AVOIDANCE OF SUBAORTIC OBSTRUCTION IN STAGED MANAGEMENT OF SINGLE VENTRICLE

Background. Subaortic obstruction is a frequent accompaniment of singl e-ventricle anatomy. Most often, the aorta arises from an outflow cham ber that is connected to the single ventricle by a bulboventricular fo ramen or ventricular septal defect. This connection may be restrictive of now at birth, or may become obstructive after surgical procedures that reduce the volume work of the ventricle. Subaortic obstruction is recognized as a risk factor for reconstructive surgical procedures fo r single ventricle. Methods. To prevent the consequences of subaortic obstruction, we have routinely amalgamated the proximal main pulmonary artery with the ascending aorta and arch early in the management of t hese patients. From September 1990 through September 1994, 29 neonates and infants with single ventricle and established or potential subaor tic obstruction underwent staged reconstructive surgical procedures. T he initial operation in the newborn period was a Norwood procedure (18 patients) or a pulmonary artery band (5 patients). All survivors unde rwent a hemi-Fontan procedure at approximately 6 months. Results. Eigh teen patients have undergone a completion Fontan operation with no dea ths. Five await completion Fontan. None has subaortic obstruction, and none has pulmonary valve insufficiency that is graded more than mild. Conclusions. Early association of the proximal main pulmonary artery with the ascending aorta appears to obviate the risks and complication s associated with subaortic obstruction in patients with single ventri cle.