Pediatric Reference Ranges and Test Characteristics of E-point Septal Separation as a Marker for Left Ventricular...

E-point septal separation (EPSS) is a well-established quantitative point-of-care ultrasound metric for estimating left ventricular (LV) ejection fraction (LVEF) in adults. However, its utility in pediatric populations remains unclear. This study aims to evaluate the test characteristics of EPSS as a marker of LV systolic dysfunction in pediatric patients.

This single-center retrospective study included 600 pediatric patients (aged 20 y or younger) who underwent transthoracic echocardiography between January 2015 and June 2024. EPSS measurements were retrospectively obtained from stored parasternal long-axis views using M-mode. Correlations between EPSS and demographic and clinical parameters were analyzed. Diagnostic performance was evaluated using receiver operating characteristic curve analysis.

Of the 600 patients, 531 had normal LV function (control group), and 69 had LV systolic dysfunction (LVEF <55%). In the control group, EPSS significantly correlated ( P <0.01) with age, height, weight, body mass index, body surface area, systolic blood pressure, diastolic blood pressure, heart rate, and LV fractional shortening, but not with LVEF. Age-, sex-, and BSA-specific reference ranges for EPSS were established. Patients with LV systolic dysfunction had significantly higher EPSS values than controls ( P <0.01). Receiver operating characteristic analysis revealed an area under the curve of 0.93 (95% CI: 0.89-0.97) with an optimal cut-off value of 6.17 mm, yielding 86% sensitivity, 92% specificity, and a negative predictive value of 98%.

EPSS is a reliable ultrasonographic marker for identifying LV systolic dysfunction in pediatric patients and may demonstrate clinical utility in emergency settings.