Abstract 9506: Clinical Correlates and Reference Intervals for Transmitral Doppler Early Filling Velocity to Tissue Doppler Early Diastolic Velocity Ratio from Infancy to Adolescence

Abstract

Background: Transmitral Doppler early filling velocity to tissue Doppler early diastolic velocity (E/E’) ratio is an index for left ventricular (LV) filling pressure, but data on the factors affecting E/E’ ratio are limited in children. The purpose of this study is to investigate the relationships between E/E’ ratio and age, BMI z-score, LV geometry, and LV function from infancy to adolescence.

Methods: Echocardiography with tissue Doppler imaging was performed in 1049 normal subjects aged 4 months to 20 years. LV end-diastolic volume, LV mass, mass to volume ratio, ejection fraction (EF), isovolumic relaxation time (IRT) and tissue Doppler-derived myocardial performance index (MPI) were assessed.

Results: Median E/E’ ratio was 7.21 (5th to 95th percentile, 5.37 to 9.73). The E/E’ ratio in younger children (< 5 years) was significantly higher than that in older children (≥ 5 years) and decreased significantly with age (r = -0.43, p < 0.01) (Fig A). E/E’ ratio decreased significantly with BMI (r = -0.23, p < 0.01) (Fig B), however, no significant relationship between E/E’ ratio and BMI z-score was observed. There were weak but significant relationships between E/E’ ratio and heart rate (r =0.36, p < 0.01), systolic blood pressure (r =-0.20, p < 0.01), EF (r = 0.14, p < 0.01), IRT(r =-0.29, p < 0.01), and MPI(r =-0.21, p < 0.01). E/E’ ratio did not correlate with LV mass to volume ratio. Multiple regression analysis revealed that independent predictor of E/E’ ratio was age.

Conclusions: We provide the first evidence of age-related decrease in E/E’ ratio from infancy to adolescence. Age-specific reference values should be considered in the interpretation of diastolic function during childhood.