Detection of Atrial Fibrillation Using PPG From Smartphone Cameras (FLASH AF)

August 19, 2026 updated by: Happitech BV

Detection of Atrial Fibrillation Using Photoplethysmography From Smartphone Cameras

The protocol is designed to enroll patients from at least 3 diverse clinical sites with smartphones who are being evaluated for the presence or absence of atrial fibrillation (AF) using the Heart Rhythm Software algorithm running on their smartphones. Algorithm output will be compared to a gold standard of 12-lead ECG recorded with a simultaneous PPG measurement.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide, and its prevalence is increasing and is expected to continue increasing for decades,. Detection of AF episodes may be useful for the identification of undiagnosed AF and in making clinical management decisions that include oral anticoagulation, restoration and maintenance of sinus rhythm, control of ventricular rate, and risk factor modification. Treatment of AF is associated with improvements of quality of life, stroke prevention, and reduced risk of heart failure.

Traditionally, diagnosis of AF is done using an electrocardiogram, with low amplitude or absent p-waves and narrow complex "irregularly irregular" pattern intervals seen on the ECG,. After diagnosis, there are a variety of methods that can be used to manage AF. Ambulatory ECG monitoring, implantable monitoring devices, and over-the-counter wrist-worn devices have been used to manage patients with AF,,. However, these devices are inconvenient and expensive which limits their wide adoption into clinical practice. There is an unmet clinical need for an easy to use and inexpensive over-the-counter FDA-cleared products that can detect episodes of AF in real-time and notify patients to seek out further care when AF is suspected.

Recent technological advancements have allowed for the identification of AF using smartwatches, with device manufacturers gaining over-the-counter regulatory clearance for their irregular heart rate detection algorithms,. These wrist-worn devices use a light-based measurement method called photoplethysmography (PPG) to measure changes in light absorbance and reflectance to understand changes in blood flow in superficial vasculature. The waveform generated from this measurement can be used to measure parameters like pulse rate, respiratory rate, pulse rate variability and others in addition to detecting AF. The increasing ubiquity of smartphones worldwide has led to greater availability of heart rhythm diagnostics using smartphone photoplethysmography (PPG). Smartphone camera PPG technology uses the light-emitting diode in cameras to measure pulsatile changes in light intensity that are reflected from a finger and can be used to detect AF. The widespread availability of this technology has the potential to improve the accessibility and convenience of heart rhythm monitoring, particularly in remote or underserved areas. This could result in improvements in early detection and management of AF, leading to better patient outcomes. Several smartphone PPG-based algorithms have been developed that utilize smartphones' built-in cameras to detect AF. The sensitivity and specificity of these algorithms for the detection of AF range between 81%-100% and 85%-100% respectively. However, there is a lack of evidence regarding the performance of these algorithms in detecting AF in an out-of-hospital setting using a gold-standard reference.

Happitech has developed a proprietary software development kit (SDK) that can be utilized to measure patients' cardiovascular parameters and identify potential pathologies including AF. Happitech's algorithm requires users to place a digit directly against their phone camera, and the camera and underlying algorithm detect subtle differences in blood flow to calculate physiological parameters for monitoring and clinical use.

The purpose of this study is to validate the performance of Happitech's PPG-based algorithm for the detection of AF against a 12-lead ECG in a diverse population of patients including cardiology patients being evaluated as inpatients or at a cardiology clinic visit.

Study Type

Observational

Enrollment (Estimated)

554

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Overijssel
      • Zwolle, Overijssel, Netherlands, 8025 AB
        • Recruiting
        • Isala Zwolle
        • Contact:
        • Principal Investigator:
          • Sebastien Krul, Doctor
    • Arkansas
      • Jonesboro, Arkansas, United States, 72401
        • Recruiting
        • Nair Research, LLC dba Arrhythmia Research Group LLC
        • Contact:
        • Principal Investigator:
          • Devi Nair, Doctor
    • Colorado
      • Littleton, Colorado, United States, 80210
        • Recruiting
        • South Denver Cardiology
        • Contact:
        • Principal Investigator:
          • Srikanth Sundaram, Doctor
    • Louisiana
      • New Orleans, Louisiana, United States, 70112
        • Not yet recruiting
        • Tulane University
        • Contact:
          • Kunal Sameer, Associate Director of Ops
          • Phone Number: 203-285-5666
          • Email: ksameer@tulane.edu
        • Principal Investigator:
          • Nassair Marrouchi, Doctor
    • Oklahoma
      • Oklahoma City, Oklahoma, United States, 73134
        • Recruiting
        • CardioVascular Health Clinic
        • Contact:
        • Principal Investigator:
          • Monica Lo, Doctor

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Male and female patients aged 22 years or older who are cardiology patients consulting the cardiac outpatient clinic, 50% of whom have a rhythm of atrial fibrillation at the time of enrollment, and own a smartphone.

Description

Inclusion Criteria:

  1. Adults aged 22 years or older
  2. Owns a smartphone and knows how to operate and navigate different applications.
  3. Individuals able to read, understand, and sign the consent form.
  4. Cardiology patients consulting the cardiac outpatient clinic.
  5. History of persistent AF or other cardiac rhythm

Exclusion Criteria:

  1. Participants with cognitive impairments
  2. Individuals who cannot read, speak, and/or understand English
  3. Patients with implantable neurostimulators, cardiac implantable device in an atrial or ventricular paced rhythm documented on a 12-lead ECG during the initial study visit

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Sinus Rhythm
Patient visiting the Cardiology Clinic in Sinus Rhythm
12 Lead ECG is compared to a smartphone based PPG
Atrial Fibrillation
Patient visiting the Cardiology Clinic in Atrial Fibrillation
12 Lead ECG is compared to a smartphone based PPG
Other
Patient visiting the Cardiology Clinic with neither Sinus Rhythm or Atrial Fibrillation
12 Lead ECG is compared to a smartphone based PPG

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
To evaluate the sensitivity and specificity of the Heart Rhythm Software
Time Frame: Through study completion, an average of 6 months

To evaluate the sensitivity and specificity of the Heart Rhythm Software algorithm running on a commercially available smartphone to detect atrial fibrillation segments using photoplethysmography (PPG) as measured through the phone's camera.

Se is defined as the percentage of patients with 90 second interval recordings scored by the Heart Rhythm Software algorithm as AF, out of all intervals determined by the Clinical Adjudication Committee (CAC) to be AF (gold standard).

Sp is defined as the percentage of patients with 90 second intervals scored by the Heart Rhythm Software algorithm as NSR out of all ECG recordings determined by the CAC to be NSR.

Through study completion, an average of 6 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Sensitivity & Specificity across subgroups
Time Frame: through study completion, an average of 6 months
The accuracy of the Happitech Heart Rhythm Software algorithm in detecting irregular rhythm suspected of AF and regular rhythm suspected normal sinus rhythm will be further investigated in subgroups defined by ethnicity, race, BMI, age group, smartphone type, and Fitzpatrick scale score. The sensitivity and specificity will be presented as an estimate and associated 95% CI's, as well as a Chi-square or Fisher's Exact p-value to assess if all levels of the subgroup are homogeneous.
through study completion, an average of 6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 30, 2026

Primary Completion (Estimated)

November 1, 2026

Study Completion (Estimated)

November 1, 2026

Study Registration Dates

First Submitted

August 11, 2026

First Submitted That Met QC Criteria

August 19, 2026

First Posted (Actual)

August 21, 2026

Study Record Updates

Last Update Posted (Actual)

August 21, 2026

Last Update Submitted That Met QC Criteria

August 19, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • HAPP-CTP-FDA-2025-002

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.