Relationship of pulmonary artery size and venovenous collaterals during staged single ventricle reconstruction and their impact on outcomes after Fontan procedure.

OBJECTIVES

This study aimed to evaluate the relationship between pulmonary artery size and venovenous collaterals (VVCs) during staged single ventricle reconstruction.

METHODS

Patients who underwent staged Fontan palliation between 2003 and 2023 were reviewed. The relationship between the pulmonary artery index and the development of VVCs was determined. Furthermore, the impact of pulmonary artery index and VVCs on in-hospital morbidities after the Fontan procedure was evaluated.

RESULTS

A total of 377 patients were included. Median age at bidirectional cavopulmonary shunt (BCPS) and total cavopulmonary connection (TCPC) were 4.2 (3.3-6.2) months and 2.1 (1.7-2.6) years, respectively. VVCs were observed in 51 (13.5%) of the patients. Patients who developed VVCs showed higher pulmonary artery pressure (P = 0.024), higher transpulmonary gradient (P = 0.042), lower pulmonary artery index (P = 0.016) and lower right pulmonary artery index (P = 0.011) at the time of BCPS, compared to those without. However, the pulmonary artery index was similar in patients with and without VVCs at the time of TCPC. Higher transpulmonary gradient (P = 0.007) and lower pulmonary artery symmetry index (P = 0.032) at BCPS were identified as independent risks for developing VVCs. The existence of VVCs did not influence the postoperative course after TCPC. Notably, pulmonary artery symmetry index at BCPS was identified as an independent risk for prolonged pleural effusion (P = 0.018) and for chylothorax (P = 0.021).

CONCLUSIONS

A small and unbalanced pulmonary artery at BCPS is associated with the postoperative development of VVCs.