Q20.5: Discordant atrioventricular connection

The upper chambers (ventricles) in your heart are switched in position. This condition is congenital, which means you were born with it.

The heart pumps blood through the body. Inside the heart are 4 chambers. There are 2 heart atria and 2 ventricles. Both heart atria and both ventricles are separated from each other by a partition. Major, important blood vessels branch out of the heart. The main artery (aorta), originating from the left lower chamber (ventricle) of the heart, supplies the whole body with oxygen-rich blood. The right ventricle pumps oxygen-poor blood through the pulmonary artery to the lungs, where the blood is then enriched with oxygen.

Your heart did not develop properly before you were born. This means that your right upper chamber (atrium) is connected to the left lower chamber (ventricle). The left atrium is connected to the right ventricle. These ventricles that have swapped places pump blood through the body and the lungs in the normal way. However, the right ventricle doesn’t normally need very much force to pump blood into the lungs. In your case, the right ventricle has to pump blood into the body with much more force than normal. This puts a lot of strain on your right ventricle.

This heart defect can lead to various symptoms. One may be short of breath, and feel weak or tired. This may affect normal growth. The symptoms may begin shortly after birth.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


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