The heart is, by definition, a hollow, muscular organ that pumps blood through the body through contraction and dilation.

But that is only the beginning of this story, for the heart is also the emotional center of the body. We remember things "by heart." We express our feelings "from the bottom of our heart." Certainly, the heart plays an important part in the Olympics, where athletes can rise to new heights far beyond their usual physical prowess.

Now it's the inspiration for a dance, particularly ironic because heart dysfunction limits the physical activities of those who suffer from heart disease. But it is particularly appropriate in February, not only the month of love and romance because of Valentine's Day, but because it is American Heart Month.

For that reason, Bodiography artistic director and choreographer Maria Caruso chose to debut her full-length ballet, "Heart (Function vs. Emotion)," at the Byham Theater this weekend.

She was drawn into a strange new world when Dennis McNamara, professor of medicine and medical director of heart failure/cardiac transplantation at UPMC, approached her last spring after a concert. Parent of Bodiography apprentice Maggie, he had noticed medical themes in some of her past work.

He suggested that the heart and some of the patients in his program at UPMC could inspire a new ballet. It wasn't long before Ms. Caruso asked for a meeting with them at the company studios in Squirrel Hill.

"But we realized some of them couldn't make it up the stairs to the studio," Dr. McNamara explains. "It was an important occurrence, because it was one of the things that you and I take for granted."

So they switched to the coffee shop across the street, where the patients, along with some of their doctors, packed the house to listen to Ms. Caruso talk about how she wanted to base her ballet on "real" stories and "real" emotions.

She was inviting them to perform in "Heart."

For some the project was still too emotional. Others had logistical problems with work or travel distances. But, in the end, six patients were interested in investing their time in the project.

Soon, Ms. Caruso gave the patients an assignment: "Bring me three physical gestures and three tangible items that are representative of your experience with heart disease." She then brought her company and the patients together. The dancers were to "develop a signature phrase from the patients' material" and Ms. Caruso would incorporate it into the ballet.

The dancers were moved by what they saw and heard. Take Julie Drain, 34, wife and mother of two. She was diagnosed with hypertrophic cardiomyopathy, which she described as "an enlarged heart that doesn't have enough room for the heart muscles to beat," at age 14.

That restricted her from physical activity, including her dream of running cross country. Despite taking care of herself, she had two heart attacks and three strokes before having a defibrillator and pacemaker implanted. Yet Ms. Drain always felt "healthy, not sickly," bouncing back from those problems with no side effects.

Three years ago Ms. Drain was admitted into the UPMC transplant clinic because she was not feeling well. It was a shock. She had never considered a transplant. After weighing all the options and being told that she was a very good candidate by Dr. McNamara, she gave her approval.

Ms. Drain received a new heart on March 4. By day six, she could take 16 steps and was out of the hospital on day nine. Because she wanted to start running, Drain consulted with her transplant physician, Robert Kormos.

She asked him, "What should I do?" He responded, "Start running." She countered, "How far?" He said, "Until you get tired."

Puzzled, she asked, "What do I do?" He said, "Then you stop and run again. It's a muscle -- get it working. You're good to go."

So Ms. Drain bought a pair of running shoes and off she went after 20 years of inactivity. At seven months, she ran her first 5K and started "living the life I've always wanted to."

She also wanted to give back and established her own fund, "Love and Donate Life," to raise awareness and aid patients who are awaiting transplantation. It is supported by fundraisers like her own 5K, called Julie's Jog.

Now Ms. Drain is going on stage, as is Dr. Kormos, director of the artificial heart program at UPMC.

"I like helping," he says modestly.

But the connection goes further than that.

"You know, a lot of the emphasis these days is on the technology," he begins. "People forget that a good portion of this is still an art. A lot of successful physicians and surgeons look at medicine as more than just a science, a job or a profession. They're able to express their creativity -- we just work on a different canvas. And a lot of it is choreography, which Maria saw."

Yes, UPMC arranged for Ms. Caruso to see an actual transplant, which she calls "the most spiritual experience of my entire life." Although Ms. Caruso thought that she would be in an observation deck, the staff outfitted her with green scrubs and stood her on a stool over the patient. She watched as Dr. Christian Burmudez and his assistants operated.

"They took the heart out and held it in front of my face. There was no more ba-boom, ba-boom," she said.

She saw the new heart, white in color, slowly fill with blood. "It just knew what to do," she whispers, still in awe.

So did Ms. Caruso. She centered the first part of her ballet around the function of the heart and the art of dance. It would introduce Cello Fury, playing an original score. The dancers are dressed in red and represent the patients' hearts. They relay patients' movements, like fingers crawling up the wall and shoulder shrugs, representing the anticipation of the operation.

The second half would focus on emotion.

"We're all in this experience together in bringing about awareness," Ms. Caruso emphasizes.

There will be a "frantic section," because patients never know when they're getting a heart. Phil Rosteck, artist and transplant recipient, will translate movements onto a canvas while on stage. And Dr. Kormos will re-create the motions of a surgery.

"I feel like more than a choreographer with this ballet," Ms. Caruso says. "We're all making this journey together. I feel like Julie, who carries her heart wherever she goes."

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