Comparative Reproducibility of Myocardial Work and Left Ventricular Ejection Fraction in Patients After an Acute Coronary Syndrome.

Abstract

Purpose: To assess reproducibility (interobserver variability and agreement) of global work efficiency (GWE) and left ventricular ejection fraction (LVEF), assessed by 2D-echocardiography (2-DE) and 3D-echocardiography (3-DE), in patients with acute coronary syndrome (ACS), through measurements performed by operators with different levels of experience.

Methods: Echocardiographers with three levels of experience were involved in offline processing: advanced, who performed image acquisition-Reader 1 (5 years of training in 2-DE, 3 years in 3-DE); intermediate-Reader 2 (3 years of training in 2-DE, 1 year in 3-DE); and beginner-Reader 3 (1 year of training in 2-DE, 3 months in 3-DE). Measurements of GWE and LVEF were performed independently. Intraobserver and interobserver variability and agreement between readers were compared using Bland-Altman plots, as bias and limits of agreement (LOA), and Pearson correlations.

Results: 90 patients (54 ± 9 years, 75 males) with ACS were analyzed. Comparing measurements of GWE, the following bias and LOA were obtained: R1 versus R2: bias -0.6, LOA -3-2 (r = 0.98, p < 0.001); R2 versus R3: bias -0.3, LOA -3-5 (r = 0.96, p < 0.001); R1 versus R3: bias -1, LOA -5-4 (r = 0.94, p < 0.001). Interobserver variability and agreement of GWE were comparable with LVEF by 3-DE: R1 versus R2: bias 0.6, -2, and -1.4; LOA -3-4, -7-4, and -6-4, respectively (r = 0.96, 0.91, and 0.94, respectively, all p < 0.001); however, for LVEF by 2-DE, interobserver variability was higher, while agreement was lower.

Conclusion: Reproducibility of GWE in patients after an ACS is independent of the experience of the operator and similar to the reproducibility of LVEF by 3-DE.