Diagnosis of Postoperative Atrial Fibrillation by a Smartwatch (FAWATCH)

Diagnosis of Postoperative Atrial Fibrillation After Cardiac Surgery by a Smartwatch: an Open-label Randomized Controlled Trial

The incidence of postoperative atrial fibrillation (POAF) after on-pump cardiac surgery remains high, at around 30%. POAF increases the risk of cardiac decompensation, stroke, acute myocardial infarction, and death, resulting in increased morbidity and mortality, hospital length of stay, and cost of patient management. Episodes of POAF are usually paroxysmal and asymptomatic, increasing the risk of developing permanent AF at five years by 4 to 5 times. POAF occurs between 3 and 4 days after cardiac surgery, mainly when the patient is hospitalized in a surgical ward without heart rate monitoring as opposed to critical care, where the patient benefits from continuous rhythmic monitoring. The diagnosis of POAF is therefore made with the help of a 12-lead electrocardiogram (ECG) when the patient presents clinical symptoms and when the medical staff notes a significant variation in heart rate. However, many patients with episodes of asymptomatic POAF have a higher risk of stroke and mortality than those with symptomatic POAF.

Faced with this public health problem, the development of tools for diagnosing AF is in full swing, mainly the marketing of smartwatches (SWs) that allow for the performance of 1-lead ECG. SW is also equipped with algorithms to analyze heart rate variability and diagnose asymptomatic atrial fibrillation (AF) episodes. The European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) recommend the use of smartwatches to detect AF, in particular, to reduce the economic impact of AF.

The aim of the study is to diagnose POAF within the first five days after patient discharge from the critical care unit for the cardiac surgery department.

Study Overview

• Status: Recruiting
• Conditions: Atrial Fibrillation; Cardiac Surgery
• Intervention / Treatment: Procedure: ECG; Procedure: scanwatch

• Study Type: Interventional
• Enrollment (Estimated): 324
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Christophe Beyls, MD; Phone Number: 03 22 08 78 66; Email: beyls.christophe@chu-amiens.fr

Study Locations

• France
  • Amiens, France
    • Recruiting
    • CHU Amiens Picardie
    • Contact: Christophe Beyls, MD; Phone Number: 0322087866; Email: Beyls.Christophe@chu-amiens.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patient (>18 years old)
• The patient was hospitalized at Amiens University Hospital for on-pump cardiac surgery.
• The patient has had a recent on-pump cardiac surgery (< 96h)
• Patient with the motor and cognitive abilities to perform a 1-lead ECG with the smartwatch
• The patient was transferred to the cardiac surgery department of Amiens University Hospital.
• The beneficiary of a social security plan
• Signature of the consent to participate in the study

Exclusion Criteria:

• History of AF
• Need for rhythmic monitoring by telemetry in cardiac intensive care for atrioventricular block and rapid supra and ventricular rhythm disorder (>140 bpm).
• An external pacemaker connected to epicardial electrodes depends on ventricular and atrial pacing.
• Patients already included in an interventional clinical research protocol may alter the incidence of POAF.
• Pregnant woman

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: smartwatches group	Procedure: scanwatch; POAF will be diagnosed with a Withings SM (ScanWatch) by a 1-lead ECG and/or 12-lead ECG.
Active Comparator: no smartwatche group	Procedure: ECG; the POAF will be diagnosed using a 12-lead ECG and according to the usual monitoring protocols for patients in the cardiac surgery department of Amiens University Hospital.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Variation of POAF incidence between both groups	The incidence of POAF will be compared between the two arms	5 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
percentage of asymptomatic POAF in the SW arm		5 days
Association between POAF and left atrial reservoir strain	Left atrial reservoir strain (LASr), measured by transthoracic echocardiography at discharge from the cardiothoracic intensive care unit to the conventional ward, expressed as a percentage (%), and analyzed for its association with POAF (comparison between patients with and without POAF).	At the enrollment in the study (day 0)
Feasibility of rhythm monitoring using a smartwatch	The feasibility of rhythm monitoring using a smartwatch will be assessed by wear time of the smartwatch during the protocol period	5 days
Cardiovascular prognosis assessed by the occurrence of major adverse cardiovascular events (MACE)	Cardiovascular prognosis will be assessed using a composite endpoint of postoperative cardiovascular complications (MACE), defined according to the standards of the European Society of Anaesthesiology (ESA). MACE will be considered present if at least one of the following events occurs: stroke; Myocardial infarction; Digestive ischemia; Unplanned hospitalization for acute right and/or left heart failure decompensation; Resuscitated cardiac arrest and Cardiovascular death. Unit : Frequency of patients experiencing at least one MACE event (percentage, %).	3 months and 6 months after inclusion
Percentage of patients POAF after hospital discharge.	Percentage of patients with POAF after hospital discharge in both groups (with and without smartwatch), assessed at 3 and 6 months after discharge.	3 months and 6 months

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire, Amiens

Study record dates

Study Major Dates

• Study Start (Actual): October 6, 2022
• Primary Completion (Estimated): October 6, 2027
• Study Completion (Estimated): July 6, 2028

Study Registration Dates

• First Submitted: October 6, 2022
• First Submitted That Met QC Criteria: October 6, 2022
• First Posted (Actual): October 10, 2022

Study Record Updates

• Last Update Posted (Actual): February 24, 2026
• Last Update Submitted That Met QC Criteria: February 23, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: cardiac surgery; Atrial Fibrillation; smartwatch; perioperative atrial fibrillation
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Pathological Conditions, Signs and Symptoms; Atrial Fibrillation
• Other Study ID Numbers: PI2021_843_0228

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No