Automatic Border Detection for Assessment of Left Ventricular Diastolic Function Among Normal Neonates: Comparison...

Doppler echocardiography is the standard noninvasive method to assess left ventricular (LV) diastolic function. Recently, automatic border detection (ABD), a method based on analysis of integrated ultrasonic backscatter, has been introduced permitting real-time, on-line assessment of LV diastolic function. A comparison of these methods in normal, full-term neonates has not been performed. Therefore, the objectives of this study were to evaluate the usefulness of ABD in the assessment of LV diastolic function among normal neonates, to compare parameters obtained with the ABD method with standard Doppler-derived indexes of diastolic function, and to assess the reproducibility of ABD measurements. We studied 17 consecutive normal neonates during natural sleep with both methods shortly after birth (mean 17.4 +/- 3.9 h) and approximately 2 weeks later (mean 14.8 +/- 2.2 days). An average of five consecutive cardiac cycles were performed. Similar to Doppler indexes, no significant change in any ABD parameter of diastolic function occurred between the early and later studies. A complete ABD study could be performed within 5 minutes. Mean interobserver variation for individual ABD measurements ranged from 0% to 11%. Compared with Doppler, rapid filling fraction was greater and atrial filling fraction was less with ABD. Regression analysis showed poor correlation of these parameters between methods, but their ratio by each method remained constant between studies. A similar poor correlation existed between peak E wave velocity by Doppler and peak rapid filling rate by ABD and between peak A wave velocity by Doppler and peak atrial filling rate by ABD. These differences may be explained by technical factors and different aspects of diastolic filling assessed by each method. This study indicated that ABD was a feasible and reproducible method compared with Doppler echocardiography for serial evaluation of LV diastolic function among neonates.