RESUMO
BACKGROUND: Global longitudinal strain (GLS) has several sources of variation. Strain multilayer tracking is a new tool that has not yet been validated in clinical practice. AIM: The purpose of this study was to investigate intervendor variability when measuring multilayer strain in patients receiving chemotherapy for cancer. METHODS: Patients receiving chemotherapy for cancer, who were referred for echocardiography, were included prospectively. First, the same operator performed two-dimensional echocardiography on each patient using the Vivid E9™ (General Electric, Fairfield, CT, USA) and the ACUSON SC2000™ (Siemens, Munich, Germany) ultrasound systems. Second, we assessed myocardial deformation by using their respective speckle-tracking software. Third, we compared absolute values of GLS for the two vendors in each apical view (four-, three- and two-chamber) and for each layer (endocardial, mid-myocardial and epicardial). RESULTS: Eighty patients with cancer were included prospectively between February and June 2015. For a given vendor, GLS values decreased from the endocardial layer to the epicardial layer. For a given view, GLS values obtained with the ACUSON SC2000 platform were systematically lower than those obtained with the Vivid E9 platform (P<0.0001). We observed a significant difference between the two platforms, irrespective of the layer, interlayer gradient or chamber view considered (P<0.0001). CONCLUSIONS: There was poor agreement for layer-specific strain evaluation between the Vivid E9 and ACUSON SC2000 platforms, using their dedicated software for strain multilayer assessment. These results suggest that, in clinical practice, the same system and software from the same vendor should be used for longitudinal follow-up.
