A Phase 4, Open-Label, Non-Randomized, Multicenter Study to Evaluate Efficacy (and Safety) of Intravenous...

Contrast-enhanced echocardiography (CE-echo) is commonly used in adult patients to optimize endocardial border delineation (EBD) but there is limited experience in children. A prospective, open-label, non-randomized, multicenter study was performed to evaluate the efficacy of intravenous Optison for CE-echo in pediatric patients and determine the optimal dose of Optison. Subjects ≥ 9 and < 18 years with suboptimal echocardiograms (defined as ≥ 2 contiguous segments that could not be adequately visualized) were enrolled. After a baseline non-contrast echocardiogram (NC-echo), CE-echo was performed with 2 dose levels of Optison based on patient weight. The primary endpoint was visualization of the LV wall segments (LVWS) in apical 2- and 4-chamber views. An EBD score was calculated by assigning a value from 0 (no visualization) to 3 (optimal visualization) for 12 LVWS. 37 subjects across 8 sites completed the study. 30 had complete echocardiograms at both dose levels. 2 patients had usable images at dose 2 only. Mean age was 13.4 years (± 2.6) with 23 males (62%). Mean weight was 73.9 kg (± 36.8) with wide distribution of weight (interquartile range of 42-102 kg). There were 8 patients under 40 kg. Most subjects had a prior medical/surgical history (n = 33, 89%). Both dose levels of Optison CE-echo improved the number of LVWS visualized from 3.7 ± 1.1 on NC-echo to 10.0 ± 0.1 with dose 1 (p < 0.001) and 10.5 ± 0.1 with dose 2 (p < 0.001). EBD score also improved at both dose levels from 11.9 ± 2.5 for NC-echo to 28.5 ± 1.7 for dose 1 (p < 0.001) and 30.2 ± 8.4 for dose 2 (p < 0.001). The number of suboptimal echocardiograms improved from 92.3% ± 10.7 in NC-echo to 26.2% ± 9 with dose 1 (p < 0.001) and 30.8% ± 4.5 with dose 2 (p < 0.001). CE-echo with intravenous Optison in pediatric patients improved the number of LVWS visualized, improved EBD score, and reduced the number of suboptimal echocardiograms at both dosages used in this study. Intravenous Optison can improve LV visualization in pediatric patients with suboptimal echocardiograms.