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BackgroundIdiopathic dilated cardiomyopathy (IDCM) myocardial inflammation may be associated with external triggering factors such as infectious agents. Here, we searched if moderate/severe heart transplantation rejection is related to the presence of myocardial inflammation in IDCM explanted hearts, associated with microbial communities.MethodReceptor myocardial samples from 18 explanted hearts were separated into groups according to post-transplant outcome: persistent moderate rejection (PMR; n = 6), moderate rejection (MR; n = 7) that regressed after pulse therapy, and no rejection (NR; n = 5)/light intensity rejection. Inflammation was quantified through immunohistochemistry (IHC), and infectious agents were evaluated by IHC, molecular biology, in situ hybridization technique, and transmission electron microscopy (TEM).ResultsNR presented lower numbers of macrophages, as well as B cells (p = 0.0001), and higher HLA class II expression (p ≤ 0.0001). PMR and MR showed higher levels of Mycoplasma pneumoniae (p = 0.003) and hepatitis B core (p = 0.0009) antigens. NR presented higher levels of parvovirus B19 (PVB19) and human herpes virus 6 (HHV6) and a positive correlation between Borrelia burgdorferi (Bb) and enterovirus genes. Molecular biology demonstrated the presence of M. pneumoniae, Bb, HHV6, and PVB19 genes in all studied groups. TEM revealed structures compatible with the cited microorganisms.ConclusionsThis initial study investigating on infectious agents and inflammation in the IDCM explanted hearts showed that the association between M. pneumoniae and hepatitis B core was associated with a worse outcome after HT, represented by MR and PMR, suggesting that different IDCM microbial communities may be contributing to post-transplant myocardial rejection.

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.

BackgroundAbdominal aortic aneurysm (AAA) is a pathological enlargement of infrarenal aorta close to the aortic bifurcation, and it is an important cause of mortality in the elderly. Therefore, the biomarker identification for early diagnosis is of great interest for clinical benefit. It is known that microRNAs (miRNAs) have important roles via target genes regulation in many diseases. This study aimed to identify miRNAs and their target genes involved in the pathogenesis of AAA.MethodsTissue samples were obtained from patients who underwent AAA surgery and from organ donors (control group). Quantitative PCR Array was applied to assess 84 genes and 384 miRNAs aiming to identify differentially expressed targets (AAA n = 6, control n = 6), followed by validation in a new cohort (AAA n = 18, control n = 6) by regular qPCR. The functional interaction between validated miRNAs and target genes was performed by the Ingenuity Pathway Analysis (IPA) software.ResultsThe screening cohort assessed by PCR array identified 10 genes and 59 miRNAs differentially expressed (≥2-fold change, pConclusionPaired interactions of differentially expressed ALOX5, PTGIS, CX3CL1 genes, and miR-193b-3p, 125b-5p, 150-5p revealed a potentially significant role of the eicosanoid synthesis and metalloproteinase/TIMP pathways in the AAA pathogenesis.

Background: Archaeal genes present in Trypanosoma cruzi may represent symbionts that would explain development of heart failure in 30% of Chagas disease patients. Extracellular vesicles in peripheral blood, called exosomes (< 0.1 μm) or microvesicles (>0.1 μm), present in larger numbers in heart failure, were analyzed to determine whether they are derived from archaea in heart failure Chagas disease.Methods: Exosomes and microvesicles in serum supernatant from 3 groups were analyzed: heart failure Chagas disease (N = 26), asymptomatic indeterminate form (N = 21) and healthy non-chagasic control (N = 16). Samples were quantified with transmission electron microscopy, flow cytometer immunolabeled with anti-archaemetzincin-1 antibody (AMZ 1, archaea collagenase) and probe anti-archaeal DNA and zymography to determine AMZ1 (Archaeal metalloproteinase) activity.Results: Indeterminate form patients had higher median numbers of exosomes/case vs. heart failure patients (58.5 vs. 25.5, P < 0.001), higher exosome content of AMZ1 antigens (2.0 vs. 0.0; P < 0.001), and lower archaeal DNA content (0.2 vs. 1.5, P = 0.02). A positive correlation between exosomes and AMZ1 content was seen in indeterminate form (r = 0.5, P < 0.001), but not in heart failure patients (r = 0.002, P = 0.98). Higher free archaeal DNA (63.0 vs. 11.1, P < 0.001) in correlation with exosome numbers (r = 0.66, P = 0.01) was seen in heart failure but not in indeterminate form (r = 0.29, P = 0.10). Flow cytometer showed higher numbers of AMZ1 microvesicles in indeterminate form (64 vs. 36, P = 0.02) and higher archaeal DNA microvesicles in heart failure (8.1 vs. 0.9, P < 0.001). Zymography showed strong% collagenase activity in HF group, mild activity in IF compared to non-chagasic healthy group (121 ± 14, 106 ± 13 and 100; P < 0.001).Conclusions: Numerous exosomes, possibly removing and degrading abnormal AMZ1 collagenase, are associated with indeterminate form. Archaeal microvesicles and their exosomes, possibly associated with release of archaeal AMZ1 in heart failure, are future candidates of heart failure biomarkers if confirmed in larger series, and the therapeutic focus in the treatment of Chagas disease.

Background: Studies have pointed out a higher mortality after coronary artery bypass surgery (CABG) in patients with stent. Objective: To evaluate inflammatory markers in peripheral blood cells and in coronary artery tissue samples obtained during CABG in patients with stent compared to controls. Methods: The case series consisted of two groups, one with previous stent implantation (n = 41) and one control (n = 26). The expression of the LIGHT, IL-6, ICAM, VCAM, CD40, NFKB, TNF, IFNG genes was analyzed in peripheral blood cells collected preoperatively. The coronary artery was evaluated for: interleukin-6, ICAM, VCAM, CD40, NFKB, TNF-alpha and IFN-gamma by immunohistochemistry. A total of 176 tissue samples were grouped for analysis in: A1- arteries with stent (n = 38); A2- native arteries from patients with stent in another artery (n = 68); and A3- arteries without stent from controls undergoing routinely CABG surgery (n = 70). A significance level of 0.05 was adopted. Results: Patients with stent showed higher TNF (p = 0.03) and lower CD40 gene expression (p = 0.01) in peripheral blood cells than controls without stent. In coronary artery samples, the TNF-alpha protein staining was higher in the group A1, not only in the intima-media layer (5.16 ± 5.05 vs 1.90 ± 2.27; p = 0.02), but also in the adipose tissue (6.69 ± 3.87 vs 2.27 ± 4.00; p < 0.001). Furthermore, group A1 had a higher interleukin-6 protein staining in adipose tissue than group A3 (p = 0.04). Conclusion: We observed a persistently higher systemic TNF expression associated with exacerbated TNF-alpha and interleukin-6 local production in patients with stents. This finding may contribute to a worse clinical outcome. Resumo Fundamento: Estudos relataram maior mortalidade após cirurgia de revascularização miocárdica (RVM) em pacientes com stent. Objetivo: Avaliar marcadores inflamatórios em células do sangue periférico e em amostras de tecido de artéria coronária obtidas durante cirurgia de RVM em pacientes com stent e compará-los aos de controles. Métodos: A casuística consistiu de dois grupos, um com prévia implantação de stent (n = 41) e um controle (n = 26). Em células do sangue periférico coletadas no pré-operatório, analisou-se a expressão dos seguintes genes: LIGHT, IL-6, ICAM, VCAM, CD40, NFKB, TNF, IFNG. A artéria coronária foi avaliada por imuno-histoquímica para: interleucina-6, ICAM, VCAM, CD40, NFKB, TNF-alfa e IFN-gama. No total, 176 amostras de tecido arterial coronariano foram assim agrupadas para análise: A1- artérias com stent (n = 38); A2- artérias nativas de paciente com stent em outra artéria (n = 68); e A3- artérias de controles sem stent submetidos a cirurgia de RVM de rotina (n = 70). Adotou-se o nível de significância de 0,05. Results: Pacientes com stent apresentaram maior expressão do gene TNF (p = 0,03) e menor do CD40 (p = 0,01) em células do sangue periférico do que controles sem stent. Nas amostras de artéria coronária, a coloração da proteína TNF-alfa foi maior no grupo A1, não apenas na camada médio-intimal (5,16 ± 5,05 vs 1,90 ± 2,27; p = 0,02), mas também no tecido adiposo (6,69 ± 3,87 vs 2,27 ± 4,00; p < 0,001). Além disso, o grupo A1 apresentou maior coloração para interleucina-6 no tecido adiposo do que o grupo A3 (p = 0,04). Conclusão: Observou-se expressão sistêmica de TNF persistentemente maior em associação com produção local exacerbada de TNF-alfa e IL-6 em pacientes com stent. Isso pode contribuir para pior desfecho clínico.

A study with transmission electron microscopy of mycoplasma-contaminated HeLa cells using five cell donors referred to as donors A, B, C, D and E, observations are herein presented. Experiments performed with cells from donors B, C and D, revealed the presence of Mycoplasma hyorhinis after PCR and sequencing experiments. Bacteria probably originated from a cytoplasm with compacted tiny granular particles replacing the normal cytosol territories, or from the contact with the cytoplasm through a clear semi-solid material. The compact granularity (CG) of the cytoplasm was crossed by stripes of smooth and rough endoplasmic reticulum cisternae. Among apparently normal mitochondria, it was noted, in variable proportions, mitochondria with crista-delimited lucent central regions that expand to and occupied the interior of a crista-less organelle, which can undergo fission. Other components of the scenarios of mycoplasma-induced cell demolition are villus-like structures with associated 80-200 nm vesicles and a clear, flexible semi-solid, process-sensitive substance that we named jam-like material. This material coated the cytoplasmic surface, its recesses, irregular protrusions and detached cytoplasmic fragments. It also cushioned forming bacteria. Cyst-like structures were often present in the cytoplasm. Cells, mainly apoptotic, exhibiting ample cytoplasmic sectors with characteristic net-like profile due to adjoined vacuoles, as well as ovoid or elongated profiles, consistently appeared in all cells from the last four cell donors. These cells were named “modified host cells” because bacteria arose in the vacuoles. The possibility that, in some samples, there was infection and/or coinfection of the host cell by another organism(s) cannot be ruled out.

Background Clinical and experimental conflicting data have questioned the relationship between infectious agents, inflammation and dilated cardiomyopathy (DCM). Objectives The aim of this study was to determine the frequency of infectious agents and inflammation in endomyocardial biopsy (EMB) specimens from patients with idiopathic DCM, explanted hearts from different etiologies, including Chagas' disease, compared to donated hearts. Methods From 2008 to 2011, myocardial samples from 29 heart donors and 55 patients with DCMs from different etiologies were studied (32 idiopathic, 9 chagasic, 6 ischemic and 8 other specific etiologies). Inflammation was investigated by immunohistochemistry and infectious agents by immunohistochemistry, molecular biology, in situ hybridization and electron microscopy. Results There were no differences regarding the presence of macrophages, expression of HLA class II and ICAM-I in donors and DCM. Inflammation in Chagas' disease was predominant. By immunohistochemistry, in donors, there was a higher expression of antigens of enterovirus and Borrelia , hepatitis B and C in DCMs. By molecular biology, in all groups, the positivity was elevated to microorganisms, including co-infections, with a higher positivity to adenovirus and HHV6 in donors towards DCMs. This study was the first to demonstrate the presence of virus in the heart tissue of chagasic DCM. Conclusions The presence of inflammation and infectious agents is frequent in donated hearts, in the myocardium of patients with idiopathic DCM, myocardial dysfunction related to cardiovascular diseases, and primary and secondary cardiomyopathies, including Chagas' disease. The role of co-infection in Chagas' heart disease physiopathology deserves to be investigated in future studies.

Introduction: The biomechanical failure properties and histological composition of the human nonaneurysmal aorta were studied. Methods: Twenty-six human aortas were harvested from fresh cadavers at autopsy. A total of 153 circumferentially oriented strips were obtained from the aortas for biomechanical and histological studies. Results: The failure load (6.18 ± 2.03 vs. 4.85 ± 2.04 N; p = 0.001), failure tension (19.88 ± 9.05 vs. 14.53 ± 7 N/cm; p = 0.001), failure strain (0.66 ± 0.31 vs. 0.49 ± 0.25; p = 0.003) and amount of elastic fibers (19.39 ± 15.57 vs. 14.06 ± 9.5%; p = 0.011) were all significantly higher for the thoracic than the abdominal aorta. There was a significant negative correlation between age and failure load (R = -0.35; p < 0.0001), failure stress (R = -0.63; p < 0.0001), failure tension (R = -0.52; p < 0.0001) and failure strain (R = -0.8; p < 0.0001). Male aortas had a higher failure load and failure tension than female aortas. Conclusion: The thoracic aorta has a higher strength and elasticity than the abdominal aorta. The elderly have weaker and stiffer aortas than the young. Male aortas are stronger than female aortas.

Background The etiology of myxomatous mitral valve degeneration (MVD) is not fully understood and may depend on time or environmental factors for which the interaction of infectious agents has not been documented. The purpose of the study is to analyze the effect of Mycoplasma pneumoniae (Mp), Chlamydophila pneumoniae (Cp) and Borrelia burgdorferi (Bb) on myxomatous mitral valve degeneration pathogenesis and establish whether increased in inflammation and collagen degradation in myxomatous mitral valve degeneration etiopathogenesis. Methods An immunohistochemical test was performed to detect the inflammatory cells (CD20, CD45, CD68) and Mp, Bb and MMP9 antigens in two groups. The in situ hybridization was performed to detect Chlamydophila pneumoniae and the bacteria study was performed using transmission electron microscopy. Group 1 (n = 20), surgical specimen composed by myxomatous mitral valve degeneration, and group 2 (n = 20), autopsy specimen composed by normal mitral valve. The data were analyzed using SigmaStat version 20 (SPSS Inc., Chicago, IL, USA). The groups were compared using Student’s t test, Mann-Whitney test. A correlation analysis was performed using Spearman’s correlation test. P values lower than 0.05 were considered statistically significant. Results By immunohistochemistry, there was a higher inflammatory cells/mm2 for CD20 and CD45 in group 1, and CD68 in group 2. Higher number of Mp and Cp antigens was observed in group 1 and more Bb antigens was detected in group 2. The group 1 exhibited a positive correlation between the Bb and MVD percentage, between CD45 and Mp, and between MMP9 with Mp. These correlations were not observed in the group 2. Electron microscopy revealed the presence of structures compatible with microorganisms that feature Borrelia and Mycoplasma characteristics. Conclusions The presence of infectious agents, inflammatory cells and collagenases in mitral valves appear to contribute to the pathogenesis of MVD. Mycoplasma pneumoniae was strongly related with myxomatous mitral valve degeneration. Despite of low percentage of Borrelia burgdorferi in MD group, this agent was correlated with myxomatous degeneration and this may occour due synergistic actions between these infectious agents likely contribute to collagen degradation. Electronic supplementary material The online version of this article (doi:10.1186/s12879-017-2387-8) contains supplementary material, which is available to authorized users.

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Background: We searched for any relationship between Chlamydophila pneumoniae, Mycoplasma pneumoniae, matrix metalloproteinase 9 (MMP-9), and tissue inhibitor of metalloproteinase 1 (TIMP-1) in aneurysmatic atherosclerotic lesions, and whether this relationship differed from that in atherosclerotic nonaneurysmatic lesions. Methods: Twenty-eight tissue samples paired by age and sex were grouped as follows: group 1 included 14 nonaneurysmal atherosclerotic fragments obtained from abdominal aortas collected from necropsies; group 2 included 14 aneurysmatic atherosclerotic aortic fragments obtained from patients during corrective surgery. Immunohistochemistry reactions were evaluated for C pneumoniae, M pneumoniae, MMP-9, and TIMP-1 antigens. Both groups were compared using the ManneWhitney test, and the correlations among variables were obtained using the Spearman correlation test. P � 0.05 was considered statistically significant. Results: C pneumoniae and M pneumoniae antigens were detected in 100% of cases. A higher amount of C pneumoniae (P ¼ 0.005), M pneumoniae (P ¼ 0.002), and MMP-9 (P ¼ 0.021) was found in adventitia of group 2 with aneurysm. A positive correlation was found in the aneurysm group, as follows: intima C pneumoniae versus adventitia thickness (r ¼ 0.70; P ¼ 0.01), media CpneumoniaeversusadventitiaCpneumoniae(r ¼0.75;P ¼0.002),intimaCpneumoniaeversus media C pneumoniae (r ¼ 0.8; P ¼ 0.00), and adventitia C pneumoniae versus intima M pneumoniae (r ¼ 0.54; P ¼ 0.05); negative correlations were as follows: adventitia thickness andadventitia M pneumoniae (r ¼� 0.65; P ¼ 0.01), media MMP-9 and media thickness (r ¼� 0.55; P ¼ 0.04), TIMP-1mediaversus adventitiaC pneumoniae(r ¼� 0.8 6;P ¼0.00), andTIMP-1 media versusM pneumoniae intima (r ¼� 0.67; P ¼ 0.03). Nonaneurysmal atherosclerotic group 1 results are as follows: adventitiaC pneumoniaeversus TIMP-1 media (r ¼ 0.75;P ¼ 0.01) and mediaC pneumoniae and adventitia C pneumoniae (r ¼ 0.59; P ¼ 0.03). Conclusions: The present work favors a role for coinfection of both M pneumoniae and C pneumoniae in the development of aortic atherosclerotic aneurysm, with increased adventitial inflammation, inhibition of TIMP-1 activity, and increased collagen degradation.

Purpose To test the hypothesis that ruptured abdominal aortic aneurysms (AAA) are globally weaker than unruptured ones. Methods Four ruptured and seven unruptured AAA specimens were harvested whole from fresh cadavers during autopsies performed over an 18-month period. Multiple regionally distributed longitudinally oriented rectangular strips were cut from each AAA specimen for a total of 77 specimen strips. Strips were subjected to uniaxial extension until failure. Sections from approximately the strongest and weakest specimen strips were studied histologically and histochemically. From the load-extension data, failure tension, failure stress and failure strain were calculated. Rupture site characteristics such as location, arc length of rupture and orientation of rupture were also documented. Results The failure tension, a measure of the tissue mechanical caliber was remarkably similar between ruptured and unruptured AAA (group mean±standard deviation of within-subject means: 11.2±2.3 versus 11.6±3.6 N/cm; p =0.866 by mixed model ANOVA). In post-hoc analysis, there was little difference between the groups in other measures of tissue mechanical caliber as well such as failure stress (95±28 versus 98±23 N/cm 2 ; p =0.870), failure strain (0.39±0.09 versus 0.36±0.09; p =0.705), wall thickness (1.7±0.4 versus 1.5±0.4 mm; p =0.470) , and % coverage of collagen within tissue cross section (49.6±12.9% versus 60.8±9.6%; p =0.133). In the four ruptured AAA, primary rupture sites were on the lateral quadrants (two on left; one on left-posterior; one on right). Remarkably, all rupture lines had a longitudinal orientation and ranged from 1 to 6 cm in length. Conclusion The findings are not consistent with the hypothesis that ruptured aortic aneurysms are globally weaker than unruptured ones.

Gap junction connexin-43 (Cx43) molecules are responsible for electrical impulse conduction in the heart and are affected by transforming growth factor-beta (TGF-beta). This cytokine increases during Trypanosoma cruzi infection, modulating fibrosis and the parasite cell cycle. We studied Cx43 expression in cardiomyocytes exposed or not to TGF-beta T. cruzi, or SB-431542, an inhibitor of TGF-beta receptor type I (ALK-5). Cx43 expression was also examined in hearts with dilated cardiopathy from chronic Chagas disease patients, in which TGF-beta signalling had been shown previously to be highly activated. We demonstrated that TGF-beta treatment induced disorganised gap junctions in non-infected cardiomyocytes, leading to a punctate, diffuse and non-uniform Cx43 staining. A similar pattern was detected in T. cruzi-infected cardiomyocytes concomitant with high TGF-beta secretion. Both results were reversed if the cells were incubated with SB-431542. Similar tests were performed using human chronic chagasic patients and we confirmed a down-regulation of Cx43 expression, an altered distribution of plaques in the heart and a significant reduction in the number and length of Cx43 plaques, which correlated negatively with cardiomegaly. We conclude that elevated TGF-beta levels during T. cruzi infection promote heart fibrosis and disorganise gap junctions, possibly contributing to abnormal impulse conduction and arrhythmia that characterise severe cardiopathy in Chagas disease.

Myocyte diameter, fractional area of collagen, intensity of myocarditis and parasite persistence (explored by immunohistochemistry and PCR) were evaluated in serial sections of endomyocardial biopsies from 29 outpatients with chronic chagasic cardiopathy. The patients, 25 males and four females with a mean (S.D.) age of 43 (9) years, were subsequently followed up for 3-2861 days (median=369 days). During this follow-up, 16 (55%) of the patients died. The biopsies revealed myocarditis in 25 (86%) of the patients and high-grade myocarditis in 14 (56%). Although immunohistochemistry failed to demonstrate Trypanosoma cruzi antigens in any of the samples, five (33%) of the 15 biopsies successfully tested in the PCR-based assay for T. cruzi DNA were found positive, indicating parasite persistence. There was a significant positive association between myocardial parasite persistence and high-grade myocarditis (P=0.014); five (71%) of the seven endomyocardial biopsies with high-grade myocarditis that were successfully tested in the PCR assays showed persistent T. cruzi DNA. The survival time of the patients was not, however, found to be significantly associated with myocardial parasite persistence, any of the morphometric measurements taken, or the presence or intensity of myocarditis.

Human chronic Chagas disease cardiomyopathy (CCC) is an inflammatory-dilated cardiomyopathy occurring years after infection by the protozoan Trypanosoma cruzi. The heart inflammatory infiltrate in CCC shows a 2:1 predominance of CD8(+) in relation to CD4(+) T cells, with a typical Th1-type cytokine profile. However, in vitro expansion of infiltrating T cells from heart biopsy-derived fragments with interleukin-2 (IL-2) and phytohaemagglutinin leads to the outgrowth of CD4(+) over CD8(+) T cells. We hypothesized that survival cytokines, such as IL-2, IL-7 and IL-15 might be differentially involved in the growth and maintenance of heart-infiltrating and peripheral CD8(+) T cells from CCC patients. We found that IL-7 and IL-15 were superior to IL-2 in the expansion and viability of CD8(+) T cells from both PBMC and heart-infiltrating T-cell lines from CCC patients, and the combination of the three cytokines showed synergic effects. Heart-infiltrating CD8(+) T cells showed higher expression of both IL-15R alpha and gamma(c) chain than CD4(+) T cells, which may explain the improvement of CD8(+) T-cell growth in the presence of IL-2 + IL-7 + IL-15. Immunohistochemical identification of IL-15 and the higher mRNA expression of IL-15R alpha, IL-7 and gamma(c) chain in CCC heart tissues compared with control individuals indicate in situ production of survival cytokines and their receptors in CCC hearts. Together, our results suggest that local production of IL-7 and IL-15 may be associated with the maintenance and predominance of CD8(+) T cells, the cells effecting tissue damage in CCC hearts.

American trypanosomiasis (Chagas' disease [CD]) caused by Trypanosoma cruzi is endemic in Latin America, where it is one of the leading causes of death. The involvement of the heart is crucial in the patients' prognosis. Besides lymphocytic myocarditis, cardiomyopathy is associated with several degrees of myocardial fibrosis (MF). Myocardial delayed enhancement by cardiac magnetic resonance (CMR) has been considered the most accurate method to detect MF in ischemic and nonischemic cardiomyopathy, including Chagas' heart disease. Additionally, CMR offers a wide variety of imaging tools to evaluate in detail morphology, the function and other tissue characterization abilities, such as detection of edema and fat. The present article aims to discuss the current clinical applicability of CMR to evaluate CD. We also discuss its future as a screening tool for very early myocardial involvement, which would allow the investigation of new therapeutic methods with potential influence in the natural history of CD.

An emerging clinical entity that reproduces clinical manifestations similar to those observed in Lyme disease (LD) has been recently under discussion in Brazil. Due to etiological and laboratory particularities it is named LD-like syndrome or LD imitator syndrome. The condition is considered to be a zoonosis transmitted by ticks of the genus Amblyomma, possibly caused by interaction of multiple fastidious microorganisms originating a protean clinical picture, including neurological, osteoarticular and erythema migrans-like lesions. When peripheral blood of patients with LD-like syndrome is viewed under a dark-field microscope, mobile uncultivable spirochete-like bacteria are observed. PCR carried out with specific or conservative primers to recognize Borrelia burgdorferi sensu stricto or the genus Borrelia has been negative in ticks and in biological samples. Two different procedures, respectively involving hematoxylin and eosin staining of cerebrospinal fluid and electron microscopy analysis of blood, have revealed spirochetes not belonging to the genera Borrelia, Leptospira or Treponema. Surprisingly, co-infection with microorganisms resembling Mycoplasma and Chlamydia was observed on one occasion by electron microscopy analysis. We discuss here the possible existence of a new tick-borne disease in Brazil imitating LD, except for a higher frequency of recurrence episodes observed along prolonged clinical follow-up.

Mycoplasma pneumoniae (MP) and Chlamydophila pneumoniae (CP) antigens are encountered in complicated atheromas and may be implicated in the diversity of atherosclerotic lesions. Mycoplasma can downregulate the immune system, altering levels of inflammation, which may favor the proliferation of other co-infectious agents. In the present study we analyze whether initially stable human atheromas exhibit different ratios of MP/CP antigens compared to ongoing atheromatous lesions. Two groups were examined for the presence of inflammatory cells, macrophages, growth factors and infectious agents: Group I (GI), n=16, early stable atheromas,4 CD68(+) macrophages/400 x field, showing a normal distribution and a fibrous cap; Group II (GII), n=14, growing atheromas,or =4 CD68+ cells/400 x field, lacking a fibrous cap, showing a non-normal macrophage distribution. The amounts of CP (but not MP) antigens and lymphocytes in GI were significantly lower than in GII. MP/CP ratios were higher in GI. MP correlated with CP and PDGFB in GI (r=0.79 and r=0.83, p0.001), but not in GII (r=-0.4 and r=-0.08, p=0.81). MP and CP antigens are already present in early atheromas, and a higher MP/CP ratio correlates with increased growth factors, lower inflammation and plaque stability.

In the primary form of pulmonary hypertension (PH), the involvement of inflammation in the physiopathology of the vascular lesions is well established. Its role in secondary PH is yet to be investigated. We quantified the inflammatory cells on the walls of peripheral pulmonary arteries from patients with congenital heart shunts.Twenty-six lung biopsies from patients with increased pulmonary flow and 10 lung fragments from control participants were examined. B-lymphocytes (CD20), T-lymphocytes (CD3), recently recruited macrophages (MAC387) and granulocytes (CD15) were quantified by area of the adventitia in arteries50 microm. An index of inflammatory cells infiltrating the medial and intimal layers was also determined.There was no difference in the sum of densities of adventitial inflammatory cells between the groups. A prevalence of MAC387-labeled cells was detected in the PH group and of CD3-labeled cells in the controls. There was a lower density of T-lymphocytes in the PH group (P.004). Patients with intimal proliferative lesions showed prevalence of MAC387-labeled cells (P=.004). PH participants showed a higher index of MAC387-labeled cells infiltrating the arterial medial and intimal layers (P.001).The predominance of recently recruited macrophages in the PH group is compatible with ongoing inflammatory reaction in the arterial walls. This could be related to the pathogenesis of the vascular lesions, as a consequence of cytokines produced by the inflammatory cells. The smaller number of adventitial T-lymphocytes in patients with congenital shunts can reflect an impairment of their immune response.

In the present review we have summarized remarkable historical data on Chagas' disease studies putting special emphasis on histopathological findings and pathogenetic theories as well as recent discoveries based on the use of advanced modern technologies in pathology and immunology. A unified theory that links almost all of these findings is proposed. Chronic cardiac Chagas' disease represents the result of a close interaction between the host and the parasite, causing different clinical pictures: patients with an efficient immune response may adequately circumvent the parasitic infection and the individual will develop the indeterminate form. Deficient immune response of the host and/or a high initial parasitemia favor an immune imbalance that might lead to development of a permanent inadequate immunological response against the parasite. The inflammatory response, which is probably recurrent, undergoing periods of more accentuated exacerbation, is most likely responsible for progressive neuronal damage, microcirculatory alterations, heart matrix deformations and consequent organ failure.

The development and progression of pulmonary hypertension lesions involve continuous remodeling of the arterial wall, including the extracellular matrix components. The integrity of the internal elastic lamina may represent a barrier to cell migration and formation of intimal proliferative lesions. Some patients with congenital cardiac shunts develop precocious intimal occlusive lesions,whereas others evolve with isolated medial hypertrophy. We studied the 2-D and 3-D morphology of the internal elastic lamina of peripheral pulmonary arteries to search for any difference regarding the type of histological lesion. Fifteen lung biopsies collected for diagnostic purposes from patients with congenital shunts and 6 control lungs (mean ages, 15.8 and 14.7 mo) were studied using the confocal laser scanning microscope, under predetermined conditions of laser intensity, brightness and contrast. We measured the thickness of the internal elastic lamina and determined the number of gaps and projections of elastic tissue towards the medial and intimal layers. The mean internal elastic lamina thickness was significantly higher in arteries from cases with isolated medial hypertrophy when compared with controls and to those with proliferative lesions (P.05). The number of gaps of the internal elastic lamina was higher in arteries100 micro m in diameter from the group with intimal lesions when compared to the cases presenting with isolated hypertrophy, but did not differ from the controls. There was a positive linear correlation between the external arterial diameter and the thickness of the internal elastic lamina (r =.74, P.001) in cases presenting isolated medial hypertrophy. The increased thickness and smaller number of gaps of the internal elastic lamina may act as a barrier that prevents smooth muscle cell migration in patients with pulmonary hypertension without intimal proliferative lesions. On the other hand, a greater number of gaps does not represent, by itself, unrestrained migration, because controls also showed fenestrated laminae.

Background: The ventricles of the normal heart are virtually devoid of atrial natriuretic peptide (ANP). Although ANP occurs in ventricles submitted to elevated wall stress, it is not clear whether ANP expression is affected by myocarditis. We investigated the immunohistochemical expression of ANP in chronic chagasic cardiomyopathy, an inflammatory cardiomyopathy caused by infection with the protozoan Trypanosoma cruzi. Methods: Necropsy samples from the left and right ventricles of 16 patients exhibiting chronic chagasic cardiomyopathy were evaluated for myocarditis, fibrosis, T. cruzi parasites and ANP immunoreactivity. The diameters of 50 myocytes per sample were measured. Results: ANP was present in myocytes of the subendocardial region in 13/16 (81.3%) left and 10/16 (62.5%) right ventricular samples (P=0.25). Myocytes present in the inflammatory foci, near the infiltrating inflammatory cells but distant from the subendocardial region, did not express ANP. Trypanosoma cruzi parasites exhibited intense immunoreactivity for ANP. The mean myocyte diameter and the incidence of myocarditis, fibrosis, and T. cruzi parasites was similar between the left and right ventricular samples. No statistical differences were found between the ANP-positive and ANP-negative cases. Conclusions: In chronic chagasic cardiomyopathy, both ventricles exhibit hypertrophy, fibrosis and ANP in the subendocardial region. The inflammatory infiltrate does not induce ANP expression in the myocytes. Regional stress but not myocarditis itself, is probably responsible for ventricular ANP expression in myocarditis.

Cardiac dysfunction with progressive fibrosis is a hallmark of Chagas disease. To evaluate the involvement of transforming growth factor (TGF)-beta1 in this disease, TGF-beta1 levels in patients were measured at 3 stages: asymptomatic indeterminate (IND), cardiac with no or slight heart dysfunction (Card 1), and cardiac with moderate or severe heart dysfunction (Card 2). All patients had significantly higher circulating levels of TGF-beta1 than did healthy persons, and 27% of patients in the Card 1 group had higher TGF-beta1 levels than did patients in the IND group. Immunohistochemical analysis of cardiac biopsy specimens showed strong fibronectin staining in the extracellular matrix and staining for phosphorylated Smad 2 (activation of the TGF-beta1 signaling pathway) in cell nuclei. The higher levels of latent TGF-beta1 observed in patients with myocardiopathy, together with intracellular activation of the TGF-beta1 pathway and tissue fibrosis, suggest that TGF-beta1 plays an important role in Chagas disease. TGF-beta1 may represent a new target for preventive and curative treatments of Chagas disease.

OBJECTIVE: To verify the possible role of adventitial inflammation in atherosclerotic plaque vulnerability and coronary artery remodelling. METHODS: We compared the mean numbers of lymphocytes in the adventitia and in the plaque of ruptured thrombosed and stable equi-stenotic coronary segments of 34 patients who died due to acute myocardial infarction. We also analysed adventitial microvessels, adventitial fibrosis and the external elastic membrane. RESULTS: In the adventitia, the numbers of lymphocytes and microvessels/mm2 were 69.5±88.3 and 60.9± 32.1 in culprit lesions and 16.4 ± 21.1 and 44.3±16.1 in stable lesions (p

Aortic Valve Stenosis (AVS) has been explained as an atherosclerotic process of the valve as they often exhibit inflammatory changes with infiltration of macrophages, T lymphocytes and lipid infiltration. The present study investigated whether the bacteria Chlamydia pneumoniae (CP) and Mycoplasma pneumoniae (MP), detected previously in atherosclerotic plaques, are also present in AVS. Ten valves surgically removed from patients with AVS were analyzed by immunohistochemistry, in situ hybridization, and electron microscopy. The mean and standard deviation of the percentage areas occupied by CP antigens and MP - DNA were respectively 6.21 +/- 5.41 and 2.27 +/- 2.06 in calcified foci; 2.8 +/- 3.33 and 1.78+/- 3.63 in surrounding fibrotic areas, and 0.21 +/- 0.17 and 0.12 +/- 0.13 in less injured parts of the valve. There was higher amount of CP and MP in the calcified foci and in the surrounded fibrosis than in more preserved valvular regions. In conclusion, the fact that there were greater amounts of CP and MP in calcification foci of AVS favors the hypothesis that AS is not an inevitable degenerative process due to aging, but rather that it may be a response to the presence of these bacteria, similarly to the morphology detected in atherosclerosis damage. Estenose da Valva Aórtica (EVA) tem sido considerada como um processo aterosclerótico das valvas pois elas freqüentemente exibem alterações inflamatórias com acúmulo de macrófagos e linfócitos T, bem como infiltração de lípides. O presente estudo investigou se as bactérias Chlamydia pneumoniae (CP) e Mycoplasma pneumoniae (MP), detectadas previamente em placas ateroscleróticas, estavam presentes na EVA. Dez valvas removidas cirúrgicamente de pacientes com EVA foram analisadas pela imunohistoquímica, hibridização in situ e microscopia eletrônica. A média e desvio padrão das porcentagens de área ocupadas por antígenos de CP e de DNA do MP foram respectivamente de 6,21 +/- 5,41 e 2,27 +/- 2,06 nos focos de calcificação; 2,8 +/- 3,33 e 1,78+/- 3,063 nas áreas de fibrose ao redor e 0,21 +/- 0,17 e 0,12 +/- 0,13 nas regiões menos lesadas da válvula. Houve uma maior quantidade de CP e MP nos focos de calcificação e na fibrose ao redor do que nas regiões valvulares mais preservadas. Em conclusão, o fato de haver maior quantidade de CP e MP nos focos de calcificação da EVA favorece a hipótese de que a estenose aórtica não é um processo degenerativo inevitável devido a idade, mas sim uma resposta inflamatória à presença dessas bactérias, em uma morfologia semelhante à detectada na injúria aterosclerótica.

This paper reports what is apparently the first observation of Mycoplasma pneumoniae in association with Chlamydia pneumoniae in thrombosed ruptured atheromas. We performed electron microscopy and in situ hybridization in specimens from three patients who died of acute myocardial infarction. These patients had typical symptoms of acute ischemic syndrome. Mycoplasmas were present mainly in the lipid core of the ruptured thrombosed plaque. Vulnerable atheromas are rich in cholesterol and may favor the growth of mycoplasmas, the only microorganisms that require cholesterol for survival. We suggest that the association of Mycoplasma pneumoniae and Chlamydia pneumoniae may increase the virulence of these microorganisms, favoring proliferation, plaque inflammation and possibly plaque rupture.

The immunohistochemical expression of adhesion molecules and class I HLA in chronic chagasic cardiomyopathy were compared with heart allograft rejection and dilated cardiomyopathy, to obtain new knowledge on the occurrence of autoimmunity and inflammation in the pathogenesis of chronic chagasic cardiomyopathy. Semiquantitative immunohistochemistry was performed for CD8+ T cells, ICAM-1, VCAM-1, LFA-1, and class I HLA in frozen sections of myocardial biopsies from patients presenting chronic chagasic cardiomyopathy (group I, n = 12), heart allograft rejection (group II, n = 9) or dilated cardiomyopathy (group III, n = 9). A high mean number of CD8+ T cells/mm 2 was present in group I (18.26) and group II (28.60), but not in group III (0.83). The frequency of high expression for ICAM-1 and VCAM-1 on the endothelial and interstitial cells, and for class I HLA on the cardiomyocytes was greater in group I (100%, 33.3%, and 83.3%, respectively) and group II (100%, 66.7%, and 77.8%, respectively), compared to group III (66.7%, 0%, and 0%, respectively). ICAM-1 and VCAM-1 probably participate in the development of the lymphocytic inflammatory infiltrate present in chronic chagasic cardiomyopathy, as seen in heart allograft rejection. The overexpression of adhesion molecules and the induction of class I HLA on the cardiomyocytes are probably related to the high cytokine levels at the inflammatory sites in chronic chagasic cardiomyopathy. Although the induction of class I HLA on the cardiomyocytes is consistent with an autoimmune reaction, it should not be considered as irrefutable evidence for autoimmunity in chronic chagasic cardiomyopathy. The differential expression of adhesion molecules and class I HLA in dilated cardiomyopathy compared to chronic chagasic cardiomyopathy suggests differences in the pathogenesis of these cardiomyopathies.

Accelerated graft coronary atherosclerosis is the main obstacle to long-term survival in patients who have had a heart transplant. A possible involvement of the human cytomegalovirus (HCMV) in this type of coronary atherosclerosis has been postulated by many authors but has not been definitively demonstrated. In an attempt to clarify the role of HCMV infection in the pathogenesis of this complication, we looked for in situ antigens or DNA of HCMV in 30 coronary artery segments obtained at necropsy from patients who had undergone orthotopic cardiac transplantation at the São Paulo Heart Institute. We tried to correlate these HCMV markers with the presence of inflammation and/or atherosclerosis in histologic sections. The patients were grouped as follows: GI, less than 170 days of graft survival and absent/mild atherosclerosis; GII, more than 170 days of graft survival and absent/mild atherosclerosis; GIII, more than 170 days of graft survival and severe/moderate atherosclerosis (170 days was the shortest graft survival time associated with atherosclerosis). The search for HCMV genome and antigens in the coronary artery sections was performed using immunohistochemistry, in situ hybridization, and polymerase chain reaction in situ techniques. Immunohistochemistry and in situ hybridization revealed no evidence of HCMV in all 30 cases. Polymerase chain reaction in situ revealed scarce HCMV-positive lymphocytes in two cases (one each from GI and GIII) located in the adventitial layer. These findings preclude a direct role for the HCMV in the pathogenesis of accelerated graft coronary atherosclerosis. However, the possibility of an indirect effect of the virus, such as an immune-mediated inflammatory response by the host that increases the expression of histocompatibility antigens, leading to tissue injury, cannot be excluded.

OBJECTIVE—To analyse the morphological aspects of the extracellular matrix and microcirculation to clarify whether chronic Chagas' cardiopathy (CCC) is an accurate model to study the pathogenesis of idiopathic dilated cardiomyopathy (IDCM). DESIGN—Thick histological myocardial sections were prepared to analyse collagen, and microcirculation was examined during confocal laser and light microscopy. SETTING—The specimens were prepared at the pathology service of the Heart Institute of São Paulo, Brazil. PATIENTS—Nine control hearts, eight IDCM hearts, and 10 CCC hearts were studied after necropsy. MAIN OUTCOME MEASURES—The number of collagen struts per 100× field, the area of fibrosis (%), and the diameters of arterioles and capillaries were measured in each heart to establish outcome. RESULTS—A smaller number (mean (SD)) of collagen struts was seen in the hearts in the IDCM group (9.1 (4.1)) than in the control (22.4 (3.2)) (p 0.05) groups. Fibrosis was greater in the CCC hearts (13.8 (10.5)%) than in the IDCM hearts (5.9 (6.6)%) (p > 0.05). Major increases in arteriole (65.4 (9.9) µm) and capillary (9.9 (1.7) µm) diameters were seen in the CCC hearts but not in the IDCM hearts (arteriole diameter 40.3 (7.9) µm; capillary diameter 7.9 (1.3) µm). CONCLUSIONS—Hearts demonstrating CCC and IDCM present different extracellular and microvessel alterations. This suggests that distinct pathogenic mechanisms are responsible for each condition and that CCC is not an effective model to study IDCM. Keywords: microcirculation; Chagas' disease; dilated cardiomyopathy; extracellular matrix

Confocal fluorescence microscopy combined with differential interference contrast imaging of tissues from chagasic patients enabled the unequivocal identification of the parasite Trypanosoma cruzi. Using different monoclonal antibodies that indicate the parasite form and replication stage in conjunction with DNA labelling, specimens derived from distinct clinical forms of the disease were examined. Intracellular amastigote forms of the parasite were clearly detected in heart, brain, skin, lung, and kidney. Dividing amastigotes as well as trypomastigote forms were recognized in samples obtained from patients undergoing either acute-phase or some form of reactivation caused by immunosuppression.

The pathogenesis of chronic chagasic cardiopathy is still a debated matter. In this review, the main theories raised about it since the first description of the disease in 1909 by Carlos Chagas, are considered. The scarcity of T.cruzi parasites into the myocardium and the apparent lack of correlation between their presence and the occurrence of myocardial inflammatory infiltrate, have originated many theories indicating that chronic Chagas' cardiopathy is an autoimmune disease. Recently however, papers using immunohistochemical technique or PCR have demonstrated a strong association between moderate or severe myocarditis and presence of T.cruzi Ags, indicating a direct participation of the parasite in the genesis of chronic chagasic myocarditis. Different patterns of cytokine production seem to have important role in the outcome of the disease. Participation of the microcirculatory alterations and fibrosis as well as the relationship with the parasite are also emphasized. Finally, the author suggests that the indeterminate form of the disease occurs when the host immunological response against the parasite is more efficient while the chronic cardiopathy occurs in patients with hyperergic and inefficient immune responseA patogênese da cardiopatia crônica chagásica ainda é assunto controverso. Na presente revisão as principais teorias patogenéticas propostas, desde a descrição da doença por Carlos Chagas em 1909, são abordadas. A escassez de parasitas do T.cruzi no miocárdio e a aparente falta de correlação entre sua presença e a ocorrência de infiltrado inflamatório no miocárdio originaram várias teorias de autoimunidade na patogênese da cardiopatia crônica chagásica. Entretanto, trabalhos recentes têm demonstratado a presença de Ags do T.cruzi em associação com infiltrado inflamatório chagásico através de técnicas de imunoperoxidase e de PCR, sugerindo fortemente uma participação direta do parasita na gênese dessa miocardite. Diferentes padrões de produção de citocinas parecem desempenhar importante papel na evolução da doença. Ressalta-se também a possível participação do parasita em lesões da microcirculação e fibrose. Finalmente, o autor sugere que a forma indeterminada ocorre em pacientes cuja resposta imunológica contra o T.cruzi é mais efficente, enquanto que pacientes com cardiopatia crônica são aqueles com resposta contra o parasita ineficiente e hiperérgica

The heart is the most commonly affected organ in chronic Chagas' disease, and lymphocytic myocarditis is often observed. However, the pathogenesis of chronic Chagas' heart disease is controversial. The purpose of this study was to determine whether in vivo T. cruzi antigens could be detected in hearts from patients with chronic Chagas' disease and to investigate whether a correlation between these antigens and the intensity of myocardial inflammation exists. We studied 16 patients with chronic Chagas' heart disease. Ten patients had severely impaired left ventricular function and refractory heart failure, and six had episodes of sustained ventricular tachycardia without severe left ventricular dysfunction. Eight patients underwent magnetic resonance imaging with gadolinium enhancement to guide endomyocardial and surgical biopsies to sites with more intense inflammatory processes. Myocardial specimens were studied with immunohistochemical techniques by using rabbit anti-T. cruzi immune serum to detect the presence of T. cruzi antigen. All patients had evidence of some myocarditis in at least one myocardial fragment. T. cruzi antigen was detected in 11 (69%) patients. T. cruzi antigens were detected in 10 (71%) of 14 regions with histopathologic evidence of moderate or severe myocarditis. In contrast, T. cruzi antigens were detected in 3 of 18 regions with only mild or absent myocarditis. There was a statistically significant correlation between the presence of T. cruzi antigens and moderate or severe myocarditis (chi-square = 5.169, p = 0.023). The results of this in vivo study demonstrate that T. cruzi antigens are frequently detected in chronic Chagas' heart disease. In addition, there is an association between the intensity of the inflammatory process and the presence of T. cruzi antigens. The presence of the T. cruzi antigen and its correlation with the severity of myocardial inflammatory process provide strong supportive evidence for the role of T. cruzi even in the chronic forms of Chagas' heart disease.

Although dynamic cardiomyoplasty may promote clinical amelioration and mild improvement in left ventricular function in selected patients, whether cardiac reverse remodeling occurs after the procedure is not clear. We did not find histologic differences among right ventricular endomyocardial biopsy specimens taken before and after the surgery at 3 time periods. This result suggests that the procedure has no effect on the microscopic structure of the right ventricular myocardium. However, because reverse remodeling does not necessarily occur concomitantly in both ventricles, our conclusion cannot be extrapolated to the left ventricular chamber.

ObjectiveTo analyze biomechanical, histologic, and histochemical properties of anterior fragments of abdominal aortic aneurysms (AAA) and to correlate them with the maximum transverse diameter (MTD) and symptoms associated to the aneurysms.MethodsFragments of the anterior aneurysm wall were obtained from 90 patients submitted to open repair of AAA of degenerative etiology from 2004 to 2009 in the Clinics Hospital of São Paulo University Medical School. Two specimens were produced from the fragments: one for histologic analysis for quantification of collagen fibers, elastic fibers, smooth muscle cells, and degree of inflammatory activity and the other for uniaxial tensile test to assess biomechanical failure properties of the material, such as strength, tension, and stress. Cases were classified according to symptoms and to the AAA MTD.ResultsFragments from AAA with MTD < 5.5 cm showed higher values for biomechanical failure properties than those of AAA with MTD < 5.5 cm (strength, 5.32 ± 2.07 × 4.1 ± 2.41 N; tension, 13.83 ± 5.58 × 10.82 ± 6.48 N/cm; stress, 103.02 × 77.03 N/cm2; P < .05). No differences were observed between the groups in relation to failure strain (0.41 ± 0.12 × 0.37 ± 0.14; P = .260) and thickness of the fragments (1.58 ± 0.41 × 1.53 ± 0.42 mm; P = .662). The average values of fiber compositions of all the fragments were as follows: collagen fibers, 44.34 ± 0.48% and 61.85 ± 10.14% (Masson trichrome staining and Picrosirius red staining, respectively); smooth muscle cells, 3.46 ± 2.23% (immunohistochemistry/alpha-actin); and elastic fibers, less than 1% (traces) (Verhoeff-van Gieson staining). No differences in fiber percentages (collagen, elastic, and smooth muscle) were observed in fragments from AAA with MTD

Among 68 children with severe dilated cardiomyopathy, 43 (aged 10 months to 15 years) presented with active myocarditis, diagnosed by endomyocardial biopsy. They were divided into four treatment groups: I, controls: 9 patients submitted to conventional treatment (digitalis, diuretics, and vasodilators) for 8.1 +/- 0.7 (SD) months; II, prednisone: 12 patients received conventional therapy plus prednisone; III, azathioprine: 16 patients submitted to conventional therapy plus prednisone and azathioprine; IV, cyclosporine: 13 patients treated with conventional therapy plus prednisone and cyclosporine. Immunosuppressive therapy was maintained for a mean of 8.4 +/- 1.2 months. They were submitted to noninvasive (electrocardiogram, chest radiograph, Doppler echocardiogram, and radioisotopic scintigraphy) and invasive (hemodynamic) studies. In the control group only 2 of 9 patients showed clinical and hemodynamic improvement and 1 of 4, histologic regression of the myocarditis. Among patients submitted to conventional therapy plus prednisone, 3 of 12 presented clinical and hemodynamic improvement; 2 of 5 also showed histologic regression of inflammatory process. By contrast, patients treated with azathioprine or cyclosporine associated with prednisone had significantly better results: 13 of 16 and 10 of 13 patients, respectively, had clinical and hemodynamic improvement; all 6 patients in the azathioprine group and all 4 patients in the cyclosporine group had histologic regression of the myocarditis. Two patients in the prednisone group, one in the azathioprine group, and one in the cyclosporine group died during treatment, in cardiogenic shock. In our experience immunosuppressive therapy with azathioprine or cyclosporine associated with prednisone improves the prognosis of children with active myocarditis and severe ventricular dysfunction.

The role of autoimmunity in the pathogenesis and progression of heart lesions in the chronic phase of Chagas' disease is controversial. In the absence of parasites in situ, the T cell infiltrate seen in heart lesions may be the primary determinant of tissue damage ultimately leading to heart failure and death. We used the polymerase chain reaction to amplify each known T cell receptor (TCR) V alpha and V beta subfamily-specific sequence in transcripts derived from heart samples obtained from Chagas' cardiomyopathy patients. The average number of TCR V alpha subfamilies (7.1 per tissue sample) was significantly lower than that for TCR V beta subfamilies (15.1 per sample). The average percentage of tissue samples positive per TCR V alpha and V beta subfamily was respectively 39.6% vs. 73.5%. These data suggest that, in Chagas' heart lesions, the detectable TCR V alpha repertoire is significantly narrower than TCR V beta repertoire. On the other hand, in normal heart tissue, diversity of V alpha and V beta TCR is similar among the scarce circulating T cell population. Such evidence of restricted TCR V region repertoire has been described in experimental and human autoimmune diseases. Our results are consistent with the possibility that T cells responsible for heart damage in chronic Chagas' cardiomyopathy may be recognizing a few heart-specific antigenic targets.

Outer mitochondrial membrane (OMM) rupture was first noted in isolated mitochondria in which the inner mitochondrial membrane (IMM) had lost its selective permeability. This phenomenon referred to as mitochondrial permeability transition (MPT) refers to a permeabilized inner membrane that originates a large swelling in the mitochondrial matrix, which distends the outer membrane until it ruptures. Here, we have expanded previous electron microscopic observations that in apoptotic cells, OMM rupture is not caused by a membrane stretching promoted by a markedly swollen matrix. It is shown that the widths of the ruptured regions of the OMM vary from 6 to 250 nm. Independent of the perforation size, herniation of the mitochondrial matrix appeared to have resulted in pushing the IMM through the perforation. A large, long focal herniation of the mitochondrial matrix, covered with the IMM, was associated with a rupture of the OMM that was as small as 6 nm. Contextually, the collapse of the selective permeability of the IMM may precede or follow the release of the mitochondrial proteins of the intermembrane space into the cytoplasm. When the MPT is a late event, exit of the intermembrane space proteins to the cytoplasm is unimpeded and occurs through channels that transverse the outer membrane, because so far, the inner membrane is impermeable. No channel within the outer membrane can expose to the cytoplasm a permeable inner membrane, because it would serve as a conduit for local herniation of the mitochondrial matrix. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.

ObjectivesWe sought to determine whether the quantitative assessment of myocardial fibrosis (MF), either by histopathology or by contrast-enhanced magnetic resonance imaging (ce-MRI), could help predict long-term survival after aortic valve replacement.BackgroundSevere aortic valve disease is characterized by progressive accumulation of interstitial MF.MethodsFifty-four patients scheduled to undergo aortic valve replacement were examined by ce-MRI. Delayed-enhanced images were used for the quantitative assessment of MF. In addition, interstitial MF was quantified by histological analysis of myocardial samples obtained during open-heart surgery and stained with picrosirius red. The ce-MRI study was repeated 27 ± 22 months after surgery to assess left ventricular functional improvement, and all patients were followed for 52 ± 17 months to evaluate long-term survival.ResultsThere was a good correlation between the amount of MF measured by histopathology and by ce-MRI (r = 0.69, p < 0.001). In addition, the amount of MF demonstrated a significant inverse correlation with the degree of left ventricular functional improvement after surgery (r = −0.42, p = 0.04 for histopathology; r = −0.47, p = 0.02 for ce-MRI). Kaplan-Meier analyses revealed that higher degrees of MF accumulation were associated with worse long-term survival (chi-square = 6.32, p = 0.01 for histopathology; chi-square = 5.85, p = 0.02 for ce-MRI). On multivariate Cox regression analyses, patient age and the amount of MF were found to be independent predictors of all-cause mortality.ConclusionsThe amount of MF, either by histopathology or by ce-MRI, is associated with the degree of left ventricular functional improvement and all-cause mortality late after aortic valve replacement in patients with severe aortic valve disease.

Study objective — The aim was to investigate alterations in sulphated glycosaminoglycans in aortic dissection. Design — Aortic fragments were taken from 10 patients within the first 3 d after onset of symptoms of aortic dissection and from nine age matched patients with no aortic disease. Sulphated glycosaminoglycans were analysed and quantified by agarose gel electrophoresis and densitometry after degradation with specific enzymes. Measurements and main results — The amount of chondroitin sulphate was similar (7.14 ν 7.60 mg·g−1 of dry tissue, n = 10, p>0.5) in patients with dissection and in the control group. Total sulphated glycosaminoglycan content was decreased (11.51 ν 14.26 mg·g−1 of dry tissue, n = 10, p

This study aims to analyze the embolic activity in patients with calcified aortic stenosis who underwent aortic valve replacement using intra-aortic filtration with an EMBOL-X System device (Edwards Lifesciences Inc., Mountain View, CA, USA).From January 2007 to July 2007, 13 consecutive patients with calcified aortic stenosis, who underwent isolated aortic valve replacement using intra-aortic filtration by an EMBOL-X System for 5 minutes after aortic clamp release, were evaluated. Mean patient age was 63.7 years (range 34 to 79 years) and 61.5% were female. The mean bypass time was 60.2 +/- 7.5 minutes (range 45 to 72 minutes) and the mean cross-clamp time was 50 +/- 7.5 minutes (range 35 to 63 minutes). Following removal, each filter was fixed in formalin and analyzed macroscopically with the captured fragments being counted. Histological examinations of the captured material were performed.There were no strokes or gross neurological events. There were no cases of postoperative renal failure. No deaths were reported during hospitalization. Particulate emboli were found in five (38.5%) of the filters. On histological analysis of the particulate emboli captured, two (40%) contained fibrin, two (40%) presented conjunctive tissue, one (20%) contained red blood cells and in one it was not possible to determine the nature of the particulates captured.The EMBOL-X System device was effective in particulate emboli capture in aortic valve replacement surgery of patients with calcified aortic stenosis.

This work is a detailed study of the relevance of three sets of criteria to define myocarditis: Dallas meeting criterion, Edwards criterion and Dallas meeting criterion modified by the authors. Two groups were evaluated: normal autopsied hearts and endomyocardial biopsy from chronic chagasic patients at high risk of having myocarditis. Furthermore, endomyocardial biopsies from patients with dilated cardiomyopathy (DCM) were also evaluated . Applying the Edwards criterion, incidences of myocarditis in normal and chagasic hearts were 0% and 67% while with Dallas meeting criterion they were 0% and 42% and using our criterion the incidences were 0% and 92% respectively. In endomyocardial biopsies from DCM patients, the incidence of myocarditis was 7% with Edwards criterion, 22% with Dallas meeting and 33% with the authors own criterion. The authors concluded that their criterion, which defines myocarditis as the presence of inflammatory mononuclear cells enclosing more than 2 lymphocytes/400X aggregated to the cardiac fiber sarcolemma, is the most appropriate criterion of the three. Myocarditis was found in 33% of the 27 endomyocardial biopsy specimens from patients with DCM.

Currently, many cases of heart amyloidosis still fail to be diagnosed.To disclose factors related to the difficulty in attaining the diagnosis of cardiac amyloidosis.We compared the clinical, electrocardiographic and echocardiographic data of 17 patients in whom amyloidosis was diagnosed only at the necropsy (group I) with data from 9 patients in whom the disease was diagnosed in life (group II). The quantitative variables were compared by t-test and qualitative ones by Fisher's exact test. Significance was set at por = 0.05.The two groups showed differences regarding age (group I: 75.29 +/- 11.61, group II: 58.67 +/- 11.07 years), association with other cardiac disease (group I: 52.94%, group II: 0%), low voltage at the ECG (group I: 17.65%, group II: 66.67%), and diastolic dysfunction at the echocardiogram (group I: 7.69%, group II: 62.50%). Some degree of left ventricular thickening was found in 75% of necropsy cases and 100% of controls (p=0.23), but wall thickness was lower in group I (free left ventricular wall: 1.20 +/- 0.28 cm versus 1.53 +/- 0.18 cm in group II, p=0.01). Systolic dysfunction was present in 57.89% of the cases, without significant difference between the groups.Amyloidosis is diagnosed when the clinical, ECG, and echocardiogram patterns are "typical", but most of the cases fail to be diagnosed, especially in elderly people, due to the association with other cardiac diseases, lack of diastolic dysfunction at the echocardiogram and only a slightly thickened ventricular wall.

PURPOSE: Vulnerable plaques are characterized by a myxoid matrix, necrotic lipidic core, reactive oxygen species, and high levels of microorganisms. Aerobic microbes such as Chlamydophila pneumoniae and Mycoplasma pneumoniae usually do not survive in oxidative stress media. Archaea are anaerobic microbes with powerful anti-oxidative enzymes that allow detoxification of free radicals whose presence might favor the survival of aerobic microorganisms. We searched for archaeal organisms in vulnerable plaques, and possible associations with myxoid matrix, chlamydia, and mycoplasma bodies. METHODS: Twenty-nine tissue samples from 13 coronary artherectomies from large excentric ostial or bifurcational lesions were studied using optical and electron microscopy. Infectious agents compatible with archaea, chlamydia, and mycoplasma were semiquantified using electron micrographs and correlated with the amounts of fibromuscular tissue, myxoid matrix, and foam cells, as determined from semi-thin sections. Six of the cases were also submitted to polymerase chain reaction with archaeal primers. RESULTS: All 13 specimens showed archaeal-compatible structures and chlamydial and mycoplasmal bodies in at least 1 sample. There was a positive correlation between extent of the of myxoid matrix and archaeal bodies (r = 0.44, P = 0.02); between archaeal and mycoplasmal bodies (r = 0.41, P = 0.03), and between chlamydial bodies and foam cells (r = 0.42; P = 0.03). The PCR test was positive for archaeal DNA in 4 of the 6 fragments. DISCUSSION: DNA and forms suggestive of archaea are present in vulnerable plaques and may have a fundamental role in the proliferation of mycoplasma and chlamydia. This seems to be the first description of apparently pathogenic archaea in human internal organ lesions. PROPOSTA: Placas vulneráveis são caracterizadas por matriz mixomatosa, centro lipídico necrótico, espécies reativas de oxigênio e alto níveis de microorganismos. Micróbios aeróbicos como Chlamydophila pneumoniae e Mycoplasma pneumoniae usualmente não sobrevivem em meio de estresse oxidativo. Arquéias são microorganismos anaeróbicos com poderosas enzimas anti-oxidantes que permitem detoxificação de radicais livres e a presença delas poderia favorecer a sobrevivência de micróbios aeróbicos. Pesquisamos por elementos de arquéia em placas vulneráveis e sua possível associação com degeneração mixomatosa da matriz e aumento do número de clamídias e micoplasmas. MÉTODOS: Vinte e nove amostras de 13 produtos de aterotomia de lesões grandes e excêntricas de óstio ou bifurcação de coronárias foram estudadas pela microscopia óptica e eletrônica. Agentes compatíveis com arquéia, clamídia e micoplasma foram semiquantificados pela microscopia eletrônica e correlacionados com quantidade de tecido fibromuscular, matriz mixomatosa e células xantomatosas. Seis casos foram também submetidos à reação em cadeia da polimerase com oligonucleotídeos de arquéia. RESULTADOS: Os 13 casos foram positivos para estruturas sugestivas de arquéia, micoplasma ou clamídia, em pelo menos uma amostra. Houve correlação positiva entre intensidade de matriz mixomatosa versus arquéia (r=0.44, p=0.02); arquéia versus micoplasma (r=0.41, p=0.03) e clamídia versus células xantomatosas r=0,42; 0.03). PCR foi positiva para DNA de arqueia em 4 dos 6 fragmentos. DISCUSSÃO: DNA e formas compatíveis com arquéia estão presentes em placas vulneráveis e podem ter papel fundamental na proliferação de micoplasma e clamídia. Este parece ser o primeiro relato de arquéia aparentemente patogênica em lesões de órgãos internos humanos.

Morphometric data obtained from the analysis of endomyocardial biopsy might be useful to evaluate prognosis of patients with dilated cardiomyopathy. We measured the myocyte diameter, its coefficient of variation and the fractional area of collagen in right ventricular endomyocardial biopsies of 35 outpatients with idiopathic dilated cardiomyopathy. None of the evaluated histological parameter was associated with the survival time of the patients (range: 2 to 5588; median: 706 days). Right ventricular endomyocardial biopsy should not be indicated to predict evolution or fatal outcome in patients with idiopathic dilated cardiomyopathy.

Advanced complicated atherosclerotic lesions have been related to many factors, including inflammation, infectious agents, and growth factors. Mycoplasma pneumoniae (MP) and Chlamydia pneumoniae (CP), inflammation, and growth factors have been associated with severe atherosclerotic lesions in necropsy material in recent work at our lab. The present study intends to clarify the pathogenesis of atherosclerosis, analyzing which of these elements (macrophages, MP, CP, lymphocytes, and growth factors) are associated with initial development of atherosclerotic lesions, discriminating elements related to stabilization of the plaque versus those related to subendothelial active accumulation of macrophages in living patients. Surgical ascending aorta fragments presenting mild atherosclerotic lesions from 30 coronary atherosclerotic patients were immunohistochemically quantified regarding CP, MP, T cells (CD4, CD8), B cells (CD20), macrophages (CD68), and growth factors [platelet-derived growth factor A (PDGF-A), PDGF-B, transforming growth factor-beta (TGF-beta), granulocyte-macrophage colony-stimulating factor (GM-CSF)]. Cases were grouped according to the presence or not of active accumulation of macrophages at the subendothelium that indicates atheroma in development: group I (GI) fragments with4 CD68+ cells/x400 field, in normal distribution (mean 1.8 +/- 1) representing stable atherosclerotic mild lesion, and GII fragments presentingor=4 CD68+ cells/x400 field, in a non-normal distribution, mean (8.9 +/- 4.8, atheromas in progress), which was followed by increased number of lymphocytes. The median number in GI was significantly lower than that in GII: CD4 T (2.5 vs. 7.7), CD8 T (1.0 vs. 5.5), and CD20 B (1.5 vs. 5.5) cells/x400 field, p0.001. Percentage area positive for CP antigens was significantly lower in GI than in GII: 1.0 vs. 9.2, p0.001. There was a higher percentage area occupied by MP than CP in both GI and GII (7.8 vs. 13.8). There was no difference regarding mean number of growth factor-positive cells/x400 field: PDGF-A, 1.4 vs. 3.9; PDGF-B, 3.4 vs. 5.7; TGF-beta, 0.9 vs. 2.2; and GM-CSF, 2.0 vs. 2.2. Considering all cases, a positive correlation was seen between inflammatory cells and CP+ cells (r0.5 and p0.01). Growth factors did not correlate with inflammatory cells, CP, or MP and were usually seen in smooth muscle cell and fibrotic areas. Study of initial atherosclerotic lesions showed that MP is present in both kinds of lesion: stable and active subendothelial accumulation of macrophages. Stabilization was related to proportional increase of both infectious agents, which were also related to increased amount of PDGF-A and PDGF-B. Active macrophage accumulation lesions were related to higher elevation in CP concentration at subendothelial regions, in association with B cells, but not of MP and growth factors. MP and CP, inflammation, and growth factors, which were already described in severe atherosclerotic lesions in necropsy material, are also present in mild lesions in living patients, strongly favoring a pathogenetic role for these bacteria in the pathogenesis of atherosclerosis. Predominance of CP in relation to MP may favor progression of the plaque, which is associated with increased B-cell proliferation. PDGF-A and PDGF-B are associated with plaque stability, at least in arterial segments not prone for development of complicated lesions.

PURPOSE: To investigate the relationship between the vascular diameter and the extent and histologic characteristics of atherosclerosis in the thoracic and abdominal aortas of patients who died of atherosclerotic disease. METHOD: We measured the vascular diameter and evaluated the percentage atrophy of the medial layer of the thoracic and abdominal aortas of 19 patients who died due to atherosclerotic disease. The extent of plaques, calcification, ulceration, thrombosis, and the amount of fat in the plaques were evaluated semiquantitatively. RESULTS: Atherosclerosis was more severe in the abdominal than the thoracic aorta as indicated by the higher sum of the macroscopic scores (P = .02) and the higher percentage atrophy of the medial layer (P < .001). The diameter of the thoracic, but not of the abdominal aorta, correlated with age (r = 0.56; P = .01), plaque score (r = 0.59; P = .008), calcification score (r = 0.749; P < .001), and fat score (r = 0.48; P = .04). Multiple linear regression showed that age (P = .06) and calcification score (P = .001) were the parameters with the strongest association to thoracic aorta diameter. CONCLUSION: There are some differences regarding atherosclerosis in the thoracic compared to the abdominal aorta. Progressive thoracic aorta atherosclerosis is associated with fat deposition in the plaques, inducing arterial dilation. In the abdominal aorta, atherosclerosis can either have a similar evolution or be associated with less fat deposition in the arterial wall, which would result in more rigidity, hindering compensatory arterial enlargement. OBJETIVO: Estabelecer relações entre o diâmetro vascular e a intensidade e características histológicas da aterosclerose, nos segmentos torácico e abdominal da aorta. MÉTODO: Foi medido o diâmetro vascular e avaliada a porcentagem de atrofia da camada média da aorta torácica e abdominal de 19 pacientes que faleceram devido a doença aterosclerótica. A presença de placas, calcificação, ulceração, trombose e a quantidade de gordura das placas foi avaliada, semiquantitativamente, nas mesmas regiões. RESULTADOS: A aterosclerose foi mais intensa na aorta abdominal que na torácica, conforme demonstrado pela maior soma dos escores macroscópicos (p = 0,02) e pela maior porcentagem de atrofia da camada média (p < 0,001). O diâmetro da aorta torácica, porém não o da abdominal apresentou correlação positiva com a idade (r = 0,56; p = 0,01), escore de placa (r = 0,59; p = 0,008), escore de calcificação (r = 0,749; p < 0,001) e escore de gordura (r = 0,48; p = 0,04). O modelo de regressão linear múltipla evidenciou que as variáveis mais associadas ao diâmetro da aorta torácica foram a idade (p = 0,06) e o escore de calcificação (p = 0,001). CONCLUSÃO: A aterosclerose apresenta algumas características distintas nos segmentos torácico e abdominal da aorta. A progressão da aterosclerose na aorta torácica associa-se à deposição de gordura nas placas, ocorrendo dilatação arterial. Na aorta abdominal a aterosclerose pode apresentar evolução semelhante ou estar relacionada à menor deposição de gordura na parede arterial, que se tornaria mais rígida, impedindo a dilatação compensatória.

We investigated whether Chlamydia pneumoniae (CP) and Mycoplasma pneumoniae (MP) are present in aortic valve stenosis (AS).Immunohistochemistry was utilized to identify CP antigens, in situ hybridization to identify MP DNA, and electron microscopy was used to evaluate the following three groups: Normal - 11 normal autopsy valves; Atherosclerosis - 10 autopsy valves from patients with systemic atherosclerosis and no AS; and AS - 14 surgical specimens of AS analyzed in 3 sub-regions: AS-Preserved - peripheral, preserved regions; AS-Fibrosis - peri-calcified fibrotic tissue; and AS-Calcification - calcified nodules.The positive area fraction of CP antigen median values were 0.09, 0.30, 0.18, 1.33, and 3.3 in groups Normal, Atherosclerosis, AS-Preserved, AS-Fibrosis, and AS-Calcification, respectively. CP density was significantly greater in Atherosclerosis and AS-Calcification than in Normal (P0.05). Within the AS group, the amount of CP was greater in the Calcification and Fibrosis regions (P0.05). MP-DNA positive area fraction (median values) were 0.12, 0.44, 0.07, 0.36, and 1.52 in groups Normal, Atherosclerosis, AS-Preserved, AS-Fibrosis, and AS-Calcification, respectively. The amount of MP-DNA was greater in AS-Calcification than in Normal (P0.05). Within the AS group, MP-DNA was in larger quantity in the Calcification and Fibrosis regions (P0.05).AS Calcified nodes present higher concentration of CP and MP suggesting that these bacteria may be associated with the development of calcification and inflammation. This adds novel similarities between AS and the atherosclerosis process, which may have infection mechanisms involved.

Polymerase chain reaction (PCR) has been used to detect microbiological agent recurrence after heart transplantation of viral-induced cardiomyopathies. We report a case of reactivation of Chagas' disease after heart transplantation in which parasites could be detected in the endomyocardial biopsy using hematoxylin-eosin-stained sections, immunohistochemistry, and PCR for Trypanosoma cruzi DNA. Interestingly, PCR results remained positive in the endomyocardial biopsy 53 days after the beginning of successful treatment, pointing to the possibility of chronic persistence of parasites in the myocardium after the reactivation of Chagas' disease.

A lower incidence of acute myocardial infarction was reported in patients with chronic liver disease.To analyze the impact of chronic liver disease on characteristics associated with vulnerability of human coronary artery atherosclerotic plaques.One hundred fourteen hearts were collected from 3 groups of individuals: A--38 chronic liver disease patients who died while on the waiting list for liver transplantation; B--38 individuals who died of natural causes; and C--38 individuals who died of accidental causes. The most obstructed portion of the initial 2-cm segment of coronary arteries was histologically evaluated regarding to plaque area, luminal area, inflammation, percentage of fat, and total vessel area.The mean age (years) and male frequency in groups A, B and C were, respectively, 52+/-9 and 79%; 52+/-11 and 71%; and 54+/-18 and 89%. The mean area of the plaque and the incidence of severe plaque inflammation in group A were significantly lower (4.2+/-3.2; 13.2%) than those in the other two groups (6.6+/-4.3; 84.2%, and 6.3+/-4.4; 52.6%) p0.01. The cross-sectional vessel measures were not statistically different regarding to vessel area (10.5+/-4.6; 12.1+/-4.6; 13.0+/-4.4) p=0.08, luminal obstruction (45%+/-15%; 60%+/-20%; 53%+/-20%) p=0.07, and fat area in the plaque (16%+/-17%; 30%+/-24%; 18%+/-18) p=0.37. In conclusion, compared with the general population, chronic liver disease patients have coronary arteries with smaller intimal plaque and less vessel inflammation. These findings favor the concept that hepatic disease patients are less prone to develop complicated coronary atherosclerosis.

In this review we report recent findings of our lab showing that Mycoplasma pneumoniae and Chlamydia pneumoniae are present in higher amount, associated with adventitial inflammation and positive vessel remodeling, in thrombosed coronary artery segments (CAS) of patients who died due to acute myocardial infarction. CD8T cell was the predominant lymphocytes in the plaque and CD24(B) cell in the adventitia. The mean numbers of lymphocytes were significantly higher in adventitia than in the plaque. Vulnerable plaques were usually associated with focal positive vessel remodeling and large lipidic atheromas. Mycoplasma is the only bacterium that needs cholesterol for proliferation. We hypothesized that the association of Mycoplasma pneumoniae and Chlamydia pneumoniae increases virulence of both bacteria, inducing inflammation and rupture of the plaque. The search of CMV and Helicobacter pylori resulted negative.