Speckle tracking echocardiography in detecting myocardial deformation and the influence of cardiovascular factors

The Transthoracic Echocardiogram studies the mobility of the left ventricular wall through the ejction fraction. Speckle Tracking is a recente modality that assess the function through the relative changes in the extent/thickness of the myocardium to the original shape (strains). This dissertation is divided into a systematic review and meta-analysis, and a research study. The systematic review aims to compare patients with cardiac entities and healthy individuals, in the diagnosis of LV myocardial deformation through EF values and strains. The main objective of the investigation study is to compare EF and strains in the diagnosis of LV myocardial deformation, in patients with eletrocardiographic changes or clinical histoty of cardiac enteties. Secondary objectives include (1) verify diferences between the alternations in ventricular repolarization, according to EF and strains; (2) analyse between LV segments with hypokinesia, according to EF and strains; (3) verify the correlation between age and strains; (4) describe the distribution of strains according to gender; (5) evaluate the influence of cardiovascular risk factos on strain values. Observational studies were searched in three electronic databases (PubMed, B-on, MDPI). Reviewers independently extracted data and assessed the quality of evidence with GRADE. Pooled studies were analyzed using a random effects model and results were presented as standardized mean diferences. The reseach included 22 patients who, due to electrocardiographic changes, complaints, or clinical history, were evaluated using the Speckle Tracking method. The applications of statistical techniques included summary statistical measures and graphics within the scope of descriptive statistics normality tests, homogeneity tests, independente t-tests, Mann-Whitney, Kruskal-Wallis, and ANOVA. Fifty-six articles met the inclusion and review criteria; 10 articles were grouped in meta-analysis. The combined mean of ejection fraction and strains was significantly lower in patients with cardiomyophaty (EF (-1,47 [-2,55; -0,39]), GLS (-2,18 [-3,01; -1,34])), GRS ((-1,56 [-2,48; -0,64])) myocardial infarction (EF (-2,63 [-3,64; -1,61]), GLS (2,80 [-4,10; -1,51])), and coronary artery disease (EF (-0,25 [-0,49; -0,01]), GLS (-0,95 [-1,65; -0,25])) when compared to control groups. In the 22 patients studied, the ejection fraction values compared to the strain values did not show concordant degrees of severity. Non-specific changes in ventricular repolarization and non-recent necrosis showed a difference in the GLS (p˂0,05). The middle third of the septal segment and the latero-apical segment also presented a difference in the EF (p˂0,05). When assessing the influence of cardiovascular risk factos, no evidence of a difference was found in strain values. In conclusion, speckle Tracking is a recente method that can be used to assess left ventricular myocardial function