Apple Watch ECG heart sensor again credited for life-saving alerts

David Last, 54, was given the Apple Watch by His wife, Sarah for his birthday back in April. Soon after wearing it, the electrocardiogram feature (ECG) started giving him alerts for a low resting heart rate on almost 3,000 separate occurrences.

For an adult male, the average resting heart rate is typically 60 to 100bpm. Last's rate dropped as low as 30bpm. Due to the large number of alerts, he assumed the Apple Watch was buggy. He described himself as leading an active lifestyle with no family history of heart complications.

However, eventually his wife persuaded him to visit the doctor, who then referred him to a cardiologist.

After an MRI scan in May with results arriving in July, his consultant gave him a 48-hour ECG to monitor his heart rate. Last said he finally realized there was a problem when people from the hospital sounded "really panicky" on the phone.

"As soon as I got there, they had a bed ready," Last said.

The available bed was just in time, as doctors told him he had a third-degree heart blockage because a junction in his heart was wearing away. The risk of this progressing is sudden cardiac death.

His heart stopped 138 times in 10-second intervals over a 48-hour period, mostly happening during sleep. Other parts of his heart had to take over to resume blood flow before the problem started over again.

In August, Last received surgery and received a pacemaker to detect abnormal rhythms and help each heart ventricle pump blood in sync, as a healthy heart does.

"If she hadn't bought me my Apple watch for my birthday, I wouldn't be here," Last said. "I will always be eternally grateful to her for it. Apart from charging it, it's always staying on me now."

An electrical heart sensor for taking an ECG is available on the Apple Watch Series 4, Apple Watch Series 5, Apple Watch Series 6, and Apple Watch Series 7.