Reliability of Multicenter Pediatric Echocardiographic Measurements of Left Ventricular Structure and Function

Abstract
Background To assess the reliability of pediatric echocardiographic measurements, we compared local measurements with those made at a central facility. Methods and Results The comparison was based on the first echocardiographic recording obtained on 735 children of HIV-infected mothers at 10 clinical sites focusing on measurements of left ventricular (LV) dimension, wall thicknesses, and fractional shortening. The recordings were measured locally and then remeasured at a central facility. The highest agreement expressed as an intraclass correlation coefficient (ICC=0.97) was noted for LV dimension, with much lower agreement for posterior wall thickness (ICC=0.65), fractional shortening (ICC=0.64), and septal wall thickness (ICC=0.50). The mean dimension was 0.03 cm smaller in central measurements (95% prediction interval [PI], −0.32 to 0.25 cm) for which 95% PI reflects the magnitude of differences between local and central measurements. Mean posterior wall thickness was 0.02 cm larger in central measurements (95% PI, −0.18 to 0.22 cm). Mean fractional shortening was 1% smaller in central measurements. However, the 95% PI was −10% to 8%, indicating that a fractional shortening of 32% measured centrally could be anywhere between 22% and 40% when measured locally. Central measurements of mean septal thickness were ≈0.1 cm thicker than local ones (95% PI, −0.18 to 0.34 cm). Centrally measured wall thickness was more closely related to mortality and possibly was more valid than local measurements. Conclusions Although LV dimension was reliably measured, local measurements of LV wall thickness and fractional shortening differed from central measurements.