A surburban Atlanta man is crediting his fitness watch with saving his life.

>> Read more trending news

DeKalb County resident David Gilley is recovering from heart surgery, and said he's alive because of his watch.

“I heard a beeping sound and looked down and said, 'Hmm, I’ve never seen that message before,'” Gilley said.

The Apple Watch told him his heart was racing more than 140 beats per minute.

“It saved my life on March 2,” Gilley said.

Gilley’s wife rushed him to a hospital.

"If I had not had the watch on, I would have gone to bed and no telling what would have happened then," Gilley said.

Millions of people have fitness trackers.

Dr. Anshul Patel, a heart rhythm specialist with Emory’s St. Joseph Hospital said that he uses fitness trackers to keep up with patients.

“What I’d like people to use it for is general trends to see what their heart rate is doing,” Patel said.

If you see a spike into high numbers but feel OK, Patel advised calling your doctor.

“Maybe notice there could be an issue, but we always like to confirm there might be a problem,” Patel said.

If you feel dizziness, chest pains, or have a medical history like Gilley, call 911 or go to the emergency room.

“I have hope I’ve got a great medical team,” Patel said. "Apple did a good job but God’s got control.”

Gilley’s watch was a birthday present from his wife.

"Now, there's the potential to have many more birthdays. What a great gift," Gilley said.