Proof of Concept: Favorable Outcome of Double Switch Operation (DSO) in Congenital Corrected Transposition of the Great Arteries (ccTGA) when Predefined Criteria Are Met

Objectives: Literature proposes different criteria to identify good DSO candidates. This study tried to proof this concept and find predictors for favorable outcome.

Methods: A retrospective review of all ccTGA patients undergoing DSO between 2000 and 2019 was performed. Preoperative and intraoperative characteristics, as well as early and mid-term outcome measures were analyzed. Patients were followed by echocardiography from baseline to last follow-up. Criteria to pursue with DSO were: left ventricular (LV) ejection fraction (EF) >  55%, mitral valve regurgitation ?mild, LV mass (indexed) ≥ 40 g/m² and LV mass/volume ratio >  0.9. Freedom from death and reoperations were observed using Kaplan–Meier time-to-event models. Cox’s regression analysis was performed to evaluate independent risk factors for inferior outcome.

Results: A total of 25 patients were included. Median age was 1.8 years (range: 0.4–18.3), 64% were males and median weight at surgery was 10.2 kg (range: 5.2–57). Mesocardia was found in three and dextrocardia in five patients. A large nonrestrictive ventricular septal defect was present in 84%, LVOTO in 44%, pulmonary stenosis in 28% and pulmonary atresia (PA) in 24%. Palliation prior to DSO was performed in 72%. Median preoperative LV EF% was 60% (55.5–64), median indexed LV mass was 50 g/m² (39–68.5) and median LV mass/volume ratio was 1.3 (1–1.5). Half of all patients (48%) underwent arterial switch operation (ASO) combined with Senning procedure, 20% underwent combined Rastelli and Senning procedures 20% truncal turn and Senning and 12% ASO/Rastelli + Mustard/Hemi-Mustard/Half-Senning. Median ICU and hospital stay were 7 (4.8–11.5) and 16.5 (12–21.3) days. There was one hospital death (4%). Two late deaths (8%) occurred during a median follow-up time of 28.8 months (3.5–73.3): one patient died within the first year after discharge due to severe pulmonary venous baffle stenosis and systemic pulmonary hypertension, another one died after pulmonary valve reoperation. Freedom from surgical reinterventions was 80%. Preoperative PA was the only independent risk factor associated with higher mortality and reinterventions (HR = 7.2, p = 0.03).

Conclusion: When predefined criteria are met, DSO for ccTGA with complex anatomy is associated with excellent early and acceptable midterm outcome. Patients with preoperative PA are at higher risk.

No conflict of interest has been declared by the author(s).