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Background: Chagas' heart disease is an important public health problem in South America. Several aspects of the pathogenesis are not fully understood, especially in its subclinical phases. On pathology Chagas' heart disease is characterized by chronic myocardial inflammation and extensive myocardial fibrosis. The latter has also been demonstrated by late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR). In three clinical phases of this disease, we sought to investigate the presence of LGE, myocardial increase in signal intensity in T2-weighted images (T2W) and in T1-weighted myocardial early gadolinium enhancement (MEGE), previously described CMR surrogates for myocardial fibrosis, myocardial edema and hyperemia, respectively., Methods: Fifty-four patients were analyzed. Sixteen patients with the indeterminate phase (IND), seventeen patients with the cardiac phase with no left ventricular systolic dysfunction (CPND), and twenty-one patients with the cardiac phase with left ventricular systolic dysfunction (CPD). All patients underwent 1.5 T CMR scan including LGE, T2W and MEGE image sequences to evaluate myocardial abnormalities., Results: Late gadolinium enhancement was present in 72.2 % of all patients, in 12.5 % of IND, 94.1 % of the CPND and 100 % of the CPD patients (p < 0.0001). Myocardial increase in signal intensity in T2-weighted images (T2W) was present in 77.8 % of all patients, in 31.3 % of the IND, 94.1 % of the CPND and 100 % of the CPD patients (p < 0.0001). T1-weighted myocardial early gadolinium enhancement (MEGE) was present in 73.8 % of all patients, in 25.0 % of the IND, 92.3 % of the CPND and 94.1 % of the CPD (p < 0.0001). A good correlation between LGE and T2W was observed (r = 0.72, and p < 0.001)., Conclusions: Increase in T2-weighted (T2W) myocardial signal intensity and T1-weighted myocardial early gadolinium enhancement (MEGE) can be detected by CMR in patients throughout all phases of Chagas' heart disease, including its subclinical presentation (IND). Moreover, those findings were parallel to myocardial fibrosis (LGE) in extent and location and also correlated with the degree of Chagas' heart disease clinical severity. These findings contribute to further the knowledge on pathophysiology of Chagas' heart disease, and might have therapeutic and prognostic usefulness in the future.

Background: Syndecan-4 is a transmembrane glycoprotein associated with inflammation and fibrosis. Increased syndecan-4 levels were previously detected after acute myocardial infarction and in subjects with heart failure. However, the levels of syndecan-4 in subjects with Chagas disease have not so far been investigated. The aim of this study was to investigate the potential role of serum sydencan-4 as a novel biomarker for myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. Methods: This study comprised subjects with Chagas disease (n = 56), being 14 (25%) with the indeterminate form, 16 (29%) with the cardiac form without ventricular dysfunction, and 26 (46%) with the cardiac form with ventricular dysfunction. Results: Syndecan-4 serum concentrations did not correlate with presence or absence of myocardial fibrosis (P = 0.386) nor disease severity in subjects with Chagas disease (P = 0.918). Additionally, no correlation was found either between the degree of myocardial fibrosis and serum syndecan-4 [r = 0.08; P = 0.567] or between left ventricular ejection fraction and syndecan-4 [r = 0.02; P = 0.864]. In contrast, NT-proBNP levels correlated with ejection fraction and myocardial fibrosis. Conclusions: Our results demonstrate the lack of correlations between serum syndecan-4, myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. Further studies are required to show if syndecan-4 concentrations can be marker for prognosis assessment or disease progression. [ABSTRACT FROM AUTHOR]

Background: Since a male-related higher cardiovascular morbidity and mortality in patients with Chagas' heart disease has been reported, we aimed to investigate gender differences in myocardial damage assessed by cardiovascular magnetic resonance (CMR). Methods and results: Retrospectively, 62 seropositive Chagas' heart disease patients referred to CMR (1.5 T) and with low probability of having significant coronary artery disease were included in this analysis. Amongst both sexes, there was a strong negative correlation between LV ejection fraction and myocardial fibrosis (male r = 0.64, female r = 0.73, both P < 0.001), with males showing significantly greater myocardial fibrosis (P = 0.002) and lower LV ejection fraction (P < 0.001) than females. After adjustment for potential confounders, gender remained associated with myocardial dysfunction, and 53% of the effect was mediated by myocardial fibrosis (for mediation P = 0.004). Also, the transmural pattern was more prevalent among male patients (23.7 vs. 9.9%, P < 0.001) as well as the myocardial heterogeneity or gray zone (2.2 vs. 1.3 g, P = 0.003). Conclusions: We observed gender-related differences in myocardial damage assessed by CMR in patients with Chagas' heart disease. As myocardial fibrosis and myocardial dysfunction are associated to cardiovascular outcomes, our findings might help to understand the poorer prognosis observed in males in Chagas' disease. [ABSTRACT FROM AUTHOR]

An abstract of the article "Detection of myocardial inflammation in Chagas' disease by cardiac magnetic resonance," by Evandro Naia and colleagues is presented.