Right Aortic Arch with Bicarotid Trunk and Isolated Left Subclavian Artery: Hitherto Unreported Pattern.

Variant arch anatomy may be seen associated with many congenital heart diseases. Its accurate preoperative identification is of paramount importance in optimal surgical planning of such cases. This case describes one such variant arch anatomy with two vessel right aortic arch, comprising of bicarotid trunk (giving rise to bilateral common carotid arteries) and right subclavian artery with isolation of the left subclavian artery, in a patient with tetralogy of Fallot. Right aortic arch with isolated left subclavian artery has already been described in association with tetralogy of Fallot. However, to the best of our knowledge, present arch pattern consisting of right aortic arch with bicarotid trunk and isolated left subclavian artery has not been reported in literature so far. Moreover, this case highlights the utility of multidetector computed tomography in accurate identification of variant arch anatomy in addition to delineation of cardiac and extracardiac details.