CORONARY-ARTERY OBSTRUCTION AFTER THE ARTERIAL SWITCH OPERATION FOR TRANSPOSITION OF THE GREAT-ARTERIES IN NEWBORNS

Objectives. We sought to describe a large series of coronary artery ob structions after the arterial sc-itch operation for transposition of t he great arteries and to discuss their clinical implications. Backgrou nd. Aortic root angiography and myocardial perfusion imaging yield amb iguous results regarding the fate of the coronary artery anastomoses a fter the arterial switch operation. Late death related to coronary art ery obstruction and growth of the translocated coronary arteries are o f major concern in these patients. Methods. Selective coronary artery angiography nas performed prospectively in a total of 165 children. Re sults. A total of 12 coronary occlusions, 8 major stenoses, 6 minor st enoses of the left ostium and 4 stretchings of one coronary artery wer e identified. Obstructions were more frequent in types D and E (p < 0. 001) of the Yacoub and Radley-Smith classification. Coronary obstructi on was documented in all patients with electrocardiographic and ultras ound evidence of myocardial ischemia at time of study, Early postopera tive ischemia did not predict coronary artery lesion if the patient ha d fully recovered. Persistent or delayed myocardial ischemia was highl y predictive of coronary artery lesions. The incidence of coronary art ery obstruction was very high (11 of 35) in patients operated on by a rapidly abandoned technique of single-orifice reimplantation of both c oronary artery ostia. Conclusions. Selective coronary angiography is t he most accurate means to assess coronary artery obstruction after the arterial switch operation. Precise diagnosis of coronary artery lesio ns after this operation sill help to elucidate the pathogenesis, devel op adequate therapeutic strategies and might indicate how to prevent c oronary complications after operation. (C) 1997 by the American Colleg e of Cardiology