Congenital bilateral subclavian steal: ductus-dependent symptoms in interrupted aortic arch associated with ventricular septal defect

Isolated right subclavian artery, interrupted aortic arch, and ventricular septal defect

Isolated subclavian artery is extremely rare. The clinical and hemodynamic manifestations depend on the state of ductus arteriosus, pulmonary vascular resistance, and associated intracardiac and extracardiac malformations. We discuss 2 such cases in association with an interrupted aortic arch and ventricular septal defect.

Bilateral ductus arteriosus (or remnant): an analysis of 27 patients

Bilateral ductus arteriosus (DA) was clinically recognized in 27 patients studied angiographically from 1963 through May 1983. Distal bilateral DA origin of non-confluent pulmonary arteries was identified in 15 patients, ectopic or distal ductal origin of 1 pulmonary artery in 9 patients (5 without evidence of intracardiac disease) and isolation of the left subclavian artery in 3 (all 3 of whom had a right aortic arch). Other conditions reported to be associated with bilateral DA include interruption of the aortic arch with isolation of a subclavian artery, aortic atresia with interruption of the aortic arch in which bilateral DA supports the entire systemic circulation, bilateral DA complicating forms of congenitally malformed hearts other than those just stated, and, rarely, bilateral DA in isolation. Understanding the symmetric or paired nature of the primitive aortic arch system in the developing human heart facilitates recognition of the patterns of fourth and sixth arch anomalies seen with bilateral DA.

The ductus arterious and associated cardiac anomalies in interruption of the aortic arch

Seventeen heart specimens with aortic arch interruption, a ductus-dependent anomaly, were investigated. In all specimens the cardiac anatomy favoured a preferential flow into the pulmonary artery (from which the blood could reach the descending aorta through the ductus). Ten specimens had the interruption proximal to the left subclavian artery (type B) and nine of these presented solely with an outflow tract septal defect. On the other hand, six of seven specimens with the interruption distal to the left subclavian artery (type A) were associated with more complex heart malformations. The ductus was studied histologically in the 12 available arches without surgical intervention. The structure of the ductal wall, the components of which could extend considerably into the descending aorta and the pulmonary artery, ranged from that seen in a normal, mature ductus with prominent intimal cushions, to a totally abnormal persistent type with no intimal cushions and with marked elastification. This variability in ductal wall structure and the distribution of ductal tissue in the descending aorta and pulmonary artery has clinical and surgical consequences.

Interruption of the aortic arch with right descending aorta. A rare condition and a cause of bronchial compression

Four cases of interruption of the aortic arch with the rare association of right ductus arteriosus and right descending aorta are described. Three different variations in subclavian arterial origin are described. Each represents a mirror image of anatomic arrangements previously reported for interruption of the aortic arch with left descending aorta. One of the cases demonstrated massive emphysema of the right lung resulting from compression of the right main bronchus by the enlarged right ductus arteriosus. Another case documented unusually long survival (26 years) of a patient with interruption of the aortic arch and ventricular septal defect.