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In studies comparing the ECG app on Apple Watch to a standard 12-lead ECG taken at the same time, there was agreement between the ECG app classification of the rhythm as sinus or AFib compared to the standard 12-lead ECG. 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, Series 5, Series 6, or Series 7 allows you to generate an ECG similar to a single-lead ECG without a prescription from your doctor. However, a single-lead ECG cannot be used to identify some other conditions, like heart attacks. 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 classification of AFib.
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This 12-lead ECG records electrical signals from different angles in the heart to produce twelve different waveforms. In a doctor’s office, a standard 12-lead ECG is usually taken. The ECG app on Apple Watch Series 4, Series 5, Series 6, Series 7, Series 8, or Ultra generates an ECG that is similar to a single-lead (or Lead I) ECG. To ensure the best reading after swimming, showering, heavy perspiration, or washing your hands, clean and dry your Apple Watch. It may take one hour or more for your Apple Watch to completely dry. Make sure that your wrist and hands are thoroughly dry before attempting a reading. Use of the ECG app may be impacted if the Apple Watch and/or skin aren't entirely dry.
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Liquid-free contact is required for the ECG app to work properly.
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