Consumer Wearables and Care of the Arrhythmia Patient
Companion Guide for HRS Presentation
This post contains a summary of information and resources presented at HRS in the FIT Lounge (sponsored by iRhythm). It is meant to serve as a reference for practicing physicians and fellows, as well as all those interested and wearable tech.
Irregular Rhythm Algorithm Specs
Apple has released the most information about the inner workings of their Irregular Rhythm Notification algorithm (found in their FDA filing), followed by Google (FitBit). There is much less information publicly available regarding Samsung’s algorithm. They all monitor heart rate in the background and check for irregularity via tachograms. Apple attempts to monitor every two hours (if the person is at rest), while Google and Samsung say they simply monitor ‘intermittently throughout the day.’ Once an irregular tachogram is detected they switch modes and begin to monitor more frequently (all at variable intervals). I have collected the available details below:
Note: None of the algorithms will run when the user is active (accelerometer is activated) due to known inaccuracies caused by PPG noise.
Irregular Rhythm Monitoring Diagnostic Metrics:
ECG Diagnostic Metrics, from BASEL Wearable Study:
Link to source: BASEL Wearable Study
Deep Dive on Apple Arrhythmia Tools: Clinical Uses of the Apple Watch
Atrial Fibrillation vs Consumer Tech: SMART Wars
Devices with FDA approved rhythm monitoring features:
Apple Watch (AW):
ECG feature: all current devices, except AW SE
Irregular rhythm notification (IRN): all current devices, including AW SE
AF History: all current devices, including AW SE
Samsung Watch (SW):
ECG feature: all numbered Galaxy models, Ultra and FE, not FIT
IRN: all numbered Galaxy models, Ultra and FE, not FIT
Google FitBit (FB) and Pixel Watch (PW):
ECG feature: all PW models, FB Sense, FB Sense 2, FB Charge 6 and FB Charge 5
IRN: Pixel Watch (model 2 and 3 only), FB Sense 2, FB Sense, FB Versa 4, FB Versa 3, FB Versa 2, FB Versa Lite, FB Charge 6, FB Charge 5, FB Charge 4, FB Charge 3, FB Luxe, FB Inspire 3 and FB Inspire 2
AliveCor Kardia Devices (KM):
ECG feature: KM, KM 6-lead, KM Card
KardiaCare subscription: advanced ECG algorithm for PVCs, PACs as well as limited remote review of ECG by a board-certified Cardiologist
Other devices with FDA cleared ECG algorithms :
Withings ScanWatch
Garmin: epix Pro series, fēnix 7 Pro series, Venu 3 series and tactix 7 – AMOLED Edition
Circular Ring 2
Medical Grade Ambulatory ECG Device Comparison:
Link to source: Ambulatory ECG Devices
Useful Links and Sources:
Apple FDA Filings:
Samsung FDA Filings:
Google FDA Filings:
Clinical Trials and Review Articles:
Wearable Digital Health Technologies for Monitoring in Cardiovascular Medicine - NEJM
HRS White Paper on Clinical Utilization of Digital Health Technology
State of the Art of Mobile Health Technologies use in Clinical Arrhythmia Care - Nature