What sort of problem is an absent pulmonary valve?

Absent/ never formed: The defect occurs when an unopen artery without a valve cannot carry blood to the lungs. This is ok during pregnancy since fetal lungs don't need to receive blood & add o2.Blood is pumped thru bypass circuits to the body.After birth, when lungs must supply o2, this can be a fatal defect.If recognized early, drs can keep the bypass open & heart surgeons can reroute the flow with open heart surgery.

Rare CHD: A rare congenital heart defect. The pulmonary valve doesn’t form and not enough blood can flow to the lungs to get oxygen; only through the PDA (patent ductus arteriosus). It often occurs as part of a condition called tetralogy of fallot. There is usually a hole between the left and right ventricles of the heart (ventricular septal defect). Surgery as a newborn is required.