Right Coronary Artery May Grow Even Better than Normal After Arterial Switch Operation for Complete Transposition of the Great Arteries

Abstract Background: It is unclear if coronary arteries properly grow in patients who underwent arterial switch operation for complete transposition of the great arteries. The purpose of this study was to clarify the mode of coronary growth and size in these patients. Methods: Eighteen patients who underwent arterial switch operation for complete transposition of the great arteries from 2000 to 2012 in our institution, and in whom coronary angiography was performed in late operative phase, were enrolled in this study. Growth of coronary arteries was evaluated by cubage of coronary arteries based on analyses with coronary angiography. Coronary arteries were divided into small segments and each segment was approximated by a truncated right circular cone. The sum of the cubage of each truncated cone in one coronary artery was approximated as total cubage of the coronary. the coronary cubage index was then calculated by dividing total cubage of a coronary artery by the patient’s body surface area. The coronary cubage indexes of the enrolled patients were compared with that of control patients with healed Kawasaki disease.Results: The left coronary cubage indexes of the complete transposition of the great arteries group and the control group were 1.05 ± 0.34 and 0.94 ± 0.34 (p=0.598), respectively, and no significant deference was found between groups. On the contrary, the right cubage index of the complete transposition of great arteries group was significantly larger than the control group (1.08 ± 0.44 and 0.54 ± 0.37, respectively; p=0.007), and total coronary cubage index (left coronary index + right coronary index) of the complete transposition of the great arteries group was also larger than the control group as well (2.13 ± 0.7 and 1.47 ± 0.6, respectively; p=0.026).Conclusion: The left coronary arteries after arterial switch operation for complete transposition of great arteries grow as large as normal; however, the right coronary arteries possibly grow even larger.