Apple ECG app and irregular heart rhythm notification are finally launching in Indian for Apple Watch users. From tonight, the feature is live for users of Apple Watch Series 4 with a software update. The new Apple Watch Series 5, which starts selling from September 27, will ship with the features.
What is an ECG?
An electrocardiogram (also called an ECG or EKG) is a test that records the timing and strength of the electrical signals that make the heartbeat. By looking at an ECG, a doctor can gain insights about your heart rhythm and look for irregularities.
How the ECG app works
The ECG app on Apple Watch Series 4 and be used later to generate an ECG that is similar to a single-lead (or Lead I) ECG. If you visit a doctor’s office, a standard 12-lead ECG is usually taken. This 12-lead ECG records electrical signals from different angles in the heart to produce twelve different waveforms. The ECG app on Apple Watch measures a waveform similar to one of those twelve waveforms. A single-lead ECG is able to provide information about heart rate and heart rhythm and enables the classification of AFib. However, a single-lead ECG cannot be used to identify some other conditions, like heart attacks. Single-lead ECGs are often prescribed by doctors for people to wear at home or within the hospital so that the doctor can get a better look at the underlying rate and rhythm of the heart. However, the ECG app on Apple Watch Series 4 or later allows you to generate an ECG similar to a single-lead ECG without a prescription from your doctor.
The results from the ECG app on Apple Watch and from a standard 12-lead ECG taken at the same time were then compared and there was agreement between the ECG app classification of the rhythm as sinus or AFib compared to the standard 12-lead ECG.
The ability of the ECG app to accurately classify an ECG recording into AFib and sinus rhythm was tested in a clinical trial of approximately 600 subjects and demonstrated 99.6% specificity with respect to sinus rhythm classification and 98.3% sensitivity for AFib classification for the classifiable results.
The clinical validation results reflect use in a controlled environment. Real-world use of the ECG app may result in a greater number of strips being deemed inconclusive and not classifiable.
How to use the ECG app
The ECG app is able to record your heartbeat and rhythm using the electrical heart sensor on Apple Watch Series 4 or later and then check the recording for atrial fibrillation (AFib), a form of irregular rhythm.
The ECG app records an electrocardiogram which represents the electrical pulses that make your heartbeat. The ECG app checks these pulses to get your heart rate and see if the upper and lower chambers of your heart are in rhythm. If they’re out of rhythm, that could be AFib.