Reliability of comprehensive echocardiography evaluation of patent ductus arteriosus among extremely preterm neonates across a national network: A prospective observational study.

BackgroundPrior studies on the reliability of targeted neonatal echocardiography (TNE) among extremely low gestational age neonates (ELGANs) with a patent ductus arteriosus (PDA) have been limited to evaluation of pre-defined images by a small set of study observers. The objective of this study was to investigate the interobserver reliability of comprehensive echocardiography measures of PDA size/shunt volume and ventricular performance among TNE-neonatologists in a large national network.MethodsWe conducted a prospective observational study. TNEs performed for the evaluation of PDA among ELGANs were analyzed by TNE-neonatologists from the Canadian TNE Consortium. Analyses were conducted via an interactive videoconferencing platform offering full remote control to the review software. Reliability for continuous measures was evaluated using the intraclass correlation coefficient (ICC) and coefficient of variation. The kappa statistic was used to evaluate the interobserver reliability of categorical parameters.ResultsReliability was excellent among indices of PDA size and gradient (ICC≥0.91) and good-to-excellent among most indices of left ventricular (LV) size and output (ICC≥0.79, except for LV end-systolic volume and left atrium to aortic root ratio). There was substantial to near-complete agreement on PDA shunt direction and diastolic flow abnormalities in the abdominal aorta and systemic arteries (kappa ≥0.78). However, reliability for measures of LV systolic and diastolic performance was variable with ICC range 0.21-0.95, though with low coefficient of variation (<15%).ConclusionsInterobserver reliability for most TNE measures of PDA size, gradient, shunt volume, and LV dimensions and function is good-to-excellent, supporting the validity of incorporating these indices in prospective multicenter research.