Definition

Truncus arteriosus is a very rare heart defect. The heart has four chambers: two atria and two ventricles. In a normal heart, blood travels from the right ventricle through the pulmonary artery to the lungs. After oxygenated blood comes back to the heart, blood is pumped out of the left ventricle through the aorta to the rest of the body.

With truncus arteriosus, one large vessel forms, instead of the pulmonary artery and the aorta. Also, in the two ventricles of the heart, part of the wall that divides the chambers is missing. Because of these defects, oxygen-rich blood is not circulated normally through the body.

Heart Chambers and Valves

heart anatomy

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Blood Flow Through the Heart

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Causes

Truncus arteriosus is a congenital defect. This means that the heart forms incorrectly while the baby is in the womb. It is not known exactly why some babies’ hearts develop this way.

Risk Factors

Some risk factors for congenital heart disease may include:

    
  • Chromosomal disorders (eg, Down syndrome , DiGeorge syndrome )
  • Conditions during pregnancy, such as:     
  • Being infected with a virus (eg, rubella )
  • Having poorly controlled diabetes
  • Drinking alcohol
  • Taking certain medicines (eg, thalidomide )

    • Symptoms

    Symptoms may include:

        
  • Blue or pale grayish skin color
  • Fast breathing
  • High blood pressure
  • Irritability
  • Poor feeding/poor weight gain

    • The doctor may also detect a fast heart rate during the exam.

    This condition can lead to heart failure . If your child has any of these symptoms, get medical care right away.

    Diagnosis

    Your doctor will ask about your child’s symptoms and medical history. A physical exam will be done. Tests may include:

        
  • Blood tests, blood pressure tests, and oxygen saturation tests
  • Echocardiogram —an imaging test that uses sound waves to look at the size, shape, and motion of the heart
  • Chest x-ray —an imaging test that uses low amounts of radiation to create an image of the chest
  • Electrocardiogram —a test that measures the electrical activity of the heart

    • Treatment

    Talk with the doctor about the best treatment plan for your child. Treatment options include:

    Surgery

    Surgery is usually done right away, during infancy. The type of surgery depends on how severe the defect is. The goals are to improve circulation, which may be done by:

        
  • Creating a new pulmonary artery to carry blood to the lungs
  • Creating a new aorta to carry blood to the rest of the body
  • Closing the hole in the wall between the lower chambers of the heart

    • Other surgeries may be needed as your child grows.

    Medication

    Before surgery, you child may need to take:

        
  • Diuretics—to decrease fluid retention
  • Digoxin (Lanoxin)—to improve heart function

    • After surgery, your child may need antibiotics prior to some medical or dental procedures. This is to prevent an infection in the heart.

    Lifelong Monitoring

    Your child will have regular exams from a heart specialist.

    Prevention

    Preventing fetal heart defects may not always be possible, but you can reduce your risk by:

        
  • Practicing good prenatal care:     
  • Visit the doctor regularly to monitor your health and the health of the baby. (Prenatal tests may detect a heart defect in a growing fetus.)
  • Make sure you:     
  • Have a healthy lifestyle
  • Eat nutritious food and take prenatal vitamins
  • Do not drink alcohol, smoke , or use drugs during pregnancy
  • Practicing good hygiene and staying away from people who are sick