Unusual cause of absent pulse in one arm: Isolated subclavian artery.

Isolated origin of the subclavian artery is a congenital anomaly of the aortic arch in which one subclavian artery originates from the homolateral pulmonary artery through the ductus arteriosus. Isolated right subclavian artery with left-sided aortic arch is extremely rare. We report a case of isolated right subclavian artery from the right pulmonary artery via a right-sided ductus arteriosus in a 4-year-old girl. The child presented with subclavian pulmonary steal with perfusion of the right arm and lung from the right vertebral and carotid arteries. She underwent successful surgical repair.