natriuretic-peptide--brain and Chagas-Disease

Background Chagas disease (CD) presents an ominous prognosis. The predictive value of biomarkers and new echocardiogram parameters in adjusted models have not been well studied. Methods and Results There were 361 patients with chronic CD (57.6% men, 61±11 years of age, clinical forms: indeterminate 27.1%, cardiac 56.6%, digestive 3.6%, cardiodigestive 12.7%) included in this single-center, observational, prospective longitudinal study. Echocardiographic evaluation included strain analyses of left atrial, left ventricular (LV), and right ventricular and 3-dimensional analyses of left atrial and LV volumes. Biomarkers included cardiac troponin I, brain natriuretic peptide, transforming growth factor β1, tumor necrosis factor, matrix metalloproteinases, and

Topics: Atrial Fibrillation; Biomarkers; Chagas Disease; Echocardiography; Female; Humans; Longitudinal Studies; Male; Natriuretic Peptide, Brain; Prognosis; Prospective Studies; Stroke Volume; Ventricular Function, Left

To analyze the association of circulating dehydroepiandrosterone sulfate (DHEA-S) levels with cardiovascular outcomes in patients with chronic Chagas cardiomyopathy (CCM) diagnosis.. DHEA-S is among the main endogenous steroid hormones. Some studies have suggested a relevant role of this hormone in infections and the setting of CCM. Nevertheless, no study has evaluated the prognostic role of DHEA-S in CCM patients.. Prospective cohort study. Patients with CCM and reduced ejection fraction were included. We explored the association of DHEA-S levels with NT-proBNP levels and echocardiographic variables using linear regression models. Next, by using Cox Proportional Hazard models, we examined whether levels of DHEA-S could predict a composite outcome (CO) including all-cause mortality, cardiac transplantation, and implantation of a left ventricular assist device (LVAD).. Seventy-four patients were included (59% males, median age: 64 years). After adjustment for confounding factors, high DHEA-S levels were associated with better LVEF, lower left atrium volume, end-systolic volume of the left ventricle and lower NT-proBNP levels. 43% of patients experienced the CO during a median follow-up of 40 months. Increased levels of DHEA-S were associated with a lower risk of developing the CO (HR 0.43; 95%CI 0.21-0.86). Finally, adding DHEA-S to the multivariate model did not improve the prediction of the CO, but substituting NT-proBNP in the model with DHEA-S showed similar performance.. In patients with CCM, higher DHEA-S levels were associated with lower mortality, heart transplantation, and LVAD implantation. Further larger studies are required to confirm our results and assess causality.

Topics: Biomarkers; Cardiomyopathies; Chagas Cardiomyopathy; Chagas Disease; Dehydroepiandrosterone; Female; Heart Failure; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Peptide Fragments; Prognosis; Prospective Studies; Stroke Volume

This study aimed to assess the prevalence of non-use of health services in the last year by people with Chagas disease (CD) in an endemic area in Brazil and the contextual and individual factors associated with this non-use. This is a multilevel study that considered contextual and individual data. Contextual data were collected from official publicly accessible databases of the Brazilian government, at the municipal level. The individual data came from the first follow-up of a Brazilian cohort that assessed patients with CD in 21 municipalities in endemic area for the disease. The sample consisted of 1,160 individuals with CD. The dependent variable "use of health services in the last year" was categorized as yes vs. no. The analysis was performed using Poisson regression with robust variance. The prevalence of non-use of health services in the last year was 23.5% (IC95%: 21.1-25.9). The contextual factor "larger population" (PR: 1.6; 95% CI = 1.2-2.0) and individual factors related to the lower severity of the disease as a functional class without limitations (PR: 1.6; 95% CI = 1.2-2.1) and unaltered N-terminal pro b-type natriuretic peptide levels (PR: 2.2; 95% CI = 1.3-3.6) increased the prevalence of non-use of the health service in the last year by people with CD. The results of this study showed that individual determinants are not isolated protagonists of the non-use of health services in the last year by people with CD, which reinforces the need for public policies that consider the contextual determinants of the use of health services by populations affected by the disease.

Topics: Brazil; Chagas Disease; Cross-Sectional Studies; Health Services; Humans; Multilevel Analysis; Natriuretic Peptide, Brain; Socioeconomic Factors

Chagas disease (ChD) and systemic arterial hypertension (SAH) are two severe comorbidities that lead to mortality and a reduction in people's quality of life, with an impact on public health. The aim of this study was to quantify the biomarkers of cardiac injury in patients with ChD and SAH. Eighty patients were divided into four groups: 20 hypertensive patients, 20 ChD-hypertensive patients, 20 ChD patients, and 20 normotensive volunteers; all of them came from outpatient's public health services. Among the evaluated markers for cardiac lesions (creatine kinase, creatine kinase-MB isoform, myoglobin, high-sensitive cardiac troponin T[hs-cTnT], B-type natriuretic peptide [BNP], and C-reactive protein), hs-cTnT and BNP were the most appropriate. Importantly, our results showed that the cut off point for hs-cTnT could be < 0.007 ng/mL, which could lead to the early detection of myocardial lesions. The BNP and hs-cTnT levels were high only in the ChD and ChD-hypertensive patient groups, suggesting that Chagas' disease may play an important role in the increase of these biomarkers. ChD patients, hypertensive or not, with cardiac or cardiodigestive involvement presented significantly higher values of hs-cTnT (p < 0.001) and BNP (p = 0.001) than ChD patients with indeterminate and digestive forms, which strengthens the validation of these markers for the follow-up of clinical cardiac form of ChD. This study suggests that the BNP and hs-cTnT can be used as possible indirect biomarkers of cardiac damage. In addition, the reference values of these biomarkers in Chagas and hypertensive cardiomyopathies should be better understood with further studies.

Topics: Adult; Aged; Biomarkers; Chagas Disease; Female; Humans; Hypertension; Male; Middle Aged; Natriuretic Peptide, Brain; Predictive Value of Tests; Quality of Life; ROC Curve; Troponin T

Transforming growth factor β1 (TGF-β1) and tumour necrosis factor (TNF) have been implicated in Chagas disease pathophysiology and may correlate with left ventricular (LV) function.. We determined whether TGF-β1 and TNF serum levels correlate with LV systolic and diastolic functions and brain natriuretic peptide (BNP) serum levels in chronic Chagas disease.. This cross-sectional study included 152 patients with Chagas disease (43% men; 57 ± 12 years old), classified as 53 patients with indeterminate form and 99 patients with cardiac form (stage A: 24, stage B: 25, stage C: 44, stage D: 6). TGF-β1, TNF, and BNP were determined by enzyme-linked immunosorbent assay ELISA. Echocardiogram was used to determine left atrial and LV diameters, as well as LV ejection fraction and diastolic function.. TGF-b1 serum levels were lower in stages B, C, and D, while TNF serum levels were higher in stages C and D of the cardiac form. TGF-β1 presented a weak correlation with LV diastolic function and LV ejection fraction. TNF presented a weak correlation with left atrial and LV diameters and LV ejection fraction.. TNF is increased, while TGF-β1 is decreased in the cardiac form of chronic Chagas disease. TNF and TGF-β1 serum levels present a weak correlation with LV systolic and diastolic function in Chagas disease patients.

Topics: Adult; Aged; Case-Control Studies; Chagas Disease; Cross-Sectional Studies; Diastole; Echocardiography; Electrocardiography; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Reference Values; Severity of Illness Index; Statistics, Nonparametric; Systole; Transforming Growth Factor beta1; Tumor Necrosis Factors; Ventricular Function, Left

To evaluate the correlation of the total distance walked during the six-minute walk test (6MWT) with left ventricular function and quality of life in patients with Chagas Disease (ChD) complicated by heart failure.. This is a cross-sectional study of adult patients with ChD and heart failure diagnosed based on Framingham criteria. 6MWT was performed following international guidelines. New York Heart Association functional class, brain natriuretic peptide (BNP) serum levels, echocardiographic parameters and quality of life (SF-36 and MLHFQ questionnaires) were determined and their correlation with the distance covered at the 6MWT was tested.. Forty adult patients (19 male; 60 ± 12 years old) with ChD and heart failure were included in this study. The mean left ventricular ejection fraction was 35 ± 12%. Only two patients (5%) ceased walking before 6 min had elapsed. There were no cardiac events during the test. The average distance covered was 337 ± 105 metres. The distance covered presented a negative correlation with BNP (r = -0.37; P = 0.02), MLHFQ quality-of-life score (r = -0.54; P = 0.002), pulmonary artery systolic pressure (r = -0.42; P = 0.02) and the degree of diastolic dysfunction (r = -0.36; P = 0.03) and mitral regurgitation (r = -0.53; P = 0.0006) and positive correlation with several domains of the SF-36 questionnaire.. The distance walked during the 6MWT correlates with BNP, quality of life and parameters of left ventricular diastolic function in ChD patients with heart failure. We propose this test to be adopted in endemic areas with limited resources to aid in the identification of patients who need referral for tertiary centres for further evaluation and treatment.

Topics: Chagas Disease; Cross-Sectional Studies; Echocardiography; Female; Heart Failure; Humans; Immunoenzyme Techniques; Male; Middle Aged; Natriuretic Peptide, Brain; Quality of Life; Ventricular Function, Left; Walk Test

Topics: Adult; Aged; Biomarkers; Brazil; Chagas Disease; Female; Follow-Up Studies; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Pacemaker, Artificial; Population Surveillance; Prevalence; Treatment Outcome; Ventricular Function, Left

To identify predictors of low cardiac output and mortality in decompensated heart failure.. Introduction: Patients with decompensated heart failure have a high mortality rate, especially those patients with low cardiac output. However, this clinical presentation is uncommon, and its management is controversial.. We studied a cohort of 452 patients hospitalized with decompensated heart failure with an ejection fraction of <0.45. Patients underwent clinical-hemodynamic assessment and Chagas disease immunoenzymatic assay. Low cardiac output was defined according to L and C clinical-hemodynamic profiles. Multivariate analyses assessed clinical outcomes. P<0.05 was considered significant.. The mean age was 60.1 years; 245 (54.2%) patients were >60 years, and 64.6% were men. Low cardiac output was present in 281 (63%) patients on admission. Chagas disease was the cause of heart failure in 92 (20.4%) patients who had higher B type natriuretic peptide levels (1,978.38 vs. 1,697.64 pg/mL; P = 0.015). Predictors of low cardiac output were Chagas disease (RR: 3.655, P<0.001), lower ejection fraction (RR: 2.414, P<0.001), hyponatremia (RR: 1.618, P = 0.036), and renal dysfunction (RR: 1.916, P = 0.007). Elderly patients were inversely associated with low cardiac output (RR: 0.436, P = 0.001). Predictors of mortality were Chagas disease (RR: 2.286, P<0.001), ischemic etiology (RR: 1.449, P = 0.035), and low cardiac output (RR: 1.419, P = 0.047).. In severe decompensated heart failure, predictors of low cardiac output are Chagas disease, lower ejection fraction, hyponatremia, and renal dysfunction. Additionally, Chagas disease patients have higher B type natriuretic peptide levels and a worse prognosis independent of lower ejection fraction.

Topics: Cardiac Output, Low; Chagas Disease; Epidemiologic Methods; Female; Heart Failure; Humans; Hyponatremia; Kidney Diseases; Male; Middle Aged; Natriuretic Peptide, Brain; Reference Values; Risk Factors; Stroke Volume

Long-term right ventricular apical pacing can cause ventricular dyssynchrony and, secondarily, neurohumoral alterations and increase in cardiac morbimortality.. To analyze ventricular dyssynchrony and its effects on BNP levels in patients with pacemakers and long-term right ventricular (RV) apex pacing.. Cross-sectional study of 85 patients with single or dual chamber pacemaker, NYHA functional class I or II and left ventricular ejection fraction (LVEF) ≥ 35%. The dyssynchrony assessment was carried out using several echocardiographic techniques, including Tissue Synchronization Imaging (TSI), with the analysis of the 12 segments. BNP was measured at the same time when the echocardiogram was performed, but the examiner was blinded to the results.. Forty-six women and 39 men, aged 58 ± 12 years, with Chagas' disease (56%) and controlled hypertensive individuals (62%), were included in the study. LVEF was 52 ± 8% and the mean QRS duration was 139 ms (120-180 ms). BNP levels were altered in 36.5% of the sample (cutoff = 60 pg/ml). At the multivariate linear regression analysis, BNP was correlated with age (p = 0.024), LVEF (p < 0.0001) and left ventricular (LV) pre-ejection time (p = 0.009), which is an intraventricular dyssynchrony index.. In clinically stable patients receiving conventional cardiac pacing, the intraventricular dyssynchrony was an independent predictor of BNP level increase after adjusted for age and LVEF.

Topics: Adult; Aged; Cardiac Pacing, Artificial; Chagas Disease; Epidemiologic Methods; Female; Humans; Hypertension; Male; Middle Aged; Natriuretic Peptide, Brain; Stroke Volume; Ultrasonography; Ventricular Dysfunction, Left; Ventricular Function, Right; Young Adult

Topics: Cardiac Output, Low; Chagas Disease; Female; Heart Failure; Humans; Male; Natriuretic Peptide, Brain; Stroke Volume

B-type natriuretic peptide (BNP) is a diagnostic and prognostic tool in heart failure and also in Chagas disease, which is caused by the protozoan Trypanosoma cruzi and has cardiomyopathy as a main feature. BNP lipolytic actions and T. cruzi infection in the adipose tissue have been recently described. We aim to investigate the relationship between BNP and anthropometric measures and whether it is influenced by T. cruzi infection. We measured BNP, body mass index (BMI), waist circumference (WC), triceps skin-fold thickness (TSF) and performed serological, biochemical and electrocardiographic exams in 1398 subjects (37.5% infected with T. cruzi) in a community-dwelling elderly population in Bambui city, Brazil. Linear multivariate regression analysis was performed to investigate determinants of BNP levels. BNP levels were significantly (p<0.05) higher in T. cruzi-infected subjects than in the non-infected group (median=121 and 64pg/mL, respectively). BMI, WC and TSF in infected subjects were significantly lower than those in non-infected subjects (24.3 vs. 25.5kg/m2; 89.2 vs. 92.4cm; and 14.5 vs. 16.0mm, respectively). There was an inverse relationship between BNP levels and BMI (b=-0.018), WC (b=-0.005) and TSF (b=-0.193) levels. Infected and non-infected groups showed similar inverse relationships between BNP and BMI (b=-0.021 and b=-0.015, respectively). In conclusion, there was an inverse relationship between BNP levels and the anthropometric measures. Despite the actions in the adipose tissue, T. cruzi infection did not modify the associations between BNP and BMI, suggesting that body mass does not modify the accuracy of BNP in Chagas disease.

Topics: Aged; Biomarkers; Blood Pressure; Body Mass Index; Brazil; Chagas Cardiomyopathy; Chagas Disease; Cohort Studies; Creatine; Cross-Sectional Studies; Female; Humans; Linear Models; Male; Middle Aged; Natriuretic Peptide, Brain; Prevalence; Skinfold Thickness; Trypanosoma cruzi; Waist Circumference

Angiotensin-converting enzyme (ACE) 2 is a novel homologue of ACE. It metabolizes angiotensin (Ang)II to Ang-(1-7). This study aims to investigate the diagnostic and prognostic potency of circulating ACE2 activity in patients with heart failure (HF) from Chagas' disease (CD).. Blood samples were obtained from 111 CD patients and 40 age- and gender-matched healthy subjects. The CD patients were further subdivided according to their New York Heart Association classification. ACE2 activity was significantly increased in CD patients with HF, but not in patients without systolic dysfunction. Moreover, plasma ACE2 activity was significantly correlated with their clinical severity and echocardiographic parameters. Importantly, the potency of circulating ACE2 activity in CD patients was equally potent as that of B-type natriuretic peptide to predict cardiac death and heart transplant. Most importantly, patients with both parameters elevated were on a 5-fold higher risk to reach an endpoint than patients with increase in only 1 of the 2 parameters.. Determination of ACE2 activity may provide a new and important diagnostic and prognostic marker for patients with CD. ACE2 activity and BNP concentration have additive predictive value and may be used in combination to offer a new dimension of prediction in HF.

Topics: Angiotensin-Converting Enzyme 2; Biomarkers; Chagas Disease; Cohort Studies; Enzyme Activation; Female; Follow-Up Studies; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Peptidyl-Dipeptidase A; Predictive Value of Tests; Prognosis; Prospective Studies

In this study, the authors aimed to investigate the prognostic value of brain-type natriuretic peptide (BNP) for all-cause mortality among persons with Chagas disease, a parasitic disease caused by the protozoan Trypanosoma cruzi. The authors used data on 1,398 participants (37.5% infected with T. cruzi) aged 60 years and over from the Bambuí Cohort Study of Aging in Brazil. From 1997 to 2007, 512 participants died, leading to 12,406 person-years of observation. The hazard ratio for death was 1.27 for each unit of log-transformed BNP level (95% confidence interval (CI: 1.11, 1.45) among infected persons, independent of potentially confounding factors. Infected persons with baseline BNP levels in the top quartile had a risk of death twice that of persons in the bottom quartile (hazard ratio = 2.07, 95% CI: 1.29, 3.32). The discriminatory ability of BNP in predicting mortality (C = 0.69, 95% CI: 0.66, 0.71) was similar to that of an electrocardiogram (C = 0.68, 95% CI: 0.65, 0.71), with reasonably stable risk discrimination over time. BNP is a strong predictor of mortality in older adults with Chagas disease. Although the usefulness of BNP for risk stratification in this parasitic disease remains a topic of debate, this study found that BNP-based risk discrimination is at least comparable to that of an electrocardiogram.

Topics: Aged; Aging; Antiprotozoal Agents; Biomarkers; Blood Pressure; Body Mass Index; Brazil; Chagas Disease; Cohort Studies; Diabetes Complications; Electrocardiography; Female; Follow-Up Studies; Humans; Indians, South American; Male; Middle Aged; Natriuretic Peptide, Brain; Predictive Value of Tests; Residence Characteristics; Smoking

Topics: Atrial Fibrillation; Biomedical Research; Chagas Cardiomyopathy; Chagas Disease; Humans; Incidence; Latin America; Natriuretic Peptide, Brain; Stroke; Survival Rate; Trypanosoma cruzi

Previous case-control studies have suggested a causal link between Chagas disease, which is caused by the protozoan Trypanosoma cruzi, and stroke. We investigated the relationship between Chagas disease and long-term stroke mortality in a large community-based cohort of older adults.. Participants were 1398 (80.3% from total) residents aged ≥ 60 years in Bambuí City, Brazil. The end point was death from stroke. Potential confounding variables included age, sex, conventional stroke risk factors, and high sensitive C-reactive protein.. Participants of this study were followed from 1997 to 2007 leading to 9740 person-years of observation. The baseline prevalence of T. cruzi infection was 37.5% and the overall mortality rate from stroke was 4.62 per 1000 person-years. The risk of death from stroke among T. cruzi-infected participants was twice that of those noninfected (adjusted hazard ratio, 2.36; 95% CI, 1.25 to 4.44). A B-type natriuretic peptide level in the top quartile was a strong and independent predictor of stroke mortality among those infected (adjusted hazard ratio, 2.72; 95% CI, 1.25 to 5.91). The presence of both a high B-type natriuretic peptide level and electrocardiographic atrial fibrillation increased the risk of stroke mortality by 11.49 (95% CI, 3.19 to 41.38) in these individuals.. This study provides new evidence supporting a causal link between Chagas disease and stroke. The results also showed that B-type natriuretic peptide alone or in association with atrial fibrillation has prognostic value for stroke mortality in T. cruzi chronically infected older adults.

Topics: Aged; Aged, 80 and over; Atrial Fibrillation; Brazil; C-Reactive Protein; Chagas Disease; Cohort Studies; Female; Humans; Incidence; Male; Middle Aged; Natriuretic Peptide, Brain; Predictive Value of Tests; Prognosis; Retrospective Studies; Risk Factors; Stroke; Survival Rate; Trypanosoma cruzi

We identified IgG reactive with human cardiac troponin-I (cTnI) in plasma and serum samples (N = 1930) from normal blood donors, and in sample cohorts characterized on the basis of clinical biomarkers associated with cardiac, infectious, and autoimmune diseases. cTnI and brain natriuretic peptide were the biomarkers chosen to reflect myocyte damage or left ventricular dysfunction, respectively. The infectious disease cohorts were serologically positive for antibodies to hepatitis B (natural infection), hepatitis C virus, and Chagas (i.e., T.cruzi). The autoimmune cohorts were represented by samples from diagnosed systemic lupus erythematosus (biomarker: dsDNA) and rheumatoid arthritis (biomarker: rheumatoid factor) subjects. The prevalence of IgG autoantibodies reactive with cTnI was high in the normal donor cohort (95/750, 12.7%). The prevalence in the other sample cohorts was not significantly different from that in the normal blood donors, with the exception of a slight increase in the rheumatoid factor cohort (28/137, 20.4%). The presence of anti-cTnI IgG in highly reactive samples was confirmed by inhibition with the antigen and further by screening with a library of peptides derived from the human cTnI amino acid sequence. Our data suggest that these autoantibodies are polyspecific, encompassing epitopes across the entire cTnI sequence, including the cardiac-specific amino terminal region.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Amino Acid Sequence; Antibodies, Viral; Arthritis, Rheumatoid; Autoantibodies; Chagas Disease; Child; Cohort Studies; Female; Hepatitis B; Hepatitis C; Humans; Immunoglobulin G; Luminescent Measurements; Lupus Erythematosus, Systemic; Male; Middle Aged; Natriuretic Peptide, Brain; Reproducibility of Results; Troponin I; Young Adult

Chagas' disease (CD) affects around 18 million people in Latin America. To determine the diagnostic and prognostic value of natriuretic peptides in patients with CD, we measured atrial (ANP) and brain natriuretic peptide (BNP), and compared the findings with other dilated cardiomyopathies (DCM).. Blood samples were obtained from 111 CD patients, 62 patients with DCM due to other causes, and 43 gender- and age-matched healthy subjects. The CD and DCM patients were subdivided according to their NYHA classification. Natriuretic peptide concentrations were determined by immunoradiometric assays.. ANP and more pronounced BNP levels were increased in CD and DCM patients in relation to the NYHA class. Circulating BNP concentrations were higher in CD patients in NYHA classes I-II than in the corresponding DCM patients (p = 0.020). Importantly, ANP and BNP were already significantly elevated in CD patients without systolic ventricular dysfunction (p < or = 0.001). In CD patients, both peptides were highly correlated with echocardiographic parameters (p < 10(-14)). Both ANP and BNP had comparable ability to predict death or the necessity for heart transplant (p < 0.0001).. Natriuretic peptide levels can be used as a marker of asymptomatic CD without ventricular dysfunction and thus could be an ideal tool to identify these patients for early therapy.

Topics: Adult; Atrial Natriuretic Factor; Biomarkers; Blood Pressure; Case-Control Studies; Chagas Disease; Echocardiography; Female; Follow-Up Studies; Heart Failure; Heart Transplantation; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Natriuretic Peptide, Brain; Prognosis; Proportional Hazards Models; ROC Curve; Stroke Volume

NT-proBNP levels are known to be elevated in systolic and diastolic dysfunction. Doppler indices of diastolic dysfunction (DD) have been shown to have prognostic value in patients with Chagas' cardiomyopathy (CC). However, the additional value of NT-proBNP levels in further stratifying these patients according to DD has not been established. This study analyzed the correlation of N-terminal proBNP (NT-proBNP) levels with systolic and diastolic function in patients with CC.. NT-proBNP levels were measured in 59 patients with dilated cardiomyopathy due to Chagas disease without other systemic illness that were studied by Doppler echocardiography, including left atrial volume (LAV) calculation and tissue Doppler evaluation of LV longitudinal function. Univariate analysis showed a strong correlation of NT-proBNP values with LVEF (r=-0.733, p<0.001) and a weak correlation with most Doppler echocardiographic parameters of diastolic function. On a multivariate analysis, LVEF and LAV volume emerged as correlating with elevated levels of the NT-proBNP. Patients with restrictive filling pattern (n=10), when compared to other patterns of DD, (n=49), showed a lower LVEF (25.4+/-6.4% vs. 39.8+/-9.4, p<0.001), a larger LAV (50.1+/-17.2 vs. 37.7+/-15.6 ml/m(2), p=0.004) and higher NT-proBNP levels (median+/-IQR: 3488+/-3056 vs. 492+/-700 pg/dl, p<0.001). A marked elevated concentration of NT-proBNP (> or =800 pg/ml) had a sensitivity of 90.0%, specificity of 70.5%, positive predictive value of 40.9% and negative predictive value of 96.9% for detecting a restrictive filling pattern.. In patients with CC, NT-proBNP augmentation is a marker of LV dysfunction, with higher levels correlating with the more severe forms of both systolic and diastolic dysfunction.

Topics: Adult; Aged; Biomarkers; Cardiomyopathy, Dilated; Chagas Disease; Diastole; Female; Heart Failure; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Peptide Fragments; Prospective Studies; Stroke Volume; Systole; Time Factors; Ultrasonography; Ventricular Dysfunction, Left

Leptin is produced primarily by adipocytes. Although originally associated with the central regulation of satiety and energy metabolism, increasing evidence indicates that leptin may be an important mediator in cardiovascular pathophysiology. The aim of the present study was to investigate plasma leptin levels in patient with Chagas' heart disease and their relation to different forms of the disease. We studied 52 chagasic patients and 30 controls matched for age and body mass index. All subjects underwent anthropometric, leptin and N-terminal pro-brain natriuretic peptide (NT-proBNP) measurements and were evaluated by echocardiography, 12-lead electrocardiogram (ECG), and chest X-ray. All patients had fasting blood samples taken between 8:00 and 9:00 am. Chagasic patients were divided into 3 groups: group I (indeterminate form, IF group) consisted of 24 subjects with 2 positive serologic reactions for Chagas' disease and no cardiac involvement as evaluated by chest X-rays, ECG and two-dimensional echocardiography; group II (showing ECG abnormalities and normal left ventricular systolic function, ECG group) consisted of 14 patients; group III consisted of 14 patients with congestive heart failure (CHF group) and left ventricular dysfunction. Serum leptin levels were significantly lower (P < 0.001) in the CHF group (1.4 +/- 0.8 ng/mL) when compared to the IF group (5.3 +/- 5.3 ng/mL), ECG group (9.7 +/- 10.7 ng/mL), and control group (8.1 +/- 7.8 ng/mL). NT-proBNP levels were significantly higher (P < 0.001) in the CHF group (831.8 +/- 800.1 pg/mL) when compared to the IF group (53.2 +/- 33.3 pg/mL), ECG group (83.3 +/- 57.4 pg/mL), and control group (32 +/- 22.7 pg/mL). Patients with Chagas' disease and an advanced stage of CHF have high levels of NT-ProBNP andlow plasma levels of leptin. One or more leptin-suppressing mechanisms may operate in chagasic patients.

Topics: Adult; Biomarkers; Body Mass Index; Case-Control Studies; Chagas Cardiomyopathy; Chagas Disease; Echocardiography; Electrocardiography; Female; Fluoroimmunoassay; Heart Failure; Humans; Leptin; Male; Middle Aged; Natriuretic Peptide, Brain; Peptide Fragments; Ventricular Dysfunction, Left

Left ventricular dysfunction (LVd) is the main predictor of mortality in Chagas disease (ChD).. To compare the diagnostic performance of the conventional approach (ECG and chest X-ray) in the recognition of LVd in ChD, with a new strategy, in which BNP is measured in patients with an abnormal ECG.. Consecutive ChD patients recruited at an Outpatient Reference Center in Belo Horizonte, Brazil, without other systemic diseases, in 1998-99 (sample 1, n = 165) and in 2001-02 (sample 2, n = 62) underwent ECG, chest X-ray, BNP measurement and echocardiography.. The prevalence of LVd (ejection fraction

Topics: Adult; Aged; Chagas Disease; Electrocardiography; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Predictive Value of Tests; Sensitivity and Specificity; Ventricular Dysfunction, Left

Chagas disease (ChD) patients might present chronotropic incompetence during exercise, although its physiopathology remains uncertain. We evaluated the heart rate (HR) response to exercise testing in ChD patients in order to determine the role of autonomic modulation and left ventricular dysfunction in the physiopathology of chronotropic incompetence.. ChD ambulatory patients (n = 170) and healthy controls (n = 24) underwent a standardized protocol including Doppler echocardiography, Holter monitoring, HR variability analysis, brain natriuretic peptide (BNP) measurement, and maximal exercise testing. The chronotropic response was calculated as the percentage of predicted HR achieved and the HR increment (DeltaHR) during exercise. ChD patients were divided according to the absence or presence of cardiopathy and chronotropic incompetence (<85% predicted HR).. Chronotropic incompetence was present in 34 (20%) of all ChD patients. The group with cardiopathy displayed reduced DeltaHR (91 +/- 19 bpm) during exercise in comparison with ChD patients without cardiopathy (100 +/- 19 bpm). Both the values observed in ChD groups were significantly different from those of controls (112 +/- 13 bpm). Exercise duration, maximal oxygen consumption, and systolic blood pressure increment were significantly reduced in patients with abnormal chronotropic response. DeltaHR during the exercise was significantly correlated with markers of autonomic control of sinus node, such as rest HR (r =-0.498, P

Topics: Adult; Aged; Analysis of Variance; Autonomic Nervous System; Case-Control Studies; Chagas Disease; Chi-Square Distribution; Echocardiography, Doppler; Electrocardiography, Ambulatory; Exercise Test; Female; Heart Rate; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Statistics, Nonparametric; Ventricular Dysfunction, Left

To evaluate asymptomatic patients with chronic Chagas disease to determine prevalence of ventricular arrhythmias, left ventricular dysfunction, and B-type natriuretic peptide (BNP) plasma levels.. One hundred and six patients from the Chagas disease outpatient clinic underwent clinical evaluation, electrocardiogram (ECG), cardiothoracic index (CTI), ambulatory electrocardiogram (Holter monitoring), echocardiogram, and BNP measurement and then were distributed into three groups: GI, with normal ECG (n = 50); GIIA, with ECG changes characteristic of Chagas disease (n = 31); and GIIB, with other ECG changes (n = 25).. The most common electrocardiographic changes were the following. GIIA: complete right bundle branch block (35%), left anterior hemiblock (35%), and electrically inactive areas (32%); GIIB: inferolateral repolarization change (28%), and left ventricular overload (24%). Mean CTI index values were similar (p = 0.383). Ventricular arrhythmia prevalence was higher in the GIIA (77%) and GIIB (75%) groups than in the GI group (46%) (p = 0.002). Ventricular dysfunction was more prevalent in the GIIA (52%) and GIIB (32%) groups than in the GI group (14%) (p = 0.001). Systolic dysfunction was more prevalent in the GIIA group (29%) than in the GIIB (20%) and GI groups (2%) (p < 0.001). Diastolic dysfunction was more prevalent in the GIIA (42%) and GIIB (28%) groups than in the GI group (12%) (p = 0.005). Mean B-type natriuretic peptide levels were 30 +/- 88 pg/mL in the GI group, 66 +/- 194 in the GIIA group and 24 +/- 82 for the GIIB group (p = 0.121), respectively.. Arrhythmias and left ventricular dysfunction are more prevalent in asymptomatic patients with chronic Chagas disease and abnormal ECG than in patients with normal ECG. Plasma BNP levels were similar among the groups.

Topics: Adult; Arrhythmias, Cardiac; Biomarkers; Chagas Cardiomyopathy; Chagas Disease; Chronic Disease; Cross-Sectional Studies; Echocardiography; Electrocardiography; Female; Humans; Male; Natriuretic Peptide, Brain; Prevalence; Prospective Studies; Sensitivity and Specificity; Ventricular Dysfunction, Left

To measure the serum levels of brain natriuretic peptide (BNP) in patients with chronic chagasic heart disease and in individuals with positive serology for Chagas' disease and no heart impairment, and to correlate the serum BNP levels with the degree of cardiac impairment, cardiac dimensions, presence of a pacemaker, and ejection fraction.. Serum BNP concentrations were determined by use of the Triage-BNP Test produced by BIOSITE. Serum BNP was assessed in 25 patients from the Chagas' disease outpatient clinic of the Hospital Universitario Oswaldo Cruz, who were divided into 2 groups as follows: 1) G1--comprising 13 asymptomatic patients with positive serology for Chagas' disease and no heart disease detectable on electrocardiography, chest X-ray, and echocardiography; and 2) G2--comprising 12 patients with Chagas' disease and heart impairment.. Significantly more elevated BNP levels were detected in the chagasic patients with cardiac impairment: (G1=4.4 +/-4.4 pg/ml, G2=293.0+/-460.2 pg/ml); (P<0.01). In the 2 groups, the serum levels of BNP correlated neither with age nor with sex. The levels were directly proportional to functional class and cardiac area on chest X-ray. Although a trend towards an increment in systolic function impairment was observed, no linear correlation with the ejection fraction on echocardiography occurred. The presence of definitive pacemaker and electrocardiographic alterations did not change the serum BNP levels.. Asymptomatic individuals with a positive serology for Chagas' disease and no evidence of ventricular dysfunction have serum BNP levels similar to those of the general population.

Topics: Adult; Aged; Biomarkers; Chagas Cardiomyopathy; Chagas Disease; Echocardiography; Electrocardiography; Female; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Severity of Illness Index

Topics: Biomarkers; Chagas Disease; Comorbidity; Humans; Natriuretic Peptide, Brain; Ventricular Dysfunction, Left

Left ventricular dysfunction in Chagas' disease is common but can be difficult to detect. We investigated whether measurement of plasma brain natriuretic peptide (BNP) could identify patients with left ventricular dysfunction who need further investigation or treatment. Among patients with an abnormal electrocardiogram or chest radiograph, a BNP concentration of 60.7 pmol/L or higher has a sensitivity and positive predictive value of 80%, and specificity and negative predictive value of 97%. Measurement of plasma BNP concentration could be a useful method to screen patients with Chagas' disease.

Topics: Adult; Biomarkers; Chagas Disease; Female; Humans; Male; Natriuretic Peptide, Brain; Sensitivity and Specificity; Ventricular Dysfunction, Left