Is the New ECG Feature on the Apple Watch Series 4 Useful?

Last month, Apple released the Apple Watch Series 4 with a brand new ECG, or electrocardiogram, feature. Since the release there have been opposing opinions about whether this is a useful, or beneficial feature for users. Doctors and tech experts alike have weighed in on the topic and the answer is still unclear. In fact, even Health Canada hasn’t approved the feature in Canada. So, is the new ECG feature on the Apple Watch useful?


What is an ECG?

To determine whether the ECG feature on the new Apple Watch Series 4 is beneficial, it’s important to start by understanding what an ECG is. An ECG measures the electrical activity of your heartbeat. Using an ECG, a doctor can look at the rhythm and speed of this electrical activity. This can reveal irregular heart rhythms (or arrhythmias), cardiac arrest, atrial fibrillations (a marker of a stroke) and other heart dysfunction.


Performed by a medical professional, an ECG typically has 12 leads with electrodes that are attached all over the body to measure heart signals from a variety of angles. However, some portable ECG machines, designed to be worn by patients outside of formal medical settings, have just one lead and provide a single view.


The argument against ECG on the Apple Watch

While an ECG provides valuable information about heart function, the ECG functionality on the Apple Watch Series 4 has its limitations. For example, the Watch has a single lead while traditional ECG monitors used by doctors and hospitals use a total of 12 leads. As you can imagine, this means that the Apple Watch offers a much narrower view of what’s happening with a patient’s heart. There’s also the question of the accuracy of a product designed for consumers versus one designed for medical professionals. Finally, there’s the matter of user error. After all, an ECG test is typically performed by a highly trained medical professional while the Apple Watch will be used by consumers with little to no training. In fact, Apple recommends that users rest their arms on a table or their legs while measuring their heart rhythm using the ECG function. This means that movement can affect the results of the ECG measured by the Watch, leaving a lot of room for error.


The argument for ECG on the Apple Watch

While the precision and accuracy of ECG monitoring in the new Apple Watch Series 4 may be in question, the data collected by the device is still valuable. For starters, the ECG function in the Watch Series 4 can expose changes in heart rhythm in patients, especially changes that can’t necessarily be recreated at the doctor’s office. This data can be easily shared with medical professionals who can investigate whether these changes are cause for concern. In addition, this data can provide medical professionals and researchers with a volume of ECG data that has never been available before. This data can give them insight into patterns in populations, those among people taking similar drugs, and those among people with similar conditions or lifestyles.


Bottom Line

Will the ECG feature on the new Apple Watch Series 4 be able to diagnose heart conditions? No, of course not—only a medical professional can do this! In fact, the ECG feature might not even provide 100% complete or accurate data. That being said, the data can offer health professionals valuable insight into changes in a patient’s heart rhythm while also offering a volume of data never before available. While this feature is still not available in Canada, I’m confident that Health Canada will approve the feature in the future. In addition, I expect to see other consumer devices follow Apple’s lead with their own ECG features in the near future.

By Mike Agerbo

October 16, 2018