(NEW YORK) -- Four years ago, Joe Quigley got the call that his 6-year-old daughter, Olivia, had suddenly collapsed at East Boston Central Catholic School after doing gym class warm-ups and running around playing ball with her first-grade classmates.
"You dread getting that phone call from the school. I remember every word," said Quigley, a 52-year-old stay-at-home father by day and a bartender by night. "I knew it wasn't just that she fell over and hurt her leg. It was something serious."
When Quigley arrived at the school, Olivia was lying on the floor surrounded by EMTs. He said the little girl, who had never been ill beyond the "usual coughs and colds," had suffered sudden cardiac arrest.
"At that point, she wasn't even stable enough to be moved," he said. "Initially, we were going to Children's Hospital, but they said this child wouldn't make it that far."
Olivia, who is now 10, survived because her school had a medical emergency response plan, and two teachers had rushed to her side to administer CPR.
The little girl has a healthy heart, but its electrical system is defective. She has catecholaminergic polymorphic ventricular tachycardia or CPVT, which can trigger cardiac arrest.
"It can happen again at any time," said Quigley, who lives with his wife Cathy, Olivia, and 16-year-old son Alex in Winthrop, Mass. "All you can do is be prepared for it."
CPVT is characterized by episodes of fainting without having any structural deformities of the heart, according to Dr. Michael Gewitz, head of cardiology at Maria Fareri Children's Hospital at Westchester Medical Center in Valhalla, N.Y.
"A lot of kids faint at one time in their life," said Gewitz. "The key is if they faint in the midst of either exercise or severe mental stress."
The underlying cause is the onset of fast ventricular tachychardia or arrhythmia. Spontaneous recovery may occur when the arrhythmia stops or it can degenerate into sudden death if cardiopulmonary resuscitation is not readily available.
According to the National Institutes of Health, CPVT is "highly lethal," causing death in 30 percent of all individuals who have had at least one episode and 80 percent of those who have had more spells.
Last year, Massachusetts Gov. Deval Patrick signed a law that requires all schools to have medical emergency response plans.
An estimated 250,000 Americans die each year of sudden cardiac arrest in schools, public places and at home. About 10 percent of all these events occur among people under the age of 40.
"I was completely unaware that her school had a plan," said Quigley. "It's not something I thought to ask, but I am so thankful they did."
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