The significance of pulmonary annulus size in the surgical management of transposition of the great arteries with ventricular septal defect and pulmonary stenosis.

OBJECTIVE: Aortic translocation has received growing attention in the management of complete transposition with ventricular septal defect and pulmonary stenosis, but the criteria regarding pulmonary stenosis for selecting this option have yet to be established. The aim of this study is to evaluate the significance of pulmonary annulus size with the outcome after the arterial switch operation.
METHODS: Between November 1996 and September 2008, 250 patients underwent the arterial switch operation for complete transposition. Among them, 8 patients with a pressure gradient greater than 30 mm Hg, bicuspid pulmonary valve, and an aortic Z-score of the pulmonary annulus less than 0 were included in this retrospective study. The median age was 19.1 months (range, 0.5-80.0 months). The median follow-up was 39.7 months (range 9.1-139.5 months).
RESULTS: At latest follow-up, the Z-score of the neoaortic annulus increased from -1.50 + or - 1.13 (range, -3.42 to -0.35) to 1.10 + or - 1.15 (range, -0.8 to 2.10) (P < .01). No patient had a significant pressure gradient across the left ventricular outflow tract. There was 1 early death and there were no late deaths. Two reoperations were performed in 1 patient for neoaortic stenosis at 81 months and 110 months after the operation. Latest echocardiogram revealed grade 0 or 1 neoaortic insufficiency.
CONCLUSION: It was possible to extend the indication for the arterial switch operation with acceptable outcome to the patient with a Z-score of about -3 of the pulmonary annulus despite bicuspid pulmonary valve. Inasmuch as the arterial switch operation has benefits over the other options, a large-scale study is required for more reasonable triage in this group of patients. Copyright 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.