Verily Watch Cardio (AF and ECG) Study

Study Overview
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Brief Summary
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This study is designed to evaluate the performance of the Verily Watch Cardio for recording electrocardiogram (ECG) and photoplethysmography (PPG) signals and detecting suspected atrial fibrillation (AF) episodes, in a free-living environment, in participants at risk for having an AF event.

Official Title
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Verily Watch Cardio (AF and ECG) Study

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Device: Verily Watch Cardio
* Device: iRhythm Zio monitor
* Device: Schiller CARDIOVIT FT-1


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: At least 22 years old Able to read and speak English Participant understands the study requirements and is able and willing to sign written Informed Consent At risk of having an AF event, as determined by having a diagnosis of paroxysmal AF (PAF) and meeting one or more of the following: Scheduled or to be scheduled to undergo AF ablation AF burden of ≥25% in the 3 months prior to consent date as confirmed via an implantable loop recorder (ILR), holter monitor, or adhesive monitoring patch CHA2DS2VASc score ≥3 Left atrial diameter ≥4.4 cm as confirmed by transthoracic echo (TTE) within one year of consent Without significant limitation in ability to participate in the study, in the opinion of the Investigator Exclusion Criteria: Have a pacemaker or implantable cardioverter defibrillator (ICD) Currently on class Ic or class III antiarrhythmic medication that has been successful in eliminating AF (no documented AF of more than 30 seconds since the initiation of the medication). Should be at least one week off medication. Had successful AF ablation (no documented AF of more than 30 seconds post procedure) Known severe allergy to nickel or metal jewelry Known allergic reaction to polyester, nylon, spandex, adhesives or hydrogels; or with family history of adhesive skin allergies Are diagnosed with persistent AF Have an implantable neuro-stimulator Currently wearing an ECG patch that prevents the use of the FDA-cleared wearable ECG patch, at the discretion of the Investigator. Have discolored wrists (e.g., tattoos, ink), at the discretion of the Investigator.

Ages Eligible for Study
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Minimum Age: 22 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Paroxysmal Atrial Fibrillation Patients<br> | Device: Verily Watch Cardio<br>* The Verily Watch Cardio is an investigational wrist-worn wearable device containing multiple sensors to measure physiological and environmental metrics, including electrodes that enable a single-lead electrocardiogram (ECG) measurement and a photoplethysmogram (PPG) sensor to monitor for irregular pulses.<br>Device: iRhythm Zio monitor<br>* The iRhythm Zio monitor, the reference device, is an FDA-cleared single-patient use, continuously recording ECG monitor that can be worn for up to 14 days.<br>Device: Schiller CARDIOVIT FT-1<br>* The Schiller CARDIOVIT FT-1, the reference device, is an FDA-cleared portable 12-lead ECG machine capable of recording continuous standard 12-lead resting ECG for up to 4 minutes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity and Specificity of suspected AF episode detection | Sensitivity and Specificity of suspected AF episode detection by the irregular pulse detection algorithm | Up to 14 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A sensitivity analysis estimating the range of sensitivities and specificities | A sensitivity analysis estimating the range of sensitivities and specificities observed when imputing missing test device data | Up to 14 days | 
| Sensitivity and Specificity in defined subgroups | Sensitivity and Specificity in subgroups defined by: race, age-groups, activity level, skin-tone and AF-burden | Up to 14 days | 
| Mean difference in Interbeat interval (IBI) and the associated limits of agreement (LoA) | Mean difference in Interbeat interval (IBI) and the associated limits of agreement (LoA) based on recorded ECG data | Up to 14 days | 
| Participant-level and heartbeat level sensitivity/specificity of P-wave detection | Participant-level and heartbeat level sensitivity/specificity of P-wave detection based on recorded ECG data | Up to 14 days |