Hopkins UniversityBaltimore, United StatesTaking people
  • Beth Israel Deaconess Medical CenterBoston, United StatesTaking people
  • BMC - BrightonBoston, United StatesTaking people
  • Boston Medical CenterBoston, United StatesTaking people
  • Brigham and Women's HospitalBoston, United StatesTaking people
  • Mass General HospitalBoston, United StatesTaking people
  • St. Elizabeth's Medical CenterBoston, United StatesTaking people
  • Tufts Medical CenterBoston, United StatesTaking people
  • University at BuffaloBuffalo, United StatesTaking people
  • Lahey Hospital & Medical CenterBurlington, United StatesTaking people
  • University of North CarolinaChapel Hill, United StatesTaking people
  • Medical University of South CarolinaCharleston, United StatesTaking people
  • University of VirginiaCharlottesville, United StatesTaking people
  • Loyola University ChicagoChicago, United StatesTaking people
  • Northwestern UniversityChicago, United StatesTaking people
  • Rush University Medical CenterChicago, United StatesTaking people
  • University of ChicagoChicago, United StatesTaking people
  • University of Illinois ChicagoChicago, United StatesTaking people
  • The Lindner Center for Research and Education at The Christ HospitalCincinnati, United StatesTaking people
  • University of Cincinnati College of MedicineCincinnati, United StatesTaking people
  • BayCare Health SystemsClearwater, United StatesTaking people
  • MUSC Health Heart and VascularColumbia, United StatesTaking people
  • Ohio State University Medical CenterColumbus, United StatesTaking people
  • OhioHealth Research InstituteColumbus, United StatesTaking people
  • University of Texas Southwestern Medical CenterDallas, United StatesTaking people
  • Henry Ford HealthDetroit, United StatesTaking people
  • Essentia Health The Duluth ClinicDuluth, United StatesNo longer taking part
  • Alexian Brothers Health SystemElk Grove Village, United StatesTaking people
  • NorthShore University HealthSystemEvanston, United StatesTaking people
  • Advanced Heart and Vascular Institute of HunterdonFlemington, United StatesTaking people
  • University of FloridaGainesville, United StatesTaking people
  • Corewell Health (Former Spectrum Health)Grand Rapids, United StatesTaking people
  • Trinity Health Grand Rapids/Mercy HealthGrand Rapids, United StatesTaking people
  • Hackensack Meridian HealthHackensack, United StatesTaking people
  • Baylor College of MedicineHouston, United StatesTaking people
  • Houston Methodist HospitalHouston, United StatesTaking people
  • University of Texas Health Science Center at HoustonHouston, United StatesTaking people
  • Ascension St. VincentIndianapolis, United StatesTaking people
  • University of Iowa Hospitals and ClinicsIowa City, United StatesTaking people
  • Mayo ClinicJacksonville, United StatesTaking people
  • University Health Truman Medical CenterKansas City, United StatesNo longer taking part
  • South Denver Cardiology Associates, P.C.Littleton, United StatesTaking people
  • University of California Los Angeles (UCLA) HealthLos Angeles, United StatesTaking people
  • University of Southern California Keck School of MedicineLos Angeles, United StatesTaking people
  • University of WisconsinMadison, United StatesTaking people
  • University of Miami - Leonard S. Miller SOMMiami, United StatesTaking people
  • Medical College of Wisconsin/ Froedtert HospitalMilwaukee, United StatesTaking people
  • Hennepin Healthcare Research InstituteMinneapolis, United StatesTaking people
  • Minneapolis Heart Institute FoundationMinneapolis, United StatesTaking people
  • University of MinnesotaMinneapolis, United StatesTaking people
  • Midwest Cardiovascular InstituteNaperville, United StatesTaking people
  • Columbia University Medical CenterNew York, United StatesTaking people
  • NYU Langone HealthNew York, United StatesTaking people
  • Weill Medical College of Cornell UniversityNew York, United StatesTaking people
  • University of Oklahoma Health Sciences CenterOklahoma City, United StatesTaking people
  • Cardiology Consultants of PhiladelphiaPaoli, United StatesNot yet recruiting
  • Thomas Jefferson UniversityPhiladelphia, United StatesTaking people
  • Banner UniversityPhoenix, United StatesTaking people
  • Rutgers, the State University of New JerseyPiscataway, United StatesTaking people
  • Allegheny-Singer Research InstitutePittsburgh, United StatesTaking people
  • Rhode Island HospitalProvidence, United StatesTaking people
  • NewYork Presbyterian - QueensQueens, United StatesTaking people
  • James River CardiologyRichmond, United StatesTaking people
  • Virginia Commonwealth UniversityRichmond, United StatesTaking people
  • The Valley Hospital Inc.Ridgewood, United StatesTaking people
  • William Beaumont HospitalRoyal Oak, United StatesTaking people
  • UC Davis HealthSacramento, United StatesTaking people
  • University of UtahSalt Lake City, United StatesTaking people
  • Scripps HealthSan Diego, United StatesTaking people
  • Kaiser PermanenteSan Francisco, United StatesNot yet recruiting
  • Sarasota Memorial Health Care SystemSarasota, United StatesNo longer taking part
  • Maine Medical Partners MaineHealth CardiologyScarborough, United StatesTaking people
  • Washington University School of MedicineSt Louis, United StatesTaking people
  • Stanford UniversityStanford, United StatesTaking people
  • Staten Island University Hospital-Northwell HealthStaten Island, United StatesTaking people
  • Stony Brook UniversityStony Brook, United StatesTaking people
  • Cleveland Clinic FloridaStuart, United StatesNo longer taking part
  • St. Joseph Medical Center TacomaTacoma, United StatesTaking people
  • Westchester Medical CenterValhalla, United StatesTaking people
  • Georgia Arrhythmia Consultants and Research InstituteWarner Robins, United StatesTaking people
  • Medical Faculty Associates George Washington UniversityWashington D.C., United StatesNo longer taking part
  • White Plains HospitalWhite Plains, United StatesTaking people
  • Wake Forest Baptist HealthWinston-Salem, United StatesTaking people
  • Baycare Health Systems ClearwaterWinter Haven, United StatesTaking people
  • Wooster Community HospitalWooster, United StatesTaking people
  • UMass Chan Medical SchoolWorcester, United StatesNo longer taking part
  • Penn State Health Medical Group Berks CardiologyWyomissing, United StatesTaking people
  • Trinity Health Michigan Heart - Ann ArborYpsilanti, United StatesTaking people

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?
Print a page for my doctor

Trial details

Who runs it
Johns Hopkins University
Trial code
NCT05836987
Record updated
3 November 2026
Original description
REACT-AF is a multicenter prospective, randomized, open-label, blinded endpoint (PROBE design), controlled trial comparing the current Standard Of Care (SOC) of continuous Direct Oral Anticoagulation (DOAC) use versus time-delimited (1 month) DOAC guided by an AF-sensing Smart Watch (AFSW) in participants with a history of paroxysmal or persistent Atrial Fibrillation (AF) and low-to-moderate stroke risk.Read full original descriptionShow less

REACT-AF: Rhythm Evaluation for AntiCoagulaTion With Continuous Monitoring of Atrial Fibrillation

REACT-AF is a multicenter prospective, randomized, open-label, blinded endpoint (PROBE design), controlled trial comparing the current Standard Of Care (SOC) of continuous Direct Oral Anticoagulation (DOAC) use versus time-delimited (1 month) DOAC guided by an AF-sensing Smart Watch (AFSW) in participants with a history of paroxysmal or persistent Atrial Fibrillation (AF) and low-to-moderate stroke risk.

Inclusion: 22-85 years of age; English speaking participants. Spanish-only speakers may be included in the future at select sites appropriately translated; History of non-permanent atrial fibrillation; CHA2DS2-VASC score of 1-5 for men and 2-5 for women without prior stroke or Transient Ischemic Attack (TIA), The CHA2DS2-VASc score is a point-based system used to stratify the risk of stroke in Atrial Fibrillation (AF) patients. The acronym CHA2DS2-VASc stands for congestive heart failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled), vascular disease, age 65 to 74 and sex category (female). Congestive heart failure defined as: The presence of signs and symptoms of either right (elevated central venous pressure, hepatomegaly, dependent edema) or left ventricular failure (exertional dyspnea, cough, fatigue, orthopnea, paroxysmal nocturnal dyspnea, cardiac enlargement, rales, gallop rhythm, pulmonary venous congestion) or both, confirmed by non-invasive or invasive measurements demonstrating objective evidence of cardiac dysfunction and/or ejection fraction < 40%; The participant is on a DOAC at the time of screening and willing to stay on DOAC for duration of study; Willing and able to comply with the protocol, including:; Possession of a smart watch-compatible smart phone (iPhone that supports the latest shipping iOS) with a cellular service plan; Be willing to wear the smart watch for the suggested minimum of 14 hours a day; Expected to be within cellular service range at least 80% of the time; Willing and able to discontinue DOAC; The participant is willing and able to provide informed consent.

Exclusion: Current treatment with warfarin and unwilling or unable to take a DOAC; The participant is being treated with chronic daily oral NSAIDs and is unwilling or unable to discontinue use for the study duration. Use of low-dose aspirin is permitted; Any documented single AF episode lasting ≥ 1 hour on a cardiac monitor performed within 90 days prior to randomization; Prior or anticipated left atrial appendage occlusion or ligation; The participant is enrolled, has participated within the last 30 days, or is planning to participate in a concurrent drug and/or device study during the course of this clinical trial. Co-enrollment in concurrent trials is only allowed with documented pre-approval from the study manager; there is no concern that co-enrollment could confound the results of this trial; The participant has a tattoo, birthmark, or surgical scar over the dorsal wrist area on the ipsilateral side that the AFSW may be worn; Any concomitant condition that, in the investigator's opinion, would not allow safe participation in the study (e.g., drug addiction, alcohol abuse); Documented prior stroke (ischemic or hemorrhagic) or transient ischemic attack; History of ECG-documented, sustained atrial flutter that has not been treated with ablation (participants with atrial flutter who have been ablated are eligible for enrollment); Conditions associated with an increased risk of bleeding:; Major surgery in the previous month; Planned surgery or intervention in the next three months that would require cessation of anticoagulation > 2 weeks; History of intracranial, intraocular, spinal, retroperitoneal, or atraumatic intra- articular bleeding; Gastrointestinal hemorrhage within the past year unless the cause has been permanently eliminated (e.g., by surgery); Symptomatic or endoscopically documented gastroduodenal ulcer disease in the previous 30 days; Hemorrhagic disorder or bleeding diathesis; Need for anticoagulant treatment for disorders other than AF; Uncontrolled hypertension (Systolic Blood Pressure >180 mmHg and/or Diastolic Blood Pressure >100 mmHg); Existing cardiac rhythm device or indication for a permanent pacemaker, Implantable Cardioverter-Defibrillator (ICD) or Cardiac Resynchronization Therapy (CRT) device or planned insertable cardiac monitor. Insertable cardiac monitors are permitted unless they are being used to guide anticoagulation treatment; Mechanical prosthetic valve(s) or severe valve disease; Participant needs DOAC for reasons other than preventing stroke or arterial embolism resulting from AF (i.e., preventing Deep Vein Thrombosis (DVT) or PE) or needs permanent OAC (i.e., congenital heart defects, prosthetic heart valve); Participants deemed high risk for non-cardioembolic stroke (i.e., significant carotid artery disease defined as stenosis > 75%) based on the investigator's discretion; Known hypersensitivity or contraindication to direct oral anticoagulants; Reversible causes of AF (e.g., cardiac surgery, pulmonary embolism, untreated hyperthyroidism). AF ablation does not constitute reversible AF; > 5% burden of premature atrial or ventricular depolarizations on pre-enrollment cardiac monitoring; Stage 4 or 5 chronic kidney disease; Valvular or permanent atrial fibrillation; The participant is a woman who is pregnant or nursing; Known or suspected symptomatic or asymptomatic atrial fibrillation lasting ≥ 1 hour/month over the last 3 months; Ablation for AF within the last 2 months; Hypertrophic cardiomyopathy; The participant has a tremor on their ipsilateral side that the AFSW may be worn.

ClinicalTrials.gov NCT05836987