Take an ECG with the ECG app on Bearscome Watch

An electrocardiogram (also called an ECG or EKG) is a test that records the timing and strength of the electrical signals that make the heart beat. By looking at an ECG, a doctor can gain insights about your heart rhythm and look for irregularities.

The ECG app can record your heartbeat and rhythm using the electrical heart sensor on Apple Watch Series 4 or later and all models of Apple Watch Ultra* 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 heart beat. 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.

You can take an ECG at any time, when you’re feeling symptoms such as a rapid or skipped heartbeat, when you have other general concerns about your heart health, or when you receive an irregular rhythm notification.

1. Make sure that your Watch is snug and on the wrist that you selected in the app. To check, open the app, tap the My Watch tab, then go to General > Watch Orientation.
2. Open the ECG app on your Watch.
3. Rest your arms on a table or in your lap.
4. With the hand opposite your watch, hold your finger on the Digital Crown. You don't need to press the Digital Crown during the session.
5. Wait. The recording takes 30 seconds. At the end of the recording, you will receive a classification, then you can tap Add Symptoms and choose your symptoms.
6. Tap Save to note any symptoms, then tap Done.

After a successful reading, you will receive one of the following type of results on your ECG app. Regardless of the result, if you aren't feeling well or are experiencing any symptoms, you should talk to your doctor.

Sinus rhythm

A sinus rhythm result means the heart is beating in a uniform pattern between 50 and 100 BPM. This happens when the upper and lower chambers of the heart are beating in sync. A sinus rhythm result only applies to that particular recording and doesn’t mean your heart beats with a consistent pattern all the time. It also does not mean that you're healthy. If you're not feeling well or are feeling any symptoms, you should talk to your doctor.

Atrial fibrillation

An AFib result means the heart is beating in an irregular pattern. AFib is the most common form of serious arrhythmia, or  irregular heart rhythm. If you receive an AFib classification and you have not been diagnosed with AFib, you should talk to your doctor. The ECG app ver. 1 can check for AFib between 50 and 120 BPM. The ECG app ver. 2 can check for AFib between 50 and 150 BPM.

Low or high heart rate

A heart rate under 50 BPM or over 120 BPM in ECG version 1 affects the ECG app’s ability to check for AFib. In ECG version 2, a heart rate under 50 BPM or over 150 BPM can affect the ECG app's ability to check for AFib.

• A heart rate can be low because of certain medications or if electrical signals are not properly conducted through the heart. Training to be an elite athlete can also lead to a low heart rate.
• A high heart rate could be due to exercise, stress, nervousness, alcohol, dehydration, infection, AFib, or other arrhythmia.

Inconclusive

An inconclusive result means the recording can’t be classified. It could be due to one of the following situations:

• In ECG version 1, your heart rate is between 100 and 120 BPM and you are not in AFib.
• You have a pacemaker or implantable cardioverter defibrillator (ICD).
• The recording may show signs of other arrhythmias or heart conditions that the app is not designed to recognize.
• Certain physiological conditions may prevent a small percentage of users from creating enough signal to produce a good recording.

The ECG waveform, its associated classifications, and any noted symptoms will be saved in the Health app on your phone. You can also share a PDF with your doctor.

1. Rest your arms on a table or in your lap while you take a recording. Try to relax and not move too much.
2. Make sure that your Watch isn’t loose on your wrist.
3. The band should be snug, and the back of your Watch needs to be touching your wrist.
4. Make sure that your wrist and your Watch are clean and dry.Make sure that your Watch is on the wrist that you selected in the Watch app. To check, open the Watch app, tap the My Watch tab, then go to General > Watch Orientation.
5. Move away from any electronics that are plugged into an outlet to avoid electrical interference.
A small percentage of people may have certain physiological conditions preventing the creation of enough signal to produce a good recording — for example, the positioning of the heart in the chest can change the electrical signal levels, which could impact the ECG app’s ability to obtain a measurement.
Liquid-free contact is required for the ECG app to work properly. Use of the ECG app may be impacted if the Watch and/or skin aren't entirely dry. Make sure that your wrist and hands are thoroughly dry before attempting a reading. 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 Watch to completely dry.

The ECG app on Watch generates an ECG that is similar to a single-lead (or Lead I) ECG. In 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 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. 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.In studies comparing the ECG app on 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.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.