In aortic arch anomalies, vessels that encircle and compress trachea and/or esophagus are known as vascular ring malformations. The ductus arteriosus (patent or ligamentum) is an integral part of vascular rings. Side of aortic arch is determined by which bronchus it crosses, left aortic arch crosses over the left bronchus and right aortic arch crosses the right bronchus. The sidedness is diagnosed from plain chest X-ray (penetrating view), bronchogram and esophagogram, which show indentation of the trachea or the esophagus on the respective side. In echocardiography, CT, MRI and angiography, side of arch is determined by delineating the branching pattern of brachiocephalic vessels from the arch. In certain congenital heart diseases incidence of right aortic arch is high. Compressive vascular rings clinically present with respiratory distress and difficulty in swallowing.