Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome


The main pumping chamber (the left ventricle) is very small and the aortic and mitral valves are either very narrow, thickened, or entirely blocked.

The babies are in major difficulties in the first few days of life as changes in the circulation occur with closure of the duct. This is one of the most serious of all heart abnormalities and remains a very difficult area despite the advances that have been made in general over the years.

Early open heart surgery is often recommended. This involves joining the ‘I small aorta to the start of the large lung artery” and dividing this from the branches of the lung artery which are then connected with a shunt from the innominate artery. Arch obstruction (co-arctation) is patched and in addition, the hole between the receiving chambers is enlarged.

This remains a very big operation and leaves the right ventricle pumping blood to the body and also to the lungs via the shunt. This is called a Norwood Stage I operation.

Norwood Stage I

Norwood stage 1

Later, following a catheter test, the upper body vein (the superior vena cava) is joined to the right lung artery. This is called a Norwood Stage II operation – or a Glenn shunt.

Norwood Stage II

Later again, at perhaps 2-4 years of age depending on clinical progress and after a further catheter test, the lower body vein is joined to the lung artery with a further operation known as Norwood Stage III. This produces Fontan-type circulation (total cavo-pulmonary connection).

norwood stage 2

Norwood Stage III

The children require close follow-up, and feeding difficulties are very common in the first months of life. Some children, because of problems with lung arteries or heart muscle function, may be considered for heart transplantation in due course. This congenital heart disorder remains a very difficult area and there is a need for a very wide discussion with the family in the early days. Long-term follow-up and antibiotic prophylaxis is required.

norwood stage 3

Victoria & Tasmania