Diagnosis of intramural coronary artery in transposition of the great arteries using two-dimensional echocardiography.

BACKGROUND: An intramural coronary is an uncommon but potentially significant risk factor for transfer of the coronary arteries as part of the arterial switch operation for transposition of the great arteries. Preoperative diagnosis is advantageous because it helps prevent accidental injury to the intramural coronary artery during transection of the aortic root and excision of the coronary artery ostium from the aorta. Therefore, we investigated the reliability of two-dimensional echocardiography for detecting an intramural coronary artery in infants with d-transposition of the great arteries.

METHODS AND RESULTS: All infants with d-transposition of the great arteries who underwent echocardiography and primary surgical repair at this institution between January 1987 and June 1992 were identified by search of the cardiology data base. From this group, all patients diagnosed with an intramural coronary artery were identified by review of the echocardiographic, surgical, and autopsy reports. Among 435 infants with transposition, 29 infants were diagnosed as having an intramural coronary artery. In 27 cases, the diagnosis was confirmed at surgery or autopsy, and there were two false-positive echocardiographic diagnoses (specificity, 99.5%). Twenty of the 27 patients with an intramural coronary artery were correctly diagnosed prospectively by echocardiography (sensitivity, 75%), including 17 of 23 patients with an intramural left coronary artery or left anterior descending coronary artery and 3 of 4 patients with an intramural right coronary artery. Two primary diagnostic criteria were identified: a major coronary artery arising from the contralateral septal sinus, near the usually intercoronary commissure, and a course for this vessel within the posterior aortic wall between the great arteries, creating a "double-border" appearance. Retrospective review using these criteria identified 26 of the 27 intramural arteries with no false-positive diagnoses.

CONCLUSIONS: We conclude that coronary echocardiography is a very promising technique for detecting an intramural coronary artery in transposition of the great arteries. Careful prospective application of the identified diagnostic criteria should greatly improve the diagnostic accuracy.