Microbiota-derived peptide mimics drive lethal inflammatory cardiomyopathy.

Myocarditis can develop into inflammatory cardiomyopathy through chronic stimulation of myosin heavy chain 6-specific T helper (TH)1 and TH17 cells. However, mechanisms governing the cardiotoxicity programming of heart-specific T cells have remained elusive. Using a mouse model of spontaneous autoimmune myocarditis, we show that progression of myocarditis to lethal heart disease depends on cardiac myosin-specific TH17 cells imprinted in the intestine by a commensal Bacteroides species peptide mimic. Both the successful prevention of lethal disease in mice by antibiotic therapy and the significantly elevated Bacteroides-specific CD4+ T cell and B cell responses observed in human myocarditis patients suggest that mimic peptides from commensal bacteria can promote inflammatory cardiomyopathy in genetically susceptible individuals. The ability to restrain cardiotoxic T cells through manipulation of the microbiome thereby transforms inflammatory cardiomyopathy into a targetable disease.

A 38-Year-Old Man With a 2-Month History of Fever, Cough, Palpitations, and Weight Loss.

CASE PRESENTATION: A 38-year-old man of Indian origin, who migrated to Greece 13 years prior to presentation, was admitted to our hospital with a 2-month history of nonprogressive, intermittent (mostly evening), low-grade (up to 38.5°C) fever, accompanied by night sweats, dry cough, mild dyspnea on exertion (modified Medical Research Council Dyspnea Scale grade 1), anorexia, fatigue, and weight loss of 10 kg. He also experienced continuous palpitations, which were regular, not associated with chest pain or dizziness, and aggravated on exertion. He had not taken any medication for his condition, except for antipyretic agents, nor had he sought medical advice. He was a nonsmoker, had a history of past alcohol dependence, and had been hospitalized twice for acute pancreatitis due to hypertriglyceridemia. He had also been diagnosed with diabetes mellitus, presumably poorly controlled because he mentioned not taking any medication or having regular follow-up.

Bartonella-associated inflammatory cardiomyopathy in a dog.

A 6-year-old, male, mongrel dog was presented for acute onset of dyspnea and cough. At admission, the dog was cachectic and severely depressed. The electrocardiogram showed a sinus rhythm conducted with left bundle truncular branch block and interrupted by frequent multiform ventricular ectopic beats organized in allorhythmias. Thoracic radiographs revealed a marked cardiomegaly with perihilar edema, whereas transthoracic echocardiography revealed a dilated cardiomyopathy with segmental dyskinesis. Furosemide, enalapril, pimobendan, and mexiletine were prescribed, and a Holter was scheduled after resolution of congestive heart failure. Three days later, the dog died suddenly during sleep. Histopathology revealed diffuse myocyte hypertrophy with multifocal hemorrhages, alternating to areas of severe replacement fibrosis and lymphoplasmocytic infiltrates. Immunohystochemistry stains were strongly positive for T-lymphocyte infiltration (CD3) and weakly positive for B-lymphocytes (CD79). Polymerase chain reaction was positive for Bartonella spp. Based on these results, a post-mortem diagnosis of bacterial inflammatory cardiomyopathy was made.

A high frequency of viral agents yet absence of Borrelia burgdorferi is seen within the myocardium of subjects with normal left ventricular systolic function: an electron microscopy study.

A wide range of viral agents is associated with the development of acute myocarditis and its possible chronic sequela, dilated cardiomyopathy (DCM). There is also increasing evidence that Borrelia burgdorferi (Bb) is associated with DCM in endemic regions for Bb infection. This study sought to use electron microscopy to prospectively analyze the presence of viruses and Bb within the myocardium of 40 subjects with preserved left ventricular (LV) ejection fraction and 40 patients with new-onset unexplained DCM during the same time period. Virus particles were found within the myocardium of 23 subjects (58%) of both cohorts studied, yet there was no statistically significant difference in virus family presence between those with DCM versus those with preserved LV systolic function. In contrast, Bb was detected only in those subjects with DCM (0 versus 5 subjects; p ˂ 0.05). Polymerase chain reaction was performed on samples from patients who were positive for Bb according to electron microscopy, and Bb was confirmed in 4 out of 5 individuals. Our results demonstrate that the prevalence of viral particles does not differ between subjects with preserved LV systolic function versus those with DCM and therefore suggests that the mere presence of a viral agent within the myocardium is not sufficient to establish a clear link with the development of DCM. In contrast, the presence of Bb was found only within myocardial samples of patients with DCM; this finding supports the idea of a causal relationship between Bb infection and DCM development.

Absence of Borrelia burgdorferi in the myocardium of subjects with normal left ventricular systolic function: a study using PCR and electron microscopy.

BACKGROUND: Several studies have demonstrated the presence of the Borrelia burgdorferi (Bb) genome in the myocardium of patients with dilated cardiomyopathy (DCM). To further support a causal relationship between the presence of Bb in the heart muscle and the development of DCM, demonstration of the absence of Bb in the myocardium of subjects with normal left ventricular (LV) systolic function is needed. AIM: To determine the prevalence of Bb by polymerase chain reaction (PCR) and electron microscopy (EM) in individuals with normal LV systolic function and no history suggestive of myocarditis. METHODS: We investigated 50 patients (67 ± 9 years, 15 women) with normal LV ejection fraction (EF) ≥ 50% undergoing cardiac surgery. During surgery, four samples from the right atrial appendage were obtained and subsequently examined by PCR and EM for the presence of Bb, and by immunohistochemistry to detect inflammatory cells. Serological testing of antibodies against Bb was also performed. RESULTS: Neither PCR nor EM detected Bb in any of the subjects. Immunohistological examination revealed myocardial inflammation in 2 individuals (4%). Serological analysis by enzyme-linked immunosorbent assay demonstrated IgM antibodies against Bb in 4% and IgG antibodies in 12% of the study cohort; Western blot revealed IgM as well as IgG positivity in 14% of patients. CONCLUSIONS: The absence of Bb in the myocardium of individuals who undergo cardiac surgery and have normal LV systolic function supports the idea of Bb pathogenicity in the development of DCM.

Recent-onset dilated cardiomyopathy associated with Borrelia burgdorferi infection.

BACKGROUND: Several recent small studies have suggested a causal link between Lyme disease and dilated cardiomyopathy (DCM) by demonstrating the presence of the Borrelia burgdorferi (Bb) genome in the myocardium of patients with recent-onset DCM. The aim of this study was to further investigate the effect of targeted antibiotic treatment of Bb-related recent-onset DCM in a larger cohort of patients. PATIENTS AND METHODS: We performed endomyocardial biopsy (EMB) in 110 individuals (53 ± 11 years, 34 women) with recent-onset unexplained DCM, and detected the Bb genome in 22 (20 %) subjects. Bb-positive patients were subsequently treated with intravenous ceftriaxone for 21 days in addition to conventional heart failure medication. RESULTS: At the 1-year follow-up, a significant improvement in left ventricular (LV) ejection fraction (26 ± 6 vs. 44 ± 12 %; p < 0.01) and a decrease in LV end-diastolic (69 ± 7 vs. 63 ± 11 mm; p < 0.01) and end-systolic (61 ± 9 vs. 52 ± 4 mm; p < 0.01) diameters were documented. Moreover, a significant improvement in heart failure symptoms (NYHA class 3.4 ± 0.6 vs. 1.5 ± 0.7; p < 0.01) was also observed. CONCLUSION: Targeted antibiotic treatment of Bb-related recent-onset DCM in addition to conventional heart failure therapy is associated with favorable cardiac remodeling and improvement of heart failure symptoms.

Miocardiopatía dilatada: aspectos genéticos, infecciosos, inflamatorios y del sistema inmune / Dilated cardiomyopathy: genetics, infectious, inflammatory and immune aspects

En la última década se ha producido un incremento sustancial en el conocimiento de las bases genéticas de las cardiomiopatías, en consideración a lo cual las Sociedades Americanas y Europea de Cardiología, han propuesto una nueva clasificación con el fin de incluir tales aspectos, Aunque se carece de datos precisos, aproximadamente el 30% de los pacientes con miocardiopatías referidos para pruebas genéticas presentan una variante genética patogénica. En la herencia de la miocardiopatía dilatada familiar, la modalidad predominante es la autosómica dominante, siendo mucho menos frecuentes las ligadas al cromosoma X, la herencia autosómica recesiva y la mitocondrial. A su vez, pruebas provenientes de ensayos clínicos y experimentales indican que la infección, la inflamación y el sistema inmunológico están de alguna manera interrelacionados en los mecanismos patogénicos implicados en la miocardiopatía dilatada, No hay duda que en un futuro próximo las mejoras en la secuenciación de genes y el mayor conocimiento de la patogenia influirán decididamente en el diagnóstico, evaluación y tratamiento de esta entidad.

In the last time, a substantial increase in the knowledge of the genetic basis of cardiomyopathy has occurred. Therefore in the last decade the American Heart Association, the American College of Cardiology and the European Society of Cardiology have proposed a new revision of the classification of cardiomyopathies in order to include the genetic basis on the etiology, Although precise data are lacking, approximately 30% of patients currently referred for clinical genetic testing will be found to have a pathogenic genetic variant. The predominant mode of inheritance for familial dilated cardiomyopathy is autosomal dominant, with X linked autosomal recessive and mitochondrial inheritance being less frequent. Evidence from experimental and clinical trials indicates that infection, inflammation and the immune system are in some way interrelated on the pathogenic mechanisms involved in the dilated cardiomyopathy, There is no doubt that in the future, improvements in sequencing genes and insight into pathogenesis will influence the diagnosis, evaluation and management of familial dilated cardiomyopathy.

Infectious agents and inflammation in donated hearts and dilated cardiomyopathies related to cardiovascular diseases, Chagas' heart disease, primary and secondary dilated cardiomyopathies.

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.

Detection of Borrelia burgdorferi sensu lato in endomyocardial biopsy specimens in individuals with recent-onset dilated cardiomyopathy.

AIMS: Recent studies in patients with dilated cardiomyopathy (DCM) have detected the genome of Borrelia burgdorferi sensu lato (BBSL) in endomyocardial biopsy (EMB) specimens using a qualitative polymerase chain reaction (PCR), suggesting a causal link between Lyme disease and DCM in areas in which Lyme disease is endemic. We aimed to study this relationship using a comprehensive molecular analysis detecting BBSL in EMB samples. METHODS AND RESULTS: We performed a comprehensive histopathological, immunohistochemical, ultrastructural, and molecular analysis targeting cardiotropic viruses and BBSL in EMB specimens of 41 individuals with recent-onset DCM and 15 controls with end-stage coronary artery disease. Specifically, quantitative PCR and electron microscopy of EMB specimens were employed. In addition, autoantibodies and manifestation of autoimmune diseases were evaluated in both groups. Individuals with recent-onset DCM presented more frequently with myocardial BBSL persistence as compared with the control group (24% vs. 0%, P = 0.035). In contrast, the prevalence of parvovirus B19 and cytomegalovirus was similar in both groups. Sequence analysis of borrelial DNA revealed the following genospecies: Borrelia burgdorferi sensu stricto in three patients (30%), Borrelia afzelii in two patients (20%), and Borrelia garinii in four patients (40%), the results being inconclusive in one case. BBSL-positive DCM patients had a higher prevalence of organ-specific autoimmune diseases in comparison with the remaining DCM patients (50% vs. 16%, P = 0.030). CONCLUSION: Myocardial persistence of BBSL may be involved in the pathophysiology of DCM in individuals living in areas in which Lyme disease is endemic.

Presence of Borrelia burgdorferi in endomyocardial biopsies in patients with new-onset unexplained dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) represents the third most common cause of heart failure and the most frequent cause of heart transplantation. Infectious, mostly viral, and autoimmune mechanisms, together with genetic abnormalities, have been reported as three major causes of DCM. We hypothesized that Lyme disease (LD), caused by spirochete Borrelia burgdorferi (Bb), might be an important cause of new-onset unexplained DCM in patients living in a highly endemic area for LD such as the Czech Republic. We performed endomyocardial biopsy (EMB) in 39 consecutive patients presenting with symptomatic unexplained left ventricular (LV) systolic dysfunction lasting no more than 12 months. In eight subjects (21%), Bb was detected in the EMB sample by polymerase chain reaction or by electron microscopy. None of these patients exhibited any form of atrioventricular block or other extracardiac manifestation of Bb infection. Serological testing identified IgG antibodies against Bb in only two cases and IgM antibodies in none. All affected patients were treated with intravenous ceftriaxone for 3 weeks. At 6 months follow-up, LV morphology and function as well as functional status of these patients significantly improved. In conclusion, Bb infection may represent an important cause of new-onset unexplained DCM in patients living in endemic regions such as the Czech Republic. Because the antibiotic treatment appears to be markedly effective and serological examination does not provide a tool for diagnosing the disease, EMB focused on the detection of Bb should be performed in all patients from endemic areas with new-onset unexplained DCM not responding to conventional therapy.

[Familial predisposition and microbial etiology in dilated cardiomyopathy]. / Familiäre Prädisposition und mikrobielle Atiologie bei dilatativer Kardiomyopathie.

Cardiomyopathies are an important and diverse group of heart muscle diseases in which the heart muscle itself is structurally or functionally abnormal and in which coronary artery disease, hypertension, valvular and congenital heart disease are absent or do not sufficiently explain the observed myocardial abnormality. This often results in severe heart failure accompanied by arrhythmias and/or sudden death. Clinical and morphological diversity of cardiomyopathies can reflect the broad spectrum of distinct underlying molecular causes or genetic heterogeneity. In many cases the disease is inherited and is termed familial dilated cardiomyopathy (FDC), which may account for up to 30% of dilated cardiomyopathies (DCM). FDC is principally caused by genetic mutations in FDC genes that encode for cytoskeletal, nuclear and sarcomeric proteins in the cardiac myocyte. In addition, modifying genes, lifestyle and additional factors were reported to influence onset of disease, disease progression, and prognosis. The individual patient's phenotype may reflect a summation and/or interaction of the underlying mutation(s) with other genetic or environmental factors. During the last years major advances have been made in the understanding of the molecular and genetic basis of this type of disease. Nevertheless, much more progress in the identification of underlying mutations, susceptibility genes and modifier genes is important and indispensable for the development of new etiology-orientated forms of therapy. A pivotal role for autoimmunity in a substantial proportion of patients with DCM is supported by the presence of organ-specific autoantibodies, inflammatory infiltrates and pro-inflammatory cytotoxic cytokines. Furthermore, familial occurrence of DCM goes ahead with the presence of autoantibodies and abnormal cytokine profiles in first-degree relatives with asymptomatic left ventricular enlargement. These relatives suffer from a higher risk for the development of DCM after years. This suggests the involvement of a disrupted humoral and cellular immunity early in the development of the disease. There is reasonable clinical and experimental evidence, that DCM in addition may occur as late stage of cardiac infection and inflammation. The large spectrum of clinical forms depends on several factors such as genetic determinants of the infective agent, the genetics, age and gender of the host, and the host immunocompetence. In general, infectious agents, including viruses such as entero-, cytomegalo-, and adenoviruses, bacteria such as Borrelia burgdorferi or Chlamydia pneumoniae, protozoa and even fungi can cause inflammatory heart disease leading to DCM. The infectious agents most often identified in DCM nowadays are parvovirus B19, human herpesvirus 3, and Epstein-Barr virus. Persistence of these viruses within the myocardium is associated with reduction of ejection fraction after 6 months. For patients with suspected inflammatory heart disease the immunohistochemical detection of inflammatory infiltrates is related to poor outcome. Many faces of inflammatory heart disease coexist where different phases of the disease progress simultaneously: phase 1 is dominated by viral infection itself, phase 2 by the onset of (probably) multiple autoimmune reactions, and phase 3 by the progression to cardiac dilatation. Further investigations with regard to the etiology of structural heart diseases should include an intensive clinical investigation of the given patient. A possible family history including a pedigree should be ascertained and with regard to a possible inflammatory or viral heart disease, endomyocardial biopsies should be investigated by polymerase chain reaction and immunohistochemistry.

[Severe myocardial damage caused by leptospirosis. Report of a fatal case in Mexico]. / Daño miocárdico grave por leptospirosis. Informe de un caso fatal en México.

Chagasic cardiomyopathy is a common disease in Latin America, however similar clinical pictures exist that can be confused with this, as they give negative results to the tests that detects T. cruzi, like non Chagasic rural endemic chronic cardiopathy, highly common in Venezuela. Using histopathology techniques, "idiopathic cardiomyopathy" is frequently found as the cause of death when the etiology of this disease is not known. This paper presents the case of a man of 26-years-old who died of dilated cardiomyopathy secondary to leptospirosis. Clinically, in addition to the cardiac failure, jaundice, hyperbilirubinemia, transaminases increase, proteinuria and hematuria were present. Initially it was suspected Chagasic cardiomyopathy but the epidemiologic background and the parasitologic and serologic tests for T. cruzi gave negative results. The dark field microscopy videorecording of blood and urine samples, argentic impregnation and immunohistochemistry tests as well as haemoculture in EMJH medium were positive for L. interrogans serovar Pomona. Postmortem we confirmed the presence of leptospira in different tissues through of histopathology, argentic impregnation, indirect immunofluorescence and immunohistochemistry.

[Lyme carditis--rare cause of dilated cardiomyopathy and rhythm disturbances]. / Lymeská karditida--vzácná prícina dilatacní kardiomyopatie a poruch srdecního rytmu.

Case report of young woman presents involvement of dilated cardiomyopathy and rhythm disturbances in 18 months after infection of tick, with direct assessment of spirochetes in myocardial tissue. Cardial decompensation occured after asthma exacerbation, complicated by bronchopneumonia. Rhythm disturbances and heart failure gradually subside after parenteral antibiotic treatment and peroral treatment of heart failure. Nevertheless there is a long-lasting persistence of dilated cardiomyopathy with significant systolic dysfunction, which is supposedly last consequence of Borrelia infection. Resynchronic therapy combinated with cardioverter-defibrilator primary considering was postponed for improvement clinical condition and myocardial electric stability. There is demonstrating complicated serologic diagnostics of Lyme disease in discussion. Lyme carditis would be part of differential diagnosis in rhythm disturbances and cardiomyopathy of unknown etiology, including serious or fatal events.

Significance of Borrelia infection in development of dilated cardiomypathy (a pilot study).

A heart involvement known as Lyme carditis (LC), a consequence of Lyme borreliosis (LB), is relatively rare in contrast to the involvement of skin, joints and nervous system; it accounts for < 4% of all these patients in European countries. However, the diagnosis of the disease belongs to the most difficult challenges. While various forms of AV blocks dominate in the USA as confirmed by the literature, there is a clear predominance of arrhythmias of various incidence in the Czech Republic. The authors of this article focused on the form belonging to the rarest manifestations of LC, namely dilated cardiomyopathy (DCMP). The goal was to elucidate the etiological participation of Borrelia infection in the development of DCMP, which has attracted controversial opinions so far. In total, 33 patients with DCMP were enrolled in the study, 23 males and 10 females, with mean age 57.7 years (range 24-76 years). ELISA NRLB KC 90 method was used in all blood samples for detection of Borrelia infection (BI), Western blot method was used for confirmation, followed by identification of DNA of pathogenic Borreliae using PCR method. Bioptic material was examined by electronmicroscopy with an attempt to detect Spirochaetae in myocardium. 16 patients were excluded from the study owing to the absence of signs of LB. The study group included 17 patients (3 females, 13 males) with mean age 58 years (range 43-76 years), in whom the presence of Bb was proved by identification of DNA of pathogenic Borreliae or by electronmicroscopic detection of Spirochetae in myocardial bioptic sample. The findings obtained during the study confirmed that BI very probably participated in the development of dilated cardiomyopathy. It may be concluded that most of cases were either unapparent forms of LB or insufficiently treated cutaneous forms of this disease.

[Cardiac abnormalities of lyme borreliosis]. / Postizení srdce v prubehu lymeské borreliózy.

The article summarizes basic characteristics of Lyme borreliosis, its incidence, epidemiology, pathogenesis and clinical image. Particular attention is given to the review of papers aimed at the cardiac abnormalities--the Lyme carditis. Though they are not very frequent, due to the variability of their clinical course and due to various forms, which are difficult to diagnose, they can represent a specific problem. Major part of the article is given to the authors' own experience with the dilated cardiomyopathy of the Borrelia origin and namely to the perspective study of the patients after the skin form of the disease erythema migrans, who were treated "lege artis" in the early phase of the disease with antibiotics. Authors were interested how many of those patients would develop later the cardiac abnormalities.