Hybrid Strategy for Neonates With Ductal-Dependent Systemic Circulation at High Risk for Norwood.

Background: Hypoplastic left heart syndrome and other cardiac lesions with ductal-dependent systemic circulation continue to be challenging to manage, especially in high-risk (HR) populations (those with prematurity, multiple congenital anomalies, moderate to severe tricuspid regurgitation, hemodynamic instability, intact atrial septum).

Methods: A retrospective study on our institution's experience implementing a hybrid strategy as initial palliation in HR patients with ductal-dependent systemic circulation in HR patients undergoing Norwood versus hybrid procedure. From July 2004 to May 2008, 16 HR patients underwent stage I Norwood procedure. After implementation of a hybrid strategy in 2008, 24 HR patients underwent hybrid procedure from May 2008 to November 2015.

Results: There was no difference in gestational age, age at procedure, or hospital length of stay. The HR Hybrid group had lower mean weight (2.6 kg vs 3.1 kg, p = 0.026). Thirty-day mortality was lower in the HR Hybrid group (4% vs 31%, p = 0.019), although there was no difference in interstage mortality (17% vs 9%, p = 0.396). Catheter-based reintervention was more prevalent in the HR Hybrid group, but did not have a negative impact on survival. One-year transplant-free survival was similar (p = 0.416). HR Hybrid patients weighing less than 2.6 kg had higher overall survival (83% vs 25%, p = 0.013), as did patients who were premature (70% vs 0%, p = 0.003).

Conclusions: In high-risk patients, the hybrid procedure appears to have lower 30-day mortality and may have a survival benefit in premature patients and those less than 2.6 kg. Long-term attrition in this high-risk population is ongoing regardless of early strategy.