Long-term outcomes after the arterial switch operation

The aims of this study were to evaluate the 16-year experience with  arterial switch operation at Beijing Children's Hospital and to determine early and late mortality and late morbidity, to explore risk factors for late complications and reintervention, and finally to evaluate whether the neoaortic sinotubular junction reconstruction technique reduces late complications of arterial switch operation.

The clinical data of 185 patients with transposition of the great arteries who underwent arterial switch operation in Beijing Children's Hospital from January 2006 to January 2022 and 30 patients who underwent modified arterial switch operation with neoaortic sinotubular junction reconstruction technique in Fuwai Hospital during the same period were retrospectively analysed. Propensity score matching was also used to match the neoaortic sinotubular junction reconstruction patients in Fuwai Hospital with 30 non-neoaortic sinotubular junction reconstruction patients in Beijing Children's Hospital.

There were 13 early deaths (7.03%) and five late deaths (3.01%). Nineteen patients (11.45%) developed new aortic valve regurgitation and 28 patients (16.87%) developed aortic root dilation. Late right ventricular outflow tract obstruction occurred in 33 patients (19.88%). Late reintervention occurred in 18 cases (10.84%). Multivariate analysis showed that aorto-pulmonary diameter mismatch, previous pulmonary artery banding, and mild moderate or above new aortic valve regurgitation at discharge were independent risk factors for late new aortic valve regurgitation and aortic root dilation. Low surgical weight was an independent risk factor specific to new aortic valve regurgitation, and bicuspid native pulmonary valve was an independent risk factor specific to aortic root dilation. Older surgical age and aortic root dilation were independent risk factors for late right ventricular outflow tract obstruction. Older surgical age, operation before 2014, late right ventricular outflow tract obstruction, and late aortic root dilation were independent risk factors for late intervention. Propensity score matching showed that new aortic valve regurgitation and aortic root dilation were not followed up in the neoaortic sinotubular junction reconstruction group, while seven cases of aortic root dilation and five cases of new aortic valve regurgitation occurred in the non-neoaortic sinotubular junction reconstruction group, respectively, and the differences were statistically significant (P = 0.003; P = 0.015).

The increased incidence of new aortic valve regurgitation, aortic root dilation, and right ventricular outflow tract obstruction as children age is a major concern outcome in the future and may mean more late reintervention. neoaortic sinotubular junction reconstruction technique may reduce the incidence of new aortic valve regurgitation and aortic root dilation, and improve the late prognosis of arterial switch operation. Careful follow-up of neo-aortic valve and root function is imperative, especially in patients with aorto-pulmonary diameter mismatch, previous pulmonary artery banding, mild new aortic valve regurgitation at discharge, low surgical weight, and bicuspid native pulmonary valve structures.