Identifying Factors That May Affect Mortality of Infants with Hypoplastic Left Heart Syndrome

Abstract

1. Purpose/BackgroundHypoplastic left heart syndrome (HLHS) is a severe congenital heart defect that is fatal without surgical intervention. The CDC states that HLHS make up approximately 3% of all congenital heart defects and occur in about 3 babies per 10,000 live births. While studies have shown that survival rates are improving (5-10 year survival rate was 50-60% in 2001, 60-80% in 2014), there are still many factors that play a role in the outcome of patients born with HLHS that needs further investigation. This study aims to determine specific risk factors that may affect mortality in HLHS patients. 2. MethodsWe conducted a retrospective cohort study of patients with HLHS who underwent Norwood surgery at Cook Children’s Medical Center between January 1, 2007 and December 31, 2017. The variables included total length of intubation time (≥7 days vs.days), degree of atrial septal defect (restricted vs. intact), timing of HLHS diagnosis (prenatal vs. postnatal), and survival to initial discharge (alive vs. dead). These groups were compared using descriptive statistics and chi-square test of independence. A p-value 3. ResultsThere were 151 patients meeting study criteria and 124 (82.1%) survived to discharge. We found that patients who were intubated ≥7 days were less likely to survive to discharge (75.6% vs. 91.8%; p=0.01). RAS/IAS and timing of diagnosis was not significantly related to survival to initial discharge. 4. ConclusionThe results suggest intubation length may play a role in patient outcome and mortality, but we cannot state that there is a direct correlation from this study alone. Further analysis must be done in order to determine whether intubation length itself contributed to mortality or if confounding variables were responsible.