Apple Watch Series 4 has two FDA-purified heart functions that can warn of life-threatening conditions. Here it happened when Vanessa Hand Orellana tested Apple's ECG against a medical grade ECG.
Vanessa Hand Orellana for CNET:
When I first started testing the ECG function on Apple Watch Series 4 – launched in December with the update to Watch OS 5.1.2 – the last thing I expected was finding something abnormal at my heart rhythm. But that was exactly what happened when I cross-referenced Watch's readings with medical grade ECG equipment at the doctor's office. "We look at your Apple Watch the same early heartbeat as we see on the ECG," said Dr. Gregory Marcus, a professor of medicine and cardiac electrophysiologist at UCSF Medical Center, as I was sitting on the hospital bed with cables attached to my body and an Apple Watch Series 4 on my wrist …
An ECG uses electrodes to measure heart electrical activity. ECGs in hospitals generally consist of 10 electrodes located on different parts of your body. Apple Watch Series 4 has two: an electrode on the back and an electrode on the digital crown.
When he looked at his screen, I opened the new ECG app (Apple uses the abbreviation ECG, while doctors generally say the ECG) on the Apple Watch Series 4 to take my first ECG. I put my finger on the digital crown and waited while the screen counted down 30 seconds … The ECG on Apple Watch fell directly with the results of the printed hospital ECG.
MacDailyNews Take: Wearing an Apple Watch Series 4 can save your life!