Singapore Health Sciences Authority has finally approved the use of an ECG app and irregular rhythm notification on Apple Watches. The latest free watchOS 5.3 update will enable you to take an electrocardiogram right from your wrist, capturing heart rhythm in a moment when you experience symptoms like a rapid or skipped heart beat and helping to provide critical data to your physicians.
You are able to identify early signs of AFib, the most common form of irregular rhythm. When left untreated, AFib is one of the leading conditions that can result in stroke, the second most common cause of death around the world.
According to Singapore’s Ministry of Health, AFib, the most common heart rhythm disorder, can affect as many as one in 20 people and is associated with 15 per cent of all strokes in Singapore.
“Having an easily accessible wearable like Apple Watch to detect heart rate, and now heart rhythm with the new ECG app, will go a long way in classifying and eventually managing atrial fibrillation,” said Julian Tan, MD, interventional cardiologist at The Cardiology Practice.
How The ECG App Works?
The ECG App is only available for Apple Watch Series 4. New electrodes built into the back crystal and Digital Crown on Apple Watch Series 4 work together with the ECG app to enable you to take an ECG similar to a single-lead reading. To take an ECG recording at any time or following an irregular rhythm notification, launch the ECG app on Apple Watch Series 4 and hold your finger on the Digital Crown. As you touch the Digital Crown, the circuit is completed and electrical signals across your heart are measured. 30 seconds later, the heart rhythm is classified as either AFib, sinus rhythm or inconclusive. All recordings, their associated classifications and any noted symptoms are stored securely in the Health app on iPhone. You can share a PDF of the results with physicians.
How The Irregular Rhythm Notification Works?
The irregular rhythm notification will be available for Apple Watch Series 1 and later. Using the optical heart sensor in Apple Watch Series 1 or later, the irregular rhythm notification feature will occasionally check your heart rhythm in the background for signs of an irregular heart rhythm that appears to be AFib and alerts you with a notification if an irregular rhythm is detected on five rhythm checks over a minimum of 65 minutes.
To enable these new heart features, you 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 you may get, how to interpret those results and clear instructions for what to do if you are feeling symptoms that require immediate medical attention.
Tried & Tested By Experts
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.
