Chagas Cardiomyopathy: An Update of Current Clinical Knowledge and Management: A Scientific Statement From the American Heart Association

GWAS loci associated with Chagas cardiomyopathy influences DNA methylation levels

A recent genome-wide association study (GWAS) identified a locus in chromosome 11 associated with the chronic cardiac form of Chagas disease. Here we aimed to elucidate the potential functional mechanism underlying this genetic association by analyzing the correlation among single nucleotide polymorphisms (SNPs) and DNA methylation (DNAm) levels as cis methylation quantitative trait loci (cis-mQTL) within this region. A total of 2,611 SNPs were tested against 2,647 DNAm sites, in a subset of 37 chronic Chagas cardiomyopathy patients and 20 asymptomatic individuals from the GWAS. We identified 6,958 significant cis-mQTLs (False Discovery Rate [FDR]<0.05) at 1 Mb each side of the GWAS leading variant, where six of them potentially modulate the expression of the SAC3D1 gene, the reported gene in the previous GWAS. In addition, a total of 268 cis-mQTLs showed differential methylation between chronic Chagas cardiomyopathy patients and asymptomatic individuals. The most significant cis-mQTLs mapped in the gene bodies of POLA2 (FDR = 1.04x10^-11), PLAAT3 (FDR = 7.22x10^-03), and CCDC88B (FDR = 1.89x10^-02) that have been associated with cardiovascular and hematological traits in previous studies. One of the most relevant interactions correlated with hypermethylation of CCDC88B. This gene is involved in the inflammatory response, and its methylation and expression levels have been previously reported in Chagas cardiomyopathy. Our findings support the functional relevance of the previously associated genomic region, highlighting the regulation of novel genes that could play a role in the chronic cardiac form of the disease.

Genome-wide association studies (GWAS) have provided extensive information regarding the genetic component of complex traits, including parasitic diseases such as Chagas disease. However, these associations mapped in regulatory regions of the genome and assigning them a functional consequence have been cumbersome. In this study we aimed to evaluate the functional mechanism underlying the previously reported genomic association with chronic Chagas cardiomyopathy, by assessing the correlation between methylation changes and the underlying genetic variations within the region. These methylation quantitative trait loci (mQTLs) may be involved in gene expression regulation. We identified mQTLs in three genes that have been associated with cardiovascular diseases in previous studies. Interestingly, one of these genes was previously identified as differentially methylated and expressed in heart biopsies of chronic Chagas cardiomyopathy patients. Our results suggest novel genes that could play a role in the chronic Chagas cardiomyopathy, evidencing the functional relevance of the previously associated loci.

Mortality risk in chronic Chagas cardiomyopathy: a systematic review and meta-analysis

Aims

This study aimed to estimate the annual mortality risk and its determinants in chronic Chagas cardiomyopathy.

Methods and results

We conducted a systematic search in MEDLINE, Web of Science Core Collection, Embase, Cochrane Library, and LILACS. Longitudinal studies published between 1 January 1946 and 24 October 2018 were included. A random‐effects meta‐analysis using the death rate over the mean follow‐up period in years was used to obtain pooled estimated annual mortality rates. Main outcomes were defined as all‐cause mortality, including cardiovascular, non‐cardiovascular, heart failure, stroke, and sudden cardiac deaths. A total of 5005 studies were screened for eligibility. A total of 52 longitudinal studies for chronic Chagas cardiomyopathy including 9569 patients and 2250 deaths were selected. The meta‐analysis revealed an annual all‐cause mortality rate of 7.9% [95% confidence interval (CI): 6.3–10.1; I² = 97.74%; T² = 0.70] among patients with chronic Chagas cardiomyopathy. The pooled estimated annual cardiovascular death rate was 6.3% (95% CI: 4.9–8.0; I² = 96.32%; T² = 0.52). The annual mortality rates for heart failure, sudden death, and stroke were 3.5%, 2.6%, and 0.4%, respectively. Meta‐regression showed that low left ventricular ejection fraction (coefficient = −0.04; 95% CI: −0.07, −0.02; P = 0.001) was associated with an increased mortality risk. Subgroup analysis based on American Heart Association (AHA) classification revealed pooled estimate rates of 4.8%, 8.7%, 13.9%, and 22.4% (P < 0.001) for B1/B2, B2/C, C, and C/D stages of cardiomyopathy, respectively.

Conclusions

The annual mortality risk in chronic Chagas cardiomyopathy is substantial and primarily attributable to cardiovascular causes. This risk significantly increases in patients with low left ventricular ejection fraction and those classified as AHA stages C and C/D.

The Association Between Physical Performance and Health-Related Quality of Life Based on the EuroQol 5-Dimensional Questionnaire in Patients With Chagas Disease

OBJECTIVES

Chagas disease (CD) is a chronic disease to millions worldwide, and many patients develop heart disease. In addition, they are part of an aging population. These characteristics can be associated with a reduction in physical performance and health-related quality of life (HRQoL). This study evaluated HRQoL, and the relationship between physical performance and HRQoL in patients with chronic CD.

METHODS

We used the 3-level version of EuroQol 5-dimensional questionnaire (EQ-5D-3L), with the visual analog scale (VAS). Physical performance was measured with 30-s chair-stand test (30sCST) and timed up and go test (TUGT).

RESULTS

Sixty-three patients were evaluated. The majority were women (68.2%) aged 67.7 ± 9.7 years. Overall EQ-5D-3L utility index was 0.65 ± 0.28, and VAS score was 68.4 ± 25.1. Most patients with intermediate and high performance in 30sCST referred no problems in the domains "mobility," "usual activities," and "pain/feeling ill" (P < .001, P = .01, and P = .025, respectively). In a similar way, most patients with intermediate and high performance in TUGT referred no problems in "mobility" (P < .0001) and "usual activities" (P = .001). Higher performance in both tests was associated with higher overall EQ-5D-3L utility and VAS scores. HRQoL measured by EQ-5D-3L was associated with physical status in a cohort of patients with chronic CD. The results underscore the contribution of physical performance, measured by 2 inexpensive and safe physical tests, to HRQoL in these patients.

CONCLUSION

Strategies aiming the improvement of HRQoL in patients with CD may focus on mobility skills and force. Future studies evaluating interventions in physical performance should be a priority in these patients.

Cardiovascular biomarkers as predictors of adverse outcomes in chronic Chagas cardiomyopathy

BACKGROUND

Chronic Chagas Cardiomyopathy (CCM) is a unique form of cardiomyopathy compared to other etiologies of heart failure. In CCM, risk prediction based on biomarkers has not been well-studied. We assessed the prognostic value of a biomarker panel to predict a composite outcome (CO), including the need for heart transplantation, use of left ventricular assist devices, and mortality.

METHODS

Prospective cohort study of 100 adults with different stages of CCM. Serum concentrations of amino-terminal pro-B type natriuretic peptide (NT-proBNP), galectin-3 (Gal-3), neutrophil gelatinase-associated lipocalin (NGAL), high sensitivity troponin T (hs-cTnT), soluble (sST2), and cystatin-C (Cys-c) were measured. Survival analyses were performed using Cox proportional hazard models.

RESULTS

During a median follow-up of 52 months, the mortality rate was 20%, while the CO was observed in 25% of the patients. Four biomarkers (NT-proBNP, hs-cTnT, sST2, and Cys-C) were associated with the CO; concentrations of NT-proBNP and hs-cTnT were associated with the highest AUC (85.1 and 85.8, respectively). Combining these two biomarkers above their selected cut-off values significantly increased risk for the CO (HR 3.18; 95%CI 1.31-7.79). No events were reported in the patients in whom the two biomarkers were under the cut-off values, and when both levels were above cut-off values, the CO was observed in 60.71%.

CONCLUSION

The combination of NT-proBNP and hs-TnT above their selected cut-off values is associated with a 3-fold increase in the risk of the composite outcome among CCM patients. The use of cardiac biomarkers may improve prognostic evaluation of patients with CCM.

Assessing antibody decline after chemotherapy of early chronic Chagas disease patients

BACKGROUND

Chagas disease remains a significant public health problem in Latin America. There are only two chemotherapy drugs, nifurtimox and benznidazole, and both may have severe side effects. After complete chemotherapy of acute cases, seropositive diagnosis may revert to negative. However, there are no definitive parasitological or serological biomarkers of cure.

METHODS

Following a pilot study with seven Bolivian migrants to Spain, we tested 71 serum samples from chronic patients (mean age 12.6 years) inhabiting the Argentine Chaco region. Benznidazole chemotherapy (5-8 mg/kg day, twice daily for 60 days) was administered during 2011-2016. Subsequently, pre-and post-chemotherapy serum samples were analysed in pairs by IgG1 and IgG ELISA using two different antigens and Chagas Sero K-SeT rapid diagnostic tests (RDT). Molecular diagnosis by kDNA-PCR was applied to post-treatment samples.

RESULTS

Pilot data demonstrated IgG1 antibody decline in three of seven patients from Bolivia 1 year post-treatment. All Argentine patients in 2017 (averaging 5 years post-treatment), except one, were positive by conventional serology. All were kDNA-PCR-negative. Most (91.5%) pre-treatment samples were positive by the Chagas Sero K-SeT RDT, confirming the predominance of TcII/V/VI. IgG1 and IgG of Argentine patients showed significant decline in antibody titres post-chemotherapy, with either lysate (IgG, P = 0.0001, IgG1, P = 0.0001) or TcII/V/VI peptide antigen (IgG, P = 0.0001, IgG1, P = 0.0001). IgG1 decline was more discriminative than IgG. Antibody decline after treatment was also detected by the RDT. Incomplete treatment was associated with high IgG1 post-treatment titres against lysate (P = 0.013), as were IgG post-treatment titres to TcII/V/VI peptide (P = 0.0001). High pre-treatment IgG1 with lysate was associated with Qom ethnicity (P = 0.045). No associations were found between gender, age, body mass index and pre- or post-treatment antibody titres.

CONCLUSIONS

We show that following chemotherapy of early chronic Chagas disease, significant decline in IgG1 antibody suggests cure, whereas sustained or increased IgG1 is a potential indicator of treatment failure. Due to restricted sensitivity, IgG1 should not be used as a diagnostic marker but has promise, with further development, as a biomarker of cure. We show that following chemotherapy of early chronic Chagas disease, a significant decline in IgG1 antibody suggests cure, whereas sustained or increased IgG1 is a potential indicator of treatment failure. Due to restricted sensitivity, IgG1 should not be used as a diagnostic marker but has promise, with further development, as a biomarker of cure.

Where was my patient born? The Intersection of tropical medicine and migrant health

PURPOSE OF REVIEW

There is unprecedented movement of people across international borders and parasitic infections, previously restricted to endemic regions, are now encountered in nonendemic areas of the world.

RECENT FINDINGS

Migrants may import parasitic infections acquired in their countries of origin. Increasingly, clinicians in nonendemic regions are faced with patients with neglected diseases such as Chagas disease, malaria and strongyloidiasis. There are gaps in knowledge among physicians in nonendemic regions, which lead to missed opportunities for preventive strategies and early treatment. Both primary care and infectious disease physicians should have a broad knowledge of common parasitic infections to improve health outcomes and decrease healthcare disparities through early identification and treatment of disease encountered in migrants.

SUMMARY

Migrant health is still a young field in medicine; clinicians should be aware of diseases seen in migrants, and access both educational and clinical resources, including experts in tropical medicine, in order to reduce health disparities among migrants. Collaboration between primary care and infectious disease/tropical medicine experts should be strengthened.

Trypanocidal therapy among children infected by Trypanosoma cruzi. Serological and electrocardiographic changes over a mean twenty-five-years follow-up period

This study compared the serological and electrocardiographic evolution among patients with chronic T. cruzi infection treated during childhood or left untreated. A retrospective cohort study was conducted during a mean follow-up period of 25 years in 82 patients: half of them underwent treatment (nifurtimox 8, benznidazole 33) before being 15 years old, whereas the other half remained untreated. During the follow-up, negative seroconversion occurred in 92.7% of the treated children, while all the untreated ones remained positive for conventional serology. At baseline, 2 patients from each group had electrocardiographic abnormalities. During the study period, 4/41 (9.75%) and 9/41 (21.95%) of treated and untreated patients displayed an altered electrocardiogram, respectively. In multivariate analyses, the probability of developing electrocardiographic abnormalities was significantly reduced among treated patients (OR = 0.18, 95% CI = 0.04-0.79; p = 0.023). Electrocardiographic abnormalities attributable to Chagas cardiomyopathy were seen in 3 patients from the untreated group (complete right bundle branch block + left anterior fascicular block, frequent ventricular extrasystole, and left anterior fascicular block). The remarkable seronegativization seen in Benznidazole and Nifurtimox recipients underlines the parasiticidal effect of both compounds. Such demonstration along with the fact that CCC-related alterations were only present in the untreated group, reinforces the view of trypanocidal treatment in chronically T. cruzi-infected children as decreasing the risk for cardiomyopathy development.

Central role of metabolism in Trypanosoma cruzi tropism and Chagas disease pathogenesis

Chagas disease is a neglected tropical disease caused by Trypanosoma cruzi parasites. During mammalian infection, T. cruzi alternates between an intracellular stage and extracellular stage. T. cruzi adapts its metabolism to this lifestyle, while also reshaping host metabolic pathways. Such host metabolic adaptations compensate for parasite-induced stress, but may promote parasite survival and proliferation. Recent work has demonstrated that metabolism controls parasite tropism and location of Chagas disease symptoms, and regulates whether infection is mild or severe. Such findings have important translational applications with regards to treatment and diagnostic test development, though further research is needed with regards to in vivo parasite metabolic gene expression, relationship between magnitude of local metabolic perturbation, parasite strain and disease location, and host-parasite-microbiota co-metabolism.

Systemic cytokines, chemokines and growth factors reveal specific and shared immunological characteristics in infectious cardiomyopathies

Heart disease is a major cause of death worldwide. Chronic Chagas cardiomyopathy (CCC) caused by infection with Trypanosoma cruzi leading to high mortality in adults, and rheumatic heart disease (RHD), resulting from infection by Streptococcus pyogenes affecting mainly children and young adults, are amongst the deadliest heart diseases in low-middle income countries. Despite distinct etiology, the pathology associated with both diseases is a consequence of inflammation. Here we compare systemic immune profile in patients with these cardiopathies, to identify particular and common characteristics in these infectious heart diseases. We evaluated the expression of 27 soluble factors, employing single and multivariate analysis combined with machine-learning approaches. We observed that, while RHD and CCC display higher levels of circulating mediators than healthy individuals, CCC is associated with stronger immune activation as compared to RHD. Despite distinct etiologies, univariate analysis showed that expression of TNF, IL-17, IFN-gamma, IL-4, CCL4, CCL3, CXCL8, CCL11, CCL2, PDGF-BB were similar between CCC and RHD, consistent with their inflammatory nature. Network analysis revealed common inflammatory pathways between CCC and RHD, while highlighting the broader reach of the inflammatory response in CCC. The final multivariate model showed a 100% discrimination power for the combination of the cytokines IL-12p70, IL-1Ra, IL-4, and IL-7 between CCC and RHD groups. Thus, while clear immunological distinctions were identified between CCC and RHD, similarities indicate shared inflammatory pathways in these infectious heart diseases. These results contribute to understanding the pathogenesis of CCC and RHD and may impact the design of immune-based therapies for these and other inflammatory cardiopathies that may also share immunological characteristics.

Cohort profile update: the main and new findings from the SaMi-Trop Chagas cohort

The SaMi-Trop project is a cohort study conducted in 21 municipalities of endemic areas of Chagas disease, including 1,959 patients with chronic Chagas cardiomyopathy. In this article we updated the results of the project, adding information from the second cohort visit. Trypanosoma cruzi-seropositive patients were enrolled from the primary care Telehealth service in Minas Gerais State, Brazil. The eligibility criterium for the second visit was the participation in the baseline evaluation. Of 1,959 participants at the baseline assessment, 1,585 (79.9%) returned after two years for the second evaluation. The mortality rate was 6.7%, but varied from 0.9% to 18.2% when it was stratified by certain clinical characteristics. A lower age-adjusted NT-Pro-BNP level (less than 300) and a prior benznidazole treatment were associated with lower mortality. There was an improvement in most quality of life domain scores. Participants have also reported fewer signs and symptoms and greater use of medication. The second follow-up visit will be complete in Oct 2021.

Inhibition of calcium/calmodulin (Ca2+ /CaM)-Calcium/calmodulin-dependent protein kinase II (CaMKII) axis reduces in vitro and ex vivo arrhythmias in experimental Chagas disease

Chagasic cardiomyopathy (CCC) is one of the main causes of heart failure and sudden death in Latin America. To date, there is no available medication to prevent or reverse the onset of cardiac symptoms. CCC occurs in a scenario of disrupted calcium dynamics and enhanced oxidative stress, which combined, may favor the hyper activation of calcium/calmodulin (Ca²⁺ /CaM)-calcium/calmodulin-dependent protein kinase II (CaMKII) (Ca²⁺ /CaM-CaMKII) pathway, which is fundamental for heart physiology and it is implicated in other cardiac diseases. Here, we evaluated the association between Ca²⁺ /CaM-CaMKII in the electro-mechanical (dys)function of the heart in the early stage of chronic experimental Trypanosoma cruzi infection. We observed that in vitro and ex vivo inhibition of Ca²⁺ /CaM-CaMKII reversed the arrhythmic profile of isolated hearts and isolated left-ventricles cardiomyocytes. The benefits of the limited Ca²⁺ /CaM-CaMKII activation to cardiomyocytes' electrical properties are partially related to the restoration of Ca²⁺ dynamics in a damaged cellular environment created after T. cruzi infection. Moreover, Ca²⁺ /CaM-CaMKII inhibition prevented the onset of arrhythmic contractions on isolated heart preparations of chagasic mice and restored the responsiveness to the increase in the left-ventricle pre-load. Taken together, our data provide the first experimental evidence for the potential of targeting Ca²⁺ /CaM-CaMKII pathway as a novel therapeutic target to treat CCC.

Signal Transducer and Activator of Transcription-3 Modulation of Cardiac Pathology in Chronic Chagasic Cardiomyopathy

Chronic Chagasic cardiomyopathy (CCC) is a severe clinical manifestation that develops in 30%–40% of individuals chronically infected with the protozoal parasite Trypanosoma cruzi and is thus an important public health problem. Parasite persistence during chronic infection drives pathologic changes in the heart, including myocardial inflammation and progressive fibrosis, that contribute to clinical disease. Clinical manifestations of CCC span a range of symptoms, including cardiac arrhythmias, thromboembolic disease, dilated cardiomyopathy, and heart failure. This study aimed to investigate the role of signal transducer and activator of transcription-3 (STAT3) in cardiac pathology in a mouse model of CCC. STAT3 is a known cellular mediator of collagen deposition and fibrosis. Mice were infected with T. cruzi and then treated daily from 70 to 91 days post infection (DPI) with TTI-101, a small molecule inhibitor of STAT3; benznidazole; a combination of benznidazole and TTI-101; or vehicle alone. Cardiac function was evaluated at the beginning and end of treatment by echocardiography. By the end of treatment, STAT3 inhibition with TTI-101 eliminated cardiac fibrosis and fibrosis biomarkers but increased cardiac inflammation; serum levels of interleukin-6 (IL-6), and IFN−γ; cardiac gene expression of STAT1 and nuclear factor-κB (NF-κB); and upregulation of IL-6 and Type I and Type II IFN responses. Concurrently, decreased heart function was measured by echocardiography and myocardial strain. These results indicate that STAT3 plays a critical role in the cardiac inflammatory–fibrotic axis during CCC.

A Southwestern United States Pilot Investigation of Triatomine-Mite Prevalence

Simple Summary

An estimated 70 million persons in the Western Hemisphere are living at risk for Chagas disease, a parasitic infection transmitted to humans by over 156 different competent triatomine insect vector species. Prior Pan American Health Organization insecticide campaigns throughout Latin America in the 1990s and 2000s demonstrated that domestic insecticide spraying had temporary effects, which resulted in the re-establishment of triatomine species within a few years. Serendipitously, our team found ectoparasitic mites parasitizing triatomines collected from the field in multiple locations in the southwestern United States, where human–triatomine interaction was high but human parasite infection remains low. Upon further investigation of 408 triatomines collected across multiple field sampling sites in Arizona and New Mexico, 13% were found to be parasitized by mites. Mites were found on both Triatoma rubida and Triatoma protracta species and corporally dispersed on the head, thorax, abdomen and legs of these species. Interestingly, there was no statistical difference in Trypanosoma cruzi infection status between parasitized and unparasitized triatomines. Upon further review of the scientific literature, two Latin American-based studies suggest that the presence of mites on triatomines might reduce vector competency via decreased fitness and fecundity. This study provides the first contemporary report of triatomine ectoparasitism, which warrants further investigation as the biologic role of this host-attached mites on Trypanosoma cruzi transmission efficacy.

Abstract

Background: Chagas disease is a leading cause of cardiac failure in Latin America. Due to poor safety profiles and efficacy of currently available therapeutics, prevention is a priority for the millions living at risk for acquiring this clinically important vector-borne disease. Triatomine vectors of the Chagas disease parasite, Trypanosoma cruzi, are found in the southwestern United States, but risk for autochthonous transmission is thought to be low. The role of ectoparasitic mites is under-explored regarding the ecology of triatomines and Chagas disease transmission. Methods: Triatomine collections were performed using three common entomologic techniques in 2020–2021 from four different locations in southern Arizona and New Mexico. Triatomines were analyzed visually under a 112.5× microscope for the presence of externally attached mites. Following mite removal, triatomines were tested for T. cruzi infection by PCR. Results: Approximately 13% of the collected triatomines had mites securely attached to their head, thorax, abdomen, and legs. More than one mite attached was a common finding among ectoparasitized triatomines. Mite presence, however, did not statistically influence triatomine T. cruzi status. Conclusions: Our findings add to a growing body of literature demonstrating the sustainability of mite-infested triatomine populations throughout the Western Hemisphere. Future investigations are warranted to better understand the biologic impact of triatomine mites and their potential to serve as a potential biological control tool.

Inflammatory Cardiomyopathy: Case-based Review on Clinical Presentation, Diagnosis, and Management

Inflammatory cardiomyopathy is a broad term encompassing any disease leading to myocardial inflammation with associated cardiac dysfunction. While endomyocardial biopsy remains the gold standard for diagnosis, noninvasive imaging techniques, such as cardiac magnetic resonance imaging and positron emission tomography, have become powerful tools to facilitate the identification of underlying myocardial inflammation. This review presents a series of clinical cases with some common etiologies of inflammatory cardiomyopathy, including diagnosis and management.

A systematic review of historical and current trends in Chagas disease

Introduction

Chagas disease (CD) is caused by Trypanosoma cruzi. When acquired, the disease develops in stages. For diagnosis, laboratory confirmation is required, and an extensive assessment of the patient's health should be performed. Treatment consists of the administration of trypanocidal drugs, which may cause severe adverse effects. The objective of our systematic review was to analyze data contained in the CD published case reports to understand the challenges that patients and clinicians face worldwide.

Materials and methods

We performed a systematic review following the PRISMA guidance. PubMed database was explored using the terms 'American trypanosomiasis' or 'Chagas disease'. Results were limited to human case reports written in English or Spanish. A total of 258 reports (322 patients) were included in the analysis. Metadata was obtained from each article. Following this, it was analyzed to obtain descriptive measures.

Results

From the sample, 56.2% were males and 43.8% were females. Most cases were from endemic countries (85.4%). The most common clinical manifestations were fever during the acute stage (70.0%), dyspnea during the chronic stage in its cardiac form (53.7%), and constipation during the chronic stage in its digestive form (73.7%). Most patients were diagnosed in the chronic stage (72.0%). Treatment was administered in 56.2% of cases. The mortality rate for the acute stage cases was 24.4%, while for the chronic stage this was 28.4%.

Discussion

CD is a parasitic disease endemic to Latin America, with increasing importance due to human and vector migration. In this review, we report reasons for delays in diagnosis and treatment, and trends in medical practices. Community awareness must be increased to improve CD's diagnoses; health professionals should be appropriately trained to detect and treat infected individuals. Furthermore, public health policies are needed to increase the availability of screening and diagnostic tools, trypanocidal drugs, and, eventually, vaccines.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consenus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology, (ACC) and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate follow-up in pediatric patients.

α-Gal immunization positively impacts Trypanosoma cruzi colonization of heart tissue in a mouse model

Chagas disease, caused by the parasite Trypanosoma cruzi, is considered endemic in more than 20 countries but lacks both an approved vaccine and limited treatment for its chronic stage. Chronic infection is most harmful to human health because of long-term parasitic infection of the heart. Here we show that immunization with a virus-like particle vaccine displaying a high density of the immunogenic α-Gal trisaccharide (Qβ-αGal) induced several beneficial effects concerning acute and chronic T. cruzi infection in α1,3-galactosyltransferase knockout mice. Approximately 60% of these animals were protected from initial infection with high parasite loads. Vaccinated animals also produced high anti-αGal IgG antibody titers, improved IFN-γ and IL-12 cytokine production, and controlled parasitemia in the acute phase at 8 days post-infection (dpi) for the Y strain and 22 dpi for the Colombian strain. In the chronic stage of infection (36 and 190 dpi, respectively), all of the vaccinated group survived, showing significantly decreased heart inflammation and clearance of amastigote nests from the heart tissue.

Treatment With Suboptimal Dose of Benznidazole Mitigates Immune Response Molecular Pathways in Mice With Chronic Chagas Cardiomyopathy

Chronic Chagas cardiomyopathy (CCC) is the most frequent and severe form of Chagas disease, a neglected tropical illness caused by the protozoan Trypanosoma cruzi, and the main cause of morbimortality from cardiovascular problems in endemic areas. Although efforts have been made to understand the signaling pathways and molecular mechanisms underlying CCC, the immunological signaling pathways regulated by the etiological treatment with benznidazole (Bz) has not been reported. In experimental CCC, Bz combined with the hemorheological and immunoregulatory agent pentoxifylline (PTX) has beneficial effects on CCC. To explore the molecular mechanisms of Bz or Bz+PTX therapeutic strategies, C57BL/6 mice chronically infected with the T. cruzi Colombian strain (discrete typing unit TcI) and showing electrocardiographic abnormalities were submitted to suboptimal dose of Bz or Bz+PTX from 120 to 150 days postinfection. Electrocardiographic alterations, such as prolonged corrected QT interval and heart parasite load, were beneficially impacted by Bz and Bz+PTX. RT-qPCR TaqMan array was used to evaluate the expression of 92 genes related to the immune response in RNA extracted from heart tissues. In comparison with non-infected mice, 30 genes were upregulated, and 31 were downregulated in infected mice. Particularly, infection upregulated the cytokines IFN-γ, IL-12b, and IL-2 (126-, 44-, and 18-fold change, respectively) and the T-cell chemoattractants CCL3 and CCL5 (23- and 16-fold change, respectively). Bz therapy restored the expression of genes related to inflammatory response, cellular development, growth, and proliferation, and tissue development pathways, most probably linked to the cardiac remodeling processes inherent to CCC, thus mitigating the Th1-driven response found in vehicle-treated infected mice. The combined Bz+PTX therapy revealed pathways related to the modulation of cell death and survival, and organismal survival, supporting that this strategy may mitigate the progression of CCC. Altogether, our results contribute to the better understanding of the molecular mechanisms of the immune response in the heart tissue in chronic Chagas disease and reinforce that parasite persistence and dysregulated immune response underpin CCC severity. Therefore, Bz and Bz+PTX chemotherapies emerge as tools to interfere in these pathways aiming to improve CCC prognosis.

A Rapid Review on the Efficacy and Safety of Pharmacological Treatments for Chagas Disease

Chagas disease remains a neglected tropical disease, causing significant burden in the Americas and countries that receive immigrants from endemic nations. Current pharmaceutical treatments are suboptimal, not only varying drastically in efficacy, depending on the stage of disease, but also presenting significant risk of adverse events. The objective of this review is to provide a timely update on the efficacy and safety of current trypanocidals. Eligible studies published from January 2015 to December 2020 were retrieved by one reviewer from six electronic databases. Ana-lysis was done with review management software and risk of bias was assessed using tools appropriate for the type of study (i.e., experimental or observational). Thirteen studies (10 observational and three RCTs) were included in the analysis. All 13 studies tested Benznidazole (BNZ) or Nifurtimox (NFX), and two studies also tested Posaconazole (POS) or E1224 (Ravucanazole). BNZ was found to be the most efficacious trypanocidal drug compared to Nifurtimox, POS, and E1224; it also resulted in the highest percentage of adverse effects (AEs) and treatment discontinuation due to its toxicity. Adults experienced higher frequency of neurological AEs while taking BNZ or NFX compared to children. Children had a higher frequency of general AEs compared to adults while taking BNZ. Overall, BNZ is still the most efficacious, but development of new, less toxic drugs is paramount for the quality of life of patients. Studies testing combination therapies and shorter regimens are needed, as is the devising of better clinical parameters and laboratory biomarkers to evaluate treatment efficacy. Considering the variability in methodology and reporting of the studies included in the present analysis, we offer some recommendations for the improvement and replicability of clinical studies investigating pharmacological treatment of Chagas disease. These include full disclosure of methodology, standardization of outcome measures, and always collecting and reporting data on both the efficacy of trypanocidals and on safety outcomes.

Clinical and echocardiographic characteristics after six months of sacubitril/valsartan in Chagas heart disease - A case series

Chagas cardiomyopathy is the most prevalent non-ischaemic cardiomyopathy in Latin America, with high morbidity and mortality even today. Treatment of these patients is based on the use of medications for heart failure. This study evaluated a case series of patients with Chagas heart disease who used sacubitril/valsartan at a referral hospital for this disease in Brazil. After 6 months, there was a symptomatic improvement in these individuals assessed by the New York Heart Association (NYHA) functional class, with a 44.3% reduction in the absolute number of patients classified as III-IV in the period (P = 0.035), but without changes in the parameters on the echocardiogram for reverse ventricular remodelling. There was a high mortality rate and number of hospitalizations. These results emphasize the importance of studying the use of sacubitril/valsartan in Chagas heart disease to better describe its effectiveness considering the particularities of these individuals.

Imidazoles and Oxazoles from Lapachones and Phenanthrene-9,10-dione: A Journey through their Synthesis, Biological Studies, and Optical Applications

Diverse structural frameworks are found in natural compounds and are well known for their chemical and biological properties; such compounds include the imidazoles and oxazoles. Researchers worldwide are continually working on the development of methods for synthesizing new molecules bearing these basic moiety and evaluating their properties and applications. To expand the knowledge related to azoles, this review summarizes important examples of imidazole and oxazole derivatives from 1,2-dicarbonyl compounds, such as lapachones and phenanthrene-9,10-diones, not only regarding their synthesis and biological applications but also their photophysical properties and uses. The data concerning the latter are particularly scarce in the literature, which leads to underestimation of the potential applications that can be envisaged for these compounds.

Quality of life in patients with Chagas disease and the instrument used: an integrative review

Chagas disease (CD) is a neglected tropical highly morbid disease that can have a negative impact on the quality of life (QoL). The purpose of this study was to conduct an integrative review to analyze the QoL of patients with CD in the chronic phase of the disease, as well as the instruments used and the effect of different interventions. The review was carried out based on the criteria and recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guideline (PRISMA) using the PubMed, Scopus, Web of Science and Science Direct databases. An analysis of the reference list of the included articles was also carried out. Publications in all languages have been included. Two independent reviewers selected the eligible articles and extracted the data. A total of 1,479 articles were identified, and after applying the inclusion criteria 18 articles were included. Four different instruments were used to assess QoL and the most used was the Minnesota Living with Heart Failure Questionnaire (MLWHFQ) [33.3% (n = 6)]. Investigations involving intervention showed a positive impact on the patients' QoL, and the Environment domain had the lowest score. Heterogeneity of instruments and lack of methodology standardization for assessing QoL was observed. QoL proved to be an important indicator for the planning and monitoring of patients with CD, however it is suggested that the instruments for its assessment should be the ones recommended by the validation studies. This process will allow the comparison of data between investigations.

Comparative Performance of Latest-Generation and FDA-Cleared Serology Tests for the Diagnosis of Chagas Disease

Confirmed diagnosis of chronic Chagas disease (CD) requires positive results by two different IgG serology tests. Variable sensitivity has been reported among tests and in different geographic regions. Inadequate specificity presents a particular challenge in low-prevalence settings such as the United States. This study provides a direct comparison of the latest-generation IgG serology assays with four previously assessed FDA-cleared tests. Seven hundred ten blood donor plasma specimens were evaluated by Wiener Lisado and Wiener v.4.0 enzyme-linked immunosorbent assays (ELISAs) and Abbott PRISM Chagas chemiluminescent assay (ChLIA). Sensitivity and specificity were assessed relative to infection status as determined by the original blood donation testing algorithm. All three latest-generation assays demonstrated 100% specificity (95% confidence interval [CI], 98.6 to 100.0). Wiener Lisado, Wiener v.4.0, and Abbott PRISM had sensitivities of 97.1% (95% CI, 95.1 to 98.4), 98.9% (95% CI, 97.4 to 99.6), and 95.5% (95% CI, 93.2 to 97.3), respectively. As with previously evaluated FDA-cleared tests, all three assays had the highest reactivity and sensitivity in samples from donors born in South America and lowest reactivity and sensitivity in specimens from those born in Mexico, with intermediate results in specimens from Central American donors. Wiener v.4.0 had the highest diagnostic sensitivity in all comparisons. Our findings suggest that the latest-generation CD serology tests could improve diagnostic sensitivity without affecting specificity.

Cardiac diagnostic test results and outcomes in 44 dogs naturally infected with Trypanosoma cruzi

Background

The protozoal parasite Trypanosoma cruzi causes myocarditis in dogs.

Objectives

To describe the cardiac diagnostic test results and outcomes of dogs naturally infected with T. cruzi.

Animals

Forty‐four client‐owned dogs.

Methods

Medical records were retrospectively reviewed to identify dogs with an indirect fluorescent antibody test result for T. cruzi ≥1 : 80. Data collected included signalment, cardiac diagnostic test results (ECG, echocardiography, cardiac troponin I) and outcome. Outcomes were categorized as alive, dead (cardiac or noncardiac) or lost to follow up.

Results

ECG abnormalities were present in 41 dogs with ventricular arrhythmias (n = 28) and atrioventricular block (AVB) (n = 15) most commonly identified. Echocardiographic chamber enlargement was present in 28 dogs and most often included the right ventricle (RV) (n = 15) and left atrium (n = 12). Troponin was ≥2 times the reference range in 20/36 (56%) dogs. In univariate analysis using nonparametric Kaplan‐Meier, ventricular arrhythmias with a modified Lown score ≥2 (P = .02), presence of AVB (P = .04), and RV enlargement (P = .006) were associated with decreased survival times. Right ventricular enlargement (HR 3.6; 95% confidence interval [CI] 1.4‐9.3; P = .007) and higher body weight at presentation (HR 1.0; 95% CI 1.0‐1.1; P = .04) were associated with decreased time to death in the final explanatory multivariable model.

Conclusions and Clinical Importance

Cardiac abnormalities were common and variable, and RV enlargement was associated with shorter survival time. A diagnostic evaluation that includes screening for arrhythmias, echocardiography, and cTnI can provide useful information related to the characterization of heart disease in dogs seropositive for T. cruzi.

Nanocarrier-enhanced intracellular delivery of benznidazole for treatment of Trypanosoma cruzi infection

Chagas disease is caused by infection with the protozoan parasite Trypanosoma cruzi (T. cruzi), an intracellular pathogen that causes significant morbidity and death among millions in the Americas from Canada to Argentina. Current therapy involves oral administration of the nitroimidazole benznidazole (BNZ), which has serious side effects that often necessitate cessation of treatment. To both avoid off-target side effects and reduce the necessary dosage of BNZ, we packaged the drug within poly(ethylene glycol)-block-poly(propylene sulfide) polymersomes (BNZ-PSs). We show that these vesicular nanocarriers enhanced intracellular delivery to phagocytic cells and tested this formulation in a mouse model of T. cruzi infection. BNZ-PS is not only nontoxic but also significantly more potent than free BNZ, effectively reducing parasitemia, intracellular infection, and tissue parasitosis at a 466-fold lower dose of BNZ. We conclude that BNZ-PS was superior to BNZ for treatment of T. cruzi infection in mice and that further modifications of this nanocarrier formulation could lead to a wide range of custom controlled delivery applications for improved treatment of Chagas disease in humans.

Risk of COVID-19 in Chagas Disease Patients: What Happen with Cardiac Affectations?

BACKGROUND

Chagas disease is considered a neglected tropical disease. The acute phase of Chagas disease is characterized by several symptoms: fever, fatigue, body aches, headache and cardiopathy's. Chronic phase could be asymptomatic or symptomatic with cardiac compromise. Since the emergence of the pandemic caused by the SARS-CoV-2 virus, the cardiovascular involvement has been identified as a complication commonly reported in coronavirus disease 2019 (COVID-19). Due to the lack of knowledge of the cardiac affectations that this virus could cause in patients with Chagas disease, the aim of this review is to describe the possible cardiac affectations, as well as the treatment and recommendations that patients with both infections should carry out.

METHODS

The authors revised the recent and relevant literature concerning the topic and discussed advances and limitations of studies on COVID-19 and their impact in Chagas disease patients, principally with cardiac affectations.

RESULTS

There currently exists little information about the consequences that Chagas disease patients can suffer when they are infected with COVID-19.

CONCLUSIONS

This review highlights the emerging challenges of access to medical care and future research needs in order to understand the implications that co-infections (SARS-CoV-2 or other viruses) can generate in Chagas disease-infected people.

Accuracy of health-related quality of life in identifying systolic dysfunction in patients with Chagas cardiomyopathy

OBJECTIVE

Systolic dysfunction is a well-established marker of mortality in patients with Chagas cardiomyopathy (CC). However, its diagnosis is expensive and useful tools for screening these patients are required. The evaluation of the health-related quality of life (HRQoL) detects the patient's perception of the disease's impact. However, its accuracy in identifying patients with CC and systolic dysfunction is unknown. The study aimed to verify the sensitivity, specificity and predictive values of the physical and mental components related to HRQoL in identifying patients with CC and systolic dysfunction.

METHODS

75 patients with CC, aged 49 (95% confidence interval: 47-51) years, were evaluated by echocardiography and Short-Form of Health Survey (SF-36) questionnaire. Systolic dysfunction was defined by left ventricular ejection fraction <52% for men and <54% for women and left ventricular diastolic diameter >55 mm.

RESULTS

Most patients (73%) had systolic dysfunction, with lower HRQoL values in the physical functioning, physical role functioning and general health perceptions domains and in the physical component summary. The accuracy of identifying patients with systolic dysfunction by the scores of physical components was 73% and 62% of mental components. The optimal cut-off point was 46 for physical and 54 for mental components, with respective positive predictive values of 91% and 80%.

CONCLUSION

The evaluation of the HRQoL by the SF-36, a low-cost instrument, can be useful in identifying patients with systolic dysfunction, assisting in the screening and risk stratification of patients.

Deriving a parsimonious cardiac endpoint for use in epidemiological studies of Chagas disease: results from the Retrovirus Epidemiology Donor Study-II (REDS-II) cohort

Chagas cardiomyopathy (ChCM) is a severe consequence of Trypanosoma cruzi infection and has a range of electrocardiographic (ECG) and echocardiographic (ECHO) manifestations. There is a need for a standard and parsimonious research cardiac end point that does not rely on expert panel adjudication, and it is not intended to change the ChCM definition. We use data from the REDS-II cohort to propose a simplified cardiac endpoint. A total of 499 T. cruzi-seropositive blood donors were included. All participants underwent a 12-lead ECG, echocardiogram and clinical examination, and those with abnormal findings were reviewed by a panel of cardiologists who classified cases as having Chagas cardiomyopathy or not. We created an exhaustive set of ECG and ECHO finding combinations and compared these with the panel's classification. We selected the simplest combination that most accurately reproduced the panel's results. Individual ECG and ECHO variables had low sensitivity for panel-defined cardiomyopathy. The best performing combination was right bundle branch block and/or ECHO evidence of left ventricular hypocontractility. This combination had 98% specificity and 85% sensitivity for panel-defined ChCM. It was not possible to improve the overall accuracy by addition of any other ECG or ECHO variable. Substituting right bundle branch block for the more inclusive finding of QRS interval > 120 ms produced similar results. The combination of prolonged QRS interval and/or left ventricular hypocontractility closely reproduced the REDS-II expert panel classification of Chagas ChCM. In conclusion, the simple and reproducible research endpoint proposed here captures most of the spectrum of cardiac abnormalities in Chagas disease.

Chagas Cardiomyopathy: From Romaña Sign to Heart Failure and Sudden Cardiac Death

Despite nearly a century of research and accounting for the highest disease burden of any parasitic disease in the Western Hemisphere, Chagas disease (CD) is still a challenging diagnosis, primarily due to its poor recognition outside of Latin America. Although initially considered endemic to Central and South America, globalization, urbanization, and increased migration have spread the disease worldwide in the last few years, making it a significant public health threat. The international medical community's apparent lack of interest in this disease that was previously thought to be geographically restricted has delayed research on the complex host-parasite relationship that determines myocardial involvement and its differential behavior from other forms of cardiomyopathy, particularly regarding treatment strategies. Multiple cellular and molecular mechanisms that contribute to degenerative, inflammatory, and fibrotic myocardial responses have been identified and warrant further research to expand the therapeutic arsenal and impact the high burden attributed to CD. Altogether, cardiac dysautonomia, microvascular disturbances, parasite-mediated myocardial damage, and chronic immune-mediated injury are responsible for the disease's clinical manifestations, ranging from asymptomatic disease to severe cardiac and gastrointestinal involvement. It is crucial for healthcare workers to better understand CD transmission and disease dynamics, including its behavior on both its acute and chronic phases, to make adequate and evidence-based decisions regarding the disease. This review aims to summarize the most recent information on the epidemiology, pathogenesis, clinical presentation, diagnosis, screening, and treatment of CD, emphasizing on Chagasic cardiomyopathy's (Ch-CMP) clinical presentation and pathobiological mechanisms leading to sudden cardiac death.

The Association Between Physical Performance and Health-Related Quality of Life Based on the EuroQol 5-Dimensional Questionnaire in Patients With Chagas Disease

OBJECTIVES

Chagas disease (CD) is a chronic disease to millions worldwide, and many patients develop heart disease. In addition, they are part of an aging population. These characteristics can be associated with a reduction in physical performance and health-related quality of life (HRQoL). This study evaluated HRQoL, and the relationship between physical performance and HRQoL in patients with chronic CD.

METHODS

We used the 3-level version of EuroQol 5-dimensional questionnaire (EQ-5D-3L), with the visual analog scale (VAS). Physical performance was measured with 30-s chair-stand test (30sCST) and timed up and go test (TUGT).

RESULTS

Sixty-three patients were evaluated. The majority were women (68.2%) aged 67.7 ± 9.7 years. Overall EQ-5D-3L utility index was 0.65 ± 0.28, and VAS score was 68.4 ± 25.1. Most patients with intermediate and high performance in 30sCST referred no problems in the domains "mobility," "usual activities," and "pain/feeling ill" (P < .001, P = .01, and P = .025, respectively). In a similar way, most patients with intermediate and high performance in TUGT referred no problems in "mobility" (P < .0001) and "usual activities" (P = .001). Higher performance in both tests was associated with higher overall EQ-5D-3L utility and VAS scores. HRQoL measured by EQ-5D-3L was associated with physical status in a cohort of patients with chronic CD. The results underscore the contribution of physical performance, measured by 2 inexpensive and safe physical tests, to HRQoL in these patients.

CONCLUSION

Strategies aiming the improvement of HRQoL in patients with CD may focus on mobility skills and force. Future studies evaluating interventions in physical performance should be a priority in these patients.

Biomarkers and Their Possible Functions in the Intestinal Microenvironment of Chagasic Megacolon: An Overview of the (Neuro)inflammatory Process

The association between inflammatory processes and intestinal neuronal destruction during the progression of Chagasic megacolon is well established. However, many other components play essential roles, both in the long-term progression and control of the clinical status of patients infected with Trypanosoma cruzi. Components such as neuronal subpopulations, enteric glial cells, mast cells and their proteases, and homeostasis-related proteins from several organic systems (serotonin and galectins) are differentially involved in the progression of Chagasic megacolon. This review is aimed at revealing the characteristics of the intestinal microenvironment found in Chagasic megacolon by using different types of already used biomarkers. Information regarding these components may provide new therapeutic alternatives and improve the understanding of the association between T. cruzi infection and immune, endocrine, and neurological system changes.

Chagas disease is an independent predictor of stroke and death in a cohort of heart failure patients

BACKGROUND AND AIMS

Chagas disease is a common cause of heart failure (HF) and death in developing countries. Although stroke is known to occur in these patients, an accurate estimate of stroke incidence is lacking. We aimed to determine the incidence of stroke and death in patients with HF, comparing Chagas and non-Chagas etiologies.

METHODS

Cohort of stroke-free patients with HF (Framingham criteria) followed in a university-based outpatient clinic in Brazil. Baseline characteristics included sociodemographic, risk factor assessment, echocardiographic and electrocardiographic findings. Chagas disease was defined by appropriate serologic tests. Cause-specific Cox regression was used to search for predictors of stroke or death as separate outcomes.

RESULTS

We studied 565 patients with HF between January 2003 and December 2018, mean age 54.3 ± 12.9 years, 305 (54.0%) females, 271/535 (50.7%) with Chagas disease. Chagas patients were older (55.5 vs. 53.1 years), more frequently women (60.5% vs. 47.3%), less frequently harbored coronary artery disease (14.5% vs. 34.1%) when compared to non-Chagas patients. Echocardiography showed more severe disease among non-Chagas patients [median left ventricle ejection fraction (LVEF) 37.3% vs. 47.0%]. Over a mean 42.9 (±34.4) months, we followed 404 (71.5%) patients, completing 1442 patient-years of follow-up. Stroke incidence was higher in Chagas when compared to non-Chagas patients (20.2 vs. 13.9 events per 1000 patient-years), while death rate was similar (41.6 vs. 43.1 deaths per 1000 patient-years). In the multivariable analysis for stroke outcome adjusted for LVEF and arrhythmias, cause-specific hazard ratio (CSHR) for Chagas was 2.54 (95% confidence interval 1.01-6.42, p = 0.048). Chagas disease was also associated with increased risk of death (CSHR 1.83; 95% confidence interval 1.04-3.24, p = 0.037).

CONCLUSION

Chagas disease is associated with increased risk of stroke and death when compared to other etiologies of HF, independently of HF severity or cardiac arrhythmias, suggesting other factors contribute to increased stroke risk and mortality in Chagas disease. Early prevention and treatment of Chagas disease is imperative to reduce a later risk of stroke in endemic areas.

Wnt Signaling Plays a Key Role in the Regulation of the Immune Response and Cardiac Damage during Trypanosoma cruzi Infection

Chagas cardiomyopathy is the consequence of a compromised electrical and mechanical cardiac function, with parasite persistence, unbalanced inflammation, and pathological tissue remodelling, being intricately related to myocardial aggression and impaired function. Recent studies have shown that Wnt signaling pathways play a critical role in the pathogenesis of cardiac and vascular diseases. In addition, we have reported that Trypanosoma cruzi infection activates Wnt signaling to promote intracellular replication of the parasites in macrophages, with the treatment of mice with IWP-L6 (an inhibitor of the O-acyl-transferase, PORCN, responsible for the post-translational modifications necessary for Wnt protein secretion) being able to diminish parasitemia and tissue parasitism. Here, we show that inhibition of Wnt signaling during the acute phase of T. cruzi infection controls the parasite replication, inhibits the development of parasite-prone and fibrosis-prone Th2-type immune response, and prevents the development of cardiac abnormalities characteristics of chronic Chagas disease. Our results suggest that the Wnt signaling pathway might be a potential target to prevent the development of T. cruzi-induced cardiomyopathy.

Current knowledge of Chagas-related heart disease among pediatric cardiologists in the United States

Background

Chagas disease is a pathogenic parasitic infection with approximately 8 million cases worldwide and greater than 300,000 cases in the United States (U.S.). Chagas disease can lead to chronic cardiomyopathy and cardiac complications, with variable cardiac presentations in pediatrics making it difficult to recognize. The purpose of our study is to better understand current knowledge and experience with Chagas related heart disease among pediatric cardiologists in the U.S.

Methods

We prospectively disseminated a 19-question survey to pediatric cardiologists via 3 pediatric cardiology listservs. The survey included questions about demographics, Chagas disease presentation and experience.

Results

Of 139 responses, 119 cardiologists treat pediatric patients in the U.S. and were included. Most providers (87%) had not seen a case of Chagas disease in their practice; however, 72% also had never tested for it. The majority of knowledge-based questions about Chagas disease cardiac presentations were answered incorrectly, and 85% of providers expressed discomfort with recognizing cardiac presentations in children. Most respondents selected that they would not include Chagas disease on their differential diagnosis for presentations such as conduction anomalies, myocarditis and/or apical aneurysms, but would be more likely to include it if found in a Latin American immigrant. Of respondents, 87% agreed that they would be likely to attend a Chagas disease-related lecture.

Conclusions

Pediatric cardiologists in the U.S. have seen very few cases of Chagas disease, albeit most have not sent testing or included it in their differential diagnosis. Most individuals agreed that education on Chagas disease would be worth-while.

Advanced Therapies for Ventricular Arrhythmias in Patients With Chagasic Cardiomyopathy: JACC State-of-the-Art Review

Chagas disease is caused by infection from the protozoan parasite Trypanosoma cruzi. Although it is endemic to Latin America, global migration has led to an increased incidence of Chagas in Europe, Asia, Australia, and North America. Following acute infection, up to 30% of patients will develop chronic Chagas disease, with most patients developing Chagasic cardiomyopathy. Chronic Chagas cardiomyopathy is highly arrhythmogenic, with estimated annual rates of appropriate implantable cardioverter-defibrillator therapies and electrical storm of 25% and 9.1%, respectively. Managing arrhythmias in patients with Chagasic cardiomyopathy is a major challenge for the clinical electrophysiologist, requiring intimate knowledge of cardiac anatomy, advanced training, and expertise. Endocardial-epicardial mapping and ablation strategy is needed to treat arrhythmias in this patient population, owing to the suboptimal long-term success rate of endocardial mapping and ablation alone. We also describe innovative approaches to improve acute and long-term clinical outcomes in patients with refractory ventricular arrhythmias following catheter ablation, such as bilateral cervicothoracic sympathectomy and bilateral renal denervation, among others.

Coagulation disorders in Chagas disease: A pathophysiological systematic review and meta-analysis

BACKGROUND

Currently, Chagas disease (CD) constitutes one of the main public health problems in Latin America. However, little is known about potential mechanisms of disease different from cardiac or digestive involvement, such as the coagulation disorders elicited by the parasite persistence in the tissues. The aim of this systematic review was to describe and characterize all the published literature that evaluated the pathophysiological aspects of coagulation disorders in CD.

METHODS

Searches in Medline, EMBASE, and LILACS databases (from inception to July 28th, 2020) were performed. Articles of any language reporting the levels of different coagulation factors/markers or the prevalence of abnormal levels of the mentioned molecules in patients with CD were included. Two reviewers independently selected the studies, extracted the data, and assessed the quality of evidence. Estimates were pooled using random-effects meta-analyses.

RESULTS

Seven studies evaluating a total of 676 participants fulfilled the criteria and were included, while only six were suitable for meta-analyzing (544 participants, 52% men, mean age: 49 ± 8 years). 57.16% of the patients in the meta-analysis had a serological confirmed diagnosis of CD, while 97% of these were in the indeterminate stage of the disease. Patients in the CD group had higher levels of F 1 + 2 (SMD 5.15. 95% CI 1.92, 8.38), PAI-1 (SMD 0.46. 95% CI 0.07; 0.89), and P-selectin (SMD 1.8; 95% CI 0.13-3.47) compared to healthy controls. Furthermore, benznidazole therapy was associated with a reduction in the levels of these biomarkers after treatment.

CONCLUSION

The results of the present study suggest that patients with chronic T. cruzi infection are affected by a potential hypercoagulable state irrespective of the development of cardiac or digestive disease. Furthermore, the reduction in the levels of the coagulation markers after benznidazole therapy may suggest a significant role of the parasite load in the development of these coagulation disorders. There is a scarcity of research assessing the molecular and pathophysiological mechanisms of coagulation disorders in Chagas disease. Further research is needed to assess the benefit of benznidazole therapy on this hypercoagulable state in the long-term, along with its impact on the risk of thromboembolic events in CD patients.

Correlation between Cardiomegaly on Chest X-Ray and Left Ventricular Diameter on Echocardiography in Patients with Chagas Disease

Fundamento

Cardiomegalia pela radiografia de tórax (RXT) é preditor independente de morte em indivíduos com cardiomiopatia crônica da doença de Chagas (CCDC). Contudo, a correlação entre o aumento do índice cardiotorácico (ICT) na RXT e do diâmetro telediastólico do ventrículo esquerdo (DDVE) pela ecocardiografia (ECO) nessa população não está bem definida.

Objetivos

Analisar a relação entre cardiomegalia pela RXT e DDVE pela ECO em pacientes com doença de Chagas (DC) e sua aplicabilidade ao escore de Rassi.

Métodos

Estudo retrospectivo incluiu 63 pacientes ambulatoriais com DC avaliados por RXT e ECO. Cardiomegalia na RXT foi definida como ICT > 0,5. DDVE foi avaliado como variável contínua. Curva ROC foi utilizada para avaliar o potencial do DDVE para identificação de cardiomegalia pela RXT, com ponto de corte definido pela maior somatória de sensibilidade e especificidade.

Resultados

Idade mediana = 61 anos [intervalo interquartil: 48-68], 56% mulheres. CCDC foi identificada em 58 pacientes; 5 tinham a forma indeterminada da DC. Cardiomegalia foi detectada em 28 indivíduos. A área sob a curva ROC do DDVE para identificação de cardiomegalia foi de 0,806 (IC 95%: 0,692-0,919). O ponto de corte ótimo para DDVE foi de 60 mm (sensibilidade = 64%, especificidade = 89%). O uso do DDVE pela ECO em substituição ao ICT pela RXT alterou o escore de Rassi em 14 pacientes, e em 10 deles houve redução do risco presumido.

Conclusão

DDVE pela ECO é parâmetro adequado e com alta especificidade para distinguir entre presença e ausência de cardiomegalia na RXT na DC. (Arq Bras Cardiol. 2021; 116(1):68-74)

Prevalence of Cardiac Arrhythmias and Distal Conduction Disorders in Patients With Chronic Chagas' Disease and Elevated Autoantibodies Against M2 Muscarinic Acetylcholine Receptors

Chagas' disease (ChD) is a parasitic disease endemic to regions of Latin America and with an increasingly global reach. Up to 30% of patients with ChD develop severe dilated cardiomyopathy, ventricular arrhythmias, conduction disorders and/or sudden cardiac death. Autoantibodies against M₂ muscarinic acetylcholine receptors (M₂ mAChR) have been implicated in the pathogenesis of ChD. We sought to understand whether there was an association between anti-M₂ mAChR autoantibody titers in patients with chronic ChD and the presence of distal cardiac conduction disorders or cardiac arrhythmias. We conducted a cross-sectional study in 79 patients from Argentina and Bolivia with chronic ChD without evident structural heart disease. Autoantibody titers were measured using indirect enzyme-linked immunosorbent assay. Elevated anti-M₂ mAChR autoantibody titers were associated with the presence of distal conduction disease but not with cardiac arrhythmias. High anti-M₂ mAChR autoantibody levels could assist with identifying early structural heart disease in patients with chronic ChD.

Chagas Cardiomyopathy as the Etiology of Suspected Coronary Microvascular Disease. A Comparison Study with Suspected Coronary Microvascular Disease of Other Etiologies

BACKGROUND

Chagas disease (CD) as neglected secondary form of suspected coronary microvascular dysfunction (CMD).

OBJECTIVES

Comparison of patients with CMD related to CD (CMD-CE) versus patients with CMD caused by other etiologies (CMD-OE).

METHODS

Of 1292 stable patients referred for invasive coronary angiography to elucidate the hemodynamic pattern and the cause of angina as a cardinal symptom in their medical history, 247 presented normal epicardial coronary arteries and 101 were included after strict exclusion criteria. Of those, 15 had suspected CMD-CE, and their clinical, hemodynamic, angiographic and scintigraphic characteristics were compared to those of the other 86 patients with suspected CDM-OE. Level of significance for all comparisons was p < 0.05.

RESULTS

Patients with suspected CMD-CE showed most anthropometric, clinical, angiographic hemodynamic and myocardial perfusion abnormalities that were statistically similar to those detected in the remaining 86 patients with suspected CMD-OE. LV diastolic dysfunction, expressed by elevated LV end-diastolic pressure was equally found in both groups. However, as compared to the group of CMD-OE the group with CMD-CE exhibited lower left ventricular ejection fraction (54.8 ± 15.9 vs 61.1 ± 11.9, p= 0.049) and a more severely impaired index of regional wall motion abnormalities (1.77 ± 0.35 vs 1.18 ± 0.26, p= 0.02) respectively for the CMD-OE and CMD-CE groups.

CONCLUSION

Chronic Chagas cardiomyopathy was a secondary cause of suspected coronary microvascular disease in 15% of 101 stable patients whose cardinal symptom was anginal pain warranting coronary angiography. Although sharing several clinical, hemodynamic, and myocardial perfusion characteristics with patients whose suspected CMD was due to other etiologies, impairment of LV segmental and global systolic function was significantly more severe in the patients with suspected CMD related to Chagas cardiomyopathy. (Arq Bras Cardiol. 2020; 115(6):1094-1101).

Neglected cardiovascular diseases and their significance in the Global North

Due to increasing global migration, the spectrum of cardiovascular disease (CVD) is changing in developed countries. Up to 3% of migrants arriving in Europe have underlying CVD. Despite their high global prevalence, conditions such as rheumatic heart disease, Chagas disease, endomyocardial fibrosis, tuberculous pericarditis, peripartum cardiomyopathy, and pulmonary hypertension are often under-recognized, and, as a result, neglected in industrialized countries. Many of these conditions, and their causes, are often unfamiliar to the health-care providers in host countries. In this review, we summarize the epidemiology, etiology, clinical presentation, diagnostic work-up, and management of neglected CVDs that have an increasing prevalence in the Global North.

The Case for the Development of a Chagas Disease Vaccine: Why? How? When?

Chagas disease is a major neglected tropical disease, transmitted predominantly by triatomine insect vectors, but also through congenital and oral routes. While endemic in the Americas, it has turned into a global disease. Because of the current drug treatment limitations, a vaccine would represent a major advancement for better control of the disease. Here, we review some of the rationale, advances, and challenges for the ongoing development of a vaccine against Chagas disease. Recent pre-clinical studies in murine models have further expanded (i) the range of vaccine platforms and formulations tested; (ii) our understanding of the immune correlates for protection; and (iii) the extent of vaccine effects on cardiac function, beyond survival and parasite burden. We further discuss outstanding issues and opportunities to move Chagas disease development forward in the near future.

Sudden Cardiac Death Risk Stratification and Prevention in Chagas Disease: A Non-systematic Review of the Literature

Chagas disease is an important public health problem in Latin America. However, migration and globalisation have resulted in the increased presence of Chagas disease worldwide. Sudden cardiac death is the leading cause of death in people with Chagas disease, most often due to ventricular fibrillation. Although more common in patients with documented ventricular arrhythmias, sudden cardiac death can also be the first manifestation of Chagas disease in patients with no previous symptoms or known heart failure. Major predictors of sudden cardiac death include cardiac arrest, sustained and non-sustained ventricular tachycardia, left ventricular dysfunction, syncope and bradycardia. The authors review the predictors and risk stratification score developed by Rassi et al. for death in Chagas heart disease. They also discuss the evidence for anti-arrhythmic drugs, catheter ablation, ICDs and pacemakers for the prevention of sudden cardiac death in these patients. Given the widespread global burden, understanding the risk stratification and prevention of sudden cardiac death in Chagas disease is of timely concern.

Chagas disease reactivation in rheumatologic patients: association with immunosuppressive therapy and humoral response

Evidence for Chagas disease reactivation (CDR) in rheumatologic patients under rheumatologic treatments (RTs) is scarce. To screen and follow-up patients with rheumatic diseases and concomitant Chagas disease under RT to detect CDR and to describe a possible relationship between CDR and specific RT. An observational, longitudinal, prospective, consecutive study was carried out between 2018 and 2020. Included patients were evaluated during the follow-up for clinical and laboratorial manifestations of CDR. Direct blood parasitological examination (Strout method) and polymerase chain reaction (PCR) were employed to diagnose CDR. The dynamic of anti-T. cruzi-specific antibodies was also assessed by IHA and ELISA (total IgG and Anti-SAPA). Fifty-one patients were included (86% women). Rheumatoid arthritis was the predominant disease (57%). Classic DMARDs (86.3%) and corticosteroids (61%) were the most frequent RT. CDR was developed in 6 patients (11.7%), exhibiting both positive Strout and PCR. Symptomatic reactivation of CD (fever, asthenia, arthralgias, myalgias) occurred in two patients who had previously been diagnosed with it. Regardless of the different RT, all patients who experienced CDR had previously received more than ≥ 20 mg/day of prednisone equivalent. Despite immunosuppression, patients with CDR exhibited increased levels of specific anti-T. cruzi and anti-SAPA antibodies, which decreased after anti-parasitic treatment. CDR is possible in rheumatologic patients, especially after receiving high doses of corticosteroids. Since CDR symptoms may mimic rheumatic disease activity, monitoring of Chagas disease is highly recommended before, during and after immunosuppression. Key Points • Chagas disease reactivation (CDR) in the context of rheumatological treatment was associated to high doses of corticosteroids. • CDR was associated with an increase in anti-T. cruzi antibodies despite the immunosuppressive treatment. • Suspecting and anticipating CDR is mandatory in this patient population to diagnose and treat it.

Recognition and screening for Chagas disease in the USA

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is a public health concern, mainly among countries in South and Central America. However, despite the large number of immigrants from endemic countries living in the USA, awareness of CD is poor in the medical community, and therefore it is significantly underdiagnosed. To avoid the catastrophic cardiac complications of CD and to prevent maternal-fetal transmission, widespread educational programs highlighting the need for diagnosis are urgently needed.