MARCIO SILVA MIGUEL LIMA
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- Comprehensive left ventricular mechanics analysis by speckle tracking echocardiography in Chagas disease(2016) LIMA, Marcio Silva Miguel; VILLARRAGA, Hector R.; ABDUCH, Maria Cristina Donadio; LIMA, Marta Fernandes; CRUZ, Cecilia Beatriz Bittencourt Viana; BITTENCOURT, Marcio Sommer; VOOS, Mariana Callil; SBANO, Joao Cesar Nunes; MATHIAS JR., Wilson; TSUTSUI, Jeane MikeBackground: Chagas disease (CD) is a frequent cause of dilated cardiomyopathy (CMP) in developing countries, leading to clinical heart failure and worse prognosis. Therefore, the development and evolution of this CMP has always been a major topic in numbers of previous studies. A comprehensive echocardiographic study of left ventricular (LV) mechanics, fully assessing myocardial contraction, has never been done before. This could help characterize and improve the understanding of the evolution of this prevalent CMP. Methods: A total of 47 chagasic and 84 control patients were included in this study and allocated in groups according to LV ejection fraction. 2D-Echocardiogram was acquired for LV mechanics analysis by speckle tracking echocardiography. Results: Mean age of chagasic individuals was 55y and 16 (34 %) were men. Significant difference was found in global longitudinal velocity analysis, with lower values in indeterminate form. In the group with severe systolic dysfunction, a paradoxical increase in longitudinal and apical radial displacements were demonstrated. In parallel, segmental analyzes highlighted lower values of radial displacement, strain and strain rate into inferior and inferolateral walls, with increase of these values in septal and anterior walls. Conclusion: Chagasic CMP has a vicarious pattern of contraction in the course of its evolution, defined by reduced displacement and strain into inferior and posterior walls with paradoxical increase in septal and anterior segments. Also, lower longitudinal velocities were demonstrated in CD indeterminate form, which may indicate an incipient myocardial injury.
- Global Longitudinal Strain or Left Ventricular Twist and Torsion? Which Correlates Best with Ejection Fraction?(2017) LIMA, Marcio Silva Miguel; VILLARRAGA, Hector R.; ABDUCH, Maria Cristina Donadio; LIMA, Marta Fernandes; CRUZ, Cecilia Beatriz Bittencourt Viana; SBANO, Joao Cesar Nunes; VOOS, Mariana Callil; MATHIAS JUNIOR, Wilson; TSUTSUI, Jeane MikeBackground: Estimative of left ventricular ejection fraction (LVEF) is a major indication for echocardiography. Speckle tracking echocardiography (STE) allows analysis of LV contraction mechanics which includes global longitudinal strain (GLS) and twist/torsion, both the most widely used. Direct comparison of correlations between these novel parameters and LVEF has never been done before. Objective: This study aims to check which one has the highest correlation with LVEF. Methods: Patients with normal LVEF (> 0,55) and systolic dysfunction (LVEF < 0,55) were prospectively enrolled, and underwent echocardiogram with STE analysis. Correlation of variables was performed by linear regression analysis. In addition, correlation among levels of LV systolic impairment was also tested. Results: A total of 131 patients were included (mean age, 46 +/- 14y; 43%, men). LVEF and GLS showed a strong correlation (r = 0.95; r(2) = 0.89; p < 0.001), more evident in groups with LV systolic dysfunction than those with preserved LVEF. Good correlation was also found with global longitudinal strain rate (r = 0.85; r(2) = 0.73; p < 0.001). Comparing to GLS, correlation of LVEF and torsional mechanics was weaker: twist (r = 0.78; r(2) = 0.60; p < 0.001); torsion (r = 0.75; r(2) = 0.56; p < 0.001). Conclusion: GLS of the left ventricle have highly strong positive correlation with the classical parameter of ejection fraction, especially in cases with LV systolic impairment. Longitudinal strain rate also demonstrated a good correlation. GLS increments analysis of LV systolic function. On the other hand, although being a cornerstone of LV mechanics, twist and torsion have a weaker correlation with LV ejection, comparing to GLS.