What Is Truncus Arteriosus

Truncus Arteriosus is a birth defect that affects a baby’s heart. This condition is also known as “common truncus,” or “persistent truncus arteriosus”. Usually, the blood vessel pumping blood out of the heart divides completely into two separate vessels. These vessels are called the pulmonary valve and the aortic valve. Together, both valves regulate a healthy mix of oxygen and blood to the lungs. When the vessel does not divide completely, the heart pumps too much blood into the lungs, causing complications with both the lungs and the heart.

The defect is present at birth and requires immediate treatment. Treatment might involve a combination of medicine, nutrition, and surgery. Truncus arteriosus may result in complications that last into adulthood.

Truncus Arteriosus Types

There are several different truncus arteriosus types. The main difference between the types is the positioning of the pulmonary arteries.

There are three types:

• Truncus arteriosus Type 1—The arteries extend above the valve.
• Truncus arteriosus Type 2—The arteries split but remain close together.
• Truncus arteriosus Type 3—The arteries split and spread farther apart.

Signs & Symptoms

The signs and symptoms of truncus arteriosus generally show within the first few days after the baby is born.

Common truncus arteriosus symptoms:

• Fast breathing
• Extreme sleepiness
• Bluish skin
• Excessive sweating
• Fluttering or pounding heart
• Trouble breathing
• Slow growth
• Uninterested in eating

Please check with your doctor if your baby experiences the following symptoms:

• Extreme sleepiness
• Bluish skin
• Uninterested in eating

There are also several symptoms that require immediate medical care.

If your baby experiences any of the following symptoms, please seek medical attention right away:

• Trouble breathing
• Loss of consciousness
• Worsening bluish skin

Causes

Truncus arteriosus is a rare congenital heart defect. There is no consensus in the medical community on definitive truncus arteriosus causes. However, there are known risk factors for the condition. These risk factors increase the likelihood of a baby being born with the heart defect.

Risk factors include:

• Smoking while pregnant—Smoking during pregnancy increases the risk of delivering a baby with truncus arteriosus.
• Obesity—Pregnant women who meet the medical definition of obese are at higher risk of giving birth to a baby with heart defects.
• Mismanaged Diabetes while pregnant—Untreated or insufficiently treated Diabetes can increase the risk of your baby being born with birth defects.
• Specific medications while pregnant—Doctors often ask pregnant women to avoid many medications during pregnancy because of risks to the baby.
• Consuming alcohol while pregnant—Drinking alcohol during the first trimester of a pregnancy increases the risk of a baby developing truncus arteriosus.
• Chromosomal disorders—Certain disorders caused by extra chromosomes place your baby at higher risk of truncus arteriosus. Two such conditions include DiGeorge’s syndrome and velocardiofacial syndrome.
• Viral illness while pregnant—Developing any viral illnesses during pregnancy increases the risk of your baby experiencing truncus arteriosus.

Diagnosis

Doctors generally complete a truncus arteriosus diagnosis within the first few days after delivery, often before the mother leaves the hospital. Doctors most commonly make a diagnosis after detecting a heart murmur or bluish skin.

Medical personnel use various tests to diagnose truncus arteriosus:

• Chest X-Ray—An X-ray captures images of your baby’s heart to identify potential defects.
• Cardiac Magnetic Resonance Imaging (MRI)—A test that takes detailed, three-dimensional images. The MRI shows abnormalities or defects in your baby’s heart.
• Echocardiogram—A test that uses sound waves to generate images of your baby’s heart.
• Electrocardiogram (ECG)—A test that examines the electrical activity of your baby’s heart.
• Pulse oximetry—Doctors monitor the levels of oxygen in your baby’s blood.
• Cardiac catheterization—Doctors insert a thin tube through a vein or artery. They then navigate the tube to the baby’s heart.

Treatment & Recovery

Truncus arteriosus treatment often involves medication, nutrition, and surgery. Ongoing checkups with a physician after treatment can help prevent further health complications as the baby develops.

Medication

Your doctor may prescribe medicine for your baby that helps reduce their blood pressure, reinforce their heart, and release excess fluid. Not all babies require medicine for truncus arteriosus.

Nutrition

Babies with truncus arteriosus often feel extremely sleepy and uninterested in feeding. Therefore, they do not always get the nutrition their body needs. Your doctor may prescribe formula with a high calorie content to ensure healthy weight gain. If needed, a feeding tube might be used.

Surgery

Your baby may need a series of surgeries to properly repair their heart defect. Doctors might refer to the surgery as a truncus arteriosus repair or a truncus arteriosus repair procedure. The exact nature of the surgery depends on the specific characteristics of the condition. Surgery is typically performed in the first few months after a baby is born.

The surgery might include:

• Repairing a gap between the lower heart chambers.
• Constructing a new aorta to release oxygenated blood to the body.
• Connecting an artificial tube and valve to specific arteries that ensure enough low-oxygen blood reaches the lungs.

Most individuals born with truncus arteriosus need ongoing regular visits with a heart specialist to ensure proper healthy functioning and to prevent future complications.

Living with Truncus Arteriosus

Many patients have questions about living with truncus arteriosus. Effectively treating the condition long-term means understanding how to monitor symptoms, avoid risk, and prevent complications.

Will my child need more surgery in the future?

Individuals with truncus arteriosus may need additional surgery. Artificial valves and arteries might wear down. Your child may also outgrow the artificial devices. In some cases, doctors perform surgery to expand narrowed arteries.

What kind of ongoing care will my child need?

Your child will likely require ongoing checkups with a heart specialist, called a cardiologist. The doctor will monitor heart function. Based on imaging tests such as X-rays and electrocardiograms, they will treat your child’s condition. This treatment may involve additional surgeries or medication.

Will my child have any activity restrictions?

The severity of the condition determines activity restrictions. For mild cases, your child may be able to participate in certain sports. However, intense sports can place your child at risk for health issues. Please speak to your doctor about the most appropriate and safest sports for your child.

How do I prevent endocarditis?

Endocarditis is a bacterial infection that can negatively affect the heart. Your doctor can prescribe medications to help prevent endocarditis. Typically, a patient takes these medications prior to certain dental procedures.

Complications

If truncus arteriosus is left untreated, serious complications can occur.

Common truncus arteriosus complications:

• Heart failure—Heart failure is when the heart is unable to provide the body with enough blood to properly function.
• Breathing problems—Excess blood flow in your baby’s lungs can make it difficult for your baby to breathe.
• Heart enlargement— Also known as cardiomegaly, increased blood flow makes your baby’s heart enlarge and weaken over time.
• High blood pressure in the lungs—Also known as pulmonary hypertension, increased blood in the lungs causes a narrowing of blood vessels. This results in less blood reaching the lungs.

Additional complications can sometimes occur later in life:

• Arrhythmias—Abnormal heart rhythm.
• Progressive pulmonary hypertension—A blood flow obstruction between your heart and lungs.
• Regurgitation—Essentially, regurgitation means leaky heart valves.
• Problems from prior operations—Previous surgeries can sometimes cause issues that require attention, such as replacing artificial devices.

If you or a loved one experience any of these complications, a cardiologist at Baptist Health may be able to help.