Survival Outcomes Following Norwood Procedure for Hypoplastic Left Heart

Prior studies evaluating the association of HLHS anatomic variants and mortality report conflicting results. Our objective was to determine if antegrade flow across the mitral within variants of HLHS with aortic atresia is associated with increased mortality compared to ventricular hypoplasia variants without antegrade mitral flow. All patients with HLHS born between 2002 and 2011 year who underwent stage I Norwood palliation with complete history and echocardiograms for patency of the mitral and aortic valves were studied. The cohort was divided into three groups: aortic atresia-mitral atresia (AA-MA), aortic stenosis-mitral stenosis (AS-MS), and aortic atresia-mitral stenosis (AA-MS). Demographic, comorbidities, and operative variables were analyzed. Analysis of variance techniques was applied for continuous variables and categorical variables. Survival analysis was performed using the Kaplan-Meier method with log-rank testing. A total of 70 consecutive patients who underwent Norwood Procedure were analyzed. There were no statistical differences in gender, birth weight, and age at time of Norwood procedure. Thirty patients had AA-MA variant, 23 had AA-MS, and 17 had AS-MS. Long-term Norwood survival was 60 % for AA-MA, 65 % for AS-MS, and 26 % for AA-MS (p = 0.043). Use of extracorporeal membrane oxygenation as well as shunt revisions was more frequent for the AA-MS compared to other variants (p < 0.05). Patient weight at time of Norwood and length of regional perfusion were the highest predictors for hospital death following Norwood procedure. The Norwood procedure for mitral stenosis and aortic atresia is more often associated with use of extracorporeal membrane oxygenation and shunt revision compared to other variants. This HLHS variant has lowest long-term survival.