Pediatric cardiology is the branch of medicine focused on diagnosing and treating heart problems in children, from before birth through young adulthood. The specialty covers both structural heart defects that babies are born with and heart conditions that develop later in childhood. About 1% of babies born in the United States, roughly 40,000 per year, have some form of congenital heart defect, making this one of the most common types of birth defects.
What Pediatric Cardiologists Actually Do
Pediatric cardiologists care for patients from fetal life through adulthood. Their work ranges from evaluating a child referred by a pediatrician for a heart murmur to managing complex, life-threatening structural defects in newborns. A large portion of their daily practice involves seeing children sent in for common concerns like chest pain, fainting, or an unusual heartbeat picked up during a routine checkup. Most of these evaluations turn out to be benign, but the cardiologist’s job is to rule out anything serious.
The field has grown into several distinct focus areas. Some pediatric cardiologists specialize in advanced heart imaging, others in electrical rhythm disorders, and others in catheter-based procedures that can fix certain defects without open surgery. There are also specialists who focus exclusively on heart failure and transplantation, cardiac intensive care, and the growing population of adults who were born with heart defects and need lifelong follow-up.
Congenital Heart Defects
Congenital heart defects, meaning problems with the heart’s structure that are present at birth, are the primary focus of pediatric cardiology. These range from mild to severe. A small hole between two heart chambers (called a ventricular or atrial septal defect) may cause no symptoms and sometimes closes on its own. On the other end of the spectrum, conditions like hypoplastic left heart syndrome, where the entire left side of the heart is underdeveloped, require multiple surgeries starting in the first days of life.
The CDC lists more than a dozen types of congenital heart defects, and many of them are classified as “critical,” meaning they need intervention in the first year. These include tetralogy of Fallot (a combination of four structural problems that reduces oxygen in the blood), transposition of the great arteries (where the two main blood vessels leaving the heart are switched), and pulmonary atresia (where the valve that controls blood flow to the lungs doesn’t form properly). Each of these requires a different treatment approach, which is part of why the specialty demands such extensive training.
Acquired Heart Conditions in Children
Not all childhood heart problems are present at birth. Kawasaki disease, which causes inflammation of blood vessels and can damage the coronary arteries, is one of the most important acquired heart conditions in children. Acute rheumatic fever, triggered by untreated strep throat, can permanently damage heart valves. Myocarditis, an inflammation of the heart muscle often caused by a viral infection, can weaken the heart’s pumping ability and sometimes leads to a form of heart failure called dilated cardiomyopathy.
These acquired conditions require a different diagnostic and treatment approach than structural defects, but they fall squarely within pediatric cardiology’s scope. Researchers continue to study the role of immune and genetic factors in conditions like myocarditis, particularly the connection between viral infections and long-term heart muscle damage.
How Heart Problems Are Detected
Detection can start before a baby is born. A fetal echocardiogram, essentially an ultrasound focused on the baby’s heart, is typically performed during the second trimester when there’s a reason for concern. Reasons for ordering one include an abnormal-appearing heart on a routine prenatal ultrasound, a family history of congenital heart disease, maternal diabetes, or an irregular fetal heart rhythm. Some centers can perform these as early as 13 to 14 weeks of gestation, though image quality improves later in pregnancy. Success rates for visualizing the heart’s main structures are consistently above 90% at major referral centers.
After birth, the most common diagnostic tools are straightforward. An electrocardiogram (EKG) uses stickers placed on the chest, arms, and legs to measure the heart’s electrical activity, detecting rhythm abnormalities or signs that a heart chamber is enlarged. An echocardiogram, the workhorse of pediatric cardiology, uses ultrasound to create a real-time video of the heart’s interior. A first echocardiogram can take 30 to 60 minutes and can detect most congenital defects and problems with how the heart muscle is functioning.
For children with symptoms that come and go, like occasional racing heartbeats or fainting spells, cardiologists use portable monitors. A Holter monitor records every heartbeat for 24 to 48 hours, while an event monitor can be worn for up to a month. Older children and teens who experience symptoms during physical activity may do exercise stress testing on a treadmill or stationary bike while connected to an EKG. When more detailed images are needed, cardiac MRI provides high-resolution pictures without radiation, and cardiac CT offers fast, detailed views of the heart’s anatomy and surrounding blood vessels.
Catheter-Based and Surgical Treatment
Many heart defects that once required open-heart surgery can now be treated through cardiac catheterization. In this procedure, a thin tube is threaded through a blood vessel in the groin or neck up to the heart, where the cardiologist can measure pressures and oxygen levels in each chamber and, in many cases, perform repairs.
Closing a hole between the upper chambers of the heart (atrial septal defect) through a catheter has become the preferred approach over surgery at many centers when conditions are favorable. The same is true for closing a patent ductus arteriosus, an extra blood vessel that normally closes shortly after birth but sometimes doesn’t. Balloon valvuloplasty, where a small balloon is inflated inside a narrowed heart valve to open it up, has been the standard treatment for pulmonary valve stenosis since the 1980s and works in patients of all ages. More recently, catheter-based pulmonary valve replacement has allowed cardiologists to implant a new valve without open surgery, with good results in hundreds of patients.
For defects that do require surgery, a pediatric cardiac surgeon works closely with the cardiologist to plan the procedure and manage long-term follow-up.
The Care Team
Treating a child with a heart condition is rarely a one-person job. A pediatric heart center brings together cardiologists, cardiac surgeons, anesthesiologists specializing in cardiac cases, and intensive care physicians who manage recovery after surgery. Pediatric cardiac intensive care has emerged as its own distinct discipline, with doctors devoting their entire careers to postoperative care. Specialized nurses play a critical role in outcomes, as do perfusionists (who run the heart-lung machine during surgery) and catheterization lab technologists.
In many programs, postoperative care is delivered jointly by anesthesiologists, cardiologists, and surgeons working as a team rather than one group handing off to another. This collaborative model has become the standard at successful centers.
Training Required
Becoming a pediatric cardiologist takes a minimum of 10 years of training after college: four years of medical school, three years of pediatric residency, and a three-year fellowship in pediatric cardiology. The fellowship includes two years of intensive clinical rotations through echocardiography, cardiac catheterization, inpatient cardiology, and the cardiac ICU, plus a full year dedicated to research. Cardiologists who want to specialize further in areas like electrophysiology or interventional catheterization typically complete additional training beyond that.
How It Differs From Adult Cardiology
Adult cardiology deals primarily with diseases that develop over a lifetime, like coronary artery disease from atherosclerosis, heart attacks, and age-related valve degeneration. Pediatric cardiology is fundamentally different because it centers on hearts that formed abnormally or are affected by childhood-specific diseases. The anatomy can be wildly variable from patient to patient, with some children born with hearts that are structurally unique in ways that don’t fit neatly into categories.
There’s also a growing bridge between the two fields. Children who undergo heart surgery or catheter procedures in infancy now routinely survive into adulthood, creating a population of adults with congenital heart disease who need specialized, lifelong cardiac care. Many pediatric cardiologists now work in adult congenital heart disease clinics to provide continuity for these patients as they age, go through pregnancy, and face new cardiac challenges decades after their original repairs.