One morning, when 25-year-old Jessica Martineau, a devoted professional dancer, performed a particularly difficult piece on stage, her heart began to race. And then she collapsed.
"I felt myself flying to the floor. At that point, you know, obviously, everything went black," the Michigan dancer, now 32, recalled in an interview with "Good Morning America."
Doctors who treated Martineau after the collapse were baffled as to its cause, until they examined her heart rhythms and found that she had Long QT syndrome -- a hereditary disorder of the heart's electrical system that causes the organ to malfunction, sending the person into cardiac arrest at any time.
For Martineau, the news was devastating, both personally and professionally.
Her doctors advised her to stop dancing and get a defibrillator implanted inside her chest. If her heart stopped, the device, an implantable cardioverter defibrillator, or ICD, would automatically deliver a shock to get the organ restarted.
Martineau refused both medical recommendations.
"For me, personally, it's not the right choice," Martineau said. "I don't want to live like a robot. I don't want to live with a titanium box in my chest. ... I would rather live with the risk of this disease, of having another episode."
Doctors put her on medication, and she continued to dance. Although she didn't have any pain or discomfort, she remained anxious over when her next episode could occur.
"Dance has always been such a natural, beautiful expression for me. And it's where I find my community and my friends, and it's how I relate to the world," she said. "I'm not sure what I'm going to do when those days are over."
A major factor in that worry was that Martineau never knew how severe her case was.
Long QT syndrome may be caused by one of three separate genetic defects, including one type that is far less severe than the others.
Last month Martineau underwent a new genetic test -- a simple blood test -- at the NYU Langone Medical Center after which Dr. Silvia Priori revealed that Martineau had the least risky of all causes of the disorder.
The cutting-edge blood test provides an invaluable, more affordable look at how the disorder affects individuals.
As a result, Martineau should respond well to medication, and her cardiac episodes most likely won't be deadly, although she still lives in danger.
For example, her doctors said Martineau should never swim alone again.
For the dancer, who was adamantly against having the ICD implanted, the results were a relief.
"I'm so glad that these tests exist and people can get this kind of information," she said.