Pediatric Heart Surgery | Specialists and Information

Pediatric cardiac surgery encompasses all surgical treatments for congenital heart defects. Just like cardiac surgery, pediatric cardiac surgery is a relatively new field of medicine.

The use of the heart-lung machine has revolutionized pediatric cardiac surgery. This machine takes over the functions of the heart and lungs, not only during open-heart surgery. The heart-lung machine has become an indispensable part of everyday surgical practice in pediatric cardiac surgery.

However, new surgical techniques, improved suture materials, and sterile conditions have also helped further reduce the mortality rate among young patients. In general, doctors today tend to opt for early pediatric cardiac surgery to correct congenital heart defects.

Heart defects are the most common congenital abnormalities in children. In Germany, approximately 5,000–6,000 newborns are affected each year. Although prenatal diagnostics are improving, the number of children with heart defects is not decreasing.

An echocardiogram is used to diagnose congenital or acquired heart defects or heart diseases @ liubovyashkir /AdobeStock

Early diagnosis and optimized birth and treatment plans increase the chances of survival, even in cases of the most severe heart defects. Pediatric cardiac surgery has now become a specialized field within cardiac surgery.

There are several centers for pediatric cardiac surgery in Germany. However, not every hospital offers pediatric cardiac surgery.

Heart defects in the area of the heart’s septum are very common in infants and children. These can be small or large septal defects that lead to mixed blood in the atria or ventricles.

Mixed blood means that, due to the defect, oxygen-poor blood from the body mixes with oxygen-rich blood from the lungs.

Symptoms and Indications for Surgery

Symptoms vary in severity depending on the size of the septal defect. Larger holes result in mixed blood flow and thus a reduced oxygen supply to the body. This manifests itself, for example, in a change in skin color and a lack of stamina.

In such cases, pediatric cardiac surgery can help by surgically closing the defect. Smaller defects, on the other hand, can remain undetected and unnoticed for years. Heart defects can usually be diagnosed via ECG, cardiac catheterization, or other imaging techniques.

The doctor can then discuss the best course of action with the parents. Not every heart defect immediately requires pediatric cardiac surgery.

Many of the smaller septal defects initially only require regular echocardiographic monitoring. In infants and children, many holes in the septum between the right and left sides of the heart close on their own. They do not require surgery.

If a hole persists, it is usually not a problem. Heart defects of this type can be treated without significant risk even during early childhood or adolescence.

However, if treatment is not provided in a timely manner, serious complications may arise, such as:

• Inflammation
• Heart rhythm disorders
• Valvular heart disease or
• permanent changes in the lungs

A common septal defect is the defect in the septum between the right and left ventricles. The surgery follows a standardized protocol and is characterized by a low risk of complications.

In a septal defect, blood flows from the left ventricle into the right ventricle, leading to overload of the left heart and the lungs @ Kadmy /AdobeStock

Procedure for Correcting a Septal Defect

First, doctors open the chest at the sternum. The heart-lung machine simultaneously takes over circulation and replaces the heartbeat and breathing.

For the duration of the surgery, doctors stop the heart and open the right atrium. The surgeon accesses the ventricle through the tricuspid valve located there. He closes the defect with several sutures.

This procedure can also be used to treat and close other, similar types of congenital heart defects. Depending on the location of the defect, pediatric cardiac surgeons must have various approaches available to access the heart.

Alternative approaches include entering through the left side of the heart (pulmonary valve) or directly through the aortic valve into the left ventricle. In rare cases, doctors open the right ventricle via an incision.

After pediatric heart surgery, the child has a very high chance of leading a healthy life with a functioning heart. Nevertheless, the child’s progress is monitored very closely, especially in the early stages.

Severe heart conditions usually have a negative impact on heart function. That is why it is important to correct them surgically as early as possible through pediatric heart surgery.

For correctable heart defects, cardiac surgeons perform “curative surgery” within the first year of life. Depending on the specific heart defect, surgeries can now even be performed within the first three months of life.

Following successful treatment, near-normal physical and psychological development is possible. This also helps prevent long-term complications resulting from the severe heart defect.

If left untreated, however, conditions such as heart failure and cardiac insufficiency may develop. In the worst-case scenario, the only option is an artificial heart, which can remain in the body only for a transitional period.

Finding a suitable donor heart is often a lengthy process and frequently futile. Early correction of heart defects is therefore the better option for the child’s future.

Heart valve surgery is among the most common treatment options in pediatric cardiac surgery. Today, many complex heart defects can be corrected through precise reconstruction. The body’s own tissue is durable and capable of growth.

Especially during childhood and adolescence, the body’s proportions and tissues continue to change significantly. Valve repair is therefore preferable to valve replacement.

Most, if not all, hospitals aim for reconstruction in valve surgery. This has been shown to offer benefits for heart function and quality of life.

In cases of valve replacement, doctors often have to seek and find personalized solutions for young patients. Physical activity, a planned pregnancy, or the need for care due to a physical or mental disability also influence the choice of prosthesis.

Replacement valves made from the patient’s own tissue are most commonly used in pediatric cardiac surgery for pulmonary valve replacement.

Aortic Valve Reconstruction and Aortic Valve Replacement

In addition, doctors often need to perform surgery on the aortic valve. For this procedure as well, they must open the chest along the sternum to expose the heart.

Once the heart has been stopped and the heart-lung machine has taken over, they open the aorta. Through this incision, the aortic valve in the left side of the heart can be accessed and specifically repaired.

In pediatric cardiac surgery, two surgical procedures are used for this purpose:

• In the Ross procedure, doctors repair the aortic valve using tissue from the pulmonary valve
• The David procedure, on the other hand, replaces the aortic root while preserving the aortic valve

Aortic valve reconstruction generally has a good prognosis. Its longevity depends on the complexity and the outcome of the actual repair.

It is most effective when doctors reconstruct the heart valve as a tricuspid valve (like the original).

To prevent blood clots from forming after heart valve surgery, children are given anticoagulants (aspirin, 2 mg/kg) for three months.

If the patient receives a mechanical valve (not made from the patient’s own tissue or donor tissue), the valve has an unlimited lifespan. However, the patient must take anticoagulants for life, as deposits can form on the artificial surfaces of the heart valve replacement.

Over the years, there is then a risk of bleeding or clot formation that should not be underestimated.

If a young patient receives a bioprosthesis, anticoagulation is necessary for only three months provided there is normal ventricular function and sinus rhythm.

However, young patients rapidly degrade these valves, which necessitates replacement and thus another surgery.

Anticoagulation is not required after a Ross procedure. In the medium term, outcomes are also favorable in adulthood.

In the long term, however, aortic valve insufficiency often recurs (autograft).

One option in pediatric cardiac surgery that is currently still in the trial phase is “grow-with-the-child” biovalves. These valves are based on cell-free homografts (human valves). They are currently still being tested. No information on long-term success is available at this time.

However, previous trials using porcine valves as biological replacements have shown a shorter lifespan than homografts or other biovalve systems. The use of such growing biovalves is one of the major visions for the future of pediatric cardiac surgery.

Mitral Valve Surgery and Mitral Valve Replacement in Pediatric Cardiac Surgery

In this procedure as well, the surgeon opens the sternum to expose the heart. The heart-lung machine takes over the functions of the heart and lungs, which are temporarily shut down, to maintain circulation and respiration.

During this procedure, doctors open the left atrium of the heart to treat the mitral valve. In cases of mitral valve stenosis, the surgeon attempts to correct the narrowing by making an incision in or thinning the valve leaflets.

If the mitral valve is too weak (insufficient), the doctor must replace it with a suitable implant or autograft. Mechanical prostheses are also an option for mitral valve replacement in children.

The older a child gets, the more frequently combinations of a previously corrected heart defect and newly acquired defects can occur. For this reason, many children who have undergone surgery must later undergo pediatric heart surgery again. 

Scarring and repeated physical and emotional stress pose a major challenge in modern pediatric cardiac surgery. This steadily growing and largest patient group with congenital heart defects is not homogeneous.

To reduce the burden on children and adolescents, all atrial septal defect surgeries are now performed as minimally invasive procedures. In these procedures, doctors make an incision in the skin on the right side, just below the left breast. They use a catheter to repair the hole in the septum.

In infants and toddlers, doctors also take care to preserve the sternum and open it only halfway.

This surgical approach is particularly suitable for:

• Atrial septal defect
• Ventricular septal defect or
• AV canal repair

If severe heart defects are treated as early as infancy, the children usually develop normally thereafter.

To correct congenital heart defects as early as infancy, doctors need state-of-the-art surgical techniques and a great deal of experience.

Transposition of the great vessels of the heart poses a particular challenge. In this condition, the pulmonary artery (the artery that branches off from the heart to the lungs) and the aorta (the main artery of the body) are “connected” in reverse: In these children, the pulmonary artery connects where the aorta should actually connect. The aorta, however, diverts blood into the lungs.

As a result, hardly any oxygen-rich blood reaches the body. Without pediatric heart surgery, these newborns would die shortly after birth. If left untreated, oxygen exchange occurs in the first few days of life via postnatal shunt openings. These are windows or openings in the heart that close only some time after birth.

Today, doctors correct transposition of the great arteries with a switch operation. During this procedure, they detach the great artery, the aorta, and the pulmonary artery from the heart. They then swap their positions and reattach them to the heart in their normal locations.

Procedure for Arterial Switch Surgery

During this surgery, doctors open the chest along the sternum and expose the heart. Once the heart has stopped beating and the heart-lung machine is maintaining circulation, the surgeon can sever the pulmonary artery and the aorta.

After swapping the vessels, the surgeons immediately reattach them to the heart in their correct positions. They must also check the origins of the coronary arteries to ensure that the heart muscle will later receive adequate blood and oxygen.

This operation is a true milestone in pediatric cardiac surgery, as it makes it possible to treat an otherwise fatal heart defect.

In cases of particularly severe heart defects, corrective surgery involving separate systemic and pulmonary circulations and two heart chambers is impossible. 

In such cases, doctors perform the procedure in several stages to stabilize the patient and improve their quality of life.

First, the doctors ensure blood flow to the body and lungs, usually via mixed blood and later without involving the ventricles.

To do this, they divert the oxygen-poor blood directly from the large systemic veins into the pulmonary artery (Fontan circulation). In this way, they bypass and relieve the heart. They divert the blood from the inferior vena cava past the heart to the pulmonary artery.

The blood no longer flows directly through the heart. This improves blood flow, resulting in fewer arrhythmias and a higher quality of life.