These are heart defects that are present at birth and are due to the heart not developing properly while the baby is in the womb. Many of these heart problems are picked up on ultrasound scans during pregnancy but sometimes they are discovered after birth, and in other cases not until adulthood.

In many cases, no obvious cause is identified but there are a number of factors that are known to increase the risk of congenital heart disease. For example, if the mother is infected with rubella, takes certain medicines or has diabetes during pregnancy, the risk that the baby will be born with a heart defect is higher. Also, a number of genetic conditions may cause congenital heart disease, such as Down’s syndrome.


There are many types of congenital heart disease with many different variations, and sometimes several defects can occur together. Some of the more common types include: –

  • ventricular or atrial septal defects (VSD or ASD) – there is a hole in the wall that separates the chambers of the heart
  • patent ductus arteriosus (PDA) – there is a connection between the main arteries of the heart that should have closed after birth
  • Abnormalities of the heart valves – valves may be abnormally shaped or narrowed, or in some cases absent
  • coarctation of the aorta – this is a narrowing of the main blood vessel which carries blood from the heart to the body
  • tetralogy of Fallot – this is a rare combination of four heart defects together
  • transposition of the great arteries – there is an abnormal arrangement of the main blood vessels that leave the heart
  • hypoplastic left heart syndrome – the left side of the heart is small and underdeveloped


Treatment depends on the type of congenital heart disease and the severity. In some cases, the defect is minor and no treatment is needed, whilst other cases may be very serious and complex, and require urgent surgery. Sometimes, several operations may be needed to correct the defect.

Relevant Research

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Through pioneering research and accessible education, Heart Research UK aims to reduce the number of people developing and dying from heart disease, while improving and extending the lives of those affected.

As a charity, we can only do this with your help.

People with certain types of heart disease have a higher risk of developing serious complications from Covid-19 and there is evidence that the virus can cause damage to the heart.

We must continue to do all we can to prevent and treat heart disease.

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