Comparison of Late Results of Arterial Switch Versus Atrial Switch (Mustard Procedure) Operation for Transposition of the Great Arteries

Abstract

Two decades after surgery for transposition of the great arteries, the clinical status, cardiac function, cardiorespiratory performance, and neurohormonal activity of patients who underwent either atrial switch (Mustard) operations or arterial switch operations (ASOs) were compared. Sixty-two patients with simple transposition of the great arteries who underwent either Mustard (n= 34) or ASO (n= 28) procedures were included in this cross-sectional study. Following the same study protocol, clinical workup including echocardiography, stress testing, and blood work was completed for all patients. Mean ages in the 2 groups were comparable, at 20.6 ± 2.1 and 20.6 ± 3.4 years in the ASO and Mustard groups, respectively. All ASO patients were in New York Heart Association class I, whereas 59% of Mustard patients were in class II or III. Peak oxygen uptake was higher in ASO patients (percentage of predicted 80% vs 69%, p <0.01). Compared with healthy subjects, the mean Tei index for systemic ventricle was high in the 2 groups, but this parameter was significantly higher in Mustard than ASO patients (0.60 ± 0.16 vs 0.47 ± 0.14, p <0.01). The median plasma N-terminal pro-brain natriuretic peptide level in ASO patients was within the normal range, but the Mustard group had significantly higher levels (42 ng/ml [range 18 to 323] vs 172 ng/ml [range 26 to 1,018], p <0.0001). In conclusion, this cross-sectional assessment 2 decades after surgery reveals better clinical status in patients who underwent ASO compared with Mustard patients. This holds in terms of cardiac function, cardiorespiratory performance, and neurohormonal activity.