Abstract 142 Poster Session III, Monday, 5/3 (poster 146)

Ebstein's anomaly is a rare congenital cardiac malformation characterized by tricuspid valve deformation and displacement. The natural history of this disease is extremely variable, but symptomatic presentation in the neonatal period has been associated with a high mortality rate of ≈50%. Prior studies suggest that outcome in neonates may be related to the degree of tricuspid valve displacement (TVD), severity of tricuspid regurgitation (TR), cardiothoracic (CT) ratio, associated cardiac defects and oxygen saturation (SaO2). We retrospectively reviewed our institutional experience over the 10-year period between January 1988 and December 1997. Medical and surgical records, admission chest radiographs and echocardiograms were reviewed for 20 consecutive neonates (10 male, 10 female) who ranged from 0 to 6 days old on admission. Clinical and echocardiographic variables were assessed to determine if any could be used to predict the decision to proceed with surgical intervention. Chi square and Wilcoxon Rank Sum were utilized to perform bivariate analysis of categorical data. Student t test was utilized for continuous data. Except where noted, data are presented as mean±95% confidence interval. Admission weight was 3.5±0.3 kg (range 2.6 to 5.4 kg), CT ratio was 79±5% (range 58 to 96%), initial SaO2 was 83±4% (range 56 to 91%) and median hospital stay was 15 days (range 2 to 67 days). The median TVD was 2.25 and the median TR was 2.5 (0=none, 1=mild, 2=moderate and 3=severe). There were associated anatomic cardiac lesions (excluding patent ductus arteriosus) noted in 9 patients (45%); 6 with a ventricular septal defect (30%), 6 had pulmonary stenosis or atresia (30%) and 2 had a hypoplastic trabecular portion of the right ventricle (10%). Surgery was performed in the neonatal period in 11 patients (55%); 6 of those (55%) underwent tricuspid valve closure and shunt (with or without pulmonary valvotomy or pulmonary artery ligation), 4 (36%) underwent shunt placement alone and 1 patient (9%) was completely repaired. There was 1 early death (within the first month) giving an overall early mortality of 5%. Severe tricuspid displacement and associated cardiac lesions were statistically significant, independent predictors for surgery (p≤0.01, odds ratio=21.3). Furthermore, in patients without associated cardiac lesions, severe tricuspid displacement was found to have a 100% negative predictive value and 75% positive predictive value for neonatal surgical intervention. We conclude that: 1) Early mortality from neonatal Ebstein's anomaly is dramatically improved in the current era; 2) No identifiable risk factors reliably predict mortality in this population with complex congenital heart disease; 3) The presence of associated cardiac lesions and severe tricuspid valve displacement are possible predictors of the need for surgical palliation in the newborn period.