Truncus arteriosus

Diagnosis

Truncus arteriosus is often diagnosed shortly after a child’s birth, with affected newborns displaying bluish or grayish skin color and respiratory issues. During the initial medical assessment, healthcare professionals routinely evaluate the baby’s lung function through auscultation of their breath sounds. In cases of truncus arteriosus, healthcare providers may identify abnormal lung sounds suggesting fluid retention. Furthermore, they listen to the baby’s heart to detect irregular heartbeats and the characteristic whooshing sound known as a murmur.

To confirm the diagnosis of truncus arteriosus, several tests are performed:

• Pulse oximetry: This involves placing a sensor on the baby’s fingertip to measure the oxygen levels in the blood. Low oxygen levels may suggest a heart or lung problem.
• Chest X-ray: This diagnostic imaging test provides insights into the condition of the heart and lungs, allowing for an assessment of heart size and the presence of excess fluid in the lungs.
• Echocardiogram: The primary diagnostic tool for truncus arteriosus, an echocardiogram employs sound waves to generate images of the functioning heart. In cases of truncus arteriosus, the test reveals a single, large vessel emerging from the heart and often identifies a hole in the wall that separates the lower heart chambers.

Treatment

Infants born with truncus arteriosus require surgery to improve their blood flow and oxygen levels. Additional procedures or surgeries may be necessary as the child grows, and medications may be prescribed before surgery to support heart health.

Medications

• Water pills (diuretics): Are given to help the kidneys remove excess fluid from the body, which is a common symptom of heart failure.
• Positive inotropes: Are used to strengthen the heart’s pumping ability, improving blood flow and blood pressure control. They may be administered intravenously in cases of severe heart failure.

Surgery and procedures

Most infants with truncus arteriosus undergo surgery within the first few weeks of life, with the specific procedure tailored to the baby’s condition.

The surgeon typically:

• Rebuilds the single large vessel and aorta to create a new, complete aorta.
• Separates the upper part of the pulmonary artery from the single large vessel.
• Uses a patch to close the hole between the two lower heart chambers.
• Places a tube and valve to connect the right lower heart chamber with the upper pulmonary artery, forming a new, complete pulmonary artery.

It’s important to note that the tube used to create the new pulmonary artery does not grow with the child, necessitating follow-up surgeries to replace it as the child grows.

In the future, some of these surgeries may be performed using a flexible catheter instead of open-heart surgery. This involves inserting a catheter into a blood vessel in the groin and guiding it to the heart, where a new valve can be delivered to the appropriate location. This approach can also include balloon angioplasty, where a small balloon is inflated to widen a blocked artery.

After truncus arteriosus surgery, lifelong follow-up care with a congenital cardiologist, a heart doctor specializing in congenital heart diseases, is essential.