ABSTRACT
Congenital heart anomalies used to be classified as either “cyanotic” or “acyanotic.” This can be confusing in that some cyanotic conditions are associated with increased pulmonary blood flow such as transposition or total anomalous pulmonary venous connection. Furthermore, this classification system is of little practical importance. A much more helpful classification separates anomalies suitable for biventricular repair from those that will be managed by the single-ventricle track. Many different anomalies are managed along the single-ventricle track leading to the Fontan procedure. The commonest singleventricle anomaly is hypoplastic left heart syndrome. Among the most challenging patients who will be managed with the single-ventricle track are those with heterotaxy.
