Severe aortopulmonary collaterals are associated with lower transplant-free survival in patients undergoing staged single ventricle palliation.

Objective:To identify risk factors for aortopulmonary collateral (APC) development and assess the impact of severe APCs in children undergoing staged single ventricle palliation. Methods:Children undergoing a bidirectional Glenn operation between January 1, 2016, and March 31, 2021, at our center were included. All underwent angiography prior to Glenn and Fontan; APC flow was graded on a scale of 0 (no appreciable collateral flow) to 4 (severe burden). Demographic data, congenital diagnosis, clinical history, and outcomes were stratified by Glenn assessment; Fontan outcomes were stratified by pre-Fontan grade. Results:Sixty patients met the inclusion criteria, all of whom had angiographic evidence of APCs. There were 7 transplants and 9 deaths in the cohort. There were no significant differences in demographics among the patients. Right ventricular morphology was more common in patients with severe pre-Glenn collaterals (24 of 44 vs 2 of 6 vs 7 of 8; P = .014). Longer stage 1 aortic cross-clamp duration was associated with greater severity pre-Glenn (44 minutes vs 34 minutes vs 66 minutes; P = .023). Patients with grade 3 pre-Glenn collaterals more commonly required transplantation than those with grade 1 collaterals (P < .001) and had lower overall transplant-free survival than those with grade 1 (P = .005) or grade 2 (P = .04) collaterals. Conclusions:The ubiquity of APCs in this study demonstrates their prevalence in single ventricle disease. Right ventricular morphology and prolonged aortic cross-clamp duration are associated with higher burden. Greater severity was associated with decreased transplant-free survival. These data emphasize the negative long-term impact of these collaterals.