How (and when) to use Apple Watch ECG feature


Apple health care
Apple's health-tracking features have been a game changer.
Photo: Lewis Wallace/Cult of Mac

watchOS 5.1.2 launched to the public this morning and finally activated the ECG feature on Apple Watch Series 4.

For now, the ECG app can only be used in the US and US territories, but it gives wearers the ability to take an electrocardiogram to see whether your heart rhythm shows signs of atrial fibrillation. Using the ECG only takes about 30 seconds and it could save your life.

Here’s how to master the ECG:

For now, only Apple Watch Series 4 units that were purchased in the U.S. will be able to activate the ECG app. Your iPhone must be running the release version of iOS 12.1.1.

You can take an ECG anytime you want to. When you’re feeling symptoms such as a rapid or skipped a heartbeat, when you have other general concerns about your heart health, or when you receive an irregular rhythm notification, just pull up the ECG app.

Hands-on with Apple Watch ECG app

Using the ECG app couldn’t be simpler. After upgrading to watchOS 5.1.2, you just need to set up the ECG app in Apple’s Health app. That involves nothing more than adding your birthdate and running you through a quick overview of what the app measures.

You’ll get a brief primer of the types of readings possible: Sinus rhythm, Atrial fibrillation, Low or high heart rate, or Inconclusive. (Hint: Sinus rhythm is the one you want.) Apple also takes this opportunity to issue some caveats about the device’s limitations and warnings about seeking help if you’re experiencing a medical emergency.

After that, you just pull up the ECG app on your Apple Watch, gaze briefly at the dancing dots of the heart-shaped icon, then place a finger on the Digital Crown. A 30-second countdown timer starts, with your heart rate and a visual representation of your heart rhythm displayed. (You’ll also see yet another caveat: “Note: Apple Watch never checks for heart attacks.”)

If you’re not feeling well, you can tap the + Add symptoms and scroll through a list of symptoms like shortness of breath and fatigue. Select the relevant symptoms to log, then tap Done to store your reading.

All in all, it’s an unbelievably quick and easy way to get a basic electrocardiogram reading. From setup to running the first ECG, it shouldn’t take more than a couple of minutes.

Setting up the app

Before you can use the ECG you need to set up the app on your Apple Watch. Make sure to download watchOS 5.1.2 from the Watch app on your iPhone. Once its installed follow these steps:

  • Open the Health app on your iPhone.
  • Follow the onscreen steps.
  • If you don’t see a prompt to set up, tap Health Data > Heart > Electrocardiogram (ECG).
  • After you set up ECG in the Health app, the ECG app appears on your Apple Watch.

Using the ECG

It only takes 30 seconds to get your ECG reading.
Photo: Apple

Once you have your Apple Watch up-to-date, make sure that it is snug and on the correct wrist selected in your Apple Watch app. Now do the following:

  • Open the ECG app on your Apple Watch.
  • Rest your arms on a table or in your lap.
  • 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.
  • 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.
  • Tap Save to note any symptoms, then tap Done.

— Additional reporting by Lewis Wallace


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