Surgical management of high-risk newborns with critical left ventricular outflow obstruction (LVOTO) requires complex procedures associated with significant morbidity and mortality.

We sought to compare the outcomes of the hybrid versus surgical strategies (Norwood, Ross-Konno) for the management of critical LVOTO in a contemporary non-randomized cohort of neonates considered high-risk candidates.

Retrospective review of all patients undergoing management of critical LVOTO between January 2001 and December 2008. High-risk conditions included prematurity, low birth weight, associated genetic, associated cardiac and non-cardiac pathology.
Analysis was performed based on intention to treat. End-points for outcome were early and 6-month mortality.

The cohort included 57 patients (22 hybrid and 35 surgical [31 Norwood, 4 biventricular repair]. The cohort had a median age of 4 (1-62) days, mean weight of 2.7±0.5 kgs and Aristotle comprehensive score of 18.6±2.9 Analysis of the entire cohort identified low birth weight (p=.0007) prematurity (p=.004) and organ dysfunction (p=.04) as risk factors for early death. Six-month mortality was associated with need for reintervention (p=.017) in the surgical group, and aortic atresia (p=.03) in the hybrid group. Logistic regression identified low birth weight (p=.05 OR 5.6 [0.9-34.6]), organ dysfunction (p=.05 OR 4.7[0.9-22.5]), and anatomic diagnosis (p=.03 OR 0.06[.005-.93]) as predictors of mortality for the entire cohort. There was no difference for early and mid-term mortality.

Although the hybrid approach reduces the initial surgical insult, important interstage mortality and ongoing morbidity result in similar survival than surgical strategy. Patient-related factors have a greater impact on outcome that the surgical strategy.