Early Outcomes of the Norwood Procedure in a Reference Center in Brazil

Background: Only two papers have addressed the early outcomes of patients with hypoplastic left heart syndrome (HLHS) undergoing the Norwood operation, in Brazil. Objectives: We evaluated patients with HLHS undergoing the first-stage Norwood operation in order to identify the predictive factors for early (within the first 30 days after surgery) and intermediate (from early survival up to the Glenn procedure) mortality. Methods: Patients with HLHS undergoing the stage I Norwood procedure from January 2016 through April 2019, in our service, were enrolled. Demographic, anatomical, and surgical data were analyzed. Endpoints were early mortality (within the first 30 days after surgery), intermediate mortality ( from early survival up to the Glenn procedure) and the need for postoperative ECMO support. Univariate and multivariate analyses were performed, and odds ratios, with 95% confidence intervals, were calculated. A p-value <0.05 was considered statistically significant. Results: A total of 80 patients with HLHS underwent the stage I Norwood procedure. The 30-day survival rate was 91.3% and the intermediate survival rate 81.3%. Fourteen patients (17.5%) required ECMO support. Lower weight (p=0.033), aortic stenosis (vs aortic atresia; p=0.036), and the need for postoperative ECMO support (p=0.009) were independent predictive factors for 30-day mortality. Mitral valve stenosis (vs mitral valve atresia; p=0.041) was an independent predictive factor for intermediate mortality. Conclusion: The present study includes the largest Brazilian cohort of patients with HLHS undergoing the stage I Norwood procedure in the recent era. Our survival rates were comparable to the highest survival rates reported globally. Low body weight, aortic valve stenosis, and the need for postoperative ECMO support were independent predictors for 30-day mortality. Mitral valve stenosis was the only independent predictive factor for intermediate mortality.