Stage 1 hybrid palliation for hypoplastic left heart syndrome-assessment of contemporary patterns of use: An analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

Objective: Hybrid palliation is an alternative to Norwood stage 1 for the initial management of hypoplastic left heart syndrome. Contemporary multicenter hybrid use and institutional/patient factors associated with hybrid use relative to the Norwood have not been evaluated. We describe hybrid use in relation to institutional volume, patient factors, and short-term outcomes. Methods: Infants aged 60 days or less listed in The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010-2012) undergoing initial palliation of hypoplastic left heart syndrome were included. Annual institutional hybrid use rates were calculated: [hybrid procedures/(Norwood+hybrid+transplant procedures)]. In-hospital outcomes for primary hybrid and primary Norwood were compared and stratified by high (defined as ≥50%) versus low (defined as ≤10%) institutional hybrid use. Results: Of 1728 patients (100 centers), most (n = 1496, 87%) underwent an index Norwood; 232 patients (13%) underwent an index hybrid procedure. Preoperative patient risk factors were more prevalent in patients undergoing the hybrid procedure. Only 13 of 100 institutions were high hybrid users, and these tended to have lower annual hypoplastic left heart syndrome index case volume. Unadjusted in-hospital mortality was higher for the hybrid compared with the Norwood procedure (30% vs 16%; P<.001). In-hospital mortality for the hybrid procedure was not associated with hybrid use (26% among institutions with low use vs 28% among institutions with high use). However, centers with high hybrid use had higher mortality after the Norwood (43%) compared with centers with low hybrid use (16%). Conclusions: Few centers currently select the hybrid procedure for most infants with hypoplastic left heart syndrome. Although unadjusted in-hospital hybrid mortality is higher than Norwood mortality, potential risk factors are more prevalent among hybrid cases. Institutions with higher hybrid use have lower hypoplastic left heart syndrome case volume and higher Norwood mortality.