Abstract 12040: Pediatric Heart Network Echocardiographic Z Scores: Comparison to Other Published Models

Introduction: Different allometric methods have resulted in variable Z scores for an echo measurement. The Pediatric Heart Network (PHN) recently established a database of echo measurements from 3215 healthy children. This study compared frequently used Z score models when applied to the PHN database. Methods: Z-scores were derived for the echo measurements using 4 models (PHN, Boston, Italy, Detroit). Model comparisons were performed for each measurement by evaluating 1) graphs of measurement vs body surface area (BSA) for each model with lines at Z = -2, 0, +2; 2) correlation coefficients for PHN vs other Z scores; and 3) median Z scores for each model. Because interobserver variability for echo measurements has been reported as ≥5% difference, median Z score differences between models representing <5% difference in measurement value were considered clinically insignificant. Results: Model characteristics are listed in the Table. For most measurements, the PHN Z score lines were similar to the Boston an...