Hypoplastic left heart syndrome

Síndrome de la hipoplàsia de cavitats esquerres a Vall d'Hebron

Hypoplastic left heart syndrome (HLHS) encompasses a series of anomalies that all have a very small, or “hypoplastic”, left ventricle, which is incapable of pumping the required amount of blood to supply all the organs and tissue in the body. In this situation, the right ventricle keeps blood circulating. Children with this type of anomaly tend to have other structures of the left side of the heart that are also smaller. Often the mitral valve, the aortic valve or the aorta itself are smaller than they should be. Hypoplasia of the left chambers is one of the most serious heart defects, although very good outcomes are achieved in centres with experience of the condition such as ours.

Description

Diagnosis

It is often diagnosed in the foetus during an echocardiogram. This test can identify which structures are affected by the syndrome in order to decide the best treatment.

Typical treatment

These anomalies are usually treated with surgery during the first week of the baby’s life. This operation connects all the vessels coming out of the heart into just one, to ensure blood flows to the body. This procedure is known as “the Norwood procedure”.

In this first surgery, blood reaches the lungs via a conduit that exits the aorta (systemic-pulmonary fistula). Two further procedures will be needed. The aim of this surgery is to make the heart work solely with the oxygenated blood it receives from the lungs, and to pump it to the tissues of the body. Blood flows to the lungs through the network of veins that transport unoxygenated blood (Glenn and Fontan procedure).

Children who have had this heart defect must have their neurodevelopment closely monitored by experts in this field, to evaluate the child’s educational development and growth. Close monitoring is necessary from a cardiological point of view, above all during the first few days of a child’s life. Monitoring the patient will show when surgery is necessary, how they should be managed medically, and how to treat complications, should any arise.