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Chagas disease is a neglected tropical disease caused by the parasite Trypanosoma cruzi. Chronic Chagas cardiomyopathy (CCC), the most severe form of target organ involvement in Chagas disease, is characterized by a complex pathophysiology and a unique phenotype that differentiates it from other cardiomyopathies, highlighting its worse prognosis compared to other aetiologies of heart failure. The three pathophysiological mechanisms with the largest impact on this differential mortality include rapidly progressive heart failure, a high incidence of stroke, and a high burden of ventricular arrhythmias. However, despite significant advances in understanding the unique molecular circuits underlying these mechanisms, the new knowledge acquired has not been efficiently translated into specific diagnostic and therapeutic approaches for this unique cardiomyopathy. The lack of dedicated clinical trials and the limited CCC-specific risk stratification tools available are evidence of this reality. This review aims to provide an updated perspective of the evidence and pathophysiological mechanisms associated with the higher mortality observed in CCC compared to other cardiomyopathies and highlight opportunities in the diagnostic and therapeutic approaches of the disease., (© 2024 The Author(s). European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Background: Chagas cardiomyopathy (ChCC) is one of the causes of the implantation of pacemakers (PM) in many patients and has been associated with an adverse prognosis., Objectives: To compare the prognosis of the chagasic and non-chagasic populations undergoing PM and cardiac resynchronizer implantation., Methods: Observational, retrospective study, which analyzed a cohort of patients who underwent implantation of these devices, in a tertiary center, from October 2007 to December 2017, comparing the chagasic group with non-chagasic patients. The non-parametric Kaplan-Meier method was used to calculate patient survival. The significance level adopted in the statistical analysis was 5%. The primary outcome was mortality from any cause, while the secondary outcomes were the occurrence of hospitalization and the combination of hospitalization and death., Results: A total of 911 patients were included, of which 23.4% had ChCC. In a Cox analysis adjusted for sex and age, Chagas disease (ChD) was not associated with an increased risk of death (HR: 1.14, CI:95%, 0.86-1.51, p=0.365), hospitalization (HR: 0.79, CI:95%, 0.61-1.04, p=0.09) or combined outcome of death and hospitalization (HR: 0.90, CI:95%, 0.72-1 .12, p=0.49)., Conclusions: ChD was not associated with an increased risk of death, hospitalization, or combined outcome of death and hospitalization, even after adjustment for sex and age. These results contrast with those of previous studies and suggest changes in the quality of care of patients with cardiomyopathy.

Introduction and Objectives: Although multiple studies suggest that chronic Chagas cardiomyopathy (CCC) has higher mortality than other cardiomyopathies, the absence of meta-analyses supporting this perspective limits the possibility of generating robust conclusions. The aim of this study was to systematically evaluate the current evidence on mortality risk in CCC compared with that of other cardiomyopathies., Methods: PubMed/Medline and EMBASE were searched for studies comparing mortality risk between patients with CCC and those with other cardiomyopathies, including in the latter nonischemic cardiomyopathy (NICM), ischemic cardiomyopathy, and non-Chagas cardiomyopathy (nonCC). A random-effects meta-analysis was performed to combine the effects of the evaluated studies., Results: A total of 37 studies evaluating 17 949 patients were included. Patients with CCC had a significantly higher mortality risk compared with patients with NICM (HR, 2.04; 95%CI, 1.60-2.60; I 2 , 47%; 8 studies) and non-CC (HR, 2.26; 95%CI, 1.65-3.10; I 2 , 71%; 11 studies), while no significant association was observed compared with patients with ischemic cardiomyopathy (HR, 1.72; 95%CI, 0.80-3.66; I 2 , 69%; 4 studies) in the adjusted-measures meta-analysis., Conclusions: Patients with CCC have an almost 2-fold increased mortality risk compared with individuals with heart failure secondary to other etiologies. This finding highlights the need for effective public policies and targeted research initiatives to optimally address the challenges of CCC., (Copyright © 2024 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.)

Background: There are few retrospective and prospective studies on implantable cardioverter-defibrillators (ICD) in primary and secondary prevention of sudden death in chronic Chagas heart disease (CCHD)., Objectives: To describe the long-term evolution of patients with CCHD and ICD and to identify and analyze predictors of mortality and appropriate device therapy in this population., Methods: This was a historical prospective study with 117 patients with ICD and CCHD. Devices were implanted from January 2003 to December 2021. Predictors of appropriate therapies and long-term mortality were identified and analyzed. The level of statistical significance was p < 0.05., Results: Patients (n = 117) had a median follow-up of 61 months (25 to 121 months); they were predominantly male (74%), with a median age of 55 years (48 to 64 years). There were 43.6% appropriate shocks, 26.5% antitachycardia pacing (ATP), and 51% appropriate therapies. During follow-up, 46 patients (39.7%) died. Mortality was 6.2% person-years (95% confidence interval [CI]: 4.6 to 8.3), with 2 sudden deaths during follow-up. Secondary prevention (hazard ratio [HR] 2.1; 95% CI: 1.1 to 4.3; p = 0.029) and ejection fraction less than 30% (HR 1.8; 95% CI: 1.1 to 3.1; p < 0.05) were predictors of appropriate therapies. Intermediate Rassi score showed a strong association with the occurrence of ATP alone (p = 0.015). Functional class IV (p = 0.007), left ventricular ejection fraction < 30 (p = 0.010), and age above 75 years (p = 0.042) were predictors of total mortality., Conclusion: ICDs in CCHD showed a high incidence of appropriate activation, especially in patients with secondary prevention, low left ventricular ejection fraction, and intermediate Rassi score. Patients with congestive heart failure, elevated functional class, and age over 75 years showed elevated mortality. Survival function of patients with implantable cardioverter-defibrillators and chronic Chagas heart disease. A - According to New York Heart Association functional class; B - According to left ventricular ejection fraction; C - According to Rassi score. D - According to age. CCHD: chronic Chagas heart disease; HR: hazard ratio; ICD: implantable cardioverter-defibrillator.

Background: Prognosis of Chronic Chagasic Cardiomyopathy (CCC) patients depends on functional and clinical factors. Bradyarrhythmia requiring pacemaker is a common complication. Prognosis of these patients is poorly studied, and mortality risk factors are unknown. We aimed to identify predictors of death and to define a risk score for mortality in a large cohort of CCC patients with pacemaker., Methods: It was an observational, unicentric and prospective study. The endpoint was all-cause mortality. Cox regression was used to identify predictors of death and to define a risk score. Bootstrapping method was used to internal score validation., Results: We included 555 patients and after a mean follow-up of 3.7±1.5 years, 100 (18%) deaths occurred. Predictors of death were: right ventricular dysfunction (HR [hazard ratio] 2.24; 95%CI 1.41-3.53; P = 0.001); heart failure class III or IV (HR 2.16; 95% confidence interval [95%CI] 1.16-4.00; P = 0.014); renal disease (HR 2.14; 95%CI 1.24-3.68; P = 0.006); left ventricular end-systolic diameter > 44mm (HR 1.97; 95%CI 1.26-3.05; P = 0.003); atrial fibrillation (HR 1.94; 95%CI 1.25-2.99; P = 0.003) and cardiomegaly on X-ray (HR 1.87; 95%CI 1.10-3.17; P = 0.020). The score identified patients with: low (0-20 points), intermediate (21-30 points) and high risk (>31points). The optimism-corrected C-statistic of the predictive model was 0.751 (95% CI 0.696-0.806). Internal validation with bootstrapping revealed a calibration slope of 0.946 (95% CI 0.920-0.961), reflecting a small degree of over-optimism and C-statistic of 0.746 (95% CI 0.692-0.785)., Conclusions: This study identified predictors of mortality in CCC patients with pacemaker defining a simple, validated and specific risk score., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 de Lima Peixoto et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objectives: To analyse the effect of parasite load assessed by quantitative reverse transcription PCR (RT-qPCR) in serum on the prognosis of patients with chronic Chagas cardiomyopathy (CCM) after a 2-year follow-up., Methods: Prospective cohort study conducted between 2015 and 2017. One hundred patients with CCM were included. Basal parasitaemia levels of Trypanosoma cruzi (T. cruzi) were measured using a quantitative polymerase chain reaction (qPCR) test. The primary composite outcome (CO) was all-cause mortality, cardiac transplantation and implantation of a left ventricular assist device. Secondary outcomes were the baseline levels of serum biomarkers and echocardiographic variables., Results: After a 2 years of follow-up, the primary CO rate was 16%. A positive qPCR was not associated with a higher risk of the CO. However, when parasitaemia was evaluated by comparing tertiles (tertile 1: undetectable parasitaemia, tertile 2: low parasitaemia and tertile 3: high parasitaemia), a higher risk of the CO (HR 3.66; 95% CI 1.11-12.21) was evidenced in tertile 2. Moreover, patients in tertile 2 had significantly higher levels of high-sensitivity troponin T and cystatin C and more frequently exhibited an ejection fraction <50%., Conclusion: Low parasitaemia was associated with severity markers of myocardial injury and a higher risk of the composite outcome when compared with undetectable parasitaemia. This finding could be hypothetically explained by a more vigorous immune response in patients with low parasitaemia that could decrease T. cruzi load more efficiently, but be associated with increased myocardial damage. Additional studies with a larger number of patients and cytokine measurement are required to support this hypothesis., (© 2020 John Wiley & Sons Ltd.)

Chagas disease (ChD) is a parasitosis caused by the protozoan Trypanosoma cruzi (Tc). It is endemic to almost all Latin American countries, including the southern United States. The acute form of ChD and its actual incidence have rarely been described in Mexico, despite the extensive presence of favorable niches for its transmission. The objective of this study was to estimate the frequency of acute ChD in febrile patients at the central Pacific coast of Mexico. For this, we surveyed patients with persistent fever (5 to 10 days) in five hospitals at the Mexican states of Jalisco, Colima, and Nayarit in 2012. Samples were taken from a total of 485 patients to detect Tc in blood using the polymerase chain reaction (PCR) test and direct microscopic examination. Of these subjects, 10 were positive for PCR and none for microscopic examination (2% in 12 months). We adjusted this rate by the total people at risk in the area and obtained an incidence of 7.4/100,000 habs./year. The positive cases showed no association with sex, rural settlement, or pet ownership, only with the contact with Triatominae insects (odds ratio = 9.22 and confidence interval: 1.93-44.06). The clinical picture of positive patients showed an association with the diagnosis of lower respiratory tract infections. Meanwhile, only one fatal case showed the typical picture of acute fatal cardiomyopathy. The pulmonary manifestations of our patients suggest possible lung pathogenicity of Tc, which merits further investigation. Our findings differ markedly from the official reports for ChD. This difference suggests an underestimation of the disease. These findings urge the Mexican health authorities to implement more vigorous actions aimed at improving medical skills in the timely diagnosis of ChD, as well as to apply efficient preventive programs.

Background: Left ventricular aneurysm (LVA) is indicator of high morbidity in Chagas' disease. A cross-sectional study performed identified LVA in 18.8% of the chronic chagasic patients (CCP)., Objective: Determine the risk of death of patients with chronic chagasic cardiopathy (CCC) and LVA in 24-year interval., Material and Methods: In 1995 a cohort of 298 CCP was evaluated by anamnesis, physical examination, EKG and ECHO and classified in groups: G0 = 86 without cardiopathy; G1 = 156 with cardiopathy without LVA and G2 = 56 with cardiopathy and LVA. 38 patients of G0 and G1 used benznidazole. Information about the deaths was obtained in the notary, death certificates, hospital records and family members., Findings: Were registered 113 deaths (37.9%): 107 (35.9%) attributed to cardiopathy and 6 (2.0%) to other causes (p < 0.05). Amongst these 107 deaths, 10 (11.6%) occurred in G0; 49 (31.4%) occurred in G1 and 48 (85.7%) occurred in G2 (p < 0.05). The risk of death was 2.7 and 7.4 times significantly higher in G2, than in G1 and G0, respectively., Conclusion: Chronic chagasic patients with LVA and ejection fraction < 45% have a higher risk of death than those without.

Background Risk stratification of Chagas disease patients in the limited-resource setting would be helpful in crafting management strategies. We developed a score to predict 2-year mortality in patients with Chagas cardiomyopathy from remote endemic areas. Methods and Results This study enrolled 1551 patients with Chagas cardiomyopathy from Minas Gerais State, Brazil, from the SaMi-Trop cohort (The São Paulo-Minas Gerais Tropical Medicine Research Center). Clinical evaluation, ECG, and NT-proBNP (N-terminal pro-B-type natriuretic peptide) were performed. A Cox proportional hazards model was used to develop a prediction model based on the key predictors. The end point was all-cause mortality. The patients were classified into 3 risk categories at baseline (low, <2%; intermediate, ≥2% to 10%; high, ≥10%). External validation was performed by applying the score to an independent population with Chagas disease. After 2 years of follow-up, 110 patients died, with an overall mortality rate of 3.505 deaths per 100 person-years. Based on the nomogram, the independent predictors of mortality were assigned points: age (10 points per decade), New York Heart Association functional class higher than I (15 points), heart rate ≥80 beats/min (20 points), QRS duration ≥150 ms (15 points), and abnormal NT-proBNP adjusted by age (55 points). The observed mortality rates in the low-, intermediate-, and high-risk groups were 0%, 3.6%, and 32.7%, respectively, in the derivation cohort and 3.2%, 8.7%, and 19.1%, respectively, in the validation cohort. The discrimination of the score was good in the development cohort (C statistic: 0.82), and validation cohort (C statistic: 0.71). Conclusions In a large population of patients with Chagas cardiomyopathy, a combination of risk factors accurately predicted early mortality. This helpful simple score could be used in remote areas with limited technological resources.

Background: Cardiac resynchronization therapy (CRT) is a therapeutic modality for patients with heart failure (HF). The effectiveness of this treatment for event reduction is based on clinical trials where the population of patients with Chagas' disease (DC) is underrepresented., Objective: To evaluate the prognosis after CRT of a population in which CD is an endemic cause of HF., Methods: A retrospective cohort conducted between January 2015 and December 2016 that included patients with HF and left ventricular ejection fraction (LVEF) of less than 35% and undergoing CRT. Clinical and demographic data were collected to search for predictors for the combined outcome of death or hospitalization for HF at one year after CRT implantation., Results: Fifty-four patients were evaluated, and 13 (24.1%) presented CD as the etiology of HF. The mean LVEF was 26.2± 6.1%, and 36 (66.7%) patients presented functional class III or IV HF. After the mean follow-up of 15 (±6,9) months, 17 (32.1%) patients presented the combined outcome. In the univariate analysis, CD was associated with the combined event when compared to other etiologies of HF, 8 (47%) vs. 9 (13,5%), RR: 3,91 CI: 1,46-10,45, p=0,007, as well as lower values of LVEF. In the multivariate analysis, CD and LVEF remained independent risk factors for the combined outcome., Conclusion: In a population of HF patients undergoing CRT, CD was independently associated with mortality and hospitalization for HF.

Introduction: There are conflicting data regarding the efficacy of implantable cardioverter-defibrillator (ICD) in Chagas disease (CD) patients. This study aims to evaluate the short-term outcome after ICD for secondary prevention, in a population where CD is a prevalent cause of heart failure (HF)., Methods and Results: Consecutive patients with HF and reduced left ventricular ejection fraction (LVEF), who underwent ICD implantation for secondary prevention of SCD. Clinical and demographic data were collected to investigate mortality predictors at 1 year. During the study period, 117 patients underwent ICD implantation, of which 108 were included. The most frequent causes of HF was CD: 52 (48.1%) and ischemic cardiomyopathy: 20 (18.5%). Chagas and non-Chagas patients were well balanced-male: 32 (61.5%) vs 38 (67.9%), P = .548; age: 59.2 (±10.9) vs 56.8 (±13.4), P = .681; and LVEF: 34.1 (±0.2) vs 31.3 (±8.7), P = .064, respectively. At the mean follow-up of 15.7 months, overall mortality occurred in 14 (12.9%) patients, with a higher incidence in patients with CD cardiomyopathy, 11 (21.2%) vs 3 (5.4%), P = .021 (log-rank). In the multivariate analysis, CD remained as an independent predictor for death (hazard ratio: 4.62, confidence interval [95% CI]: 1.27-16.81, P = .021)., Conclusion: CD was associated with a poor short-term outcome in patients with HF submitted to ICD implantation for secondary prevention when compared with other HF etiologies. In this specific HF population, ICD indication should be individualized, considering the worst prognosis of these patients., (© 2019 Wiley Periodicals, Inc.)

Introduction: Chagas disease is one of the most relevant endemic parasitic diseases in Latin America, affecting approximately 6 million people. Overt Chagas heart disease is an ominous condition, occurring in 20-30% of infected individuals, which has besides the persistent myocarditis a peculiar intracardiac ganglionic neuronal depletion and dysautonomy. This study aims to evaluate the safety and feasibility of renal denervation for patients with advanced symptomatic Chagas cardiomyopathy., Methods: Open-label prospective pilot study that randomized patients with Chagas heart disease to either renal denervation or conservative treatment (2:1 ratio). The primary endpoint was the incidence of major adverse events at 9 months, defined as a composite of all-cause death, myocardial infarction, stroke, need for renal artery invasive treatment, or worsening renal function., Results: A total of 17 patients were allocated for renal denervation (n = 11) or conservative treatment (n = 6). Included patients had severe symptomatic heart disease, with markedly depressed left ventricular function (average ejection fraction 26.7 ± 4.9%). For patients randomized to renal denervation, the procedure was performed successfully and uneventfully. After 9 months, the primary endpoint occurred in 36.4% of patients in the renal denervation group and 50.0% in the control arm (p = .6). After 9 months, clinical, laboratory, functional, echocardiographic, and quality of life parameters were similar between groups., Conclusions: This pilot study suggests that renal denervation is safe and feasible in patients with Chagas cardiomyopathy, warranting future studies to better evaluate the clinical efficacy of the interventional strategy in improving the prognosis of this high-risk population., (© 2019 Wiley Periodicals, Inc.)

Background: Chagas cardiomyopathy (CDC) is associated with a poor prognosis compared to other cardiomyopathies. Speckle tracking echocardiography (STE), which provides direct assessment of myocardial fiber deformation, may be useful in predicting prognosis., Objective: This study assessed STE in CDC and compared with idiopathic cardiomyopathy (IDC), and also examined the incremental prognostic information of STE over left ventricular ejection fraction (LVEF) in these patients., Methods: We enrolled 112 patients, age of 56.7 ± 11.8 years, 81 with CDC and 31 with IDC. STE indices were obtained at baseline in all patients. The endpoint was a composite of death, hospitalization for heart failure, or need for heart transplantation., Results: Patients with IDC had worse LV systolic function compared to CDC, with LVEF of 34.5% vs 41.3%, p = 0.004, respectively. After adjustment for LVEF, there were no differences in STE values between CDC and IDC. During a median follow-up of 18.2 months (range, 11 to 22), 26 patients met the composite end point (24%). LV longitudinal strain was a strong predictor of adverse events, incremental to LVEF and E/e' ratio (HR 1.463, 95% CI 1.130-1.894; p = 0.004). The risk of cardiac events increased significantly in patients with GLS > - 12% (log-rank p = 0.035)., Conclusions: STE indices were abnormal in patients with dilated cardiomyopathy, without differences between CDC and IDC. LV longitudinal strain was a powerful predictor of outcome, adding prognostic information beyond that provided by LVEF and E/e' ratio., Competing Interests: The authors have declared that no competing interests exist.

Aims: Data on long-term follow-up of patients with Chagas' heart disease (ChHD) receiving a secondary prevention implantable cardioverter-defibrillator (ICD) are limited and its benefit is controversial. The aim of this study was to evaluate the long-term outcomes of ChHD patients who received a secondary prevention ICD., Methods and Results: We assessed the outcomes of consecutive ChHD patients referred to our Institution from 2006 to 2014 for a secondary prevention ICD [89 patients; 58 men; mean age 56 ± 11 years; left ventricular ejection fraction (LVEF), 42 ± 12%]. The primary outcome included a composite of death from any cause or heart transplantation. After a mean follow-up of 59 ± 27 months, the primary outcome occurred in 23 patients (5.3% per year). Multivariate analysis showed that LVEF < 35% [hazard ratio (HR) 4.64; P < 0.01] and age ≥ 65 years (HR 3.19; P < 0.01) were independent predictors of the primary outcome. Using these two risk factors, a risk score was developed, and lower- (no risk factors), intermediate- (one risk factor), and higher-risk (two risk factors) groups were recognized with an annual rate of primary outcome of 1.4%, 7.4%, and 20.4%, respectively. A high burden of appropriate ICD therapies (16% per year) and electrical storms were documented, however, ICD interventions did not impact on the primary outcome., Conclusion: Among ChHD patients receiving a secondary prevention ICD, older age (≥65 years) and left ventricular dysfunction (LVEF < 35%) portend a poor outcome and were associated with increased risk of death or heart transplantation. Most patients received appropriate ICD therapies, however, ICD interventions did not impact on the primary outcome., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: journals.permissions@oup.com.)

American trypanosomiasis is caused by a parasite endemic of the Americas. Current migration has globalized Chagas disease. Acute infection usually resolves spontaneously. Nonetheless, 20% to 40% develop cardiomyopathy 20 to 30 years later. Progression to cardiomyopathy is devastatingly rapid, manifesting with heart failure and sudden death. Etiologic treatment is highly effective and recommended in those with acute infections, congenital infections, and parasite reactivation, and women of childbearing age, but in asymptomatic Trypanosoma cruzi carriers and patients with early cardiomyopathy remains controversial and under investigation. Progression of heart failure is rapid and accounts for most of the morbidity and related mortality., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Myocardial fibrosis (MF) according to cardiac magnetic resonance (CMR) is a frequent finding in Chagas cardiomyopathy and has been associated with risk factors of poor outcome., Objectives: The goal of this study was to determine the prognostic value of MF in predicting combined hard events or all-cause mortality., Methods: Patients with Chagas cardiomyopathy who had a previous CMR evaluation were included, and clinical follow-up was retrospectively obtained. The primary outcome was a combination of all-cause mortality, heart transplantation, antitachycardia pacing or appropriate shock from an implantable cardioverter-defibrillator, and aborted sudden cardiac death; the secondary outcome was all-cause mortality., Results: A total of 130 patients were included; mean age was 53.6 ± 11.5 years, and 53.9% were female. The majority of patients reported no symptoms of heart failure or arrhythmia, but electrocardiographic and echocardiographic abnormalities were common. On CMR, left ventricular dilatation and dysfunction were frequent, and MF was found in 76.1%, with a mean mass of 15.2 ± 16.5 g. Over a median follow-up of 5.05 years, 58 (44.6%) patients reached the combined endpoint, and 45 (34.6%) patients died. MF was associated with the primary outcome as a continuous variable (adjusted hazard ratio: 1.031; 95% CI: 1.013 to 1.049; p = 0.001) and as a categorical variable (MF ≥12.3 g) (adjusted hazard ratio: 2.107; 95% CI: 1.111 to 3.994; p = 0.022), independently from the Rassi risk score. MF expressed as a continuous variable was also associated with all-cause mortality (adjusted hazard ratio: 1.028; 95% CI: 1.005 to 1.051; p = 0.017) independently from the Rassi risk score., Conclusions: MF is an independent predictor of adverse outcome in Chagas cardiomyopathy. Our data may support the use of CMR in better risk-stratifying this population and possibly guiding therapy., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Patients with chronic Chagas cardiomyopathy (CCC) have pronounced myocardial fibrosis, which may predispose to sudden cardiac death, despite well-preserved global left ventricular (LV) systolic function. Cardiac magnetic resonance can assess myocardial fibrosis by late gadolinium enhancement (LGE) sequences., Objectives: This prospective study evaluated if the presence of scar by LGE predicted hard adverse outcomes in a cohort of patients with CCC., Methods: A prospective cohort of 140 patients with CCC (52.1% female; median age 57 years [interquartile range: 45 to 67 years]) were included. Cardiac magnetic resonance cine and LGE imaging were performed at enrollment with a 1.5-T scanner. The primary endpoint was the combination of cardiovascular death and sustained ventricular tachycardia. The secondary endpoint was the combination of cardiovascular death, sustained ventricular tachycardia, or cardiovascular hospitalization during follow-up., Results: After a median of 34 months (interquartile range: 24 to 49 months) of follow-up, 11 cardiovascular deaths, 3 episodes of sustained ventricular tachycardia, and 20 cardiovascular hospitalizations were recorded. LGE scar was present in 71.4% of the patients, with the lateral, inferolateral, and inferior walls most commonly affected. Patients with positive LGE had lower LV ejection fraction and higher LV end-diastolic volume and LV mass than patients without LGE. No difference in other cardiovascular risk factors was noted. Patients with scar had higher event rates compared with those without scar for the primary (p = 0.043) and the secondary (p = 0.016) endpoint. In multivariable analysis, age and LGE area were related to primary outcome; age and lower LV ejection fraction were related to the secondary outcome. The pattern of LGE myocardial fibrosis was transmural, focal, or diffuse scar in approximately one-third of patients with positive LGE, and no pattern was specifically related to outcomes., Conclusions: In patients with CCC, presence of scar by LGE is common and is strongly associated with major adverse outcomes., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: Cardiac resynchronization therapy (CRT) is an established procedure for patients with heart failure. However, trials evaluating its efficacy did not include patients with chronic Chagas cardiomyopathy (CCC). We aimed to assess the role of CRT in a cohort of patients with CCC., Methods and Results: This retrospective study compared the outcomes of CCC patients who underwent CRT with those of dilated (DCM) and ischaemic cardiomyopathies (ICM). The primary endpoint was all-cause mortality and the secondary endpoints were the rate of non-advanced New York Heart Association (NYHA) class 12 months after CRT and echocardiographic changes evaluated at least 6 months after CRT. There were 115 patients in the CCC group, 177 with DCM, and 134 with ICM. The annual mortality rates were 25.4%, 10.4%, and 11.3%, respectively (P < 0.001). Multivariate analysis adjusted for potential confounders showed that the CCC group had a two-fold [hazard ratio 2.34 (1.47-3.71), P < 0.001] higher risk of death compared to the DCM group. The rate of non-advanced NYHA class 12 months after CRT was significantly higher in non-CCC groups than in the CCC group (DCM 74.0% vs. ICM 73.9% vs. 56.5%, P < 0.001). Chronic Chagas cardiomyopathy and ICM patients had no improvement in the echocardiographic evaluation, but patients in the DCM group had an increase in left ventricular ejection fraction and a decrease in left ventricular end-diastolic diameter., Conclusion: This study showed that CCC patients submitted to CRT have worse prognosis compared to patients with DCM and ICM who undergo CRT. Studies comparing CCC patients with and without CRT are warranted.

Background: The risk of thromboembolic events is increased in patients with heart failure (HF); however, few studies have reported thromboembolic findings in HF patients who have undergone autopsy., Methods and Results: We reviewed 1457 autopsies (January 2000/July 2006) and selected 595 patients with HF. We studied the occurrence of thromboembolic events in patients' autopsy reports. Mean age was 61.8±15.9 years; 376 (63.2%) were men and 219 (36.8%) women; left ventricular ejection fraction was 42.1±18.7%. HF etiologies were coronary artery disease in 235 (39.5%) patients, valvular disease in 121 (20.3%), and Chagas' disease in 81 (13.6%). The main cause of death was progressive HF in 253 (42.5%) patients, infections in 112 (18.8%), myocardial infarction in 86 (14.5%), and pulmonary embolism in 81 (13.6%). Altogether, 233 patients (39.2%) suffered 374 thromboembolic events. A thromboembolic event was considered the direct cause of death in 93 (24.9%) patients and related to death in 158 (42.2%). The most frequent thromboembolism was pulmonary embolism in 135 (36.1%) patients; in 81 events (60%), it was considered the cause of death. When we compared clinical characteristics of patients, sex (OR=1.511, CI 95% 1.066-2.143, P=.021) and Chagas disease (OR=2.362, CI 95% 1.424-3.918, P=.001) were independently associated with the occurrence of thromboembolisms., Conclusions: Thromboembolic events are frequent in patients with heart failure revealed at autopsy, and are frequently associated with the death process. Our findings warrant a high degree of suspicion for these occurrences, especially during the care of more susceptible populations, such as women and Chagas patients., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Chagas heart disease (CHD) is a dilated cardiomyopathy characterized by malignant ventricular arrhythmias and increased risk of sudden cardiac death (SCD). Much controversy exists concerning the efficacy of implantable cardioverter-defibrillator (ICDs) in CHD because of mixed results observed. We report our long-term experience with ICDs for secondary prevention in CHD, with the specific aim of assessing the results in groups with preserved or depressed global left ventricular function., Methods: 111 patients (75 males; 60 ± 12 years) were followed for 1,948 ± 1,275 days after ICD. Time to death was the primary outcome; LVEF ≤ 45% the exposure; and age, gender, and ICD therapy delivery the potential confounders. We used time-to-event methods and Cox proportional models for analysis, censoring observations at time of death or at 5-year follow-up in survivors., Results: Seventy-two percent of the patients presented at least one sustained ventricular arrhythmia requiring appropriate therapy, and only three patients received inappropriate therapy. Death occurred in 50 (45%) patients, with an annual mortality rate of 8.4%, mostly due to refractory heart failure or noncardiac causes. Unadjusted survival rates were significantly distinct between patients with left ventricular ejection fraction (LVEF) ≤ 45% (26 deaths), 50.5% (95% confidence interval [CI]: 36.2%-63.2%) when compared to patients with LVEF > 45% (10 deaths), 77.6% (95% CI: 62.3%-87.3%, P < 0.01). After adjusting for confounders, low LVEF (hazard ratio [HR]: 5.2, 95% CI: 2.3-11.6), age (HR: 1.04, 95% CI: 1.01-1.07), and female gender (HR: 3.97, 95% CI: 1.85-8.54) were independently associated with the outcome., Conclusions: ICDs successfully aborted life-threatening arrhythmias in CHD patients. Impaired left ventricular function predicted higher mortality in CHD patients with an ICD for secondary prevention of SCD., (© 2018 Wiley Periodicals, Inc.)

Background: It has been difficult to prove that "catecholamine-induced cardiomyopathy" contributes to the mechanism of sudden cardiac death in Chagas heart disease. Also, it is almost impossible to rule out the possibility that it is not involved in the process. More importantly, the vagal-cholinergic pathway in the ventricle plays a direct role in the prevention of the initiation of complex ventricular arrhythmias, including nonsustained ventricular tachycardia, ventricular fibrillation responsible for sudden death., Objective: To determine frequency of parasympathetic autonomic indices among the different groups of risk of cardiovascular death when stratified by Rassi score., Methods: Patients with Chagas heart disease were selected and divided into three risk groups by Rassi score. A fourth group, non-Chagas group, was of similar age and gender. All were subjected to analysis of heart rate variability during controlled breathing (RSA) and tilt table passive test (tilt test). High frequency and low frequency/high frequency ratio were calculated and presented by box-plot. Also, t-test was used to compare the two groups., Results: It was observed that the parasympathetic and sympathetic component were affected, when the risk group increased the response was worsened to the stimulus (RSA or Tilt). Also, the low-risk group was jeopardized, when compared to the non-Chagas group., Conclusion: The loss of parasympathetic modulation was present in all Rassi risk groups, including the low risk, indicating that a morphological change of the myocardium represents a detectable neurofunctional change., (© 2018 Wiley Periodicals, Inc.)

Aims: Explore the association between clinical findings and prognosis in patients with acute decompensated heart failure (ADHF) and analyze the influence of etiology on clinical presentation and prognosis., Methods and Results: Prospective cohort of 500 patients admitted with ADHF from Aug/2013-Feb/2016; patients were predominantly male (61.8%), median age was 58 (IQ25-75% 47-66 years); etiology was dilated cardiomyopathy in 141 (28.2%), ischemic heart disease in 137 (27.4%), and Chagas heart disease in 113 (22.6%). Patients who died (154 [30.8%]) or underwent heart transplantation (53[10.6%]) were younger (56 years [IQ25-75% 45-64 vs 60 years, IQ25-75% 49-67], P = 0.032), more frequently admitted for cardiogenic shock (20.3% vs 6.8%, P<0.001), had longer duration of symptoms (14 days [IQ25-75% 4-32.8 vs 7.5 days, IQ25-75% 2-31], P = 0.004), had signs of congestion (90.8% vs 76.5%, P<0.001) and inadequate perfusion more frequently (45.9% vs 28%, P<0.001), and had lower blood pressure (90 [IQ25-75% 80-100 vs 100, IQ25-75% 90-120], P<0.001). In a logistic regression model analysis, systolic blood pressure (P<0.001, OR 0.97 [95%CI 0.96-0.98] per mmHg) and jugular distention (P = 0.004, OR 1.923 [95%CI 1.232-3.001]) were significant. Chagas patients were more frequently admitted for cardiogenic shock (15%) and syncope/arrhythmia (20.4%). Pulmonary congestion was rare among Chagas patients and blood pressure was lower. The rate of in-hospital death or heart transplant was higher among patients with Chagas (50.5%)., Conclusions: A physical exam may identify patients at higher risk in a contemporaneous population. Our findings support specific therapies targeted at Chagas patients in the setting of ADHF.

We sought to investigate the prognostic value of the electrocardiogram (ECG) electrical axes (P wave, T wave and QRS) as predictors of mortality in the 14-year follow-up of the prospective cohort of all residents ≥60 years living in the southeastern Brazilian city of Bambuí, a population with high prevalence of Chagas disease (ChD). Baseline ECG axes were automatically measured with normal values defined as follows: P-wave axis 0° to 75°, QRS axis -30° to 90°, and T axis 15° to 75°. Participants underwent annual follow-up visits and death was verified using death certificates. Cox proportional hazards regression was used to assess the prognostic value of ECG axes for all-cause mortality, after adjustment for potential confounders. From 1,742 qualifying residents, 1,462 were enrolled, of whom 557 (38.1%) had ChD. Mortality rate was 51.9%. In multivariable adjusted models, abnormal P-wave axis was associated with a 48% (hazard ratio [HR] = 1.48 [95% confidence interval (CI) 1.16-1.88]) increased mortality risk in patients with ChD and 43% (HR = 1.43 [CI 1.13-1.81]) in patients without ChD. Abnormal QRS axis was associated with a 34% (HR = 1.34 [CI 1.04-1.73]) increased mortality risk in patients with ChD, but not in individuals without ChD. Similarly, in the ChD group, abnormal T-wave axis was associated with a 35% (HR = 1.35 [CI 1.07-1.71]) increased mortality, but not in patients without ChD. In conclusion, abnormal P-wave, QRS, and T-wave axes were associated with increased all-cause mortality in patients with ChD. Abnormal P-wave axis was associated with mortality also among those without ChD, being the strongest predictor among ECG variables., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Introduction: Chagas disease represents an important health problem with socioeconomic impacts in many Latin-American countries. It is estimated that 20% to 30% of the people infected by Trypanosoma cruzi will develop chronic Chagas cardiomyopathy (CCC), which is generally accompanied by heart failure (HF). Cardiac resynchronization therapy (CRT) may be indicated for patients with HF and electromechanical dysfunctions., Objective: The primary endpoint of this study was to analyze the response to CRT in patients with CCC, while the secondary endpoint was to estimate the survival rates of CRT responder patients., Methods: This is an observational, cross-sectional and retrospective study. The records of 50 patients with CRT pacing devices implanted between June 2009 and March 2017 were analyzed. For statistical analyses, Pearson's correlation was used along with Student's t-test, and survival was analyzed using the Kaplan-Meier method. A P value of <0.05 was considered significant., Results: Out of 50 patients, 56% were male, with a mean age of 63.4±13.3 years and an average CRT duration of 61.2±21.7 months. The mean QRS duration was 150.12±12.4 ms before and 116.04±2.2 ms after the therapy (P<0.001). The mean left ventricular ejection fractions (LVEF) were 29±7% and 39.1±12.2% before and after CRT, respectively (P<0.001). A total of 35 (70%) patients had a reduction of at least one New York Heart Association (NYHA) functional class after six months of therapy (P=0.014). The survival rate after 72 months was 45%., Conclusion: This study showed clinical improvement and a nonsignificant survival rate in patients with CCC after the use of CRT.

Background: Chronic Chagas cardiomyopathy (CCC) is the most serious and frequent manifestation of Chagas disease. Conduction abnormalities and bradycardia requiring pacemaker are common. The aim of this study was to determine the rate and predictors of death in CCC patients with pacemaker., Methods: In this single-center prospective cohort study we assessed the outcome of 396 CCC patients with pacemaker, followed-up for at least 24months. All patients underwent a clinical and device assessment, 12-lead electrocardiography and echocardiography., Results: During the median follow-up of 1.9years (Interquartile range 1.6-2.4), there were 65 (16.4%) deaths, yielding an annual mortality rate of 8.6%. The major cause was sudden death (33.8%), followed by heart failure (HF), 32.3%. All the investigated variables were examined as potential predictors of death. The final multivariate logistic regression model included five independent variables: advanced HF functional class (OR [odds ratio] 6.71; 95% confidence interval [95% CI] 1.95-23.2; P=0.003), renal disease (OR 5.71; 95% CI 1.80-18.0; P=0.003), QRS ≥150ms (OR 2.80; 95% CI 1.08-7.27; P=0.034), left atrial enlargement (OR 2.75; 95% CI 1.09-6.95; P=0.032) and left ventricular ejection fraction ≤43% (OR 2.31; 95% CI 1.07-4.97; P=0.032). The model had good discrimination, confirmed by bootstrap validation (optimism-adjusted c-statistic of 0.78) and the calibration curve showed a proper calibration (slope=0.972)., Conclusions: CCC patients with pacemaker have a high annual mortality rate despite that the pacemaker related variables were not predictors of death. The independent predictors of death can help us to identify the poor prognosis patients., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Anaerobic threshold (AT) is recognized as objective and direct measurement that reflects variations in metabolism of skeletal muscles during exercise. Its prognostic value in heart diseases of non-chagasic etiology is well established. However, the assessment of risk of death in Chagas heart disease is relatively well established by Rassi score. But, the added value that AT can bring to Rassi score has not been studied yet., Objectives: To assess whether AT presents additional effect to Rassi score in patients with chronic Chagas' heart disease., Methods: Prospective research of dynamic cohort by review of 150 medical records of patients. Were selected for cohort 45 medical records of patients who underwent cardiopulmonary exercise testing between 1996-1997 and followed until September 2015. Data analysis to detect association between studied variables can be seen using a logistic regression model. The suitability of the models was verified using ROC curves and the coefficient of determination R 2 ., Results: 8 patients (17.78%) died by September 2015, with 7 of them (87.5%) from cardiovascular causes, of which 4 (57.14%) were considered on high risk by Rassi score. With Rassi score as independent variable, and death being the outcome, we obtained an area under the curve (AUC)=0.711, with R 2 =0.214. Instituting AT as independent variable, we found AUC=0.706, with R 2 =0.078. When we define Rassi score and AT as independent variables, it was obtained AUC=0.800 and R 2 =0.263., Conclusion: when AT is included in logistic regression, it increases by 5% the explanation (R 2 ) to the death estimation., (Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background: Chagas' disease is an important cause of cardiomyopathy in Latin America. We aimed to compare clinical characteristics and outcomes in patients with heart failure (HF) with reduced ejection fraction caused by Chagas' disease, with other etiologies, in the era of modern HF therapies., Methods and Results: This study included 2552 Latin American patients randomized in the PARADIGM-HF (Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) and ATMOSPHERE (Aliskiren Trial to Minimize Outcomes in Patients With Heart Failure) trials. The investigator-reported etiology was categorized as Chagasic, other nonischemic, or ischemic cardiomyopathy. The outcomes of interest included the composite of cardiovascular death or HF hospitalization and its components and death from any cause. Unadjusted and adjusted Cox proportional hazards models were performed to compare outcomes by pathogenesis. There were 195 patients with Chagasic HF with reduced ejection fraction, 1300 with other nonischemic cardiomyopathy, and 1057 with ischemic cardiomyopathy. Compared with other etiologies, Chagasic patients were more often female, younger, and had lower prevalence of hypertension, diabetes mellitus, and renal impairment (but had higher prevalence of stroke and pacemaker implantation) and had worse health-related quality of life. The rates of the composite outcome were 17.2, 12.5, and 11.4 per 100 person-years for Chagasic, other nonischemic, and ischemic patients, respectively-adjusted hazard ratio for Chagasic versus other nonischemic: 1.49 (95% confidence interval, 1.15-1.94; P =0.003) and Chagasic versus ischemic: 1.55 (1.18-2.04; P =0.002). The rates of all-cause mortality were also higher., Conclusions: Despite younger age, less comorbidity, and comprehensive use of conventional HF therapies, patients with Chagasic HF with reduced ejection fraction continue to have worse quality of life and higher hospitalization and mortality rates compared with other etiologies., Clinical Trial Registration: PARADIGM-HF: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01035255; ATMOSPHERE: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00853658., (© 2017 American Heart Association, Inc.)

Background: Prognostic factors are extensively studied in heart failure; however, their role in severe Chagasic heart failure have not been established., Objectives: To identify the association of clinical and laboratory factors with the prognosis of severe Chagasic heart failure, as well as the association of these factors with mortality and survival in a 7.5-year follow-up., Methods: 60 patients with severe Chagasic heart failure were evaluated regarding the following variables: age, blood pressure, ejection fraction, serum sodium, creatinine, 6-minute walk test, non-sustained ventricular tachycardia, QRS width, indexed left atrial volume, and functional class., Results: 53 (88.3%) patients died during follow-up, and 7 (11.7%) remained alive. Cumulative overall survival probability was approximately 11%. Non-sustained ventricular tachycardia (HR = 2.11; 95% CI: 1.04 - 4.31; p<0.05) and indexed left atrial volume ≥ 72 mL/m2 (HR = 3.51; 95% CI: 1.63 - 7.52; p<0.05) were the only variables that remained as independent predictors of mortality., Conclusions: The presence of non-sustained ventricular tachycardia on Holter and indexed left atrial volume > 72 mL/m2 are independent predictors of mortality in severe Chagasic heart failure, with cumulative survival probability of only 11% in 7.5 years.

Current treatments for chronic Chagas cardiomyopathy, a disease with high mortality rates and caused by the protozoan Trypanosoma cruzi , are unsatisfactory. Myocardial inflammation, including endothelial activation, is responsible for the structural and functional damage seen in the chronic phase. The clinical efficacy of benznidazole could be improved by decreasing chronic inflammation. Statins, which have anti-inflammatory properties, may improve the action of benznidazole. Here, the action of simvastatin in a murine model of chronic Chagas cardiomyopathy and the link with the production of the proresolving eicosanoid 15-epi-lipoxin A4, produced by 5-lipoxygenase, are evaluated. Simvastatin decreased the expression of the adhesion molecules E-selectin, intracellular adhesion molecule type 1 (ICAM-1), and vascular cell adhesion molecule type 1 (VCAM-1) in T. cruzi -infected mice. However, when this drug was administered to 5-lipoxygenase-deficient mice, the anti-inflammatory effect was not observed unless exogenous 15-epi-lipoxin A4 was administered. Thus, in chronic Chagas disease, 5-epi-lipoxin A4 induced by simvastatin treatment could improve the pathophysiological condition of patients by increasing the trypanocidal action of benznidazole., (Copyright © 2017 American Society for Microbiology.)

Background/objectives: Up 30 to 40% of Chagas patients exhibit cardiomyopathy with different degrees of cardiac involvement. Biomarkers may help in differentiation of the severity of Chagas cardiomyopathy (CCM). This study sought to examine the diagnostic value of a panel of biomarkers to distinguish the severity of (CCM)., Methods: 100 patients with CCM were included in this cross-sectional study. Based on electrocardiogram and echocardiogram, CCM patients were classified in three stages according to disease's severity. Levels of high-sensitivity cardiac troponin T (Hs-cTnT), N-terminal pro B-type natriuretic peptide (NT-proBNP), galectin-3 (Gal-3), neutrophil gelatinase-associated lipocalin (NGAL), soluble ST2 (sST2) and cystatin-c (Cys-c) were measured. Logistic regression models were used to assess the association between levels of natural log-transformed values of biomarkers and stages C/D versus B. We also calculated the area under curve (AUC) for each of the models., Results: In models adjusted for age, sex, body mass index, kidney function and medication use, increased levels of NT-proBNP (per 1 unit natural log-transformed values, odds ratio (OR)=5.55; 95CI%:1.65-18.72) and Hs-cTnT (per 1 unit natural log-transformed values, OR=7.11; 95CI%:1.41-35.90) showed significant association with the severity of CCM per 1 unit increase of biomarkers. The accuracy of NT-proBNP and Hs-cTnT for diagnosis of the severity of CCM was high: AUC of 0.968 and 0.956 respectively. No significant difference was found in the AUC between NT-proBNP and Hs-cTnT. No association was found between Gal-3, NGAL, sST2 and Cys-C and severity of CCM., Conclusions: NT-proBNP and Hs-cTnT have both same diagnostic value in distinguishing severity of CCM., (Copyright © 2016. Published by Elsevier Ireland Ltd.)

Chagasic cardiomyopathy, which is seen in Chagas disease, is the most severe and life-threatening manifestation of infection by the kinetoplastid Trypanosoma cruzi. Adipose tissue and diet play a major role in maintaining lipid homeostasis and regulating cardiac pathogenesis during the development of Chagas cardiomyopathy. We have previously reported that T. cruzi has a high affinity for lipoproteins and that the invasion rate of this parasite increases in the presence of cholesterol, suggesting that drugs that inhibit cholesterol synthesis, such as statins, could affect infection and the development of Chagasic cardiomyopathy. The dual epidemic of diabetes and obesity in Latin America, the endemic regions for Chagas disease, has led to many patients in the endemic region of infection having hyperlipidemia that is being treated with statins such as atorvastatin. The current study was performed to examine mice fed on either regular or high fat diet for effects of atorvastatin on T. cruzi infection-induced myocarditis and to evaluate the effect of this treatment during infection on adipose tissue physiology and cardiac pathology. Atorvastatin was found to regulate lipolysis and cardiac lipidopathy during acute T. cruzi infection in mice and to enhance tissue parasite load, cardiac LDL levels, inflammation, and mortality in during acute infection. Overall, these data suggest that statins, such as atorvastatin, have deleterious effects during acute Chagas disease., (Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Background: The outcome of Chagas disease patients after receiving implantable cardioverter defibrillator (ICD) is still controversial., Objective: To compare clinical outcomes after ICD implantation in patients with chronic Chagas cardiomyopathy (CCC) and ischemic heart disease (IHD)., Methods: Prospective study of a population of 153 patients receiving ICD (65 with CCC and 88 with IHD). The devices were implanted between 2003 and 2011. Survival rates and event-free survival were compared., Results: The groups were similar regarding sex, functional class and ejection fraction. Ischemic patients were, on average, 10 years older than CCC patients (p < 0.05). Patients with CCC had lower schooling and monthly income than IHD patients (p < 0.05). The number of appropriate therapies was 2.07 higher in CCC patients, who had a greater incidence of appropriate shock (p < 0.05). Annual mortality rate and electrical storm incidence were similar in both groups. There was no sudden death in CCC patients, and only one in IHD patients. Neither survival time (p = 0.720) nor event-free survival (p = 0.143) significantly differed between the groups., Conclusion: CCC doubles the risk of receiving appropriate therapies as compared to IHD, showing the greater complexity of arrhythmias in Chagas patients., Competing Interests: Potential Conflict of Interest No potential conflict of interest relevant to this article was reported.

This paper introduces a technique for predicting death in patients with Chagas disease using features extracted from symbolic series and time-frequency indices of heart rate variability (HRV). The study included 150 patients: 15 patients who died and 135 who did not. The HRV series were obtained from 24-h Holter monitoring. Sequences of symbols from 5-min epochs from series of RR intervals were generated using symbolic dynamics and ordinal pattern statistics. Fourteen features were extracted from symbolic series and four derived from clinical aspects of patients. For classification, the 18 features from each epoch were used as inputs in a support vector machine (SVM) with a radial basis function (RBF) kernel. The results showed that it is possible to distinguish between the two classes, patients with Chagas disease who did or did not die, with a 95% accuracy rate. Therefore, we suggest that the use of new features based on symbolic series, coupled with classic time-frequency and clinical indices, proves to be a good predictor of death in patients with Chagas disease., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: The role of trypanocidal therapy in patients with established Chagas' cardiomyopathy is unproven., Methods: We conducted a prospective, multicenter, randomized study involving 2854 patients with Chagas' cardiomyopathy who received benznidazole or placebo for up to 80 days and were followed for a mean of 5.4 years. The primary outcome in the time-to-event analysis was the first event of any of the components of the composite outcome of death, resuscitated cardiac arrest, sustained ventricular tachycardia, insertion of a pacemaker or implantable cardioverter-defibrillator, cardiac transplantation, new heart failure, stroke, or other thromboembolic event., Results: The primary outcome occurred in 394 patients (27.5%) in the benznidazole group and in 414 (29.1%) in the placebo group (hazard ratio, 0.93; 95% confidence interval [CI], 0.81 to 1.07; P=0.31). At baseline, a polymerase-chain-reaction (PCR) assay was performed on blood samples obtained from 1896 patients; 60.5% had positive results for Trypanosoma cruzi on PCR. The rates of conversion to negative PCR results (PCR conversion) were 66.2% in the benznidazole group and 33.5% in the placebo group at the end of treatment, 55.4% and 35.3%, respectively, at 2 years, and 46.7% and 33.1%, respectively, at 5 years or more (P<0.001 for all comparisons). The effect of treatment on PCR conversion varied according to geographic region: in Brazil, the odds ratio for PCR conversion was 3.03 (95% CI, 2.12 to 4.34) at 2 years and 1.87 (95% CI, 1.33 to 2.63) at 5 or more years; in Colombia and El Salvador, the odds ratio was 1.33 (95% CI, 0.90 to 1.98) at 2 years and 0.96 (95% CI, 0.63 to 1.45) at 5 or more years; and in Argentina and Bolivia, the odds ratio was 2.63 (95% CI, 1.89 to 3.66) at 2 years and 2.79 (95% CI, 1.99 to 3.92) at 5 or more years (P<0.001 for interaction). However, the rates of PCR conversion did not correspond to effects on clinical outcome (P=0.16 for interaction)., Conclusions: Trypanocidal therapy with benznidazole in patients with established Chagas' cardiomyopathy significantly reduced serum parasite detection but did not significantly reduce cardiac clinical deterioration through 5 years of follow-up. (Funded by the Population Health Research Institute and others; ClinicalTrials.gov number, NCT00123916; Current Controlled Trials number, ISRCTN13967269.).

Background: Chagas cardiomyopathy is a chronic sequela of infection by the parasite, Trypanosoma cruzi. Advanced cardiomyopathy is associated with a high mortality rate, and clinical characteristics have been used to predict mortality risk. Though multiple biomarkers have been associated with Chagas cardiomyopathy, it is unknown how these are related to survival., Objectives: This study aimed to identify biomarkers associated with mortality in individuals with severe Chagas cardiomyopathy in an urban Bolivian hospital., Methods: The population included individuals with and without T. cruzi infection recruited in an urban hospital in Santa Cruz, Bolivia. Baseline characteristics, electrocardiogram findings, medications, and serum cardiac biomarker levels (B-type natriuretic peptide [BNP], N-terminal pro-B-type natriuretic peptide [NT-proBNP], creatine kinase-myocardial band [CK-MB], troponin I, matrix metalloproteinase [MMP]-2, MMP-9, tissue inhibitor of metalloproteinases [TIMP] 1 and 2, transforming growth factor [TGF] beta 1 and 2) were ascertained. Echocardiograms were performed on those with cardiac symptoms or electrocardiogram abnormalities at baseline. Participants were contacted approximately 1 year after initial evaluation; deaths were reported by family members. Receiver-operating characteristic curves (ROC) were used to optimize cutoff values for each marker. For markers with area under the curve (AUC) >0.55, Cox proportional hazards models were performed to determine the hazards ratio (HR) and 95% confidence interval (CI) for the association of each marker with mortality., Results: The median follow-up time was 14.1 months (interquartile range 12.5, 16.7). Of 254 individuals with complete cardiac data, 220 (87%) had follow-up data. Of 50 patients with severe Chagas cardiomyopathy at baseline, 20 (40%) had died. Higher baseline levels of BNP (HR: 3.1, 95% CI: 1.2 to 8.4), NT-proBNP (HR: 4.4, 95% CI: 1.8 to 11.0), CK-MB (HR: 3.3, 95% CI: 1.3 to 8.0), and MMP-2 (HR: 4.2, 95% CI: 1.5 to 11.8) were significantly associated with subsequent mortality., Conclusions: Severe Chagas cardiomyopathy is associated with high short-term mortality. BNP, NT-proBNP, CK-MB, and MMP-2 have added predictive value for mortality, even in the presence of decreased ejection fraction and other clinical signs of congestive heart failure., (Copyright © 2015 World Heart Federation (Geneva). All rights reserved.)

Background: The efficacy of implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy-defibrillator (CRT-D) therapy has already been established in clinical trials but their effectiveness in several clinical settings remains undetermined. This study aimed to assess the effectiveness of ICD and CRT-D therapies within the Brazilian National Health System (SUS)., Methods: All patients who underwent ICD or CRT-D implantation within the SUS from 2001 to 2007 were included in the study. We compared estimated Kaplan-Meier survival curves using the Peto's test. Prognostic factors were selected using Cox's models., Results: There were included 3,295 patients in the ICD group and 681 patients in the CRT-D group. Cardiac causes accounted for 79% of all deaths in both groups and Chagas' heart disease accounted for 31% of these deaths. In the CRT-D group, survival significantly decreased around the fourth year of follow-up, with a decrease from 59.5% to 38.3% in 5.5 months. Transvenous implantation technique was used in 62% of CRT-D patients. In-hospital case-fatality rates were higher in those undergoing surgical implantation (5.3%) than those undergoing transvenous implantation (1.6%) (p = 0.02)., Conclusions: The results show that short-term, medium-term and long-term effectiveness of ICD therapy appears to be similar to that evidenced in clinical trials. In the CRT-D group, in-hospital case-fatality and 30-day case-fatality were higher than those reported in other studies. Surgical epicardial implantation technique was performed in this group at a higher frequency than that reported in the literature and was associated with poorer short-term prognosis.

The identification of predictors for the progression of chronic Chagas cardiomyopathy (CCC) is essential to ensure adequate patient management. This study looked into a non-concurrent cohort of 165 CCC patients between 1985 and 2010 for independent predictors for CCC progression. The outcomes were worsening of the CCC scores and the onset of left ventricular dysfunction assessed by means of echo-Doppler cardiography. Patients were analyzed for social, demographic, epidemiologic, clinical and workup-related variables. A descriptive analysis was conducted, followed by survival curves based on univariate (Kaplan-Meier and Cox's univariate model) and multivariate (Cox regression model) analysis. Patients were followed from two to 20 years (mean: 8.2). Their mean age was 44.8 years (20-77). Comparing both iterations of the study, in the second there was a statistically significant increase in the PR interval and in the QRS duration, despite a reduction in heart rates (Wilcoxon < 0.01). The predictors for CCC progression in the final regression model were male gender (HR = 2.81), Holter monitoring showing pauses equal to or greater than two seconds (HR = 3.02) increased cardiothoracic ratio (HR = 7.87) and time of use of digitalis (HR = 1.41). Patients with multiple predictive factors require stricter follow-up and treatment.

Background/objectives: Chronic Chagas heart disease (ChHD) is associated with ventricular tachyarrhythmias and an increased risk of sudden cardiac death. Little is known about the effectiveness of implantable cardioverter-defibrillator (ICD) therapy in this population. The objective of this study was to evaluate the efficacy of ICD in patients with ChHD and to identify predictors of mortality and appropriate ICD shocks., Methods: The cohort study included 65 patients with ChHD and ICD for primary and secondary prevention of sudden death. The Cox model was applied to evaluate the predictors of mortality, and survival was assessed by Kaplan-Meier analysis., Results: The median age was 56 ± 11.9 years. The median follow-up was 40 ± 26.8 months. Among the patients 23 (36.5%) had appropriate shocks. A total of 13 (20%) patients died (6.1% of annual mortality rate), and there was no sudden death. In univariate Cox model, functional class IV (hazard ratio [HR] = 1.99; 95% confidence interval [CI], 1.05-3.76; P = 0.034), primary prevention (HR = 0.29; 95% CI, 0.09-0.99; P = 0.048), lower education (HR = 2.51; 95% CI, 1.05-5.99; P = 0.038), and ejection fraction <30% (HR = 2.80; 95% CI, 1.09-7.18; P = 0.032) were predictors of worse prognosis (death). In the multivariate Cox model, an ejection fraction <30% and the low education remained predictors of poor prognosis. Predictors of appropriate shocks were not found., Conclusions: The ICD was effective for the prevention of sudden cardiac death in patients with chronic ChHD. An ejection fraction <30% and low education were predictors of poor prognosis., (©2014, The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals, Inc.)

Diagnosis, prognosis and evaluation of death risk in Chagas cardiomyopathy still constitute a challenge due to the diversity of manifestations, which determine the importance of using echocardiography, tissue Doppler and biomarkers. To evaluate, within a systematic review, clinical and echocardiographic profiles of patients with chronic chagasic cardiomyopathy, which may be related to worse prognosis and major mortality risk. To perform the systematic review, we used Medline (via PubMed), LILACS and SciELO databases to identify 82 articles published from 1991 to 2012, with the following descriptors: echocardiography, mortality and Chagas disease. We selected 31 original articles, involving diagnostic and prognostic methods. The importance of Chagas disease has increased due to its emergence in Europe and United States, but most evidence came from Brazil. Among the predictors of worse prognosis and higher mortality risk are morphological and functional alterations in the left and right ventricles, evaluated by conventional echocardiography and tissue Doppler, as well as the increase in brain natriuretic peptide and troponin I concentrations. Recently, the evaluations of dyssynchrony, dysautonomia, as well as strain, strain rate and myocardial twisting were added to the diagnostic arsenal for the early differentiation of Chagas cardiomyopathy. Developments in imaging and biochemical diagnostic procedures have enabled more detailed cardiac evaluations, which demonstrate the early involvement of both ventricles, allowing a more accurate assessment of the mortality risk in Chagas disease.

Introduction: Chagas disease is a major cause of cardiomyopathy and sudden death in our country. It has a high mortality when their patients develop New York Heart Association (NYHA) class IV., Objective: The objective of this study is to analyze the clinical outcome of patients with Chagas' cardiomyopathy with congestive heart failure with optimized pharmacological therapy, undergoing cardiac resynchronization therapy., Methods: Between January 2004 and February 2009, 72 patients with Chagas' cardiomyopathy in NYHA class III and IV underwent cardiac resynchronization therapy and were monitored to assess their clinical evolution. We used the t test or the Wilcoxon test to compare the same variable in two different times. A P value < 0.05 was established as statistically significant., Results: The average clinical follow-up was 46.6 months (range 4-79 months). At the end of the evaluation, 87.4% of patients were in NYHA class I or II (P<0.001). There was response to therapy in 65.3% of patients (P<0.001), with an overall mortality of 34.7%., Conclusion: In patients with chronic Chagas cardiomyopathy undergoing cardiac resynchronization therapy, we found the following statistically significant changes: improvement in NYHA class and increase of left ventricle ejection fraction, a decrease of the systolic final diameter and systolic final left ventricle volume and improvement of patient survival.

Objectives: We investigated if cardiac spatial repolarization heterogeneity might be associated with an increased risk of death in patients with chronic Chagas disease., Methods: Repolarization heterogeneity was assessed using the V-index, a recently introduced metric founded on a biophysical model of the ECG. This metric provides an estimate of the standard deviation of the repolarization times across the heart. We analyzed 113 patients (aged 21- 67 years) enrolled between 1998 and 1999 who had a known serological status showing positive reactions to Trypanosoma cruzi. Fourteen subjects died during a 10-year follow-up period., Results: The V-index was significantly lower in survivor (S) than in non-survivor (NS) subjects (S: 31.2 ± 13.3 ms vs NS: 41.2 ± 18.6 ms, single-tail t-test: p = 0.009, single-tail Wilcoxon rank sum test: p = 0.029). A V-index larger than 36.3 ms was related to a significantly higher risk of death in a univariate Cox proportional-hazards analysis (hazard ratio, HR = 5.34, p = 0.0046). In addition, V-index > 36.3 ms retained its prognostic value in a multivariate Cox proportional-hazards analysis after adjustment for other three clinical variables (left ventricular ejection factor < 0.50, QRS duration > 133 ms, ventricular tachycardia during stress testing or 24 hours Holter) and for T-wave amplitude variability > 30 μV, even using shrinkage, a statistical procedure that protects against over-fitting due to small sample size., Conclusions: The study showed that an increased dispersion of repolarization times in patients with Chagas disease, as measured by the V-index, is significantly correlated with the risk of death in a univariate survival analysis. The V-index captures prognostic information not immediately available from the analysis of other established risk factors.

Introduction and Objectives: Trypanosoma cruzi infection has been shown to induce humoral autoimmune responses against host antigens tissues. Particularly, antibodies cross-reacting with myocardial antigens may play a role in the development of the severe forms of chronic Chagas disease. The aim of this study was to determine the association between clinical stage of the disease and the presence of autoantibodies in patients with chronic Chagasic disease., Methods: We performed a cross-sectional study in T. cruzi-seropositive patients divided into 3 groups according to the classic classification of chronic Chagas heart of Storino et al. All participants underwent complete clinical examination and their sera were used to measure autoantibody levels., Results: All patients had detectable levels of anti-p2β and anti-B13 autoantibodies but none had anti-Na-K-ATPase antibodies. No association was observed between electrocardiographic conduction disturbances and autoantibody levels. Patients with chronic Chagas disease stage III had the highest levels of anti-B13 antibodies and a high risk of mortality score, showing a clear association between disease stage and this score., Conclusions: Anti-B13 antibodies were significantly higher in chronic Chagas disease stage III patients, suggesting that these antibodies may be involved in disease progression and that they might be a useful marker of poor prognosis in terms of heart compromise. Our results also reveal an important correlation between the level of anti-B13 autoantibodies and symptomatic heart failure and/or dilated cardiomyopathy., (Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

Background: Transforming growth factor-β1 (TGF-β1) may be implicated in the development of Chagas heart disease. However, the clinical value of TGF-β1 measurement is yet to be determined., Methods: We retrospectively analyzed the outcome of 54 Chagas disease patients without heart failure and with left ventricular (LV) ejection fraction >45% whose TGF-β1 serum values were determined between January 1998 and December 1999. Primary end point was all-cause mortality and secondary end point was the combination of all-cause mortality or hospitalization due to worsening heart failure or cardiac arrhythmias., Results: TGF-β1 was independently associated with the occurrence of the primary and secondary end points. The optimal cutoff for TGF-β1 to identify the primary end point was 12.9 ng/ml (area under the curve = 0.82, p = 0.004, sensitivity 100%, and specificity 57%) and to identify the secondary end point was 30.8 ng/ml (area under the curve = 0.72, p = 0.03, sensitivity 60%, and specificity 86%). LV ejection fraction and LV end-diastolic diameter were also independent predictors of the primary and secondary endpoints, respectively., Conclusion: The described association between TGF-β1 and clinical outcome provides evidence towards the clinical value of TGF-β1 in Chagas disease.

Background: Chagas cardiomyopathy and ischemic heart disease (IHD) are frequent causes of chronic systolic heart failure (CHF) in areas where the former is endemic. Nonetheless, a specific comparison of outcome and role of etiology of CHF failure has not been performed in patients with both conditions., Methods: Two-hundred twenty two patients with Chagas cardiomyopathy and 79 with IHD with CHF were included in the study. A Cox proportional hazards model was used to establish independent predictors of mortality for the studied population. Survival analysis was performed with the Kaplan-Meir product limit method., Results: In the multivariable model, Beta-Blocker therapy [(hazard ratio (HR)=0.36; 95% confidence interval (CI) 0.24 to 0.52; p<0.005)], Chagas etiology of CHF (HR=3.6; 95% CI 2.0 to 6.5; p<0.005), serum sodium levels (HR=0.95; 95% CI 0.91 to 0.98; p<0.005), digoxin use (HR=2.1; 95% CI 1.19 to 3.80, p=0.01), and spironolactone use (HR=1.7; 95% CI 1.10 to 2.80; p=0.02) were determined independent predictors of all-cause mortality for this cohort. Probability of survival at 12, 24, 36, 48, and 60 months was 92%, 92%, 88%, 81%, and 78%, respectively, in IHD patients, and 79%, 61%, 49%, 41%, and 35%, respectively, in Chagas cardiomyopathy patients (p<0.005)., Conclusion: Outcome in patients with chronic systolic heart failure secondary to Chagas cardiomyopathy is poorer than that seen in those with IHD., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Aims: Implantable cardioverter-defibrillators (ICDs) are now a first-line option for prevention of sudden death in Chagas disease (ChD). However, efficacy and safety of ICD treatment in ChD remains controversial. The aim of our study was to compare clinical outcome after ICD implantation in ChD and non-ChD patients., Methods and Results: The study population consists of patients who received ICD implantation in a tertiary Reference Center for ChD in Brazil. The primary endpoint of the study was appropriate therapy (appropriate shocks or anti-tachycardia pacing); the secondary endpoint was the event-free survival defined as absence of death or appropriate therapy. One hundred and thirty-five [corrected] patients were followed for the median time of 266 days. Sixty-five patients had ChD. Appropriate ICD therapy occurred in 32 (49.2%) ChD and in 19 (27.1%) non-ChD patients (P=0.005). Ventricular tachycardia occurred in 27 (42%) ChD and in 16 (23%) non-ChD (P = 0.01) patients. There was a statistically significant difference in event-free survival between the group of patients with and without ChD (P=0.004). The median event-free survival was 230 days (95% confidence interval, CI: 113-347) in patients with ChD and 549 days (95% CI: 412-687) in non-ChD patients. Chagas disease double the risk of the patient to have appropriate therapy (hazard ratio, HR = 2.2, 95% CI = 1.2-4.3, P = 0.02) and appropriate therapy or death (HR = 2.2, 95% CI = 1.2-4.2, P = 0.01) in multivariate analysis. There were 16 deaths (11.8%) with 8 deaths in each group and five inappropriate shocks (3.7%) with one in ChD patients (1.6%)., Conclusion: The higher frequency of appropriate ICD therapy and the shorter event-free survival in ChD patients are consistent with the presence of an arrhythmogenic substrate that characterizes this cardiomyopathy.

Background: Sudden death has been considered the main cause of death in patients with Chagas heart disease. Nevertheless, this information comes from a period before the introduction of drugs that changed the natural history of heart failure. We sought to study the mode of death of patients with heart failure caused by Chagas heart disease, comparing with non-Chagas cardiomyopathy., Methods and Results: We examined the REMADHE trial and grouped patients according to etiology (Chagas vs non-Chagas) and mode of death. The primary end-point was all-cause, heart failure and sudden death mortality; 342 patients were analyzed and 185 (54.1%) died. Death occurred in 56.4% Chagas patients and 53.7% non-Chagas patients. The cumulative incidence of all-cause mortality and heart failure mortality was significantly higher in Chagas patients compared to non-Chagas. There was no difference in the cumulative incidence of sudden death mortality between the two groups. In the Cox regression model, Chagas etiology (HR 2.76; CI 1.34-5.69; p = 0.006), LVEDD (left ventricular end diastolic diameter) (HR 1.07; CI 1.04-1.10; p<0.001), creatinine clearance (HR 0.98; CI 0.97-0.99; p = 0.006) and use of amiodarone (HR 3.05; CI 1.47-6.34; p = 0.003) were independently associated with heart failure mortality. LVEDD (HR 1.04; CI 1.01-1.07; p = 0.005) and use of beta-blocker (HR 0.52; CI 0.34-0.94; p = 0.014) were independently associated with sudden death mortality., Conclusions: In severe Chagas heart disease, progressive heart failure is the most important mode of death. These data challenge the current understanding of Chagas heart disease and may have implications in the selection of treatment choices, considering the mode of death., Trial Registration: ClinicalTrials.gov NCT00505050 (REMADHE).

Background: Heart failure (HF) is a condition with poor outcome, especially in advanced cases. Determination of B-type natriuretic peptide (BNP) levels is useful in the diagnosis of cardiac decompensation and has also been proving useful in the prognostic evaluation., Objectives: To verify whether BNP levels are able to identify patients with a poorer outcome and whether it is an independent prognostic factor considering age, gender, cardiac and renal functions, as well as the cause of heart disease., Methods: 189 patients in functional class III/IV advanced HF were studied. All had systolic dysfunction and had their BNP levels determined during hospitalization. Variables related to mortality were studied using univariate and multivariate analyses., Results: BNP levels were higher in patients who died in the first year of follow-up (1,861.9 versus 1,408.1 pg/dL; p = 0.044) and in chagasic patients (1,985 versus 1,452 pg/mL; p = 0.001); the latter had a higher mortality rate in the first year of follow-up (56% versus 35%; p = 0.010). The ROC curve analysis showed that the BNP level of 1,400 pg/mL was the best predictor of events; high levels were associated with lower LVEF (0.23 versus 0.28; p = 0.002) and more severe degree of renal dysfunction (mean urea 92 versus 74.5 mg/dL; p = 0.002)., Conclusion: In advanced HF, high BNP levels identified patients at higher risk of a poorer outcome. Chagasic patients showed higher BNP levels than those with heart diseases of other causes, and have poorer prognosis.

Background: Chagas disease affects mainly poor populations in Latin America. This review assesses the evidence on the independent risk of cardiovascular events associated with positive Chagas serology., Methods: We searched for studies using the following outcomes: death, stroke, new onset heart failure, heart failure hospitalization or evidence of left ventricular dysfunction. Studies comparing patients with positive serology for Chagas with a control group with a follow-up longer than 1 year were selected. The Medline, Lilacs and Embase databases were searched on 21 January 2011 without restrictions., Results: From 5236 potentially relevant studies, 25 fulfilled the inclusion criteria. Fourteen included patients with heart failure, six with severe symptoms and nine with mild symptoms or asymptomatic patients with low ejection fraction. In four studies of patients in functional class III or IV and in three studies of patients with mild symptoms, a higher risk of death was reported among those with positive serology for Chagas. Of the 11 studies of patients without symptoms or low ejection fraction, 3 showed a higher risk of mortality related to Chagas exposure. Two of these were based on the same cohort of people aged >60 years. Overall, 8 out of the 14 heart failure studies and 2 out of the 11 heart damage studies adjusted for confounding factors., Conclusion: Positive serology for Chagas is associated with a higher risk of death for patients with heart failure. However, there is little evidence to link positive serology for Chagas with cardiovascular events in asymptomatic subjects.

Chagas disease continues to be an important cause of cardiac disease in many countries of Latin America. Dilated cardiomyopathy constitutes the more severe manifestation and main cause of death in the disease. Typical clinical presentations include three basic syndromes: heart failure, cardiac arrhythmia and thromboembolism. The identification of markers related to the progression of Chagas heart disease is relevant for appropriate patient management. The most important predictors of death are New York Heart Association functional class, left ventricular systolic dysfunction and nonsustained ventricular tachycardia, which reflect the severity of myocardial damage. Several other potential prognostic factors have recently been reported. Scores for mortality prediction using a combination of prognostic variables have contributed to overall improvement in risk stratification in the setting of Chagas disease.