Coronary obstructions after reimplantation of the two coronary ostia in a single orifice during arterial switch operation for transposition of the great arteries

Abstract

Recently, a new technique for the transfer of the coronary arteries during the arterial switch operation for transposition of the great arteries in neonates has been proposed [1 ]. This technique involves reimplantation of the two coronary ostia side by side after excision of a single button of neoaortic wall. Between 1992 and 1993, 49 neonates referred to our institution for transposition of the great arteries underwent an arterial switch operation with this technique. Operative mortality was low (1/49, 2.2%) and was not related to coronary artery occlusion or twist. However, eight patients (14.3%) experienced acute ischemic complications within 4 months after surgery. Three of these eight patients died suddenly. Autopsy demonstrated severe stenosis of one or both coronary ostia in two patients. The third patient had severe left ventricular dysfunction suggestive of acute coronary ischemia. Unfortunately, postmortem examination could not be obtained. Further, selective coronary artery angiographies identified coronary artery obstructions in the remaining five survivors. This unusual rate of ischemic complications after the arterial switch operation in our experience prompted us to control the patency of the coronary arteries in these patients. Thirty-five out of the 49 (71.4%) children (mean age 1.61+1.03 years (standard deviation), mean weight 9.86-+3.74 kg (standard deviation)) had selective coronary artery angiograms. Coronary artery obstructions could be documented in 11/35 (31.4%). The patients' functional status and coronary artery lesions are shown in Table 1. The risk of coronary artery occlusion or stretching was significantly higher when one of the coronary arteries looped around one of the great vessels, namely type D and E [2] (Z2=5.226, P<0.05). In addition, 2/3 patients with type C pattern and initial