Single ventricle anomalies refer to a category of rare heart conditions that can develop in the growing fetus. In a normal heart, the two ventricles work by collecting blood and pumping it to the lungs or the rest of the body. With this condition, one of the ventricles does not develop properly. The defect can be mild to severe. Other heart problems may be present, as well.

Examples of single ventricle anomalies include:

  • Tricuspid atresia—tricuspid valve does not develop
  • Pulmonary atresia—pulmonary valve does not develop
  • Hypoplastic left heart syndrome—left side of the heart does not develop properly
  • Double inlet left ventricle—large left ventricle and small right ventricle

Heart Chambers and Valves
heart anatomy
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These anomalies are congenital defects. This means that the baby is born with the condition. The abnormality develops while the baby is forming in the womb. It is not known exactly why the heart develops this way in some babies.