ABSTRACT
BACKGROUND: Chagas heart disease has a high socioeconomic burden, and any strategy to detect early myocardial damage is welcome. Speckle-tracking echocardiography assesses global and segmental left ventricular (LV) systolic function, yielding values of two-dimensional strain (ε). The aim of this study was to determine if patients with chronic Chagas disease and normal LV ejection fractions present abnormalities in global and segmental LV ε. METHODS: In this prospective study, patients with Chagas disease with no evidence of cardiac involvement (group I; n = 83) or at stage A of the cardiac form (i.e., with changes limited to the electrocardiogram) (group A; n = 42) and 43 control subjects (group C) underwent evaluation of global and segmental LV ε by speckle-tracking echocardiography. A subset of randomly selected patients in group A underwent cardiac magnetic resonance imaging and repeated echocardiography 3.5 ± 0.8 years after the first evaluation. RESULTS: Mean age, chamber dimensions, and LV ejection fraction were similar among the groups. Global longitudinal (group C, -19 ± 2%; group I, -19 ± 2%; group A, -19 ± 2%), circumferential (group C, -19 ± 3%; group I, -20 ± 3%; group A, -19 ± 3%), and radial (group C, 46 ± 10%; group I, 45 ± 13%; group A, 42 ± 14%) LV ε were similar among the groups. Segmental longitudinal, circumferential, and radial LV ε were similar across the studied groups. Seven of 14 patients had areas of fibrosis on cardiac magnetic resonance imaging. Patients with fibrosis had lower global longitudinal (-15 ± 2% vs -18 ± 2%, P = .004), circumferential (-14 ± 2% vs -19 ± 2%, P = .002), and radial LV ε (36 ± 13% vs 54 ± 12%, P = .02) than those without cardiac fibrosis despite similar LV ejection fractions. Patients with fibrosis had lower radial LV ε in the basal inferoseptal wall than patients without cardiac fibrosis (27 ± 17% vs 60 ± 15%, P = .04). CONCLUSIONS: Patients with chronic Chagas disease and normal global and segmental LV systolic function on two-dimensional echocardiography had global and segmental LV ε similar to that of control subjects. However, those in the early stages of the cardiac form and cardiac fibrosis had lower global longitudinal, circumferential, and radial LV ε.
Subject(s)
Chagas Cardiomyopathy/diagnostic imaging , Chagas Cardiomyopathy/epidemiology , Echocardiography/statistics & numerical data , Stroke Volume , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/epidemiology , Adult , Brazil/epidemiology , Comorbidity , Female , Humans , Magnetic Resonance Imaging, Cine/statistics & numerical data , Male , Prevalence , Reproducibility of Results , Risk Factors , Sensitivity and SpecificityABSTRACT
PURPOSE--To compare the doses of 750,000 and 1.5 million units (U) of streptokinase (SK), relatively to the left ventricular (LV) systolic function analyzed through contrasted ventriculography. METHODS--We included 110 patients with acute myocardial infarction (AMI) within 6h of the onset (mean-age 60 years, 83.6 men), that were randomized to receive 750,000U of SK in 15 min (55 patients), or 1.5 million U in 30 min (55 patients). The study main goal was the comparison between the groups relatively to LV ejection fraction, global and regional shortening, obtained at the fifth day of the AMI. RESULTS--The 750,000 and 1.5 million groups were homogeneous relatively to 15 analyzed variables. Relatively to the main goal of the study, it was found respectively: a) ejection fraction analysis (median): 64 and 60.5 for the total population (p = 0.25, 95 CI -2.7 to 10), 64 and 57.5 for anterior AMI (p = 0.2, 95 CI -3.6 to 16.3), 65 and 65 for inferior AMI (p = 0.99, 95 CI -8.4 to 8.4); b) global shortening analysis: -2.53 and -2.66 for the total population (p = 0.3, 95 CI -0.47 to 0.87), -2.27 and -2.53 for anterior AMI (p = 0.18, 95 CI -0.3 to 1.4), -1.82 and 1.72 for inferior AMI (p = 0.9, 95 CI -0.82 to 0.75); c) regional shortening analysis: anterior AMI -2.6 and -2.67 (p = 0.47, 95 CI -0.7 to 1.5), inferior AMI -2.3 and -2.32 (p = 0.9, 95 CI -0.82 to 0.75). CONCLUSION--The dose of 750,000U was as efficacious as the 1.5 million relatively to LV systolic function, one of the best survival predictors of short-medium and long-term survival post AMI.
Objetivo −Comparar as doses de 750.000 e 1,5 milhão de unidades (U) de estreptoquinase (EQ), em relação à função sistólica do ventrículo esquerdo (VE), analisada através da ventriculografia contrastada. Métodos − Incluíram-se 110 pacientes com infarto agudo do miocárdio (IAM) <6h de evolução (idade mediana 60 anos, 83,6% homens) que receberam, aleatoriamente, 750.000U de EQ em 15min (55 pacientes), ou 1,5 milhão em 30min (55 pacientes). A meta principal do estudo foi a comparação entre os grupos em relação à fração de ejeção (FE), encurtamento global e regional do VE, obtidas no 5º dia do IAM. Resultados − Os grupos 750.000 e 1,5 milhão mostraram-se homogêneos em relação a 15 variáveis analisadas. Em relação à meta principal do estudo, encontraram-se, respectivamente para os grupos: a) análise da FE (mediana): 64% e 60,5% para o total da população (p=0,25, 95% IC -2,7 a 10), 64% e 57,5% para os IAM anteriores (p=0,2, 95% IC -3,6 a 16,3), 65% e 65% para os IAM inferiores (p=0,99, 95% IC -8,4 a 8,4); b) análise do encurtamento global: -2,53 e -2,66 para o total (p=0,3, 95% IC -0,47 a 0,87), -2,27 e -2,53 para os IAM anteriores (p=0,18, 95% IC -0,3 a 1,4), -1,82 e -1,72 para os IAM inferiores (p=0,9, 95% IC -0,82 a 0,75); c) análise do encurtamento regional: IAM anterior -2,6 e -2,67 (p=0,47, 95% IC -0,7 a 1,5), IAM inferior -2,3 e -2,32 (p=0,9, 95% IC -0,82 a 0,75). Conclusão − A dose de 750.000U mostrou-se tão eficaz quanto a de 1,5 milhão no que se refere à função sistólica do VE, um dos melhores preditores de sobrevida a curto, médio e longo prazos pós IAM