Validation Study of the Watch HWA09 and Its Softwares ECG-SW1 and PPG-SW1 for the Detection of Atrial Fibrillation

HWA09 is a wrist-worn watch that enables to record a single-lead ECG similar to the standard lead I configuration, and a photoplethysmogram (PPG).

Primary objective :

To validate the diagnostic performance of the ECG-SW1 software integrated into the HWA09 watch for the automatic identification of atrial fibrillation (AF) compared to a simultaneous 12-lead ECG (hereinafter referred to as the "gold standard" or "reference method").

The algorithm classifies the watch signals into four categories: normal sinus rhythm (RSN), AF, arrhythmia other than AF, or non-interpretable. The latter category includes signals of insufficient quality to be interpreted with confidence.

This classification will be compared to the diagnosis made by three independent, blinded cardiologists based on a 12-lead ECG. The final diagnosis retained will be decided by majority with adjudication by a consensus of 3 to 6 cardiologists. The sensitivity and specificity of the device will then be estimated.

First secondary objectives:

The first secondary objective is to validate the diagnostic performance, compared to a simultaneous 12-lead ECG, of the PPG-SW1 software integrated in the HWA09 watch for the automatic identification of atrial fibrillation (AF) from the photoplethysmography (PPG) signal.

Three independent blinded cardiologists will issue a diagnosis based on the ECG recording of the HWA09 watch. The final diagnosis retained will be decided by majority with adjudication by a consensus of 3 to 6 cardiologists. Sensitivity and specificity will be calculated in relation to the reference ECG.

Second secondary objective:

To evaluate the quality of the single-channel strips measured with the HWA09 watch, as follows:

• Three independent cardiologists, having neither performed the data collection nor read the reference ECG, will independently make a diagnosis based on the HWA09 single-channel strips, blinded to the diagnosis made from the reference ECG. The ECG traces from the watch will be exported in PDF format from the Withings Health Mate application and the final diagnosis will be made by majority with adjudication by a consensus of 3 to 6 cardiologists. The final diagnosis will be compared to the diagnosis made by the cardiologists who read the reference ECG. Sensitivity and specificity will then be calculated.
• The visibility and polarity of ECG waves (i.e. P waves, QRS complex and T waves) will be determined by cardiologists for the single-channel strips recorded with HWA09 and for the lead I of the reference 12-lead ECG. For each of the waves, the agreement on their visibility and polarity (if visible) between the HWA09 and the reference ECG will be calculated.
• The durations of the major intervals of an ECG (i.e., QT interval, QRS complex, and PR interval) will be determined by the cardiologists for the single-channel strips recorded with HWA09 and for the lead I of the reference 12-lead ECG. For each interval (QT, QRS, PR), the difference of duration between the signals from the watch and the reference ECG will be calculated.
• The heart rate will first be determined by cardiologists from each signal of lead I (recorded by the HWA09 watch and the reference ECG) that has been diagnosed as NSR. The difference between the heart rate of the watch and the reference will be calculated. In a second step, the heart rate recorded by the HWA09 watch will be calculated by the Withings software. The difference between the heart rate calculated by the Withings software (from the signal of the watch) and the heart rate determined by the cardiologists (from the lead I of the reference ECG) will also be calculated.

The sponsor will ensure that no cardiologist makes a diagnosis on both a signal from the HWA09 watch and the reference ECG fomr the same patient. The sponsor will centralize diagnostics on the HWA09 and reference ECG signals and perform agreement calculations on the associated pairs.