What Astronauts Have Taught Doctors About Fainting

                                                                                                   (Image Credit: Getty Images)

ABC News' Andrea Canning Reports: 

Kathy Chandler is a chronic fainter, but NASA research on astronauts could provide clues to keeping her healthy.

"Astronauts are very prone to fainting, dizziness," Dr. Fred Jaeger of the Cleveland Clinic told ABC News. "If you are in space you are not using all of your muscles, including your heart, because you don't have gravity to fight. And so their heart size was decreasing."

One such fainting attack struck astronaut  Heidemarie Stefanyshyn, who collapsed after returning from her first space mission.

The fainting and dizziness symptoms can be shared by patients like Chandler who have a condition called postural orthostatic tachycardia syndrome or POTS. POTS affects up to one million people, most of them women.

"The hallmark of POTS is the high heart rate," said Jaeger. "The high heart rate can trigger fainting."

Doctors try to keep patients with POTS healthy by adjusting their diets and helping them change how they sleep, but it is NASA researchers who came up with a tailored exercise program that is now being used not only on astronauts, but on patients with POTS.

The exercise program is intended to help the heart grow in some patients and in others to condition the heart muscle and prevent fainting.

"It involves exercises that avoid gravity," Jaeger said. "And for the first time ever we actually have a way to turn around the person's symptoms and actually cure them."

While prescriptions for POTS patients vary, for Chandler she is currently focusing on eating salty food to keep her blood pressure up, tilting her bed when she sleeps to keep her blood flowing, taking medication to control her heart rate and exercising on a recumbent bike.

"I will be using that more often now to build up my heart muscle. I want to be at my best.

Chandler hopes soon to be free of fainting, thanks to a little help from "The Right Stuff."