The Burden of Chagas Disease in the Contemporary World: The RAISE Study

Chagas disease (ChD), a Neglected Tropical Disease, has witnessed a transformative epidemiological landscape characterized by a trend of reduction in prevalence, shifting modes of transmission, urbanization, and globalization. Historically a vector-borne disease in rural areas of Latin America, effective control measures have reduced the incidence in many countries, leading to a demographic shift where most affected individuals are now adults. However, challenges persist in regions like the Gran Chaco, and emerging oral transmission in the Amazon basin adds complexity. Urbanization and migration from rural to urban areas and to non-endemic countries, especially in Europe and the US, have redefined the disease's reach. These changing patterns contribute to uncertainties in estimating ChD prevalence, exacerbated by the lack of recent data, scarcity of surveys, and reliance on outdated models. Besides, ChD's lifelong natural history, marked by acute and chronic phases, introduces complexities in diagnosis, particularly in non-endemic regions where healthcare provider awareness is low. The temporal dissociation of infection and clinical manifestations, coupled with underreporting, has rendered ChD invisible in health statistics. Deaths attributed to ChD cardiomyopathy often go unrecognized, camouflaged under alternative causes. Understanding these challenges, the RAISE project aims to reassess the burden of ChD and ChD cardiomyopathy. The project is a collaborative effort of the World Heart Federation, Novartis Global Health, the University of Washington's Institute for Health Metrics and Evaluation, and a team of specialists coordinated by Brazil's Federal University of Minas Gerais. Employing a multidimensional strategy, the project seeks to refine estimates of ChD-related deaths, conduct systematic reviews on seroprevalence and prevalence of clinical forms, enhance existing modeling frameworks, and calculate the global economic burden, considering healthcare expenditures and service access. The RAISE project aspires to bridge knowledge gaps, raise awareness, and inform evidence-based health policies and research initiatives, positioning ChD prominently on the global health agenda.

Chagas cardiomyopathy in Boston, Massachusetts: Identifying disease and improving management after community and hospital-based screening

BACKGROUND

Limited data exist regarding cardiac manifestations of Chagas disease in migrants living in non-endemic regions.

METHODS

A retrospective cohort analysis of 109 patients with Chagas disease seen at Boston Medical Center (BMC) between January 2016 and January 2023 was performed. Patients were identified by screening and testing migrants from endemic regions at a community health center and BMC. Demographic, laboratory, and cardiac evaluation data were collected.

RESULTS

Mean age of the 109 patients was 43 years (range 19-76); 61% were female. 79% (86/109) were diagnosed with Chagas disease via screening and 21% (23/109) were tested given symptoms or electrocardiogram abnormalities. Common symptoms included palpitations (25%, 27/109) and chest pain (17%, 18/109); 52% (57/109) were asymptomatic. Right bundle branch block (19%, 19/102), T-wave changes (18%, 18/102), and left anterior fascicular block (11%, 11/102) were the most common electrocardiogram abnormalities; 51% (52/102) had normal electrocardiograms. Cardiomyopathy stage was ascertained in 94 of 109 patients: 51% (48/94) were indeterminate stage A and 49% (46/94) had cardiac structural disease (stages B1-D). Clinical findings that required clinical intervention or change in management were found in 23% (25/109), and included cardiomyopathy, apical hypokinesis/aneurysm, stroke, atrial or ventricular arrhythmias, and apical thrombus.

CONCLUSIONS

These data show high rates of cardiac complications in a cohort of migrants living with Chagas disease in a non-endemic setting. We demonstrate that Chagas disease diagnosis prompts cardiac evaluation which often identifies actionable cardiac disease and provides opportunities for prevention and treatment.

Characterization of Patients With Heart Failure of Chagas Etiology in Colombia: An Analysis Based on the Colombian Registry of Heart Failure (RECOLFACA)

Chronic Chagas cardiomyopathy (CCM) represents a relevant origin of Heart Failure (HF) in countries where the disease is endemic. CCM exhibits distinct myocardial involvement and is associated with a poorer prognosis compared to different HF etiologies. The aim is to explain the features and prognosis of individuals with HF resultant to CCM registered in the Colombian Registry of Heart Failure (RECOLFACA). RECOLFACA registry enrolled 2528 adult patients with HF. A comparison was made between patients diagnosed with CCM and those diagnosed with other etiologies of HF. Eighty-eight patients (3.5%) present CCM diagnosis. The individuals diagnosed with both HF and CCM were notably younger in age, had less comorbidities, poorer functional class, and significantly inferior ejection fraction. Finally, the presence of CCM diagnosis was linked to a substantially elevated mortality risk throughout the follow-up period (HR 2.01; 95% CI, 1.01-4.00) according to a multivariate model adjusted. CCM represents an important etiology of HF in Colombia, drawing attention to a distinct clinical profile and a higher risk of mortality compared to other HF etiologies.

Chronic Chagas Cardiomyopathy in the Brazilian Amazon region: clinical characteristics and regional distinctiveness

Objectives

This study aims to provide a comprehensive analysis of clinical and epidemiological data related to Chronic Chagas Cardiomyopathy (CCC) in the Amazon region of Brazil.

Methods

A review of observational, retrospective, and cross-sectional studies related to Chagas Disease in the Amazon region of Brazil was conducted, and a case series addressing CCC in patients treated at the FMT-HVD outpatient clinic, a reference center for Chagas disease in Brazil, was carried out.

Results

Clinical characteristics of 55 patients from the Amazon region with CCC were described. The most common electrocardiographic alteration observed was abnormal ventricular repolarization (AVR), present in 40% of cases. The most common echocardiographic finding was left ventricular systolic dysfunction (49%), followed by akinesia or hypokinesia of the inferior and/or inferolateral walls (38.1%) and the presence of an apical aneurysm (32.7%).

Conclusions

Overall, this study demonstrates that CCC in the Amazon region presents clinical characteristics and severity that are similar to those observed in other regions. However, certain peculiarities, such as the frequency of right bundle branch block (RBBB) and anterior and septal involvement during the acute phase, require additional investigation to better comprehend the disease in the region. Overall, the study provides crucial clinical insights for the diagnosis and treatment of CCC in the Amazon region.

Correlation of TcII discrete typing units with severe chronic Chagas cardiomyopathy in patients from various Brazilian geographic regions

BACKGROUND

Chagas disease (ChD) is caused by Trypanosoma cruzi. The genetic structure of the species is divided into seven distinct genetic groups, TcI to TcVI, and Tcbat, which have shown differences in terms of geographic distribution, biological properties, and susceptibility to drugs. However, the association between genetic variability and clinical forms of ChD has not yet been fully elucidated. The predominance of TcII and TcVI discrete typing units (DTUs) (genetic groups) is known to occur in several Brazilian regions and is associated with both the domestic and the wild cycles of ChD. Thus, this study aimed to verify the genotypes of the parasites present in 330 patients with chronic Chagas cardiomyopathy (CCC) from different Brazilian states attended at the Clinical Hospital of the Ribeirão Preto Medical School and to assess the existence of a correlation between the clinical forms with the main cardiovascular risk factors and the genetics of the parasite.

METHODOLOGY PRINCIPAL FINDINGS

All patients with CCC were clinically evaluated through anamnesis, physical examination, biochemical tests, 12-lead electrocardiogram, echocardiogram and chest X-ray. Peripheral blood (5 mL) was collected in guanidine/ethylenediaminetetraacetic acid from each patient for DNA extraction and real-time polymerase chain reaction (PCR) for Chagas disease and genotyping of the parasite in the 7 DTUs. Parasite genotyping was performed using conventional multilocus PCR. Samples of only 175 patients were positive after amplification of the specific genes contained in the T. cruzi genotyping criteria. TcII (64/175), TcVI (9/175), and TcI (3/175) DTUs were predominant, followed by TcII/TcV/TcVI (74/175), and TcII/TcVI (23/175). The TcIII and TcIV DTU´s was detected in only one sample of CCC patients.

CONCLUSIONS/SIGNIFICANCE

Our data corroborate previous findings, indicating the predominance of the TcII genotype in patients with CCC of Brazilian origin. Moreover, this study pioneered disclosing a direct correlation between the TcII DTU and severe CCC.

Association of left ventricular abnormalities with incident cerebrovascular events and sources of thromboembolism in patients with chronic Chagas cardiomyopathy

BACKGROUND

Although Chagas cardiomyopathy is related to thromboembolic stroke, data on risk factors for cerebrovascular events in Chagas disease is limited. Thus, we assessed the relationship between left ventricular (LV) impairment and cerebrovascular events and sources of thromboembolism in patients with Chagas cardiomyopathy.

METHODS

This retrospective cohort included patients with chronic Chagas cardiomyopathy who underwent cardiovascular magnetic resonance (CMR). CMR was performed with a 1.5 T scanner to provide LV volumes, mass, ejection fraction (LVEF), and myocardial fibrosis. The primary outcome was a composite of incident ischemic cerebrovascular events (stroke or transient ischemic attack-TIA) and potential thromboembolic sources (atrial fibrillation (AF), atrial flutter, or intracavitary thrombus) during the follow-up.

RESULTS

A total of 113 patients were included. Median age was 56 years (IQR: 45-67), and 58 (51%) were women. The median LVEF was 53% (IQR: 41-62). LV aneurysms and LV fibrosis were present in 38 (34%) and 76 (67%) individuals, respectively. The median follow-up time was 6.9 years, with 29 events: 11 cerebrovascular events, 16 had AF or atrial flutter, and two had LV apical thrombosis. In the multivariable model, only lower LVEF remained significantly associated with the outcomes (HR: 0.96, 95% CI: 0.93-0.99). Patients with reduced LVEF lower than 40% had a much higher risk of cerebrovascular events and thromboembolic sources (HR: 3.16 95% CI: 1.38-7.25) than those with normal LVEF. The combined incidence rate of the combined events in chronic Chagas cardiomyopathy patients with reduced LVEF was 13.9 new cases per 100 persons-year.

CONCLUSIONS

LV systolic dysfunction is an independent predictor of adverse cerebrovascular events and potential sources of thromboembolism in patients with chronic Chagas cardiomyopathy.

Hospitalization for Chagas Heart Disease in the United States From 2002 to 2017

This cross-sectional study examines characteristics and outcomes of estimated discharges for Chagas heart disease in the United States from 2002 to 2017.

Detection of Trypanosoma cruzi by PCR in adults with chronic Chagas disease treated with nifurtimox

Chagas disease, a vector-borne parasitosis caused by Trypanosoma cruzi, is endemic to Latin America and has spread to other countries due to immigration of infected persons. It is estimated that 160,000 people are infected in Chile, most of them in the chronic phase and without etiological treatment. The infection is confirmed by conventional serological methods while molecular methods have become in valuable tools to evaluate parasitemia in treated and non-treated chronic Chagas disease patients. The objective of this study was to determine, by conventional Polymerase Chain Reaction, the presence of T. cruzi kinetoplastid DNA in peripheral blood samples from 114 adult individuals with confirmed chronic Chagas disease, before and 6.6 years (average) after treatment with nifurtimox. The samples were received and preserved in guanidine-EDTA until DNA purification. Conventional PCR assays were performed in triplicate with T. cruzi kinetoplastid DNA primers 121 and 122. The amplified products were fractionated by electrophoresis in 2% agarose gels. A 330 bp product represented a positive assay. 84.2% (96 cases) and 6.1% (7 cases) of the samples taken before and after the treatment, respectively, were positive. The McNemar test showed a statistically significant difference between the groups of samples (p<0.001). Since serological negativization (the current cure criterion) delay many years after therapy and positive parasitological results represent a treatment failure, the conversion of pre-therapy positive conventional PCR is a qualitative and complementary tool that could be included in protocols of prolonged follow-up.

Benznidazole Use among Patients with Chronic Chagas' Cardiomyopathy in an Endemic Region of Brazil

Chagas disease (CD) is a neglected tropical disease that affects individuals in almost every country in Latin America. There are two available drugs with antiparasitic profiles; however, only benznidazole (BZN) has been approved for commercialization in Brazil. The usefulness of prescribing BZN for patients with chronic Chagas cardiomyopathy (CCC) is controversial. There are no studies in the literature describing the extent of BZN use at this stage or the profile of patients using this drug. The present study aimed to determine the prevalence and factors associated with previous BZN use among individuals with CCC. This cross-sectional study was conducted with 1,812 individuals with CCC from 21 Brazilian cities endemic for CD. The dependent variable was "prior use of BZN" (no vs. yes). The independent variables were grouped into socioeconomic, lifestyle and medical history aspects. Binary logistic regression (α ≥ 0.05) was used. Among the evaluated individuals, 27.2% reported previous use of BZN. The likelihood of prior use of BZN was higher among younger individuals (OR = 2.7), individuals with a higher education (OR = 2.7), individuals with a lower monthly per capita income (OR = 1.3), individuals who practiced physical exercise (OR = 1.5), individuals who had prior knowledge of the CD diagnosis (OR = 2.5), individuals without hypertension (OR = 1.3) and individuals with a longer time to the CD diagnosis (OR = 6.1). The present study revealed a small proportion of therapeutic BZN use among Brazilian CCC patients. This finding suggests a late diagnosis and undertreatment of the disease. BZN use was higher among individuals with better clinical and demographic conditions but with a lower income and a longer time to the CD diagnosis. Knowledge of the BZN usage profile may help reduce the current state of neglect of this disease and pave the way for future studies.

Chronic Chagas cardiopathy in Chile. Importance of Trypanosoma cruzi burden and clinical evaluation

Currently there are no biological markers to indicate which individuals with chronic indeterminate period of Chagas disease develop heart disease and who will remain all his life in this phase. The aim of this survey was to determine if Trypanosoma cruzi burden is related to the presence of heart disease in patients with chronic Chagas disease. 200 patients who had not been treated, 100 with cardiopathy and 100 without, groups A and B respectively, were submitted to clinical study and electrocardiogram, Echo-Doppler was performed for group A in which all important known causes of cardiopathy were discarded. In both groups xenodiagnosis, conventional PCR and quantitative PCR were undertaken. The 100 cardiopaths had 133 electrocardiographic alterations most of them in grade II of the New York Heart Association classification. 98 cardiopaths were classified in grade I by Echo-Doppler and only 2 cases were in grade III due to low ejection fraction. The difference in average parasitemia in patients of group A and B was not significant and no statistically differences were observed between average parasitemia of cardiopaths grade II versus grade I of NYHA. This results allow to characterize same clinical, electrocardiographical and parasitological features in chagasic cardiopaths of Chile.

Genomic African and Native American Ancestry and Chagas Disease: The Bambui (Brazil) Epigen Cohort Study of Aging

BACKGROUND

The influence of genetic ancestry on Trypanosoma cruzi infection and Chagas disease outcomes is unknown.

METHODOLOGY/PRINCIPAL FINDINGS

We used 370,539 Single Nucleotide Polymorphisms (SNPs) to examine the association between individual proportions of African, European and Native American genomic ancestry with T. cruzi infection and related outcomes in 1,341 participants (aged ≥ 60 years) of the Bambui (Brazil) population-based cohort study of aging. Potential confounding variables included sociodemographic characteristics and an array of health measures. The prevalence of T. cruzi infection was 37.5% and 56.3% of those infected had a major ECG abnormality. Baseline T. cruzi infection was correlated with higher levels of African and Native American ancestry, which in turn were strongly associated with poor socioeconomic circumstances. Cardiomyopathy in infected persons was not significantly associated with African or Native American ancestry levels. Infected persons with a major ECG abnormality were at increased risk of 15-year mortality relative to their counterparts with no such abnormalities (adjusted hazard ratio = 1.80; 95% 1.41, 2.32). African and Native American ancestry levels had no significant effect modifying this association.

CONCLUSIONS/SIGNIFICANCE

Our findings indicate that African and Native American ancestry have no influence on the presence of major ECG abnormalities and had no influence on the ability of an ECG abnormality to predict mortality in older people infected with T. cruzi. In contrast, our results revealed a strong and independent association between prevalent T. cruzi infection and higher levels of African and Native American ancestry. Whether this association is a consequence of genetic background or differential exposure to infection remains to be determined.

Electrocardiographic Abnormalities and Treatment with Benznidazole among Children with Chronic Infection by Trypanosoma cruzi: A Retrospective Cohort Study

Background

Chronic infection by Trypanosoma cruzi could cause heart conduction disturbances. We sought to analyze electrocardiographic abnormalities among children with chronic T. cruzi infection with and without trypanocidal treatment with benznidazole.

Methodology/Principal Findings

We studied 111 children 6–16 years of age with asymptomatic chronic T. cruzi infection who were recruited in 1991–1992 in Salta, Argentina. Most children were randomly assigned to benznidazole 5 mg/Kg/day (n = 47) or matching placebo (n = 48) for 60 days. Remaining children (n = 16) received treatment with benznidazole 5 mg/Kg/day open-label. Electrocardiograms were obtained at baseline and in 1995–1996, 1998, 2000 and 2005, and were analyzed using the Buenos Aires method. Among the 94 children with an electrocardiogram at baseline, 8 (8.5%) had electrocardiographic abnormalities, including 4 (4.7%) children with right bundle branch block. Proportion of abnormal electrocardiograms in the full population (n = 111) remained constant over time (media follow-up 8.6 years). Multivariable adjusted prevalence ratios (95% confidence interval [95%CI]) for electrocardiographic abnormalities in 1995–1996, 1998, 2000 and 2005 comparing children treated with benznidazole versus those not treated were 2.76 (0.66, 11.60), 2.33 (0.44, 12.31), 3.06 (0.48, 19.56), and 1.94 (0.33, 11.25), respectively. Among the 86 children with a normal electrocardiogram at baseline, 16 (18.6%) developed electrocardiographic abnormalities during follow-up. The multivariable adjusted hazard ratio for incident electrocardiographic abnormalities comparing children treated with benznidazole versus those not treated was 0.68 (95%CI: 0.25, 1.88).

Conclusions/Significance

Electrocardiographic abnormalities are frequent among children with chronic T. cruzi infection. Treatment with benznidazole for 60 days may not be associated with less electrocardiographic abnormalities.

There are few data available on the natural history of electrocardiographic abnormalities among children with chronic Trypanosoma cruzi infection. Also, few studies analyzed the effect of benznidazole to prevent electrocardiographic abnormalities in this population. In the current study, electrocardiographic abnormalities were frequent among children with chronic T. cruzi infection. Results from the current study also suggest that treatment with benznidazole may not be associated with less electrocardiographic abnormalities. The current study highlights the need of further research to prevent cardiovascular manifestations associated with chronic T. cruzi infection.

Longitudinal study of patients with chronic Chagas cardiomyopathy in Brazil (SaMi-Trop project): a cohort profile

PURPOSE

We have established a prospective cohort of 1959 patients with chronic Chagas cardiomyopathy to evaluate if a clinical prediction rule based on ECG, brain natriuretic peptide (BNP) levels, and other biomarkers can be useful in clinical practice. This paper outlines the study and baseline characteristics of the participants.

PARTICIPANTS

The study is being conducted in 21 municipalities of the northern part of Minas Gerais State in Brazil, and includes a follow-up of 2 years. The baseline evaluation included collection of sociodemographic information, social determinants of health, health-related behaviours, comorbidities, medicines in use, history of previous treatment for Chagas disease, functional class, quality of life, blood sample collection, and ECG. Patients were mostly female, aged 50-74 years, with low family income and educational level, with known Chagas disease for >10 years; 46% presented with functional class >II. Previous use of benznidazole was reported by 25.2% and permanent use of pacemaker by 6.2%. Almost half of the patients presented with high blood cholesterol and hypertension, and one-third of them had diabetes mellitus. N-terminal of the prohormone BNP (NT-ProBNP) level was >300 pg/mL in 30% of the sample.

FINDINGS TO DATE

Clinical and laboratory markers predictive of severe and progressive Chagas disease were identified as high NT-ProBNP levels, as well as symptoms of advanced heart failure. These results confirm the important residual morbidity of Chagas disease in the remote areas, thus supporting political decisions that should prioritise in addition to epidemiological surveillance the medical treatment of chronic Chagas cardiomyopathy in the coming years. The São Paulo-Minas Gerais Tropical Medicine Research Center (SaMi-Trop) represents a major challenge for focused research in neglected diseases, with knowledge that can be applied in primary healthcare.

FUTURE PLANS

We will continue following this patients' cohort to provide relevant information about the development and progression of Chagas disease in remotes areas, with social and economic inequalities.

TRIAL REGISTRATION NUMBER

NCT02646943; Pre-results.

[Risk factors associated with the diagnosis of chronic Chagasic miocardiopathy in seropositive individuals from Barinas state, Venezuela]

This study evaluates the risk factors associated with the diagnosis of chronic chagasic miocardiopathy (CChM) in 115 seropositive individuals to anti-Trypanosoma cruzi antibodies, in Barinas state, Venezuela. Serology was performed with ELISA and MABA; while the CChM diagnosis was established by electrocardiography and echocardiography. A complete clinical history including epidemiological, personal/familiar antecedents and psychobiological habits, plus socioeconomic, psychosocial and alimentary habits interviews were performed for each individual. Risk factors were determined through binary logistic regression. Results showed that 81 patients (70,4%; CI 95% = 66.4-74.4) had criteria for CChM, of which 74 (64.4%; IC 95% = 60.2-68.6) were in phase II; while 34 (29.6%; IC 95% = 25.5-33.5) were in phase I of the disease and 7 (6.1%; IC 95% = 4.0-8.2) in phase III. In a one year period, two patients in phase III died of heart failure. The diagnosis of CChM was associated with hunting practice, maternal history of cardiopathies, chewing chimó, medical history of hypertension and apex beat visible; it was negatively associated with canned and preserved foods ingest. In conclusion the CChM diagnosis has high frequency in seropositive individuals in Barinas and heart failure prevention must be based on an early medical attention and educative strategies in order to control risk factors.

Treatment of Chagas cardiomyopathy

Chagas' disease (ChD), caused by the protozoa Trypanosoma cruzi (T. cruzi), was discovered and described by the Brazilian physician Carlos Chagas in 1909. After a century of original description, trypanosomiasis still brings much misery to humanity and is classified as a neglected tropical disease prevalent in underdeveloped countries, particularly in South America. It is an increasing worldwide problem due to the number of cases in endemic areas and the migration of infected subjects to more developed regions, mainly North America and Europe. Despite its importance, chronic chagas cardiomyopathy (CCC) pathophysiology is yet poorly understood, and independently of its social, clinical, and epidemiological importance, the therapeutic approach of CCC is still transposed from the knowledge acquired from other cardiomyopathies. Therefore, the objective of this review is to describe the treatment of Chagas cardiomyopathy with emphasis on its peculiarities.

Immunopathologic characterization of naturally acquired Trypanosoma cruzi infection and cardiac sequalae in cynomolgus macaques (Macaca fascicularis)

Trypanosoma cruzi, the causative agent of Chagas disease, is endemic in south Texas due to the abundant vector and wild small mammalian reservoir populations. This situation predisposes nonhuman primate colonies exposed to outdoor housing to infection from ingestion or bite of triatomid insects. Using a T. cruzi-specific real-time PCR and Trypanosome spp.-specific ELISA, we revealed a prevalence rate of 8.5% in a colony of outdoor-housed cynomolgus macaques. By using a discriminating kinetoplastid minicircle PCR, we eliminated the possibility of mixed prevalence with nonpathogenic trypanosomes and showed the ELISA results were specific for T. cruzi. In this study, we found an inverse relationship between antibody titers and circulating parasite load. Also, 23% of T. cruzi IgG ELISA-positive macaques were negative by real-time PCR. Furthermore, in a subset of infected macaques, cardiac tissue was infiltrated by inflammatory mononuclear cells and contained T. cruzi genomic and kinetoplast DNA despite lacking microscopic evidence of discrete parasite stages. In addition, 19% of the infected macaques had titers for cardiac troponin I autoantibody, which could contribute to autoimmune myocarditis or interfere with circulating troponin I measurements. These findings indicate the possibility of T. cruzi to interfere with the assessment of cardiac safety signals in preclinical toxicology and safety pharmacology studies and the necessity for prestudy screening for T. cruzi in outdoor-housed nonhuman primates from endemic areas.

Global economic burden of Chagas disease: a computational simulation model

BACKGROUND

As Chagas disease continues to expand beyond tropical and subtropical zones, a growing need exists to better understand its resulting economic burden to help guide stakeholders such as policy makers, funders, and product developers. We developed a Markov simulation model to estimate the global and regional health and economic burden of Chagas disease from the societal perspective.

METHODS

Our Markov model structure had a 1 year cycle length and consisted of five states: acute disease, indeterminate disease, cardiomyopathy with or without congestive heart failure, megaviscera, and death. Major model parameter inputs, including the annual probabilities of transitioning from one state to another, and present case estimates for Chagas disease came from various sources, including WHO and other epidemiological and disease-surveillance-based reports. We calculated annual and lifetime health-care costs and disability-adjusted life-years (DALYs) for individuals, countries, and regions. We used a discount rate of 3% to adjust all costs and DALYs to present-day values.

FINDINGS

On average, an infected individual incurs US$474 in health-care costs and 0·51 DALYs annually. Over his or her lifetime, an infected individual accrues an average net present value of $3456 and 3·57 DALYs. Globally, the annual burden is $627·46 million in health-care costs and 806,170 DALYs. The global net present value of currently infected individuals is $24·73 billion in health-care costs and 29,385,250 DALYs. Conversion of this burden into costs results in annual per-person costs of $4660 and lifetime per-person costs of $27,684. Global costs are $7·19 billion per year and $188·80 billion per lifetime. More than 10% of these costs emanate from the USA and Canada, where Chagas disease has not been traditionally endemic. A substantial proportion of the burden emerges from lost productivity from cardiovascular disease-induced early mortality.

INTERPRETATION

The economic burden of Chagas disease is similar to or exceeds those of other prominent diseases globally (eg, rotavirus $2·0 billion, cervical cancer $4·7 billion) even in the USA (Lyme disease $2·5 billion), where Chagas disease has not been traditionally endemic, suggesting an economic argument for more attention and efforts towards control of Chagas disease.

FUNDING

Bill & Melinda Gates Foundation, the National Institute of General Medical Sciences Models of Infectious Disease Agent Study.

Electrocardiographic abnormalities in Trypanosoma cruzi seropositive and seronegative former blood donors

BACKGROUND

Blood donor screening leads to large numbers of new diagnoses of Trypanosoma cruzi infection, with most donors in the asymptomatic chronic indeterminate form. Information on electrocardiogram (ECG) findings in infected blood donors is lacking and may help in counseling and recognizing those with more severe disease.

OBJECTIVES

To assess the frequency of ECG abnormalities in T.cruzi seropositive relative to seronegative blood donors, and to recognize ECG abnormalities associated with left ventricular dysfunction.

METHODS

The study retrospectively enrolled 499 seropositive blood donors in São Paulo and Montes Claros, Brazil, and 483 seronegative control donors matched by site, gender, age, and year of blood donation. All subjects underwent a health clinical evaluation, ECG, and echocardiogram (Echo). ECG and Echo were reviewed blindly by centralized reading centers. Left ventricular (LV) dysfunction was defined as LV ejection fraction (EF)<0.50%.

RESULTS

Right bundle branch block and left anterior fascicular block, isolated or in association, were more frequently found in seropositive cases (p<0.0001). Both QRS and QTc duration were associated with LVEF values (correlation coefficients -0.159,p<0.0003, and -0.142,p = 0.002) and showed a moderate accuracy in the detection of reduced LVEF (area under the ROC curve: 0.778 and 0.790, both p<0.0001). Several ECG abnormalities were more commonly found in seropositive donors with depressed LVEF, including rhythm disorders (frequent supraventricular ectopic beats, atrial fibrillation or flutter and pacemaker), intraventricular blocks (right bundle branch block and left anterior fascicular block) and ischemic abnormalities (possible old myocardial infarction and major and minor ST abnormalities). ECG was sensitive (92%) for recognition of seropositive donors with depressed LVEF and had a high negative predictive value (99%) for ruling out LV dysfunction.

CONCLUSIONS

ECG abnormalities are more frequent in seropositive than in seronegative blood donors. Several ECG abnormalities may help the recognition of seropositive cases with reduced LVEF who warrant careful follow-up and treatment.

Chagas heart disease: report on recent developments

Chagas disease, caused by the parasite Trypanosoma cruzi, is an important cause of cardiac disease in endemic areas of Latin America. It is now being diagnosed in nonendemic areas because of immigration. Typical cardiac manifestations of Chagas disease include dilated cardiomyopathy, congestive heart failure, arrhythmias, cardioembolism, and stroke. Clinical and laboratory-based research to define the pathology resulting from T. cruzi infection has shed light on many of the cellular and molecular mechanisms leading to these manifestations. Antiparasitic treatment may not be appropriate for patients with advanced cardiac disease. Clinical management of Chagas heart disease is similar to that used for cardiomyopathies caused by other processes. Cardiac transplantation has been successfully performed in a small number of patients with Chagas heart disease.

B-type natriuretic peptide and anthropometric measures in a Brazilian elderly population with a high prevalence of Trypanosoma cruzi infection

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.

[Prevalence of positive serology to Trypanosoma cruzi in patients with clinical diagnosis of dilated myocardiopathy in the state of Campeche]

The prevalence of chronic Chagas' heart disease as a cause of dilated cardiomyopathy is unknown in the State of Campeche, Mexico. A study was conducted to determine the prevalence of positive serology for Trypanosoma cruzi in patients with clinical diagnosis of dilated cardiomyopathy. Of a total of 127 patients diagnosed with dilated cardiomyopathy, we studied 91 with two positive serological tests for T. cruzi. We identified 14 positive cases for a prevalence of 15 % of chronic Chagas' heart disease. This prevalence is similar to that reported for the rest of the Yucatan Peninsula.

[Chagas disease in the Netherlands: an estimate of the number of patients]

A total of 8-10 million persons are infected worldwide with Trypanosoma cruzi, the causative parasite of Chagas disease, most of whom are inhabitants of Latin America. Due to the increased migration of peoples, Chagas disease has been on the uprise outside Latin America, including in Europe. The course of Chagas, also called American trypanosomiasis, runs in 2 phases: an acute phase lasting approximately 2 months, and a chronic phase in which symptoms may appear years after infection. Without treatment, the patient will remain infected for life. The acute phase is usually asymptomatic; in the chronic phase of American trypanosomiasis, severe gastro-intestinal and cardiac abnormalities may develop, finally with fatal course. In the Netherlands, the number of immigrants who would serologically test positive for American trypanosomiasis is estimated to be between 726 and 2929. Healthcare providers in the Netherlands may encounter patients who have Chagas disease more and more frequently. The screening of pregnant women and blood donors at risk for American trypanosomiasis should be considered.

Chagas cardiomyopathy in the context of the chronic disease transition

BACKGROUND

Patients with Chagas disease have migrated to cities, where obesity, hypertension and other cardiac risk factors are common.

METHODOLOGY/PRINCIPAL FINDINGS

The study included adult patients evaluated by the cardiology service in a public hospital in Santa Cruz, Bolivia. Data included risk factors for T. cruzi infection, medical history, physical examination, electrocardiogram, echocardiogram, and contact 9 months after initial data collection to ascertain mortality. Serology and PCR for Trypanosoma cruzi were performed. Of 394 participants, 251 (64%) had confirmed T. cruzi infection by serology. Among seropositive participants, 109 (43%) had positive results by conventional PCR; of these, 89 (82%) also had positive results by real time PCR. There was a high prevalence of hypertension (64%) and overweight (body mass index [BMI] >25; 67%), with no difference by T. cruzi infection status. Nearly 60% of symptomatic congestive heart failure was attributed to Chagas cardiomyopathy; mortality was also higher for seropositive than seronegative patients (p = 0.05). In multivariable models, longer residence in an endemic province, residence in a rural area and poor housing conditions were associated with T. cruzi infection. Male sex, increasing age and poor housing were independent predictors of Chagas cardiomyopathy severity. Males and participants with BMI

CONCLUSIONS

Chagas cardiomyopathy remains an important cause of congestive heart failure in this hospital population, and should be evaluated in the context of the epidemiological transition that has increased risk of obesity, hypertension and chronic cardiovascular disease.

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Key Words Collapse

MESH Headings

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Antibodies, Protozoan/blood
• Bolivia/epidemiology
• Chagas Cardiomyopathy/complications
• Chagas Cardiomyopathy/epidemiology
• Chagas Cardiomyopathy/mortality
• Chagas Cardiomyopathy/pathology
• Chronic Disease
• DNA, Protozoan/blood
• Enzyme-Linked Immunosorbent Assay
• Female
• Heart Failure/epidemiology
• Heart Failure/etiology
• Humans
• Male
• Middle Aged
• Polymerase Chain Reaction
• Prevalence
• Risk Factors
• Trypanosoma cruzi/genetics
• Trypanosoma cruzi/immunology
• Trypanosoma cruzi/isolation & purification
• Young Adult

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Grants

• 5 P50 AI074285 NIAID NIH HHS
• P50 AI074285 NIAID NIH HHS
• R24 TW007988 FIC NIH HHS
• T35 AI065385 NIAID NIH HHS
• 5 T35 AI065385 NIAID NIH HHS
• D43 TW006581 FIC NIH HHS
• R24TW007988 FIC NIH HHS

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Affiliation(s)

Alicia I. Hidron Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
Robert H. Gilman Asociacion Benefica PRISMA, Lima, Peru Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
Juan Justiniano Hospital Universitario Japones, Santa Cruz de la Sierra, Bolivia
Anna J. Blackstock Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America Atlanta Research and Education Foundation, Decatur, Georgia, United States of America
Carlos LaFuente Hospital Universitario Japones, Santa Cruz de la Sierra, Bolivia
Walter Selum Hospital Universitario Japones, Santa Cruz de la Sierra, Bolivia
Martiza Calderon Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
Manuela Verastegui Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
Lisbeth Ferrufino Hospital Universitario Japones, Santa Cruz de la Sierra, Bolivia
Eduardo Valencia Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
Jeffrey A. Tornheim Mount Sinai School of Medicine, New York, New York, United States of America
Seth O'Neal Oregon Health Sciences University, Portland, Oregon, United States of America
Robert Comer Wake Forest University Health Sciences, Winston-Salem, North Carolina, United States of America
Gerson Galdos-Cardenas Asociacion Benefica PRISMA, Lima, Peru
Caryn Bern Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
for the Chagas Disease Working Group in Peru and Bolivia

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Trypanosoma cruzi circulating in the southern region of the State of Mexico (Zumpahuacan) are pathogenic: a dog model

Here we describe clinical and pathologic evidence of Chagas disease caused in dogs by circulating Trypanosoma cruzi from a newly recognized endemic area in Mexico. We show that the Zumpahuacan isolate, although less virulent than the Sylvio-X10 reference strain that caused acute myocarditis and death, was pathogenic in dogs. Dogs infected with the Zumpahuacan isolate exhibited electrocardiographic alterations, left- and right-ventricle dilation, and hydropericardium. Histologically, diffused perimysial and endomysial lymphoplasmacytic cell infiltration, cardiomyocyte necrosis, and amastigote nests were noted in Zumpahuacan-infected dogs. These findings suggest that the risk of T. cruzi infection and Chagas disease is present in the State of Mexico, and further research is needed to identify the T. cruzi bio-types circulating in southern State of Mexico.

Perspectives on Trypanosoma cruzi-induced heart disease (Chagas disease)

Chagas disease is caused by the parasite Trypanosoma cruzi. It is a common cause of heart disease in endemic areas of Latin America. The year 2009 marks the 100th anniversary of the discovery of T cruzi infection and Chagas disease by the Brazilian physician Carlos Chagas. Chagasic cardiomyopathy develops in from 10% to 30% of persons who are chronically infected with this parasite. Echocardiography and magnetic resonance imaging (MRI) are important modalities in the evaluation and prognostication of individuals with chagasic heart disease. The etiology of chagasic heart disease likely is multifactorial. Parasite persistence, autoimmunity, and microvascular abnormalities have been studied extensively as possible pathogenic mechanisms. Experimental studies suggest that alterations in cardiac gap junctions may be etiologic in the pathogenesis of conduction abnormalities. The diagnosis of chronic Chagas disease is made by serology. The treatment of this infection has shortcomings that need to be addressed. Cardiac transplantation and bone marrow stem cell therapy for persons with Chagas disease have received increasing research attention in recent years.

[Migration flow and imported diseases: chronic chagasic cardiomyopathy]

Chagas disease, caused by the parasite Trypanosoma cruzi, is transmitted by triatomine bugs in endemic regions of the American continent and less frequently by blood transfusion and congenital transmission. Immigration rates explain why the disease can be found worldwide. Non-endemic countries that receive a significant amount of Latin American immigrants should be familiarized with the disease to allow prevention, diagnosis and early treatment. In Italy, where no serologic screening is routinely performed to detect Trypanosoma cruzi in blood donations, a special consideration must be held. Accordingly, attention to congenital transmissions of the disease should be drawn considering the lack of newborn screening. Though commonly unrecognized, chronic chagasic cardiomyopathy is the most common type of chronic myocarditis in the world.

The challenges of Chagas Disease-- grim outlook or glimmer of hope

The authors discuss the key challenges that undermine the control of Chagas disease and that must be urgently addressed to ensure long-term, sustainable control.

[Frequency of Trypanosoma cruzi infection in patients with implanted pacemaker]

INTRODUCTION

In Colombia the impact of infections of Trypanosoma cruzi are known to produce chronic cardiopathy and expressed by bradycardia. In Colombia the extent and impact of these infections has not been examined.

OBJECTIVE

The current study aimed to determine the prevalence of T. cruzi infection as measured by serology, in a population of patients with cardiopathy that required a permanent pacemaker as treatment for cardiac rhythm abnormalities and conduction blocking.

MATERIALS AND METHODS

A cross sectional study sampled 332 patients from the pacemaker clinic at the San Pedro Claver Hospital in Bogotá, Colombia, for one year (2004-2005). Epidemiological and clinical data were obtained through interviews and physical examination. Serological tests consisted of indirect inmunofluorescence assay and ELISA. Statistical analyses were accomplished with chi-square and Students t tests.

RESULTS

Of patients with pacemakers, 17.1% had anti-T. cruzi antibodies (seropositive). At the time when the pacemaker was implanted, chronic Chagas disease patients were younger (55+/-13 years) than those patients with cardiopathy (60+/-17 years) with no anti-T. cruzi antibodies (p<0.01). The seropositive group was aware of the Chagas disease vector (83.6%) in contrast to the seronegative group (39.6%, p<0.001). In 60% of the patients of the seropositive group, no clinical signs of the disease were apparent. The geographical origin of the seropositive group were traced to regions in Colombia known to be endemic for Chagas disease transmission.

CONCLUSION

Chagas disease prevalence is high in Colombian patients who required a permanent cardiac pacemaker. Chronic Chagas disease patients required pacemaker implant at a younger age in contrast with patients with other cardiac pathologies. The clinical recognition of Chagas disease associated with cardiopathy is low despite the epidemiological data.

Natural products to anti-trypanosomal drugs: an overview of new drug prototypes for American Trypanosomiasis

Protozoan tropical diseases cause great suffering throughout developing countries, with high rates of morbidity and mortality. American Trypanosomiasis affects 16-18 million people in Latin America, representing a dramatic disease among symptomatic patients. Old, toxic and ineffective chemotherapeutic agents continue to be used for the treatment of Chagas' disease. Since the early days of medicine, chemical substances derived from plants and animals have been used to treat human diseases. In the marine ecosystem ecological pressures, such as competition for space and predation, may have favored several invertebrate organisms to select unique metabolites with an assortment of astonishing biological activities. In terrestrial ecosystems, amphibians present a unique efficient skin secretion system with a variety of glands which produce a myriad of potent bioactive compounds such as peptides, alkaloids, biogenic amines and lipids. Plants contribute with several antitrypanosomal compounds derived mainly from their secondary metabolism. Proteins and peptides from snake venoms have also been considered as novel drug candidates, showing effective activities. In this review, we broadly discuss the epidemiology, pathology, and current treatment of Chagas' disease as well as the contributions of pharmacologically tested marine invertebrate, amphibian, snake and plant compounds which have shown promising antitrypanosomal activities. We also explore these possibilities for developing new chemotherapeutics against Chagas' disease.

An update on the management of Chagas cardiomyopathy

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, infects nearly 18 million people in Latin America and mainly affects the heart, causing heart failure, arrhythmias, heart block, thromboembolism, stroke and death. In this review, the clinical diagnosis and management of Chagas cardiomyopathy are discussed. Particular emphasis is placed on the clinical staging of patients and the use of various diagnostic tests that may be useful in individualizing treatment of the two most relevant clinical syndromes, that is, heart failure and arrhythmias. The relevance of specific treatments are discussed, stressing the important role of parasite persistence in disease pathogenesis. We also discuss new therapy modalities that may have a role in the treatment of Chagas cardiomyopathy.

Chagas' disease and the use of implantable cardioverter-defibrillators in Brazil

The authors discuss the epidemiology and pathogenesis of Chagas' disease in Brazil, including the use of treatment with a cardioverter-defibrillator in patients with low ejection fraction. Select patients may benefit from resynchronization therapy associated with cardioverter-defibrillator treatment. Electrophysiologic study is indicated in the assessment of the potential utility of an implantable cardioverter-defibrillator.

Manifestations of Chagas disease (American trypanosomiasis) in patients with HIV/AIDS

Between June 1989 and December 2005, an observational study of adults co-infected with HIV and Trypanosoma cruzi was conducted, to investigate the spectrum of manifestations of chronic Chagas disease (American trypanosomiasis) in the HIV-positive. The 31 men and 22 women investigated were aged 23-59 years. Each subject was investigated by ambulatory (Holter) and non-ambulatory electrocardiography, chest X-ray, oesophagography and echocardiography (to determine the clinical form of trypanosomiasis), by xenodiagnosis, blood culture and the microscopical examination of blood (to explore their T. cruzi parasitaemia), and by counting their CD4 T cells (to stage their HIV infection). The subjects were followed-up for 1-190 months (median = 58 months) and checked for re-activation of their Chagas disease, which was usually defined by the occurrence of unusual clinical manifestations and/or the detection, by microscopical examination, of trypanosomes in the blood or cerebrospinal fluid. Eleven (20.8%) of the subjects showed re-activation, another nine (17.0%) were found to have developed high T. cruzi parasitaemias but these were only detected by xenodiagnosis or culture, and 15 (28.3%) had illnesses typical of chronic Chagas disease in HIV-negative individuals, with low parasitaemias. Anti-T. cruzi therapy (benznidazole), recommended for 17 patients, resulted in the sustained reduction of parasitaemia in 11 of the 12 subjects who completed treatment. Chagas disease was the cause of death of eight of the 14 subjects who died during the study. Four of the women investigated gave birth, each to a single child, during follow-up, and three of the four babies showed evidence of the congenital transmission of T. cruzi.

Clinical aspects of the Chagas' heart disease

Chagas' heart disease, caused by protozoan Trypanosoma cruzi, is a common cause of cardiomyopathy in the Americas. Transmission of T. cruzi occurs through Reduviids, the kissing bugs. Less common ways of transmission are blood transfusion, congenital transmission, organ transplantation, laboratory accident, breastfeeding, and oral contamination. Infestation results in cardiac dysautonomia, myocardial apoptosis, and myocardial fibrosis. In acute phase, death is mostly caused by myocarditis and in chronic phase, it is mostly by irreversible cardiomyopathy. A majority of the patients with Chagas' disease remain in the latent phase of disease for 10 to 30 years or even for life. Specific anti-Chagas' therapy with trypanocide drugs is useful in acute phase but the management of chronic Chagas' heart disease is mostly empirical. The mortality during the acute phase of cardiac Chagas is around 5%. Five-year mortality of chronic Chagas' disease with cardiac dysfunction is above 50%. The clinical aspects of the Chagas' heart disease are concisely reviewed.

Lack of association of tumor necrosis factor-α polymorphisms with Chagas disease in Brazilian patients

One third of Trypanosoma cruzi-infected individuals develop chronic Chagas disease cardiomyopathy (CCC) while the majority remains asymptomatic (ASY). About 30% of CCC patients develop heart failure due to end-stage inflammatory dilated cardiomyopathy. Increased production of tumor necrosis factor (TNF)-alpha has been described in all clinical forms of Chagas disease, and the highest levels are detected in CCC patients with severe ventricular dysfunction. Genetic susceptibility may play a role in the clinical outcome of Chagas disease. We investigated TNF as a candidate gene for susceptibility to development and/or progression of CCC. We analyzed the TNFa microsatellite and the -308 TNF promoter polymorphisms, in 166 CCC compared to 80 ASY geographically and age-matched patients in an association study. To analyze the association of TNF polymorphisms with progression of the cardiomyopathy, CCC patients were also grouped in three categories according to degree of left ventricular (LV) dysfunction into severe (n=57), mild to moderate (n=21) and absent (n=88). Our results show no significant differences either between CCC and ASY patients, or among CCC patients according to severity of cardiomyopathy with respect to TNFa or -308 TNF promoter polymorphisms. These results indicate that TNF polymorphisms are associated neither to CCC development nor to progression to more severe forms of cardiomyopathy in Brazilian Chagas disease patients.

[Chronic Chagasic Cardiomyopathy at the Hospital General de Zona no. 24 IMSS. Poza Rica, Veracruz]

Northern Veracruz has conditions, biotic and abiotic, to support Triatomine bugs and vectorial transmission of Trypanosoma cruzi to human beings. Therefore we explore seroprevalence of antibodies to this parasite and the presence of Chronic Chagasic Cardiopathy (CCC) at Cardiology ward in a General Hospital serving North of Veracruz State, and neighbord states Hidalgo, Puebla San Luis Potosi and Tamaulipas.

MATERIAL AND METHODS

We search for consecutive adult patients attending outpatient and beds assigned to Cardiology between March through September, 2003. An epidemiology questionnaire, clinical work up, chest roentgenogram, 12 lead peripheral EKG and transthoracic echocardiogram were performed in 240 female/males patients. All of them were bled to blindly search for T. cruzi antibodies.

RESULTS

Seroprevalence was 8%, 49 cases of dilated cardiomyopathy were diagnosed 23 attributed to chronic diseases such as systemic hypertension diabetes mellitus or ischemic heart disease 12 with idiopathic disease and 14 (29%) had CCC. The latter accumulated epidemiologic features suggestive of vectorial infection. Four additional individuals without CCC but having specific antibodies were considered indeterminate Chagasic cases.

DISCUSSION AND CONCLUSIONS

This case series identify American Trypanosomiasis among 19 people attending a Cardiology Service, and 14 of them had a severe heart disease linked to progressive and fatal course. This observation points out that Chagas disease could be a regional public health problem in Northern Veracruz.

Automatic Implantable Cardioverter-Defibrillators in Chagas' Heart Disease Patients with Malignant Ventricular Arrhythmias

A total of 46 consecutive Chagas' disease patients had an automatic cardioverter defibrillator implanted at our institution from October 1998 to January 2004. A retrospective longitudinal study was carried out to identity type of life-threatening ventricular arrhythmias as well as type of therapy delivered. Of these, 41 (91%) had been recovered from cardiac arrest. Five (15%) of 33 patients in whom echocardiography was done had no left ventricular function. Antiarrhythmic therapy was delivered to 37 (80%) patients during postimplant follow-up. Thirty-one of 37 (84%) patients received both shock and antitachycardia pacing, five (13%) only antitachycardia pacing, and one (3%) patient only shock. Median time to first shock was 16 days, varying from 1 to 576 days. Ventricular fibrillation was the cause of first shock in 12 patients (32%), ventricular tachycardia in 11 (29%), and ventricular tachycardia not responding to antitachycardia pacing degenerating into ventricular fibrillation in nine (24%). Five patients with ventricular tachycardia were treated with antitachycardia pacing. Probability of freedom from device discharged was 47% at 90 days, 34% at 180 days, and 9% at 360 days in the postimplant follow-up. Thus, patients with chronic Chagas' heart disease recovered from cardiac arrest have a peculiar arrhythmogenic profile characterized by a high frequency of ventricular fibrillation and no left ventricular systolic dysfunction and a short period of time for first shock.

[Clinical and therapeutics aspects of heart failure due to Chagas disease]

OBJECTIVE

Describe the clinical and therapeutic characteristics of patients with heart failure (HF) secondary to chronic chagasic cardiomyopathy and evaluate if these characteristics are different from those found in other etiologies.

METHODS

A prospective analysis of the patients treated between August 2003 and June 2004 at a HF referral outpatient clinic was conducted.

RESULTS

Three hundred and fifty six patients diagnosed with HF were included in the study. Chagasic cardiomyopathy was the most common etiology (48% of the cases). Other etiologies included hypertensive cardiomyopathy in 19% of the patients, idiopathic dilated in 11% and ischemic in 9%. Patients with HF secondary to chagasic cardiomyopathy were more frequently from non-white ethnic groups (88 vs. 75%; p = 0.002), had a family history of Chagas disease (57 vs. 21%; p = 0.001), had the disease for a longer length of time (71 vs. 56 months; p = 0.034), had lower levels of education (4.4 +/- 4.1 vs. 5.7 +/- 4.2 years of study; p = 0.004), had a lower heart rate (69 +/- 12 vs. 73 +/- 13; p = 0.03) and a lower systolic blood pressure (121 +/- 25 vs. 129 +/- 28 mmHg; p = 0.006). There was also a higher incidence of the use of amiodarone (22 vs. 13%; p = 0.036) and artificial pacemakers (15 vs. 1%; p = 0.001). There was a lower usage of beta-blockers (39 vs. 59%; p = 0.001).

CONCLUSION

In this sample of HF outpatients, in a state with a high prevalence of Chagas disease, chagasic cardiomyopathy was the most common etiology and they presented some unique clinical and therapeutic characteristics in comparison to other heart failure patients.

The epidemiologic profile and prevalence of cardiopathy in Trypanosoma cruzi infected blood donor candidates, Londrina, Paraná, Brazil

To describe the epidemiologic profile and prevalence of cardiopathy in 163 Trypanosoma cruzi serum positive blood donor candidates, a descriptive study was carried out between August, 1996 and November, 1997 at the Londrina State University Chagas Disease Outpatient Clinic. The profile found was: young, average age 42.95 ± 8.62 years; male (65%); Caucasian (84%); low level of schooling; low family income; agricultural worker (26%); born in the state of Paraná (67%); from rural areas (85%); migrated to the city (85%); and the vector as the main mechanism of transmission. During the clinical characterization a chronic cardiac form was found in 38% of the patients and classified as cardiac suggestive form in 21% and little suggestive of Chagas disease in 17%. No significant difference was found among age group distribution, sex and the presence of cardiac symptoms in patients with or without cardiopathy. This study emphasizes the importance of expanding medical services to areas with a greater prevalence of infected individuals, in a hierarchical manner and aiming at decentralization.

Aspectos epidemiológicos, clínicos e parasitológicos da doença de Chagas em Mato Grosso do Sul

Com o objetivo de avaliar aspectos epidemiológicos, clínicos e parasitológicos da doença de Chagas crônica, em pacientes do Hospital Universitário da Universidade Federal de Mato Grosso do Sul, realizamos um estudo seccional envolvendo 120 chagásicos e 120 controles não-chagásicos, de ambos os sexos, com idades de 16 a 82 anos. Os aspectos epidemiológicos foram avaliados por questionário, a cardiopatia por exame clínico, eletrocardiograma convencional, radiologia e ecodopplercardiograma e a presença de Trypanosoma cruzi no sangue por xenodiagnóstico e teste da reação em cadeia da polimerase. Os resultados mostraram predominância de alóctones com baixa escolaridade e referência de contato prévio com triatomíneos entre os chagásicos. Abortamento espontâneo foi mais freqüente nas mulheres chagásicas. A cardiopatia devido ao componente chagásico foi estimada em 20,2%. Apresentou-se com 7,5% de cardiomegalia, 6,2% de aneurisma de ventrículo esquerdo e com predominância de dispnéia, palpitações e hipertensão arterial. O xenodiagnóstico foi positivo em 26,1% dos chagásicos enquanto a PCR foi positiva em 53,7%. A análise dos resultados indicou que a doença de Chagas no grupo estudado apresenta características clínicas e parasitológicas que revelam peculiaridades regionais.

Type 1 chemokine receptor expression in Chagas' disease correlates with morbidity in cardiac patients

Chemokines and chemokine receptors (CKRs) control the migration of leukocytes during the inflammatory process and are important immunological markers of type 1 (CCR5 and CXCR3) and type 2 (CCR3 and CCR4) responses. The coexpression of CKRs (CCR2, CCR3, CCR5, CXCR3, and CXCR4) and intracellular cytokines (interleukin-10 [IL-10], IL-4, tumor necrosis factor alpha [TNF-alpha], and gamma interferon [IFN-gamma]) on T CD4+ and CD8+ peripheral cells from individuals with indeterminate (IND) or cardiac (CARD) clinical forms of Chagas' disease after in vitro stimulation with Trypanosoma cruzi antigens, were evaluated in this study. The percentage of T CD4+ and CD8+ cells coexpressing CCR5 and IFN-gamma, CXCR3 and IFN-gamma, and CXCR3 and TNF-alpha were higher in CARD than in IND individuals; on the other hand, the percentage of T CD4+ or CD8+ cells coexpressing CCR3 and IL-10 or coexpressing CCR3 and IL-4 were lower in CARD individuals than in IND individuals. In addition, a significant positive correlation between the expression of CCR5 or CXCR3 and IFN-gamma was observed in CARD individuals contrasting with a significant positive correlation between the expression of CCR3 and IL-4 and of CCR3 and IL-10 in IND patients. These results reinforce the hypothesis that a T. cruzi-exacerbated specific type 1 immune response developed by CARD chagasic patients is associated with the development of heart pathology.

Miocardiopatía chagásica en España: un diagnóstico a tener en cuenta

Chagas' disease is an important public health problem in Latin America and one of the specific causes of dilated cardiomyopathy. Chronic chagasic cardiomyopathy is the worse result of this disease and its main cause of mortality. Rural migrations from endemic to nonendemic countries make possible observing affected patients in United States and Europe. We report the case of a patient with congestive heart failure who was diagnosed with chronic chagasic cardiomyopathy. This is the first case of chagasic dilated cardiomyopathy in Spain.

[Epidemiological and clinical outlook of chronic Chagas' heart disease in Mexico]

OBJECTIVE

To compare the epidemiological and clinical characteristics of chronic Chagas' heart disease to other dilated cardiomyopathies.

METHODS

A study comprising 128 patients from a heart disease center was carried out from 1993 to 2003. Of them, 51 (40%) were Trypasonoma cruzi positive. Epidemiological data was obtained through interviews and clinical and serological data from health services. Statistic analysis was conducted using the Chi-square, Fischer, Mann-Whitney or Students' t-test as well as multivariate analysis.

RESULTS

Chronic Chagas' disease patients were older (55+/-10 years old) than those patients with cardiopathy (42+/-17 years old). Most of them were born in rural areas (90% vs 68%), lived in poor (75% vs 16%), crowded households (45% vs 20%), together with domestic animals (71% vs 61%) and were aware of the Chagas' vector (73% vs 25%). Rhythm and conduction ECG abnormalities as well as permanent pacemaker were common among Chagas' patients (84% vs 55%, 78% vs 64% and 24% vs 10%, respectively). Congestive heart failure was more frequent among cardiomiopathy patients (88% vs 71%). Both groups had abnormal myocardial perfusion with normal epicardial arteries. Comorbidities were more frequent in cardiomiopathy patients than in chronic Chagas' disease patient (two cases only).

CONCLUSIONS

Chagas' disease is the most common cause of dilated cardiomiopathy in the study hospital. Due to its regional distribution in Mexico, it deserves special attention and control programs proven to be effective in other countries.

Peculiar Aspects of Cardiogenic Embolism in Patients with Chagas’ Cardiomyopathy: A Transthoracic and Transesophageal Echocardiographic Study

OBJECTIVES

We sought to detect cardiac thrombi by transthoracic and transesophageal echocardiography in patients with Chagas' cardiomyopathy and to determine the relationship of these thrombi with left ventricular systolic function and with the presence of stroke.

BACKGROUND

Thromboembolic events are a serious complication of Chagas' cardiomyopathy. Because most data come from autopsy studies, the prevalence of cardiac thrombi for patients who are clinically stable is unknown.

METHODS

A total of 75 patients (52 men; mean age 48 +/- 13 years) with Chagas' cardiomyopathy were prospectively studied by transthoracic and transesophageal echocardiography and followed for 24 +/- 10 months.

RESULTS

In all, 14 patients (19%) had a history of stroke at the time of enrollment and two had this complication at follow-up. Most patients (88%) were in New York Heart Association (NYHA) functional classes I and II and 9 (12%) were in classes III and IV. Mean ejection fraction was 40 +/- 13%. A total of 17 patients (23%) had left ventricular thrombus on transthoracic echocardiography and this finding was associated with a history of stroke ( P = .01). Apical aneurysm occurred in 35 patients (47%) and it was associated both with thrombus and stroke ( P = .04). Strokes were more frequent ( P = .04) among patients with mild systolic dysfunction (57% of patients with strokes were in NYHA I). Four patients (5%) had thrombi at the left atrial appendage, and one (1%) at the right atrial appendage. A total of 13 patients (17%) died at follow-up.

CONCLUSIONS

Stroke was frequent in Chagas' cardiomyopathy and associated with mild systolic dysfunction and with intracardiac thrombi. These occurred mainly in the typical apical aneurysm of Chagas' disease.

A modified and unifying neurogenic hypothesis can explain the natural history of chronic Chagas heart disease

The pathogenesis of chronic Chagas disease still is an unresolved and controversial issue. Parasite persistence and autoimmune responses cannot explain the spectrum of chronic Chagas disease. However, a modified neurogenic hypothesis, concerning the timing and mechanisms responsible for the cardiac parasympathetic damage and for the activation of the sympathetic nervous system and of other neurohormonal systems, unifies cardiac remodelling and neurohormonal activation to explain most of the events of the natural history of Chagas disease.

Chagas cardiomyopathy and serologic testing in a small rural hospital in Chiapas, Mexico

OBJECTIVES

To conduct a study in a small rural hospital located in the state of Chiapas, Mexico, to: (1) examine the prevalence of chagasic cardiomyopathy among patients with the diagnosis of congestive heart failure and (2) assess the prevalence of positive serologic results in blood donors in the hospital, in an attempt to ascertain whether Chagas' disease remains an important cause of heart failure at least in some areas of Mexico.

METHODS

The study of patients with cardiomyopathy was conducted by retrospective chart review of patients with the diagnosis of congestive heart failure treated at the hospital during the years 2000-2002. With the blood donors, the results of their serologic screening were reviewed for a six-month period beginning in April 2002. Serologic testing was done in both groups with either indirect hemagglutination (IHA) or enzyme-linked immunosorbent assay (ELISA), or with both.

RESULTS

Of 67 patients with heart failure and no risk factors for other causes of heart failure, 40 of them had serologic tests performed. Thirty-three of these 40 (82.5%) were positive by ELISA, IHA, or both. With 97 blood donors, one or both serologic tests were positive in 17 of them (17.5%).

CONCLUSIONS

This research adds to the evidence that Chagas' disease continues to be a major cause of heart failure in some areas of Mexico and that there continues to be a risk of transmission by blood transfusion if donated blood is not consistently screened.