Right and left isomerism: the cardiac surgeon's view.

We have treated by palliative or corrective surgery 12 patients with the complex cardiovascular anomalies associated with right isomerism (asplenia syndrome) or left isomerism (polysplenia syndrome). A systemic-pulmonary artery shunt was performed in 4 patients, with 2 early deaths. Anatomical intracardiac repair was successfully done in 2 patients, while an orthoterminal repair using a modified Fontan procedure was attempted in 5 patients, only 1 of whom survived. A 1-year-old girl with diffuse pulmonary arteriovenous fistulas associated with left isomerism was not considered a good candidate for operation after an exploratory sternotomy. The surgical options and technical problems related to the complex intracardiac morphology of these developmental syndromes are presented.