LITHIA, Fla. — A Tampa Bay teenager is thankful for the device on her wrist after suffering a scary medical episode at The Crossing Church in Brandon.

"I didn't know what was going on at all and it was just out of the blue," said Deanna Recktenwald.

A warning appeared notifying the 18-year-old that her resting heart rate hit 190 beats per minute.

"It was alarming that the watch was telling us to seek medical attention," said Stacey Recktenwald, Deanna's mother. "I didn't even know that it had the capability of giving us that alert."

Stacey Recktenwald is a registered nurse and did not initially question the accuracy of the watch's reading.

Staff at a walk-in clinic confirmed the teen's rapid heartbeat.

"I was surprised, it was right on," said Stacey.

The Recktenwald's all agree that the watch saved Deanna's life.

After rushing her to the emergency room, doctors at Tampa General Hospital soon discovered Deanna suffers from chronic kidney disease.

Both kidneys are only operating at 20% and she will likely require a future transplant.

"Instantly started to pray and thank God for her having that watch," said Tom Recktenwald, Deanna's father.

The high-tech Christmas gift came to the rescue, uncovering a serious health problem that would have otherwise gone unnoticed.

"Now that we have some answers to why this is happening we can prevent something major from happening down the road," said Deanna.

Stacey Recktenwald recently wrote Apple to thank the tech giant for its life-saving feature.

CEO Tim Cook responded by thanking the Lithia family for sharing their story.