Apple Watch alerts Florida man of A-fib, a condition he didn't know existed

Roy Robinson told ABC News affiliate WPBF that he was on a trip to visit family when a notification reading, "You're in A-fib," popped up on his Apple Watch. Alerts continued to sound about once an hour.

Atrial fibrillation is an irregular heart rate often characterized by rapid beats that can lead to heart failure or stroke.

The first warning was triggered when Robinson found himself out of breath after walking up three flights of stairs at his granddaughter's school, an unusual occurrence as he considers himself fairly fit. Notifications persisted throughout the day, but it was only when Apple Watch sounded an A-fib alarm while he was laying on the couch that he and his family decided to investigate.

"I had no idea what A-fib was," he said.

Following the sixth alert, Robinson conducted a Google search for "A-fib" and, after finishing Thanksgiving dinner, headed to Johns Hopkins Hospital.

"We showed up at the hospital and they said, 'Why are you here?' I says, [. . .] 'My watch says that I'm in A-fib,'" Robinson said. "So he hooks me up to the electrocardiogram and after about 30 seconds of looking at the electrocardiogram, says, 'We're admitting you.'"

A number of doctors, interns, residents and nurses visited Robinson during his time at the facility, saying they wanted to see the "guy that was saved by the Apple Watch."

"I'm not sure if it saved my life, but it sure as hell helped," he said.

Apple Watch has been credited with saving multiple lives since automatic A-fib detection was added to the device's feature set in 2018. The system works by regularly monitoring a user's heart rate data, which is collected by a specialized sensor embedded in the wearable's backside.

Apple continues to build out Apple Watch's suite of health tools, with current iterations of the device boasting a single-lead ECG to better detect irregular heart rhythms.