Comparison of right ventricle–pulmonary artery shunt position in the Single Ventricle Reconstruction trial

Objective Placement of a right ventricle–pulmonary artery shunt to the left or right of the neoaorta may influence reinterventions, pulmonary artery development, and survival after the Norwood procedure because of differences in shunt and pulmonary artery geometry and blood flow. Methods We analyzed the Pediatric Heart Network Single Ventricle Reconstruction Trial public use dataset. Comparisons were made between patients who received a left- or right-sided right ventricle–pulmonary artery shunt during the Norwood procedure in both the overall (n = 274) and the propensity score–matched (67 pairs) patient cohorts. Results A left-sided shunt was placed in 168 patients (61%), and a right-sided shunt was placed in 106 patients (39%). At the 12-month follow-up, there were no differences in pulmonary artery measurements, hemodynamic measurements, or pulmonary artery reinterventions between shunt groups. However, the right-sided shunt was associated with fewer surgical shunt revisions in both the overall (8.3 vs 1.9 events per 100 infants, P = .05) and the propensity score–matched (17.9 vs 0 events per 100 infants, P < .001) patient cohorts. In the propensity score–matched cohort only, right-sided shunts were further associated with fewer serious adverse events (84 vs 46 events per 100 infants, P = .01) and improved transplantation-free survival at 3 years follow-up (61% [95% confidence interval, 48-72] vs 80% [95% confidence interval, 69-88], P = .04). Conclusions In the Single Ventricle Reconstruction trial, right ventricle–pulmonary artery shunt placement to the right of the neoaorta was associated with fewer shunt revisions and may contribute to improved outcomes in select patients.