Pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals: collateral vessel disease burden and unifocalisation strategies.

Introduction: The optimal approach to unifocalisation in pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (pulmonary artery/ventricular septa) defect/major aortopulmonary collaterals) remains controversial. Moreover, the impact of collateral vessel disease burden on surgical decision-making and late outcomes remains poorly defined. We investigated our centre's experience in the surgical management of pulmonary artery/ventricular septal defect/major aortopulmonary collaterals. Materials and methods: Between 1996 and 2015, 84 consecutive patients with pulmonary artery/ventricular septal defect/major aortopulmonary collaterals underwent unifocalisation. In all, 41 patients received single-stage unifocalisation (Group 1) and 43 patients underwent multi-stage repair (Group 2). Preoperative collateral vessel anatomy, branch pulmonary artery reinterventions, ventricular septal defect status, and late right ventricle/left ventricle pressure ratio were evaluated. Results: Median follow-up was 4.8 compared with 5.7 years for Groups 1 and 2, respectively, p = 0.65. Median number of major aortopulmonary collaterals/patient was 3, ranging from 1 to 8, in Group 1 compared with 4, ranging from I to 8, in Group 2, p = 0.09. Group 2 had a higher number of lobar/segmental stenoses within collateral vessels (p = 0.02). Group 1 had fewer catheter-based branch pulmonary artery reinterventions, with 5 (inter-quartile range from 1 to 7) per patient, compared with 9 (inter-quartile range from 4 to 14) in Group 2, p = 0.009. Among patients who achieved ventricular septal defect closure, median right ventricle/left ventricle pressure was 0.48 in Group 1 compared with 0.78 in Group 2, p = 0.03. Overall mortality was 6 (17%) in Group 1 compared with 9 (21%) in Group 2. Discussion: Single-stage unifocalisation is a promising repair strategy in select patients, achieving low rates of reintervention for branch pulmonary artery restenosis and excellent mid-term haemodynamic outcomes. However, specific anatomic substrates of pulmonary artery/ventricular septal defect/major aortopulmonary collaterals may he better suited to multi-stage repair. Preoperative evaluation of collateral vessel calibre and function may help inform more patient-specific surgical management.