I've shrugged off the idea of wearing a fitness-focused smartwatch, questioning their accuracy, but a story out of Tampa Bay, FL shattered my stance. That's because an Apple Watch alerted a teenager of a sharp rise in her resting heart rate, which revealed an even bigger medical situation.

(Image credit: Shaun Lucas/Tom's Guide)

This news comes from WFTS Tampa Bay News, which reported how 18-year-old Deanna Recktenwald's Apple Watch alerted her that her resting heart rate hit 190 beats per minute (well above the 40 to 100 bpm rates that the Mayo Clinic classifies as normal). The alerts appeared "out of the blue" while Deanna was at church, and she had no idea of her condition.

Stacey Recktenwald, Deanna's mother, wrote a letter to Apple, thanking the company for making the health-minded wearable. In her letter, we learn that the notification prompted Deanna to seek emergency care, where doctors discovered that her kidneys "were only functioning at 20 [percent]," despite "no symptoms of any kidney issues or any other medical issues."

Deanna's about to head off to college this August, and her doctors noted that she'd have needed a kidney transplant while away, had her condition gone further undiagnosed. The Apple Watch is giving Stacey is a bit of relief, knowing that she can send Ashley "off to college and know that she can monitor her HR and seek attention if it alarms her again."

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Stacey, a registered nurse, told the local news network that she wasn't aware of the Apple Watch's ability to send such an alert, and while she didn't initially trust the accuracy at first, she was "surprised, it was right on." The doctors at Tampa General Hospital diagnosed Deanna with chronic kidney disease.

Apple CEO Tim Cook responded to Stacey's email, thanking her for sharing the story, and saying "This inspires us to keep pushing."

This past March, news broke of a study that demonstrated how the Apple Watch can detect irregular heart rhythms as accurately as an electrocardiogram.