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Background Chagas disease (ChD) has a long asymptomatic period, where there is no evidence of myocardial damage. However, incipient alterations in ventricular systo-diastolic function have been described using echocardiography with Tissue Doppler and Strain. On the other hand, the presence of elevated higth-sensitivity T troponin (HS-TnT) and N-terminal pro B-type natriuretic peptide (NT-pro BNP) has been documented in the early stages of the ChD. The association between the elevation of both markers and incipient alterations in ventricular function in patients with ChD without evidence of heart damage has been poorly studied. Purpose The aim of this study is to evaluate the prevalence of elevation of both biomarkers (HS-TnT and NT-proBNP) and their association with insipients alterations in systo-diastolic function in patients with ChD without evidence of structural heart affection. Materials and methods Outpatients with stage 0 of ChD (positive serology, with normal electrocardiogram, holter and chest teleradiography) were included prospectively. They were divided in three groups according to the dosage of HS-TnT and NT-proBNP. Group 1: patients with both markers within normal values; group 2: patients with elevation of one of the markers (HS-TnT>13 ng/L OR NT-proBNP>125 pg/ml) and group 3: patients with elevation of both markers (HS-TnT>13 ng/L AND NT-proBNP>125 pg/ml). All of them underwent Doppler echocardiography with tissue Doppler. Results Two hundred and sixty-one patients were included, with 47±9 years old of age, 44% woman, 86.6% (n=226) in group 1, 9.6% (n=25) in group 2 and 3.8% (n=10) in group 3. Table 1 shows the main results. Conclusions Elevation of both markers was found in almost 4% of patients. This elevation was associated with a higher E/e' ratio, E/A ratio, Letf Atrial Area and a lower S'-wave lateral. Funding Acknowledgement Type of funding source: None

Background Several studies have shown autonomic dysfunction in early stages of Chagas disease (ChD). These alterations may be involved in the progression of the disease. The Valsalva Ratio (VR) is one of the most used tests to evaluate parasympathetic function, because it is easy and reproducible. On the other hand, the Higth Sensitive T troponin (HS-TnT) and the N-terminal pro B-type natriuretic peptide (NT-proBNP) are specific markers of myocardial damage and elevation of filling pressures, respectively. Both elevations are asociated with higher risk. The association between autonomic dysfunction and biomarker levels in ChD without evidence of structural heart affection, has been poorly studied. Purpose The aim of this study is to evaluate the presence of abnormal VR as an expression of disanutonomy in patients with Chagas without evidence of structural heart disease and its association with HS-TnT and NT-proBNP levels. Methods A prospective study was performed, which included outpatients with positive serology for Chagas, with electrocardiogram, ergometry, holter and Doppler echocardiogram within normal parameters. The exclusion criteria were the following: history of ischemic heart disease, neurological diseases, chronic renal failure (clearence <30 ml/min), arterial hypertension and diabetes mellitus. All patients underwent a valsalva maneuver (VM), with continuous recording of the R-R interval by electrocardiogram. The VR was calculated dividing the longest RR interval after VM over the shortest RR interval during VM. Abnormal VR was considerated as a value <1.1. In addition, HS-TnT and NT-proBNP were measured in all patients. Results One hundred and forty four patients were included, with 45±8 years old, 44% fameles. The VR was 1.22±0.12, HS-TnT 6.44±3.8 ng/L and the NT-proBNP was 55±44 pg/ml. Abnormal VR was found in 29.1% of patients (n=42). The abnormal VR group showed a higher level of HS-TnT (8.11±3.8 versus 5.7±3.5 ng/L, p=0.0006) and higher level of NT-proBNP (78±54 versus 45±36 pg/ml, p<0.0001). In addition, the abnormal VR group presented a greater E/e'ratio (9.48±2.5 versus 7.1±1.8, p<0.0001) and greater s wave (0.08±0.02 versus 0.10±0.02 cm/sec, p=0.02). In the multivariate análisis, abnormal VR was asociated with higher HS-TnT (OR 1.22 (CI 95% 1.04–1.43), p=0.01) and higher E/e'ratio (OR 1.54 (CI95% 1.17–2.02), p=0.001), but not with NT-proBNP (p=0,09). Conclusions About one third of patients with ChD without evidence of cardiopaty had autonomic dysfunction. The patients with abnormal VR had higher leves of HS-TnT and NT-proBNP, but in the multivariate analisys only the HS-TnT had associated with abnormal VR.