The Gentleman Magazine Issue 14 | April 2019 | Page 77
Irregular Rhythm Notification
Using the optical heart sensor in Apple Watch Series 1 or later,
the irregular rhythm notification feature will occasionally
check the user’s heart rhythm in the background for signs of an
irregular heart rhythm that appears to be AFib and alerts the
user with a notification if an irregular rhythm is detected on
five rhythm checks over a minimum of 65 minutes.
“It is exciting to see the potential of Apple Watch to provide
an earlier indication of potential heart rhythm issues. Today,
there are around 1.5 million people in the UK living with
atrial fibrillation, the most common heart rhythm problem,
but a third of these people may be unaware of this. An on-
demand pulse check and ECG could be a powerful tool in our
ongoing quest to manage heart health better across Europe.
The opportunity for innovation to optimise patient care is huge
and this is a great step forward,” said Professor Martin Cowie,
professor of Cardiology at Imperial College London based
at Royal Brompton Hospital, and chair of the Digital Health
Committee of the European Society of Cardiology.
The ECG app’s ability to accurately classify an ECG recording
into AFib and sinus rhythm was validated in a clinical trial of
around 600 participants. Rhythm classification from a gold
standard 12-lead ECG by a cardiologist was compared to the
rhythm classification of a simultaneously collected ECG from
the ECG app. The study found the ECG app on Apple Watch
demonstrated 98.3 percent sensitivity in classifying AFib
and 99.6 percent specificity in classifying sinus rhythm in
classifiable recordings. In the study, 87.8 percent of recordings
could be classified by the ECG app.
The irregular rhythm notification feature was recently studied
in the Apple Heart Study. With over 400,000 participants, the
Apple Heart Study was the largest screening study on atrial
fibrillation ever conducted, also making it one of the largest
cardiovascular trials to date. A subset of the data from the Apple
Heart Study was submitted to the FDA to support clearance of
the irregular rhythm notification feature. In that sub-study, of
the participants that received an irregular rhythm notification
on their Apple Watch while simultaneously wearing an ECG
patch, 80 percent showed AFib on the ECG patch and 98
percent showed AFib or other clinically relevant arrhythmias.
To enable these new heart features, customers will be taken
through an onscreen setup flow that includes details about who
can use these features, what the features can and cannot do,
what results users may get, how to interpret those results and
clear instructions for what to do if users are feeling symptoms
that require immediate medical attention.
watchOS 5.2 is now available for download.