CHICAGO (CBS) — A Chicago high school swimmer who almost died from an undiagnosed heart condition wants more people to learn CPR after it saved her life.

About two weeks ago, Claire Luning, who just started her junior year, passed out in the pool during swim team practice.

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“I kind of went fuzzy, and then I don’t really remember what was going on, and I remember grabbing onto the lane line, and people saying my name,” she said.

Her coach, Mack Varilla, said he could tell something was very wrong.

“Instantly, I noticed her skin was flesh pale, eyes wide open, no signs of breathing,” he said.

Varilla performed CPR right away, and doctors at Lurie Children’s Hospital later diagnosed Luning with a heart rhythm disorder. Doctors said she would have died without CPR.

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“I’ve had a lot of time to think in the hospital about what would have happened if Mack hadn’t been there, and if I hadn’t gotten that CPR, because I don’t think anybody else there knew CPR, and it’s just when you realize how important knowing CPR is,” Luning said.

Varilla said the need to know CPR can happen anytime, even among seemingly healthy teens.

“Who knows? It could happen on a football field, or it can happen anywhere,” Varilla said.

A state law enacted last year requires all Illinois high schools to teach CPR and use of automated external defibrillators.

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Payton principal Timothy Devine said they’re working to make sure it’s taught at every grade level, not just to freshmen as it is now.