Improving reproducibility of left ventricular ejection fraction in pediatric oncology patients: less is more.

Reproducible measurement of left ventricular (LV) systolic function by echocardiography is important to detect cancer therapy-related cardiac dysfunction (CTRCD). We hypothesized that limiting the number of imaging operators and use of a single vendor would improve reproducibility of these measures. A standard operating procedure (SOP) whereby LV measurements were standardized and a cardio-oncology imaging team (5 sonographers, 6 cardiologists) was established. All pediatric oncology patient echocardiograms were acquired on a single vendor platform. In total, 100 consecutive pre-SOP and 100 post-SOP studies were reviewed. LV end-diastolic dimension (LVEDD), posterior wall thickness (PW), shortening fraction (SF), and ejection fraction by Simpson's biplane (EF) were re-measured by 2 blinded readers, and compared to what was originally reported. Image quality was scored by number of LV segments imaged (grades 1-4). Inter-observer reproducibility pre/post-SOP was assessed with intra-class coefficient (α). Reducing the number of imaging operators improved image quality (Grade ≥ 3: 13% vs. 46%, p < 0.001). Reproducibility of PW and LVEDD marginally improved (PW: 0.78 to 0.82; LVEDD: 0.96 to 0.97), and SF improved significantly (α = 0.65 vs. 0.79, p < 0.001). Pre-SOP reproducibility of LV EF was poor (α = 0.65), but improved significantly post-SOP (α = 0.83, p < 0.001). Reproducibility of LV EF improved with higher image quality score. Limiting imaging operators and vendor platform for pediatric oncology echocardiograms improves image quality and reproducibility of LV EF. Establishing an SOP and a cardio-oncology echocardiography team may improve precision of measurements used to detect CTRCD.