Obstruction Defects ( Atresia/ Coarcation/ Stenosis)
Sometimes one of the hearts valves is narrowed, blocked or missing, or the main artery to the body (aorta) is narrow. These conditions may be found in association with other defects and the problems caused will depend on where and how severe the blockage is and what the other defects are.- Atresia - blocked, missing or never formed
- Coarctation - narrowing of the aorta
- Stenosis - narrowing of a valve or blood vessel
Aortic Atresia
With this condition the valve between the left ventricle (pumping chamber) and the aorta (main artery to the body) is blocked or missing and therefore blood cannot pump from the ventricle to the body, so the route the blood takes is through the ductus arteriosus (which bypasses the baby’s lungs in the womb). Depending on the other defects found, treatment may include giving drugs to keep the ductus arteriosus from closing (as it normally does shortly after birth). The baby will require an operation to re-route the blood flow, so that the right ventricle can pump the blood to the body.Aortic Stenosis
Here the aortic valve between the left ventricle (pumping chamber) and the aorta (main artery to the body) does not open properly. This means that the heart has to work harder than normal to pump the blood through the valve and around the body.Treatment may be by balloon dilation by catheter to widen the valve, or if this is unsuccessful or not possible, valve surgery will be required.
Coarctation of the Aorta
This is a narrowing of the aorta (main artery) from the heart to the body. This usually is diagnosed during pregnancy or soon after birth, when the baby becomes ill. The doctors will resuscitate the baby and start a drip with prostaglandin. This will reopen the ductus arteriosus (which bypasses the baby’s lungs in the womb) and allow the baby to recover. An operation will then be required to widen out the narrowed area of aorta.Rarely, coarctation may be diagnosed in later childhood, and it may then be possible to treat it with a balloon and stent (open tube used to keep the artery open) inserted from the groin.
Mitral Atresia
This is an uncommon condition, where the left sided heart valve (mitral) has not formed. The blood is unable to enter the left ventricle and to be pumped round the body properly. It usually mixes with the blue blood from the body.The diagnosis will be made as a result of too little blood going to the lungs (Blue baby) or too much (breathless baby) or both. The treatment will depend on the associated conditions.
