Methods: Intermediate term data (8.7 ± 1.2 months) has been retrospectively collected on the 9 survivors of neonatal RV exclusion. Echocardiographic examinations were compared from the time of the original RV exclusion and prior to second stage Glenn palliation. Measurement of the GOS ratio (area of right atrium + atrialized right ventricle / area of trabeculated RV + left atrium and left ventricle), ratio of RV to LV area, degree of ventricular septal impingement into the LV, and LV shortening fraction have been documented.

Results: In the nine survivors of RV exclusion a decrease in the mean GOS ratio was observed (pre-FRVE 1.04 ± 0.49 vs pre-Glenn 0.31 ± 0.10, p = 0.01). The average pre-Glenn RV/LV ratio was substantially lower than 1.0 (mean = 0.63 ± 0.27) demonstrating RV regression. The degree of LV septal impingement decreased by an average of 38% p=0.008, normalizing LV morphology. At the time of Glenn palliation the LV shortening fraction was normal in all patients (mean 42% ± 7%).

Conclusion: Following neonatal RV exclusion (Starnes procedure) for severe Ebstein's Anomaly there is a reduction in RV size as demonstrated by echocardiographic evidence of significant decrease in GOS ratios. This regression correlates with ventricular septal realignment and normalization of LV function.