Absent pulmonary valve is a rare defect in which the pulmonary valve that carries oxygen-poor blood from the heart to the lungs is either missing or poorly formed. This condition is present at birth (congenital).
See also: Tetralogy of Fallot
Absent pulmonary valve occurs when the pulmonary valve doesnâ€™t form or develop properly while the baby is in the motherâ€™s womb. It often occurs as part of a rare condition called tetralogy of Fallot.
When the pulmonary valve is missing or does not work well, not enough blood can flow to the lungs to get oxygen.
There is also usually a hole between the left and right ventricles of the heart (ventricular septal defect). This defect will also lead to low-oxygen blood being pumped out to the body.
The skin will have a blue appearance (cyanosis), because the body's blood contains a low amount of oxygen.
Absent pulmonary valve also results in very enlarged (dilated) branch pulmonary arteries (the arteries that carry blood to the lungs). They can become so enlarged that they press on the tubes that bring air to the lungs (bronchi) and cause breathing problems.
Other heart defects that can occur with absent pulmonary valve include:
Heart problems that occur with absent pulmonary valve may be due to defects of the genes (chromosomes).
Symptoms can vary depending on which other defects the infant has, but may include:
Absent pulmonary valve may be diagnosed before the baby is born with a test that uses sound waves to create an image of the heart (echocardiogram).
During an examination, the doctor may hear a murmur in the infantâ€™s chest.
Tests for absent pulmonary valve include:
Infants who have breathing symptoms should have surgery as quickly as possible. Even infants without symptoms should have surgery within the first 3-6 months of life.
Depending on the type of heart defects the infant has, surgery may involve:
Types of surgery for absent pulmonary valve include:
Infants with severe breathing symptoms may need to get oxygen or be put on a breathing machine.
Without surgery, most infants who have severe lung complications will die.
Surgery can treat the condition and relieve symptoms in many cases.
Call your health care provider if your infant has symptoms of absent pulmonary valve. If you have a family history of heart defects, talk to your doctor before or during pregnancy.
There is no way to prevent this condition; however, families can have genetic testing to determine their risk of certain related heart defects.
Absent pulmonary valve syndrome; Congenital absence of the pulmonary valve; Pulmonary valve agenesis