Payday Loans Gauranteed Lowest Fees Payday Loans Gauranteed Lowest Fees

What is Heterotaxy?

Heterotaxy syndrome is a rare birth defect that involves the heart and other organs. The beginning of the word (hetero-) means “different” and the end (–taxy) means “arrangement.”  There are different forms of heterotaxy. All usually involve heart defects, of varying type and severity.  In heterotaxy syndrome, paired organs, such as the lungs or kidneys, are often mirror images of one another instead of having the unique characteristics of right and left that are normally present.

The human body can be viewed as having a right side and a left side. Normally, inside the human body, the right side and the left side are different with respect to the presence of certain organs. Several organs inside the body are placed asymmetrically, meaning that one organ may be located on one side of the body, but not the other. Furthermore, there are some organs that are found on both sides of the body, but have differences that distinguish the right organ from its partner on the left side.T

he normal position of the organs is known as situs solitus; situs inversus is a condition in which the usual positions of the organs are reversed from left to right as a mirror image of the normal condition. If these are the two extreme positions on a continuum of asymmetric thoracic and abdominal organ formation, situs ambiguous covers everything in between.

Classically, it comprises:

More rarely, vascular abnormalities are found, including interrupted inferior vena cava, bilateral superior or inferior venae cavae, intrahepatic interruption of the inferior vena cava with connection to the azygos or hemiazygos veins, and aberrant portal veins.

 Right Atrial Isomerism & Left Atrial Isomerism

What do the terms “right atrial isomerism” and “left atrial isomerism” mean? The heart has tiny pouches, one on each of the two upper chambers, called atrial appendages. In a normal heart, the left atrial appendage looks different than the right. In heterotaxy, the two appendages look similar. “Isomerism” means mirror images. Hence the terms “right atrial isomerism” and “left atrial isomerism.”

  

The term Isomerism actually comes from a chemistry principal of isomers (Isomers are molecules that have the same molecular formula, but have a different arrangement of the atoms in space.) Optical Isomerism is when two groups of molecules (isomers) have a mirror image of each other.  

 But this isn’t completely accurate analogy for the definition of  Isomerism relating to heart defects because Right Isomerism is associated with having asplenia (or lack of spleen) so it isn’t quite accuarte to say that all the organs are there but just in the wrong place.  It isn’t even accuarte to assume this literal translation is accurate because it is now known that many organs are developed abnormally during embroyonic development with Heterotaxy. 

There have been many attemps at trying to classify Heterotaxy into types.  Asplenia vs. Polysplenia, right isomerism vs. left isomerism. the outlet of arteries, ect…  The problem with these classifications is that their are always the babies that don’t fit into one of these groups, and Heterotaxy has such a wide range of congenital anomalies with varying groups of defects.  Having said that, I will just for clarification give a generalized overview of these categories of Heterotaxy because their are many children that fit nicely into these subtypes.

Right Isomerism/Asplenia -

  • ‘Single Ventricle’ physiology (in quotes because many times there does exist a very primitive form of the left ventricle but it is usually not functional)
  • Common Atrium
  • Double Outlet Right Ventricle (the two great arteries come out of the right ventricle only- which would make sense, when for all-intents-and- purposes, the left ventricle doesn’t exist)
  • Situs inversus or situs ambiguus (reffering to organ arrangement)
  • Asplenis (lack of spleen)
  • APVR – Anomolous pulmonary venous return (which just refers to the abnormal arrangement of the pulmonary veins; these can have partial abnormal arrangement (PAPVR) or total abnormal arrangement (TAPVR))
  • CAVC - Common Atrioventricular Canal (meaning there is just one working heart valve simply called the ‘common’ valve as oppose to the healthy heart which has two valves the tricuspid and  mitral valves. )
  • Midline liver (this just means that the liver runs down the middle of the body instead of off to one side.)
  • Malrotated intestines (intestines aren’t arranged properly) 

 

Left Isomerism/Polysplenia-

  • ‘Single Ventricle’ physiology (in quotes because many times there does exist a very primitive form of the right ventricle but it is usually not functional)
  • Common Atrium
  • Double Outlet Left Ventricle (the two great arteries come out of the left ventricle only- which would make sense, when for all-intents-and- purposes, the right ventricle doesn’t exist)
  • Situs inversus or situs ambiguus (reffering to organ arrangement)
  • Polysplenia (usually Left Isomerism is associated with either a very small spleen or very small mulitple spleens that usually don’t function as well as one healthy spleen)
  • APVR – Anomolous pulmonary venous return (which just refers to the abnormal arrangement of the pulmonary veins; these can have partial abnormal arrangement (PAPVR) or total abnormal arrangement (TAPVR))
 

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

Set your Twitter account name in your settings to use the TwitterBar Section.