What is heterotaxy?

  • A rare condition where many organs in the body can be formed abnormally, in the wrong position, or even missing
  • The term heterotaxy is from the Greek words “heteros” meaning “other than” and “taxis” meaning “arrangement”
  • Heterotaxy syndrome is estimated to impact 1 in 10,000 people worldwide and accounts for approximately 3% of all congenital heart defects
  • Many children with heterotaxy have complex heart defects, which are often the most challenging problems associated with heterotaxy
  • In addition to the heart, the intestines, liver, spleen and lungs can also be affected
  • Some children have a mild form of heterotaxy with only minor abnormalities of just one or two organs
  • Other children have very complex forms of heterotaxy involving multiple different organs
  • The causes of heterotaxy are not completely understood, but doctors are working every day to better understand this complex problem

Common problems involved in heterotaxy

  • Complex heart defects, often a combination of the following:
    • abnormal heart position, such as dextrocardia (right-sided heart) or mesocardia (heart in the middle of the chest)
    • holes in the walls that divide the right and left sides of the heart, including atrial septal defects, ventricular septal defect and atrioventricular canal defect
    • abnormal blood vessel positions, such as transposition of the great arteries (TGA)
    • blockage of blood flow to the lungs (pulmonary valve stenosis) or to the body (aortic valve stenosis or coarctation of the aorta)
    • underdeveloped pumping chambers (single ventricle defects)
    • abnormally connected veins (interrupted inferior vena cava or total anomalous pulmonary venous return)
  • Heart rhythm problems:
    • slow heart rhythm (heart block)
    • fast heart rhythm (supraventricular tachycardia)
    • abnormal heart rhythm pathways (dual atrioventricular nodes)
  • Lungs problems:
    • structural problems in the lungs
    • abnormal cilia (ciliary dyskinesia), causing difficulty clearing mucous from the lungs
  • Immune problems:
    • having no spleen (asplenia) or many small spleens (polysplenia) that may nor work properly
    • increased risk of infection
  • Stomach and intestinal problems:
    • abnormal twisting of the intestines (malrotation or nonrotation)
    • a liver that is in the wrong location
    • bile system abnormalities (biliary atresia)
    • abnormal liver blood flow (Abernathy syndrome)

Source: https://www.childrenshospital.org/conditions-and-treatments/conditions/h/heterotaxy