San Francisco, Sep 1 (IANS): Yolie De Leon from US' Arizona said her Apple Watch alerted her to an abnormally high heart rate, sending her to urgent care where she was told by her doctor that her device was right, and her condition was life-threatening.

"It said my heart rate was at 174," De Leon said. "It said, You are an AFib,' and said, Call your doctor immediately.'" She immediately went to the hospital, where doctors ran multiple tests, including an electrocardiogram, reports Apple Insider.

De Leon wanted to show her gratitude to the tech that saved her life - so she reached out to Apple CEO Tim Cook and said she got a surprisingly fast response.

"I'm so glad you sought medical attention and received the treatment you needed," Cook wrote to De Leon. "Thanks for sharing your story with us. It inspires us to keep pushing forward."

The ECG app and irregular heart rhythm notification feature helps users identify signs of AFib, the most common form of irregular rhythm.

When left untreated, AFib is one of the leading conditions that can result in stroke, the second most common cause of death around the world.

The Apple Watch has to date saved many lives across the world via its health features like ECG, Fall Detection and others.

In 2018, Pune-based 53-year-old lawyer Arati Joglekar wrote an email to Cook, thanking him for a "life-changing" moment courtesy her Apple Watch when the wearable kept buzzing him to take deep breath and relieve the stress as her heart rate had shot up to 136 beats per minute.