You are posted in the Neonatal intensive care unit of the hospital. You get an emergency page that a pregnant patient has just delivered in the Emergency Department, and the child has a congenital cardiac condition for which he will need a Fontan procedure. The Fontan surgery, which involves the anastomosis of the right atrium to the pulmonary artery, is a useful surgical treatment for each of the following congenital cardiac defects EXCEPT:a. Tricuspid atresia
Correct Answer: D
Truncus arteriosus occurs when there is presence of a single arterial trunk, overriding both ventricles (which are connected via a ventricular septal defect). This trunk gives rise to both the aorta and pulmonary artery. Surgical treatment of this defect includes banding of the left and right pulmonary arteries and enclosure of the associated VSD, and hence the Fontan would not be employed in this situation.
The Fontan procedure (usually modified Fontan) refers to the anastomosis of the right atrial appendage (or the superior and inferior vena cava) to the pulmonary artery. Because this procedure leads to an increase in pulmonary blood flow, it as the treatment of choice for treatment of congenital cardiac defects, which decrease the pulmonary artery blood flow (eg, pulmonary atresia and stenosis [C and E] and tricuspid atresia[A]). The Fontan procedure is also used to divert systemic venous return to pulmonary artery when it is necessary to surgically convert the right ventricle to a systemic ventricle (eg, hypoplastic left heart syndrome[B]).