8 Tetralogy of Fallot with Pulmonary Atresia
A 25-year-old white woman, gravida 3, para 2+1, was referred at 18 weeks’ gestation because of a paternal history of congenital heart disease and an abnormal five-chamber view on screening ultrasound examination (one large great vessel only).
3. The four-chamber view is normal, with an axis that is approximately 90 degrees (Fig. 8-1). However, more superior scanning shows it to be abnormal, with a large outlet perimembranous subaortic ventricular septal defect (VSD) and a large overriding aorta.
(Modified from Mullins CE, Mayer DC: Congenital Heart Disease: A Diagrammatic Atlas. New York, Liss, 1988.)
Chest films show normal heart size, decreased pulmonary venous marking, and a boot-shaped heart with a concave main pulmonary artery segment and markedly decreased pulmonary vascular markings (black lung fields) unless there is adequate flow to the lungs through the aortopulmonary collaterals.
b. If there is no ductus arteriosus, or if it is uncertain whether the branch pulmonary arteries themselves are stenotic or if the pulmonary arteries are discontinuous with uncertain source of pulmonary blood flow, the infant requires cardiac catheterization.
c. If pulmonary blood flow is via aortopulmonary collaterals and the infant has sufficient oxygen saturations, some centers do not perform cardiac catheterization in the neonatal period, but rather closer to the time of repair with unifocalization of the collaterals, perhaps at 2 to 3 months.
c. When the central pulmonary arteries are nonconfluent, with multiple collaterals supplying different segments of the lungs, unifocalization of these collaterals may be necessary at the time of complete repair or with staged reconstruction.
d. Occlusion of the systemic collateral arteries can be done by coil embolization preoperatively (transcutaneous during cardiac catheterization or intraoperatively while off cardiac bypass) and would be considered if there is an antegrade source of pulmonary blood flow through the native branch pulmonary arteries.