Isolated subclavian artery is a rare anomaly. A second steal due to a patent arterial duct further reduces arm perfusion. Surgical anastomosis of the isolated vessel to aorta normalises arm perfusion. Simple echocardiographic clues aid in the diagnosis. An associated moderate sized ventricular septal defect was non-surgically closed along with catheter closure of the duct resulting in improved arm perfusion.

Isolation of the subclavian artery is associated with “steal” of blood from the carotid circulation to the arm, through the circle of Willis and the vertebral artery. When associated with a patent arterial duct, there is an additional “steal” of blood from the arm to the lungs, through the arterial duct because of the lower pulmonary vascular resistance. When this combination manifests clinically with arm ischaemia on the side of the isolated subclavian artery, closure of the arterial duct will prevent the “steal” of blood from the subclavian artery to the pulmonary artery and may improve the blood flow to the arm. We report three patients with this unusual combination of the “steal” phenomenon that improved after interventional closure of the arterial duct. This report discusses the embryological basis of the defect, clinical and echocardiographic clues to diagnose this unusual anomaly, angiographic findings, and transcatheter management options.

We present a patient with DiGeorge syndrome and an isolated right subclavian artery arising from the right pulmonary artery via a right-sided ductus arteriosus. The patient showed a subclavian and pulmonary steal with perfusion of the right arm and right lung via retrograde circulation in the right vertebral artery. The patient underwent successful surgical repair.

Isolation of the subclavian artery is an unusual anomaly in which the subclavian artery arises not from the aortic arch but from a pulmonary artery via an arterial duct. Such isolation most often occurs with a right aortic arch, and in lesions frequently associated with a right arc, such as tetralogy of Fallot. Since1994, we have undertaken surgery in four young infants with isolated subclavian arteries and unusual associated anomalies, including one with atrioventricular septal defect and common valvar orifice, two with interruption of a left aortic arch and one with interruption of a right aortic arch. In both patients with interrupted left arch, the isolated subclavian artery was diagnosed preperatively by echocardiography. We emphasize the significant issues.

We describe two children with isolated origin of the left subclavian artery from the left pulmonary artery detected by echocardiography during the assessment of their congenital cardiac malformations. Both patients demonstrated pre-operative evidence of subclavian steal. This entity results from persistence of the dorsal segment of the sixth left arch, with regression of the left fourth arch and interruption of the left dorsal arch distal to the origin of the seventh left intersegmental artery. The significance of this finding relates to the potential for pulmonary overcirculation, which could have significant post-operative ramifications if not detected prior to surgical repair of an associated cardiac malformation. This entity differs from cases with a right aortic arch and aberrant left subclavian artery which has the potential to form a vascular ring, unlike cases with isolated origin of the left subclavian artery from the pulmonary artery that do not cause compression of the airway.