HLHS Treatment

The final operation is called the 'Fontan Operation'. It is carried out at three to four years (or later). The aim of the operation is to separate the deoxygenated (blue) blood from the oxygenated (red) blood. The Fontan leads to blue blood (low in oxygen) being channelled through the lungs, without any 'pump' driving it. The right ventricle then pumps the red blood (high in oxygen), round the body. This operation makes the child 'Pink' - but does not correct the original problem.

Not all affected children need to have a Fontan operation. If they are well, with less drastic surgery, they may not have this 'Final' operation. Some children may be unsuitable for a Fontan operation and alternative forms of treatment may be offered
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The Fontan operation has undergone an evolution since its introduction in the late 1960’s, there are two modifications of the original operation that are the most widely used today. In both methods a total cavopulmonary connection is created, but by different means. These modified operations are the:

• Extracardiac conduit Fontan (Diagram above)

  In the extracardiac conduit type of Fontan, one end of a synthetic tube graft is connected to the inferior vena cava and the other end to the pulmonary artery confluence. This pathway has size limitations since the graft cannot grow. Therefore, extracardiac Fontan operation is performed in older children in order to implant a conduit size that will be suitable into adult life.

• Lateral atrial tunnel Fontan

  With the lateral tunnel a baffle is placed in the right atrium to partition systemic from pulmonary venous blood. Because this partition comprises less than half the circumference of the pathway from inferior vena cava to pulmonary artery, the remaining native atrial tissue can grow to accommodate increased systemic venous return over time. The growth potential makes this type of Fontan operation suitable for smaller children without the need for future enlargement of the pathway.