Atrial FibrillationEQUALNCT05686330
Detection and Quantification of Atrial Fibrillation in High-risk Patients Using a Smartwatch Wearable (Apple Watch)
A study testing Apple Watch in people with Atrial Fibrillation, run by Amsterdam University Medical Centers (UMC), Location Academic Medical Center (AMC) at 2 sites in Netherlands.
Trial summary
This is a randomized controlled trial evaluating atrial fibrillation (AF) detection through smartwatch-based screening in high-risk patients using an Apple Watch with integrated PPG and ECG functions. Read more about this study
- Who is it for?
- Ages 65 years and older
- Conditions the study is for
- Atrial Fibrillation
- What is being tested?
- Apple Watch
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 436 participants
- Where
- 2 sitesNetherlands
- Study dates
- 16 Nov 2022to 17 Jul 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 65 years and older
- All sexes
- No healthy volunteers
- Older adult
Who may be able to join
- Age ≥ 65 years
- Chadsvasc score ≥2 for men and ≥ for women at the time of eligibility screening
- Written informed consent as documented by signature from the participant
- Possession of iPhone (6S or later)
Who cannot join
- Diagnosis of atrial fibrillation or atrial flutter
- Currently on anticoagulation therapy
- Cardiac implanted electronic device (pacemaker, ICD)
- Smartwatch cannot be worn due to comprehensible reasons (allergic reactions, wounds, amputations, other)
- Significant mental or cognitive impairment
Trial locations and contacts
2 sites in 1 country.
Netherlands2 sites
Cardiology Center of the Netherlands
Amsterdam, North Holland
Spaarne Gasthuis
Haarlem, North Holland, 2035 RC
About this study
Official title: Enhanced Detection and Quickened Diagnosis of Atrial Fibrillation Using the Apple Watch: A Randomised Controlled Trial (EQUAL Study)
This is a randomized controlled trial evaluating atrial fibrillation (AF) detection through smartwatch-based screening in high-risk patients using an Apple Watch with integrated PPG and ECG functions.
Read the detailed description
This is a multicenter randomized controlled trial evaluating whether six months of heart rate and rhythm monitoring with a smartwatch (Apple Watch Series 5 or 8) equipped with photoplethysmography (PPG) and ECG functions increases atrial fibrillation (AF) detection in high-risk cardiac patients (age ≥65, CHA₂DS₂-VASc ≥2 for men, ≥3 for women) without previously known AF.
Patients are randomized to either smartwatch-based monitoring or standard care. Participants in the intervention group receive an Apple Watch paired with a smartphone app and are instructed to wear the device for at least 12 hours per day. Continuous rhythm monitoring is performed using PPG, with ECGs recorded upon symptom onset or irregular rhythm detection. ECG data are transmitted via the app to a secure platform and reviewed within 24 hours by an independent eHealth team supervised by a cardiologist. Patients and their treating physicians are notified upon new AF diagnoses.
To evaluate the primary endpoint, a total of 218 patients per arm were required according to the sample size calculation.
- Conditions
- Atrial Fibrillation
- Being tested
- Apple Watch
- Keywords
- Atrial fibrillation, Cardiac arrhythmia, Smartwatch, Wearable technology, Digital health, Photoplethysmography, Electrocardiography, Remote monitoring, Screening, Randomized controlled trial, Outpatient care, Telemedicine
- Medical subject headings
- Atrial Fibrillation, Arrhythmias, Cardiac
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Apple WatchDevice
Also called Smartwatch
Smartwatch for detecting atrial fibrillation using photoplethysmography (PPG)
| Study group | Role | What they receive |
|---|---|---|
| Interventional group (Apple watch) | Experimental | These participants will wear a smartwatch (Apple Watch) for 6 months during 12 hours a day. The smartwatch will alarm the participant if an irregular heart rhythm is detected. When a participant experiences any symptoms or receives an irregular heartbeat notification, they can record an ECG with the smartwatch. The ECG will automatically be sent to the Telecure team for evaluation. Receives: Device: Apple Watch |
| Control group | No intervention | Patients in the control group received standard care, which could include conventional rhythm monitoring methods such as Holter monitoring, in-hospital telemetry, or the use of handheld mobile ECG devices, at the discretion of the treating cardiologist. At the end of the study period the investigator will either call the participant to check for these outcome measures. |
What is being measured
The primary outcome is the main question the study is designed to answer.
The incidence of atrial fibrillation
Detected with an Apple watch or with any other device such as a holter or on an ECG or telemetry
Measured: 6 months
Secondary outcomes (5)
The time until atrial fibrillation is first detected (days)
The number of days between the date of inclusion and the date AF is detected
Measured: 6 months
The number of patients for whom medication for AF is initiated at the end of the study (anticoagulation and antiarrhythmic drugs)
Measured: 6 months
The number of patients that undergo major cardiovascular events during the study period
Measured: 6 months
Number of emergency department visits
Emergency department visits that take place during the study period, for any reason
Measured: 6 months
The number of new arrhythmia diagnoses other than AF in each study arm
Detected by either the Apple watch, telemetry, holter or other devices used to detect arrhythmias
Measured: 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jan 2023
- Study start16 Nov 2022
- Primary completion17 Jul 2025
- Study completion17 Jul 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Atrial FibrillationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 436 participants (actual)
Sponsor and investigators
- Lead sponsor
- Amsterdam University Medical Centers (UMC), Location Academic Medical Center (AMC)
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Prof. Dr. Arthur A. M. Wilde, Amsterdam University Medical Centers (UMC), Location Academic Medical Center (AMC)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05686330
- Sponsor's protocol ID
- 2021_209
- Acronym
- EQUAL
- Status last verified
- Sep 2025
- First submitted
- 16 Dec 2022
- Last updated
- 16 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- Undecided
Publications
van Steijn NJ, Blommestijn IS, Blok S, Pepplinkhuizen S, Somsen GA, Knops RE, Breukel L, Tijssen JGP, Tulevski II, Croon PM, Winter MM. Enhanced Detection and Prompt Diagnosis of Atrial Fibrillation Using Apple Watch: A Randomized Controlled Trial. J Am Coll Cardiol. 2026 Apr 14;87(14):1714-1728. doi: 10.1016/j.jacc.2025.11.032. Epub 2026 Jan 22.
PubMed 41569211
Study at a glance
From the registry record, last updated by the sponsor on 16 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Enhanced Detection and Quickened Diagnosis of Atrial Fibrillation Using the Apple Watch: A Randomised Controlled Trial (EQUAL Study)
- ClinicalTrials.gov ID
- NCT05686330
- Acronym / sponsor ID
- EQUAL / 2021_209
- Conditions
- Atrial Fibrillation
- Keywords
- Atrial fibrillation, Cardiac arrhythmia, Smartwatch, Wearable technology, Digital health, Photoplethysmography, Electrocardiography, Remote monitoring
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 436 participants (actual)
- Lead sponsor
- Amsterdam University Medical Centers (UMC), Location Academic Medical Center (AMC)University, hospital or other
- Study start
- 16 Nov 2022 (actual)
- Primary completion
- 17 Jul 2025 (actual)
- Study completion
- 17 Jul 2025 (actual)
- First posted
- 17 Jan 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a randomized controlled trial evaluating atrial fibrillation (AF) detection through smartwatch-based screening in high-risk patients using an Apple Watch with integrated PPG and ECG functions.
Detailed description
This is a multicenter randomized controlled trial evaluating whether six months of heart rate and rhythm monitoring with a smartwatch (Apple Watch Series 5 or 8) equipped with photoplethysmography (PPG) and ECG functions increases atrial fibrillation (AF) detection in high-risk cardiac patients (age ≥65, CHA₂DS₂-VASc ≥2 for men, ≥3 for women) without previously known AF.
Patients are randomized to either smartwatch-based monitoring or standard care. Participants in the intervention group receive an Apple Watch paired with a smartphone app and are instructed to wear the device for at least 12 hours per day. Continuous rhythm monitoring is performed using PPG, with ECGs recorded upon symptom onset or irregular rhythm detection. ECG data are transmitted via the app to a secure platform and reviewed within 24 hours by an independent eHealth team supervised by a cardiologist. Patients and their treating physicians are notified upon new AF diagnoses.
To evaluate the primary endpoint, a total of 218 patients per arm were required according to the sample size calculation.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Interventional group (Apple watch) | Experimental | Device: Apple WatchThese participants will wear a smartwatch (Apple Watch) for 6 months during 12 hours a day. The smartwatch will alarm the participant if an irregular heart rhythm is detected. When a participant experiences any symptoms or receives an irregular heartbeat notification, they can record an ECG with the smartwatch. The ECG will automatically be sent to the Telecure team for evaluation. |
| Control group | No intervention | –Patients in the control group received standard care, which could include conventional rhythm monitoring methods such as Holter monitoring, in-hospital telemetry, or the use of handheld mobile ECG devices, at the discretion of the treating cardiologist. At the end of the study period the investigator will either call the participant to check for these outcome measures. |
Who may qualify
- Ages
- 65 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Older adult
Key inclusion criteria (4 listed)
- Age ≥ 65 years
- Chadsvasc score ≥2 for men and ≥ for women at the time of eligibility screening
- Written informed consent as documented by signature from the participant
- Possession of iPhone (6S or later)
Key exclusion criteria (5 listed)
- Diagnosis of atrial fibrillation or atrial flutter
- Currently on anticoagulation therapy
- Cardiac implanted electronic device (pacemaker, ICD)
- Smartwatch cannot be worn due to comprehensible reasons (allergic reactions, wounds, amputations, other)
- Significant mental or cognitive impairment
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Apple WatchAlso: SmartwatchSmartwatch for detecting atrial fibrillation using photoplethysmography (PPG) | Device | Interventional group (Apple watch) |
Primary outcome
The incidence of atrial fibrillation
Time frame: 6 months
Detected with an Apple watch or with any other device such as a holter or on an ECG or telemetry
5 secondary outcomes
The time until atrial fibrillation is first detected (days)
Time frame: 6 months
The number of patients for whom medication for AF is initiated at the end of the study (anticoagulation and antiarrhythmic drugs)
Time frame: 6 months
The number of patients that undergo major cardiovascular events during the study period
Time frame: 6 months
Number of emergency department visits
Time frame: 6 months
The number of new arrhythmia diagnoses other than AF in each study arm
Time frame: 6 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Sep 2025.
- Derived from this study: PubMed 41569211van Steijn NJ, Blommestijn IS, Blok S, Pepplinkhuizen S, Somsen GA, Knops RE, Breukel L, Tijssen JGP, Tulevski II, Croon PM, Winter MM. Enhanced Detection and Prompt Diagnosis of Atrial Fibrillation Using Apple Watch: A Randomized Controlled Trial. J Am Coll Cardiol. 2026 Apr 14;87(14):1714-1728. doi: 10.1016/j.jacc.2025.11.032. Epub 2026 Jan 22.
- Individual participant dataSharing planned: Undecided
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Atrial Fibrillation (AF)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Apple Watch in people with Atrial Fibrillation, run by Amsterdam University Medical Centers (UMC), Location Academic Medical Center (AMC) at 2 sites in Netherlands.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 16 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Netherlands. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The incidence of atrial fibrillation (time frame: 6 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05686330, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Sep 2025.