Truncus arteriosus

  • Definition
    • Truncus arteriosus is a rare type of heart disease that in which a single blood vessel (truncus arteriosus) comes out of the right and left ventricles, instead of the normal 2 vessels (pulmonary artery and aorta). It is present at birth (congenital heart disease).

      There are different types of truncus arteriosus.

  • Alternative Names
    • Truncus

  • Causes
    • In normal circulation, the pulmonary artery comes out of the right ventricle and the aorta comes out of the left ventricle, which are separate from each other.

      With truncus arteriosus, a single artery comes out of the ventricles. There is most often also a large hole between the 2 ventricles (ventricular septal defect). As a result, the blue (without oxygen) and red (oxygen-rich) blood mix.

      Some of this mixed blood goes to the lungs, and some goes to the rest goes of the body. Often, more blood than usual ends up going to the lungs.

      If this condition is not treated, 2 problems occur:

      • Too much blood circulation in the lungs may cause extra fluid to build up in and around them. This makes it hard to breathe.
      • If left untreated and more than normal blood flows to the lungs for a long time, the blood vessels to the lungs become permanently damaged. Over time, it becomes very hard for the heart to force blood to them. This is called pulmonary hypertension, which can be life threatening.
  • Symptoms
    • Symptoms include:

      • Bluish skin (cyanosis)
      • Delayed growth or growth failure
      • Fatigue
      • Lethargy
      • Poor feeding
      • Rapid breathing (tachypnea)
      • Shortness of breath (dyspnea)
      • Widening of the finger tips (clubbing)
  • Exams and Tests
  • Treatment
    • Surgery is needed to treat this condition. The surgery creates 2 separate arteries.

      In most cases, the truncal vessel is kept as the new aorta. A new pulmonary artery is created using tissue from another source or using a man-made tube. The branch pulmonary arteries are sewn to this new artery. The hole between the ventricles is closed.

  • Outlook (Prognosis)
    • Complete repair most often provides good results. Another procedure may be needed as the child grows, because the rebuilt pulmonary artery that uses tissue from another source will not grow with the child.

      Untreated cases of truncus arteriosus result in death, often during the first year of life.

  • Possible Complications
    • Complications may include:

      • Heart failure
      • High blood pressure in the lungs (pulmonary hypertension)
  • When to Contact a Medical Professional
    • Call your health care provider if your infant or child:

      • Appears lethargic
      • Appears overly tired or mildly short of breath
      • Does not eat well
      • Does not seem to be growing or developing normally

      If the skin, lips, or nail beds look blue or if the child seems to be very short of breath, take the child to the emergency room or have the child examined promptly.

  • Prevention
    • There is no known prevention. Early treatment can often prevent serious complications.

  • References
    • Fraser CD, Carberry KE. Congenital heart disease. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 59.

      Webb GD, Smallhorn JF, Therrien J, Redington AN. Congenital heart disease. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 62.