Abstract 14975: Increased Morbidity and Mortality in Patients With Hypoplastic Left Heart Syndrome and Genetic Abnormalities

Abstract

Introduction: Hypoplastic left heart syndrome (HLHS) is a genetically heterogenous, severe form of congenital heart disease. Hypothesis: Patients with reported genetic abnormalities will have worse outcomes than those without reported genetic abnormalities. Methods: This was a retrospective review of patients enrolled in the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) phase I registry. Registry enrollment occurred at discharge following stage 1 palliation. Patients were placed into one of three groups: major syndromes (Turner, Down, CHARGE, DiGeorge, Jacobsen, VATER, heterotaxy), other genetic abnormality, or no reported genetic abnormality. Demographic and clinical variables were compared using Pearson Chi-square, one-way ANOVA, or Kruskal-Wallis test. Tukey post-hoc test was applied to adjust p-values for pairwise group comparisons. Outcomes of length of stay, death, and combined outcomes of death, not a candidate for stage 2 palliation and transplant were compared among the groups. Results: Of the 2182 patients, major syndromes were reported in 110 (5%), other genetic abnormalities in 126 (5.8%) and no abnormalities in 1946 (89.2%). Those with major syndromes weighed less at birth and the time of stage I palliation, were more likely to be female and have a primary cardiac diagnosis of unbalanced AVC. Those with major syndromes or other genetic abnormalities were more likely to have moderate to severe AV valve regurgitation, moderate to severe ventricular dysfunction, arrhythmia requiring therapy, and major anomalies of other organ systems compared to those with no abnormalities. Patients with no reported genetic abnormalities reached full oral feeds sooner after the Norwood (19 vs 24 days), were more likely to be discharged on all oral feeds (75% vs 59% and 62%) and were discharged earlier (35 vs 45 and 43 days). For the outcome of death, there was no significant difference among the groups. The combined outcome of death, not a candidate for stage 2 palliation, and heart transplant was more likely in those with a major syndrome after adjusting for covariates. Conclusions: Patients with HLHS and major syndromes or other genetic abnormalities experience greater morbidity and mortality during the interstage period.