Multicenter comparison of hybrid and Norwood procedures in patients with Fontan circulation.

Abstract

The hybrid stage 1 palliation (HS1P) procedure has been proposed as an alternative to the Norwood operation. We utilized a multicenter database to compare both strategies. The Fontan Outcomes Registry using Clinical Examinations was queried for patients who underwent HS1P or Norwood. Propensity score matching was performed. Composite outcome (death, transplant listing, protein losing enteropathy, plastic bronchitis, atrial/ventricular tachyarrhythmia, or pulmonary artery reintervention) and cardiac magnetic resonance variables were compared. Secondary analyses compared between HS1P and shunt type (Sano vs Blalock-Thomas-Taussig). Two hundred twenty-eight patients were analyzed (76 HS1P, 152 Norwood) after exclusion and matching. Median follow-up after Fontan was 14 years (95% CI, 13.0-15.1 years) using the reverse Kaplan-Meier method. The freedom from composite outcome was 82.3%, 74.5%, and 61.2% for HS1P patients compared with 81.4%, 69.5%, and 54.7% for Norwood patients at 5-, 10-, and 15-year follow-ups, respectively (hazard ratio, 1.02; 95% CI, 0.62-1.70; P = .9305). Individual components of the composite outcome were also similar between HS1P and Norwood in the matched cohort, including pulmonary artery reintervention. Cardiac magnetic resonance and echocardiographic parameters did not differ between groups. In a 3-group analysis of the unmatched cohort (n = 954) using Blalock-Thomas-Taussig conduit as the reference, HS1P was not associated with differences in adjusted hazard for the composite outcome or its individual components compared with Blalock-Thomas-Taussig. HS1P in those who survived to Fontan completion had comparable Fontan era outcomes and cardiac magnetic resonance findings to Norwood in a propensity matched multicenter cohort. Further longitudinal work is essential to refine patient selection and to optimize long-term outcomes.