"In hypoplastic left heart syndrome (HLHS), babies are born basically missing the left side of their heart and would die within the week without treatment," said Dr. Bacha, surgical director of the Congenital Heart Center at the University of Chicago. "The heart's main pumping chamber, the left ventricle, and the body's primary blood vessel, the aorta, are not properly formed. As a result, the heart is unable to pump blood effectively to the body."
"Approximately one percent of babies are born with some kind of heart abnormality, which can range from very minor to very serious," said Dr. Bacha "HLHS accounts for 7 to 9 percent of all congenital heart disease diagnosed in the first year of life."
Dr. Bacha spoke today at the AMA's 23rd Annual Science Reporters Conference in Washington, D.C.
The standard treatment for these infants has been a series of three open-heart surgeries – the first one (called the Norwood after the surgeon who developed it) is performed within the first few days of life. Additional open-heart surgeries are conducted at approximately six months and two years of age. The new approach being pioneered by Dr. Bacha and Dr. Hijazi eliminate the initial open-heart surgery, which carries the greatest risk of serious side effects and death.
"The initial surgery has roughly a 20 percent mortality rate," Dr. Bacha said. "This is a very dangerous surgery for these tiny infants. We have to put them on cardio-pulmonary bypass, cool the patient and do deep hypothermic circulatory arrest. On a five or six day old, who may be premature, it's not surprising that the outcomes in terms of the brain are not very good."
"Although approximately 80 percent of these infants survive the initial surgery, we want to be sure that they survive with a good quality of life," Dr. Bacha said. "Our new hybrid procedure doesn't require the heart-lung machine or stopping the infant's heart. This reduces the risk of neurological damage."
The new procedure is conducted in a catherization lab, rather than an operating room. The chest is opened briefly to gain access to the heart and the pulmonary arteries (vessels going from the heart to each lung). Through small openings, Dr. Bacha's team places restrictive bands around these vessels to narrow them, restricting blood flow to the lungs. Next, Dr. Hijazi and Dr. Bacha work together to deploy a stent, a narrow tube that allows blood pumped by the right side of the heart to flow into the aorta and out to the child's small body.
This combination of less-invasive measures buys time, enables the child to survive without a massive operation soon after birth and allows the child to grow for several months, which makes the follow-up operations easier, according to Dr. Bacha. The University of Chicago is one of a few hospitals in the United States using hybrid surgery to treat HLHS.
"Initially, we were only doing hybrids on high-risk patients and using the standard method for the low-risk cases," Dr. Bacha said. "But the hybrid technique has proved so successful that it has replaced the traditional method for use with newborns at the University of Chicago Children's Hospital. Using our new hybrid technique, we have a better chance of achieving our goal of having a child who can live a normal active life following these three procedures."
To contact Emile Bacha, M.D., contact John Easton at 773-702-6241 or at jeaston@uchospitals.edu.