Fontan Surgery - Specialists and Information

The Fontan procedure is a type of palliative surgery performed on children with congenital heart defects. It cannot cure the congenital heart defect, but it can improve the patient’s condition.

In the Fontan procedure, doctors reroute blood vessels so that arterial and venous blood flow sequentially through the heart.

Several different variations have evolved from the original Fontan procedure. They are usually performed in two stages, relieve the strain on the heart, and optimize blood flow.

Fontan surgery is performed on patients with a congenital heart defect in whom only one ventricle is functional. This single ventricle must supply both the systemic circulation and the pulmonary circulation. As a result, blood from both circulatory systems mixes. This significantly impairs and strains the heart and lungs.

During the Fontan procedure, the circulatory systems are separated from one another. The systemic venous blood from the systemic circulation flows directly into the lungs without passing through the heart. There, it is oxygenated. The blood from the pulmonary veins enters the atrium and from there into the ventricle. The oxygen-rich blood is then pumped into the systemic circulation. The goal of the surgery is to ensure a near-normal blood supply to the body despite having only one ventricle.

The Fontan procedure has only been available since the 1980s @ Pebo /AdobeStock

The Fontan procedure is performed in several steps:

1. The first step is to ensure the unobstructed flow of blood into and out of the heart. The Norwood procedure, the Damus-Kaye-Stansel procedure, or the Gießen hybrid procedure may be used for this purpose.

2. In the second step, doctors connect the superior vena cava directly to the pulmonary arteries. As a result, blood from the upper half of the body no longer passes through the right side of the heart. Doctors often use the Glenn anastomosis here if a Fontan completion via an extracardiac tunnel is planned. The result of this step is to effectively relieve the burden on the heart. The blood continues to mix. The volume in the heart decreases to a normal level.

3. The third step involves complete circulatory separation. The procedure takes place when the child is between two and three years old.

During this procedure, doctors also separate the inferior vena cava from the right ventricle and connect it to the pulmonary artery. In this way, they reroute and improve blood flow to the lower half of the body. The load on the lungs increases, and cardiac output decreases.

In cases of right-sided heart failure, doctors make use of the remaining function. To do this, they create a surgical connection between the right atrium and the right ventricle. This procedure achieves a better distribution of the workload and can increase cardiac output. Experts also refer to this method as the ¾ heart or Fontan-Björk procedure.

The procedure described above outlines the sequence of the various surgical interventions. However, there are additional techniques for each step that offer the best chances of success for the patient.

Doctors decide which procedure is suitable for the patient after a thorough examination and by taking all factors into account.

The Fontan procedure is suitable for patients who have only one functionally effective ventricle @ alisaaa /AdobeStock

Trained and experienced cardiac surgeons perform the Fontan procedure. Based on the patient’s initial condition, they determine which variant is best suited to achieve the greatest success.

After the surgery, the patient is transferred to the intensive care unit, where medical staff closely monitor and care for them.

The primary goal is to wean the patient off mechanical ventilation so that the lungs can function as respiratory organs, thereby stabilizing circulation. In some children, this can happen as early as in the operating room, while for others it takes longer.

A drainage tube helps remove wound fluid and secretions. Nutrition can be provided intravenously or via a nasogastric tube.

If the Fontan circulation is stable and no complications arise, the child is discharged within a few weeks.

Since the patient has been in the hospital for an extended period, initial difficulties in daily life are to be expected. A consistent daily routine and regular follow-up visits are crucial. During these follow-up visits, doctors check the function of the heart and lungs as well as the healing of the surgical scar.

Patients may only engage in strenuous physical activity or exertion after receiving approval from their pediatrician or cardiac surgeon. Key factors here include postoperative progress, overall healing, and oxygen saturation.

Special caution and regular checkups are necessary on an ongoing basis. Growth, puberty, and, if applicable, comorbid conditions can continually present new challenges and changes.

Since the Fontan procedure is a relatively new technique, its long-term effects cannot yet be fully assessed. Nevertheless, the Fontan procedure is a valuable treatment option. It improves both the patient’s quality of life and life expectancy.

Possible treatment risks and complications during and after Fontan surgery include:

• Protein-losing enteropathy
• Effusions
• Arrhythmias
• Cyanosis

The following tests are therefore important for early detection and treatment of potential problems.

Studies show that patients have an increased risk of liver damage. The short- and medium-term prognosis is favorable. However, there is still insufficient information available regarding the long-term outlook.