P1284 The role of three-dimensional echocardiography in the evaluation of geometry and function of the left ventricle in patients with chronic chagas cardiomyopathy

Abstract

Abstract BACKGROUND A hallmark of chronic Chagas" cardiomyopathy (CCC) is the early appearance of regional wall motion abnormalities of the left ventricle (LV), especially in the lateral and apical regions. The morphological and functional assessment of LV by two-dimensional (2D) echocardiography, besides depending on geometric assumptions, may not include the most affected segments. The three-dimensional (3D) method offers advantage for the quantification of chamber volumes, but its role in the assessment of patients with CCC is not well established. PURPOSE: The aim of this study is to evaluate the concordance between 3D and 2D methods in the quantification of left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) in patients with CCC. METHODS: 44 patients with CCC were selected. Seven subjects were excluded from the analysis (3 for atrial fibrillation, 1 for frequent ventricular extrasystoles, 3 for inadequate acoustic window), resulting in 37 patients. Subjects were submitted to 2D and 3D transthoracic echocardiography by a single experienced examiner following the recommendations from the chamber quantification guidelines. The concordance between the methods was evaluated using the Lin concordance correlation coefficient (CCI) and the Bland-Altman graph analysis. Descriptive analyses of the percentage of individuals reclassified as to altered or to non altered-LVEDV and LVEF values were performed using normal values of 3D as a reference. RESULTS: Age = 58 ± 12 years, 54% men. LVEF-2D = 47 ± 9% and LVEDV- 2D = 73 ± 18 ml / m². The CCI for the measurements of LVEDV and FEVE by both methods was 0.861 and 0.833, respectively. The mean difference found was 3 mL for LVEDV and 3% for LVEF. The 95% agreement limits found were (-14, 20 ml) for LVEDV and (-5; 11%) for LVEF. When assessed with 2D, 27% of individuals previously classified as having LV enlargement were reclassified as having normal LV volumes using the 3D method. Conversely, regarding LVEF, 16% of individuals considered normal by 2D were reclassified as having reduced LVEF with the 3D method. CONCLUSION: In individuals with CCC measurements of LVEDV and LVEF by 3D and 2D methods show high agreement. However, 3D evaluation allows the reclassification of 27% and 16% of the individuals regarding the presence of LV dilatation and LV systolic dysfunction, respectively. Abstract P1284 Figure. Bland-Altman plot - LVEF