Right versus left pulmonary artery anastomosis of the right ventricle-to-pulmonary artery conduit in Norwood procedure: Comparable outcomes with longer Glenn operative time.

OBJECTIVE

In the modified Norwood procedure for hypoplastic left heart syndrome, right ventricle-to-pulmonary artery (RV-PA) conduit laterality is largely surgeon dependent. We evaluated whether conduit laterality influences early outcomes and subsequent bidirectional Glenn (BDG) surgery.

METHODS

We retrospectively reviewed consecutive patients with hypoplastic left heart syndrome or hypoplastic left heart complex undergoing Norwood with an RV-PA conduit between September 2023 and March 2026. Patients were stratified according to whether the RV-PA conduit was positioned to the right (R-PA) or left (L-PA) of the reconstructed neoaorta. Early outcomes, pre-BDG hemodynamics, and BDG operative variables were compared.

RESULTS

Thirty-one patients were included (R-PA, n = 15; L-PA, n = 16). Age at Norwood (5 vs 4.5 days) and body weight (3.27 vs 3.30 kg) were similar. Early mortality (0 vs 1), extracorporeal membrane oxygenation use (1 vs 2), unplanned RV-PA conduit stenting (2 vs 1), and PA stenting (4 vs 2) did not differ between groups (all P > .05). Pre-BDG catheterization demonstrated comparable hemodynamics, including cardiac index (3.3 vs 4.0 L/min/m2), pulmonary-to-systemic blood flow ratio (1.20 vs 1.33), pulmonary vascular resistance (1.21 vs 1.59 WU), and mean PA pressure (13.5 vs 12.0 mm Hg) (all P > .05). At BDG, atrioventricular valve regurgitation greater than mild occurred in 2 patients per group, body weight and Norwood-to-BDG interval were similar. However, cardiopulmonary bypass time was significantly shorter in the R-PA (93 vs 195 minutes, P = .033).

CONCLUSIONS

RV-PA conduit laterality does not influence early Norwood outcomes or pre-BDG physiology. Left-sided conduit placement is associated with longer BDG CPB time, suggesting increased operative complexity.