Coronary arterial origins in transposition of the great arteries: factors that affect outcome. A morphological and clinical study

Objective-Transfer of the coronary arteries is crucial during the arterial switch operation for transposition, but little attention has been paid to t he position of their orifices relative to the valvar sinuses. The objective of this study was to determine the factors which are important for effecti ve transfer and to determine potential surgical significance. Design-Morphological and clinical study. Setting-Two national centres for neonatal cardiac surgery. Patients-277 patients with transposition of the great arteries. One group c omprised 88 necropsy specimens (ages ranging from 17 weeks of fetal life to 17 years old), and the other comprised 189 children undergoing surgery. Th e coronary artery orifices were inspected relative to the depth of the aort ic sinuses (vertical origin), relative to the commissures between the valva r leaflets (radial origin), and their angle of exit from the aortic wall (a ngle of origin). The data were compared with the surgical results. Results-In the necropsy specimens, the vertical origin of the arteries was at, or above, the sinutubular junction in 20%, the radial origin was paraco mmissural in 3%, and the angle of origin was not orthogonal in 7%. Those wi th high take off and paracommissural origin were all intramural. In the cli nical cases, those children with high take off, paracommissural origin or t angential origin had an increased risk at surgery. Conclusions-In 20% of hearts, high take off, paracommissural orifice, or ta ngential origin of coronary arteries is found. This may be recognised preop eratively by echocardiography and may cause technical difficulty in transfe r during the arterial switch procedure.