"It's the worst decision possibly for me to try to make. And it's causing me such stress," McAuley says. "I sleep with it, I wake up with nightmares, anxiety attacks, thinking am I doing the right thing leaving her alone? I'm going in every direction I can before I have to do the surgery."
Twice a year, McAuley takes her daughter to see top cardiologist Dr. Ira Parness at Mount Sinai hospital in New York City. Dr. Parness carefully examines Kay's heart and helps her mom assess the risks of doing nothing versus undergoing open-heart surgery.
"Big operation … long. Let's say three out of 100 patients in Kay's position would die," Dr. Parness explains. "So, I always tell patients that statistics lie. You either escape complication or not. So now, the question is, are you so convinced you need to do this that in the awful, unlikely possibility that she doesn't make it through and she dies, that you can live with that decision?"
Tom and Tonya Preston were also faced with this heartwrenching dilemma. Their daughter Carly was also born with corrected transposition of the great arteries with similar defects. Like Kay, she appeared perfectly healthy. However, unlike Kay, the rest of Carly's organs were in their proper places.
"Initially, they told us she would probably need surgery at 4," says her father, Tom.
So as Carly grew, the Prestons not only got a second opinion, they got a third, and a fourth. And the decision became even more complicated.
"They all wanted to do something different," Tonya Preston said. "So now, you're left weighing not only do we do surgery or not do surgery, but if we do surgery, which one?"
Doctors began to notice that Carly's oxygen level was slowly dropping each year. They told the Prestons it was time for open-heart surgery.
"And it sounds strange," says Tonya Preston, "but I was elated, because I was so tired of thinking about it and not knowing what to do."
The Prestons followed the doctors' advice and Carly went through open-heart surgery at age 7. To find out how Carly fared in surgery, watch "Primetime: Medical Mysteries."
Since Kay's heart is still working quite well, McAuley has decided not to proceed with an operation… right now. But she is still consumed with indecision because she knows her daughter's chances of a good recovery are much better while she's young.
Meanwhile, McAuley has become a CPR instructor and advocate. She also tries to use her skills and expertise to help raise awareness about congenital heart defects and plans to begin a fund for Kay's future operation.
Carly Preston's surgery lasted about five hours. During that time, a specialist was able to re-reroute her blood flow to mimic a normal heart. And a bypass machine took over pumping her blood while her problematic valve was replaced with an artificial one.
That was about three years ago. Today, Carly is as active as most other 10-year-olds. She runs, jumps and performs ballet. But she still remembers waking up after the surgery.
"I was sore," Carly says. "And when I saw my stitches and stuff, I was kind of like, wow. I couldn't walk for a long time because all my muscles were used to lying down."
Since her doctor had to replace one of her valves with an artificial one, Carly will have to undergo more surgeries as she gets older.