A Comparative Evaluation of Transoesophageal and Transthoracic Echocardiography of The Left Ventricular Function Using Speckle Tracking Global Longitudinal Strain

Abstract

Abstract Objective: The goal of this study was to analyse the reproducibility and level of agreement of transoesophageal echocardiography (TOE) two-dimensional (2D) global longitudinal strain (GLS) in relation to transthoracic echocardiography (TTE) 2D GLS in the evaluation of left ventricular (LV) function. Background: 2D speckle-tracking imaging for TTE has been introduced in several studies as a reliable examination in the analysis of LV function. However, we cannot assume the same to be true for TOE. Design: A comparative retrospective study. Setting: The echocardiography department of Hammersmith Hospital. Methods: Twenty-five participants with significant valve diseases were included in the study. Both TTE and TOE images were recorded by Philips ultrasound machines and were evaluated offline. The GLS values were assessed from four-chamber, two-chamber and three-chamber views for both TTE and TOE. Results: The sample study had a mean age of 58 ± 14.39 years. Most of the patients were males (64%) and, from the whole population, 56% had MR. The null hypothesis was supported in this study, as there was no significant difference between TTE and TOE in assessing LV function using speckle tracking echocardiography (STE) GLS. The correlation between TOE GLS and TTE GLS was moderate (r = 0.75) in both the myocardium and endocardium. Therefore, there was an excellent agreement level between both methods, whereas reproducibility was low. Patients with mitral valve regurgitation had a higher LV volume and a lower ejection fraction (EF) in TTE GLS (-9.019 ± 3.52 vs 33.22 ± 11.19, respectively) than in TOE GLS ( -11.12 ± 4.49 vs 37.20 ± 13.72, respectively). The frame rate (FR) had higher values in TTE with more depth than in TOE (17.2 ± 1.73 vs 13.28 ± 1.72, respectively, for the depth).

Conclusion: Although the reproducibility was low in both methods, TOE 2D GLS was in good agreement with TTE 2D GLS. Therefore, the TOE 2D strain can be used in evaluating LV function. Keywords: Transthoracic echocardiography, transoesophageal echocardiography, two-dimensional global longitudinal strain, speckle tracking, left ventricular function