Anatomy of the coronary arteries in transposition of the great arteries and methods for their transfer in anatomical correction.

For the success of anatomical correction of transposition of the great arteries (TGA) it is essential to transfer the coronary ostia to the posterior vessel without undue tension, torsion, or kinking of the proximal coronary arteries or their early branches. This requires thorough understanding of the different modes of origin and early branching of the coronary arteries in TGA. Based on observations made during anatomical correction, a classification of the coronary arteries in TGA is suggested. In type A the right and left coronary ostia arise from the middle of the right and left posterior aortic sinuses and curve forwards to reach the right atrioventricular groove or anterior interventricular groove respectively. In type B both coronary arteries arise by a single ostium, while in type C the two coronary ostia are situated posteriorly, very close to each other, in a position similar to that in type B. The origin of the coronary arteries in type D is similar to that of type A. However, the right coronary artery gives origin to the circumflex coronary artery that curves round the posterior (pulmonary) vessel to reach the atrioventricular groove. In type E the right coronary artery arises in common with the left anterior descending artery from the left posterior sinus, while the circumflex artery arises separately from the right posterior sinus. Three techniques for the transfer of the different types of coronary arteries during anatomical correction are described.