A young girl in Bridgeport, Connecticut, born with one of the most serious, life-threatening congenital heart defects known, is on her way to living a normal life thanks to Yale doctors who developed and performed the first operation of its kind in the United States.
Angela Irizarry was the first American patient to receive a tissue-engineered blood vessel made of her own natural cells.
Under normal conditions, the heart’s two ventricles collect and pump blood through the body; one sends blood to the lungs where it is mixed with oxygen and the second pumps that oxygenated blood back to the body’s circulatory system.
Angela Irizarry came into the world in November 2007 with one functioning ventricle and the second severely underdeveloped—an often-fatal defect known as hypoplastic left heart syndrome. With one ventricle trying to do the work of two, there is much less oxygen flowing to the body, which is why infants born with this defect are known as “blue babies.” Without surgical intervention, 70 percent die in the first year.
In the past few decades, surgeons have been able to save some children’s lives by implanting synthetic grafts to bypass the second ventricle. “Until now, successfully rearranging the heart’s plumbing required the use of synthetic or man-made materials to create a vascular graft or conduit,” says pediatric surgeon Christopher Breuer, MD.
But synthetic grafts are susceptible to clotting, infection and rejection, and such complications have been the leading cause of postoperative mortality after this surgery. Furthermore, the synthetic grafts can’t grow with the child, he adds.
A graft that would not be rejected
Angela had two synthetic surgeries — one when she was five days old, and the second when she was eight months old. Last summer, she needed a third surgery—just around the time that Dr. Breuer was looking for the right candidate for a new surgery that he had been working on for years. The procedure involved constructing a vascular graft from a patient’s own cells — a graft that would grow with the child and would not be rejected.
Breuer had spent several years researching and then perfecting this surgical technique, working with pediatric cardiac surgeon Toshiharu Shinoka, MD, PhD, who developed the first version of the novel surgery and performed it on two dozen patients in Japan, and a team of Yale biomedical engineers.
Technique uses the patient’s own cells
The technique begins with cells, many of them stem cells, harvested from the patient’s own bone marrow. Those cells are seeded onto a kind of scaffolding to help the cells take the shape of a graft—a new blood vessel made of real tissue from the patient’s own cells. The scaffolding dissolves, and the graft is incubated for just a few hours and then implanted.
The thinking behind the procedure is in line with the expanding field of regenerative medicine, which involves the process of growing or regenerating cells and tissue so that damaged organs can function more normally.
The FDA approved the procedure in November 2009, and Dr. Breuer and his team set out to find their first patient. “We wanted to choose the right patient, but find the right family too,” Dr. Breuer says. “We talked to a number of people but felt the Irizarry family was special. They asked intelligent questions and understood the potential risks and benefits. This was very important to me.”
Surgery went perfectly
Angela’s mother, Claudia Irizarry, was on board from the start. She says, “I always felt positive about this. I believe in God, and that if God would send Angela to us with this condition, that he would protect her. I always believed that everything would be okay.”
Angela’s surgery was scheduled for August of 2011. “We did about 20 practice runs,” Dr. Breuer says. “My lab was more like a track practice than a lab. We timed everything with stopwatches, looking for ways to save every second.”
On the day of the surgery, Dr. Breuer recalls, everything went perfectly. The surgery was performed at Yale-New Haven Children’s Hospital by Dr. Shinoka and pediatric cardiothoracic surgeon Gary Kopf, MD. Dr. Breuer constructed the graft, which was ready within 30 seconds of the time it took in the practice sessions.
As she recovered, Angela had one complication — an infection which was successfully treated but kept her in the hospital for two weeks instead of one. After that was resolved, she came home to complete her recovery. Slowly, she began to do things she couldn’t do before, becoming a normal 3-year-old child who could run around and ride a bike as far as she liked. In November of 2011, Angela celebrated her fourth birthday at home, a healthy little girl who showed all signs of being able to live a normal life.
Angela can’t go to school right away because her immune system is not completely up to par yet (among the other problems with which she was born, she has no spleen), but Dr. Breuer is hopeful that her body will adapt, and that Angela will soon be able to do everything that other kids do.
Her mother says, “Maybe she will be a doctor and help other people they way she was helped.”
For Dr. Breuer and his team, there is great satisfaction. “I fully expect that she will go on to high school and college, and live a happy, healthy life,” he says.
To make an appointment with Yale Pediatric Cardiovascular Surgery, call 203-785-2701.