Hand and Heart on Apple Watch Series 4’s ECG App

Apple’s latest watch software update upgrades the heart monitoring capabilities of all Apple Watches and finally lights up Series 4’s Electrocardiogram reader.

Apple Decided to Get Serious About Healthcare

Apple Watch is the Tom Cruise of tech gadgets, always popping up in the news for heroically saving a regular person’s life.

Almost since the Apple Watch launched in 2015, there’ve been stories of the wearable’s built-in heart rate monitor catching irregular heartbeats: A high school senior almost ignores chest and back pain until he noticed that his heart rate was spiking on the Apple Watch. The high school cheerleader and athlete whose Apple Watch alerted her to abnormal spikes and dips in her heart rate and later found out she had a life-threatening kidney condition. The Australian tech journalist whose Apple Watch helped alert him to the fact that his heart was in almost constant atrial fibrillation. There are hundreds (maybe thousands) of stories like these.

This wearable heroism hasn’t gone unnoticed by Apple. Apple CEO Tim Cook often receives emails and letters thanking him. Sometimes he acknowledges them publicly. More importantly, Apple decided to get serious about healthcare, turning the Apple Watch from a best-selling wearable into, with Apple Watch Series 4, an FDA-recognized consumer health device.

In addition to the heart rate sensor on the back, the Apple Watch Series 4 ($399) adds an electrode on the back and another on the digital crown, making it the first-over-the-counter device capable of performing a single-line EKG or electrocardiogram (EKG and ECG are essentially the same thing). However, when Apple debuted the new wearable in September, the watch arrived without software support for either EKGs or irregular heartbeat rhythm notifications.

That changes today. On Wednesday, watchOS 5.1.2 delivers a free software update that will light up both capabilities. Behind them is a year or more of clinical studies designed to prove the Apple Watch’s applicability as a wearable, consumer, medical device.

A year ago, Apple and Stanford University launched a major heart study to learn if the Apple Watch’s pulse detection could also be used for detect heart rhythm disorders. 400,00 people signed up to participate. While the full results of the study won’t appear until next year, smaller Preclinical Studies showed the Watch and its new ECG App has a 98.3% sensitivity in classifying Atrial Fibrillation and 99.6% specificity in classifiable recordings for normal heart activity known as Sinus Rhythm.