Chief of Pediatric Cardiac Surgery
Director of Pediatric Cardiovascular Services
Mount Sinai Health System
As the father of two children, I can only imagine how overwhelming it feels for expectant parents to hear their obstetrician say, "Your baby may have a heart defect." But it is important for parents to know that this news doesn’t necessarily mean it is a serious problem, and if it is, even babies born with the most complex heart defects can survive to live happy, fulfilling lives, thanks to great advances in the care provided during cardiac surgery and recovery.
How Infant Heart Problems Are Detected
In women who receive comprehensive prenatal care, the overwhelming majority of significant defects are found during a fetal ultrasound test before the baby is born. Those defects missed while the fetus is still in the womb are often discovered through an unusual heart sound, or murmur, after birth. Most murmurs are harmless, but sometimes they indicate structural damage. Rarely, defects may be found two or three days after a child is born, when parents notice that the baby's skin is a little blue, due to low oxygen in the blood (this was more common a few decades ago, before improvements in fetal ultrasound).
Defects Range From Simple to Severe
Congenital heart defects (cardiac disorders present from birth) encompass a broad spectrum. The most common problem is a simple hole between the chambers of the heart. In the majority of cases, the hole will eventually close by itself, without an intervention; it will just require follow-up with a cardiologist. But when parents come to a pediatric cardiovascular surgeon, it usually means the problem is serious, often requiring open-heart surgery.
The most common defects surgeons see require a single operation that can usually be done semi-electively, meaning it doesn't have to be done immediately after birth. These include problems like holes that are too large to close by themselves, and tetralogy of Fallot, which causes oxygen-poor blood to be pumped out to the body. (Awareness of this condition increased greatly after the talk-show host Jimmy Kimmel spoke out about his newborn son’s successful surgery.)
At the far end of the spectrum are more complex structural defects that require a very involved, difficult operation in the first few days of a baby's life (known as the neonatal period), such as transposition of the great arteries, a defect that occurs when the main blood vessels are attached to the wrong chambers of the heart. Some complex defects, like hypoplastic left heart syndrome (HLHS), require at least two more operations over the next several years. HLHS occurs when the left ventricle, which normally pumps oxygen-rich blood to the body, doesn't develop completely. Children with this condition may also require further interventions over the course of their lifetime. Thankfully, the most critical defects are also the rarest, affecting about half a percent of all newborns.
Improved Understanding Means Better Care
The procedures used in complicated neonatal heart operations have not changed much in the last 30 or 40 years. However, there has been enormous progress in outcomes. When some of the most complex newborn operations were first introduced, nine out of 10 children died (still an improvement over the 100-percent mortality rate before the procedures were developed). But today, the rate of successful outcomes has been completely reversed; these same operations have a survival rate of about 90 percent.
What has changed tremendously is our understanding of how both the defects and surgical procedures affect the body’s organs—especially the brain. We are better able to protect children around the time of surgery and manage the post-operative recovery.
During a major open-heart operation, the heart is stopped for a prolonged period, requiring babies to be connected to a machine that takes over for the heart and lungs. Studies in the 1980s and 1990s that looked at the cognitive function of children years after their surgery helped identify what practices were beneficial or detrimental to protecting the brain. We have learned that hypothermia, or low temperature, protects the organs during surgery, but you can cool the brain too much. Over decades, we have determined the safest temperature at which to do certain procedures, as well as the proper flow of blood through the heart-lung machine, and the ideal oxygen levels. Our understanding of the right mix to get patients safely through major operations continues to evolve every day.
Over a similar period, we have learned a lot about how best to manage babies during recovery. The technology used in intensive care units, including ventilators, has improved, allowing more kids to survive through this critical time of recovery from a major heart operation.
Quality of Life
It is natural for parents of a child with a critical heart defect to wonder if he or she will be able to live a “normal” life. The truth is, it depends on the heart defect. With successful surgery for transposition of the great arteries, for example, a baby could grow up and function physically as well as anybody else. On the other hand, some defects, like hypoplastic left heart syndrome, make the heart so structurally abnormal that, despite surgery that allows them to survive, grow, and function, these children will still have limitations. They may be largely indistinguishable from other kids on the playground, but without the reserve capacity of a normal heart, they will never become competitive athletes.
Years ago, I operated on a baby to repair a transposition of the great arteries. I later moved to another area of the country. After more than a decade, I received an email from his father saying the family was coming to my city and wanted to visit me. We had lunch, and I talked with this boy, now 11 years old, who had kept track of my career. It turns out he was on a team of kids who had won a national engineering competition. He got to meet the President of the United States, as well as members of Congress. This boy who had had one of the most complex newborn heart operations was now one of the most accomplished 11-year-olds you could meet.
Heart surgery is not a simple thing, and there are risks. But, today, most kids will survive through even the most serious defects, and grow up to be a source of pride and joy to their parents.