(NEW YORK) -- No one believed Wenter Blair was having a heart attack -- the 40-year-old ranch photographer from Frisco, Texas, was just too healthy.
Blair had been referred for a nuclear stress test after she had an incident of chest pressure and sweated profusely. But as she ran on the treadmill, a bit short of breath but in no pain, the doctor dismissed the results as a "false positive."
"When you see a 128-pound, 5-foot 4-inch woman in stilettos, doctors think it's a hormone issue," said Wenter, now 44. "I was riding horses, chasing children, swimming -- I live a very active life. I ran a 10K the week of my heart attack."
But a nurse who was monitoring the results recognized it was, indeed, a heart attack and pushed Blair to get herself to another doctor, saving her life -- and, surprisingly, the life of her then 9-year-old son.
Blair was diagnosed with familial hypercholesterolemia -- a lipid disorder that starts at birth, causing an elevation of fat in the blood and leading to heart disease, stroke and other medical problems. And when genetic tests were done, they discovered her son Christian also had the condition.
With, FH, heart disease and heart attacks can occur at a young age. People with a severe form of this condition can die in their 20s.
"The tragedy of it was it was only diagnosed because of a wonderful, crazy, God-like intervention and series of events," said Blair. "Doctors watched my heart attack and didn't think it was real."
Now, she wants others to know about the disease so that their children can be tested and treated early, before damage sets in.
The American Academy of Pediatrics now recommends cholesterol testing for all children once between the ages of 9 and 11, in large part to detect familial hypercholesterolemia, according to ABC's Dr. Richard Besser.
"While this is somewhat controversial, if your child hasn't been screened, ask about this," he said.
For many people, abnormal cholesterol levels are partly due to an unhealthy lifestyle, such as eating a diet that is high in fat. But in Blair and her son's case, high levels of LDL -- the so-called "bad cholesterol -- were genetic.
About one in 500 Americans has familial hypercholesterolemia or FH, but many more go undiagnosed, according to Dr. James Underwood, a clinical lipidologist at the NYU Center for Cardiovascular Disease Prevention. There is also a higher risk among Ashkenazi Jews, French Canadians, Christian Lebanese and South African Afrikaners.
Blair finally got a proper diagnosis and, after quadruple bypass surgery and 10 stents around her heart, she is on medication. Her son Christian, too, is being treated.
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