Microcirculation Dysfunction in Hypertrophic Cardiomyopathy

Background:Hypertrophic cardiomyopathy (HCM) is defined by the presence of left ventricular(LV)hypertrophy that cannot be solely explained by an increased afterload. The pathophysiologic mechanisms of this disease include coronary microvascular dysfunction and ischemia. The microvascular dysfunction is multifactorial, including reduced capillary density and vascular remodelling, fibrosis, myocyte disarray, and extravascular compression. Chronic and recurrent myocardial ischemia leads to fibrosis, which may culminate in myocardial dysfunction. Despite the recognition of microvascular dysfunction in HCM, further investigation is needed to delineate the interrelationships between microvascular dysfunction,fibrosis and prognosis.Objectives:The present research aimed to study the coronary microvascular dysfunctionin HCM using a multimodality approach, in order to identify predictors of microvascular dysfunction and to assess the association between microvascular dysfunction withtissue abnormalities and clinical manifestations. Methods:This prospective study enrolled83adult patients with HCM,withoutobstructiveepicardial coronary artery disease, submitted to the assessment of coronary microcirculation by:Echocardiography to evaluatecoronary flow velocity reserve (CFVR)(normal cut-off value ≥2.0), during adenosine-induced hyperemia;CMRto assess the ischemic burden by perfusion imaging during regadenoson-induced hyperemia;Cardiac catheterization to determine index of microcirculatory resistance(IMR)(normal cut-off value ≤22.0) and coronaryflow reserve (CFR) (normal cut-off value ≥2.0), during adenosine-induced hyperemia.Echocardiographic protocol included the assessment of myocardial deformation by two-dimensional(2D)longitudinal strain and three-dimensional(3D)longitudinal, circumferential and radial strain, area strain, torsion and twist.CMR protocol also included parametric mapping(to assess native T1, extracellular volume (ECV) and T2), late gadolinium enhancement (LGE) and three-dimensional longitudinal, circumferential and radial strains analysis.12-lead electrocardiogram, 24 hours Holter recording and cardiopulmonary exercise testing (CPET) were performed to assess arrhythmias and functional capacity. Results:EchocardiographyEighty-three patients underwent echocardiographic study. Mean age 55.0(14.4)years,50(60%)patientswere male; 59(71%) had nonobstructive HCM.CFVRin the left anterior descending artery(LAD)was 1.81(0.49) and CFVRin the posterior descending(PD)was 1.73(0.55); CFVR LAD was 15% (area under the curve0.766,sensitivity 0.724, specificity 0.659). Ischemia was also associated with atrial fibrillation/flutter (AF/AFL) (OR:1.481,95%CI:1.020,2.152,p=0.039), but no association was seen for nonsustained ventricular tachycardia. Ischemia was associated with shorter time to anaerobic threshold in CPET (β-estimate:-0.442,95%CI:-0.860,-0.023,p=0.039).Cardiac catheterizationFourteen patientsunderwent cardiac catheterizationwith a mean age of62.8(6.2)years, 8 (57.1%) males, 9 (64.3%) of whom had obstructive HCM. Among 4 patientswith an IMR >22.0, all had nonobstructive HCM and 2 had angina. CFR22.0, perfusion defects were found in 2 of the 3 patients who underwent stress CMR.Increased ECV (>28%) was documented in2 of the patients with IMR>22 and in 3 of the patients with IMR≤22.0.LGE was >15% in 2 of the patients with IMR>22 and in 4 with IMR≤22.0. Conclusions: Coronary microvascular dysfunction isafrequentpathophysiological finding in HCM, and its evaluation has clinical relevance. In our cohort, greater MWT was linkedto depressed CFVR, and blunted CFVR associated with impaired biventricular systolic function and worse functional capacity.Ischemic burden, secondary to microvascular dysfunction, wasrelated to the severity of LV hypertrophy and impacts on various pathological and clinical features, includingtissue abnormalitiesandarrhythmic events.IMR assessment inHCMisfeasible and safe. Patients with abnormal IMR seemed to havemore significant tissue abnormalities in CMR.Our findings highlight the potential additional role of the evaluation ofcoronary microvascular dysfunction in patients with HCM,which may allow more accuraterisk stratificationfor arrhythmic events and progression to heart failure

Arrhythmogenic Left Ventricular Cardiomyopathy: A Successful Case of Extracorporeal Cardiopulmonary Resuscitation

A 24-year-old man suffered a witnessed cardiac arrest after a padel game. Basic life support was immediately provided. The pre-hospital emergency services team continued the resuscitation efforts, and the patient was accepted for extracorporeal cardiopulmonary resuscitation. The return of spontaneous circulation was achieved in 45 minutes. The initial assessment revealed a ST-segment elevation in leads V4-V6 and a dilated left ventricle with severe systolic dysfunction. Coronary angiography was normal. An improvement in left ventricular systolic function was observed and extracorporeal cardiac support was discontinued after 48 hours. Cardiovascular magnetic resonance imaging demonstrated hypokinesia and subepicardial fatty infiltration of the left ventricle lateral wall. Genetic testing detected a variant of uncertain significance in the ANK2 gene. The diagnosis of arrhythmogenic left ventricular myocardiopathy did not fulfill all the current diagnostic criteria, but it is a very likely diagnosis. An implantable cardioverter-defibrillator was placed. The patient was discharged without physical or cognitive impairment

Cardiac sarcoidosis presenting as sustained ventricular tachycardia

Introduction: Sarcoidosis has many possible clinical presentations since it can affect any organ, most commonly the lungs. The hallmark of the disease consists of the formation of non-necrotising granulomas. Pathogenesis is thought to rely on the interplay of genetic, environmental and epigenetic factors. This case highlights the importance of a thorough clinical history and physical examination, and the correlation with imaging findings in the diagnostic work-up of the non-ischaemic cardiomyopathy. Case description: A 57-year-old woman was admitted due to the sudden onset of malaise, dizziness, and chest discomfort. Sustained monomorphic ventricular tachycardia was evidenced and the patient rapidly evolved with haemodynamic instability; she underwent successful electrical cardioversion. The electrocardiogram afterwards showed a high-risk electrocardiographic pattern. Invasive coronary angiography excluded obstructive epicardial coronary lesions. Physical examination revealed skin lesions on the lower limbs which raised suspicion for erythema nodosum and therefore a biopsy was performed. Transthoracic echocardiography and cardiac magnetic resonance imaging revealed features consistent with an inflammatory cardiomyopathy, and an implantable cardioverter-defibrillator was placed. The histologic examination of the cutaneous lesions showed a non-necrotising granulomatous inflammatory process. Radionuclide imaging was inconclusive. The patient underwent an endomyocardial biopsy, which confirmed the diagnosis of systemic sarcoidosis with cardiac involvement. Conclusions: Systemic sarcoidosis with cardiac involvement is a challenging diagnosis. The role of imaging techniques such as transthoracic echocardiography, cardiac magnetic resonance imaging and radionuclide imaging is essential in raising suspicion and diagnosing this pathology. Endomyocardial biopsy is the ‘gold standard’ for its diagnosis; however, it has a low diagnostic yield

Digestibilidade total e desempenho de bezerras lactentes da raça Holandesa com adição de própolis na dieta

The objective of the present study was to evaluate the effect of  addition of propolis based products  (LLOSA2 and LLOSC1) at two concentrations of propolis (A and C) and two alcoholic contents (1 and 2,) towards the use of lasalocid sodium (positive control) in total tract digestibility and performance of Holstein heifers fed from birth to weaning (60 days) with milk and concentrate diet (20% crude protein). It was used a completely randomized design with three treatments and ten repetitions for performance evaluation, and four replications to estimate the total tract digestibility of the diets at 5% significance level. There was no effect (P>0.05) of the tested additives on dry matter intake of heifers (1048.5 g/day), average daily weight gain (711.3 g/day) and feed conversion (1.5). Similarly, no significant difference (P>0.05) of additives was observed on the digestibility of dry matter (77.4%), crude protein (79.0%) and ether extract (96.9%). Thus, data suggest that the additives based on propolis can be used in replacement of lasalocid in Holstein heifers, as the additives based on propolis did not cause any damage to the nutrient intake, performance, feed conversion and total tract digestibility of tested diets.Objetivou-se avaliar o efeito da adição de produtos à base de própolis (LLOSA2 e LLOSC1) em duas concentrações de própolis (A e C) e dois teores alcoólicos (1 e 2) frente ao uso de lasalocida sódica (controle positivo) na digestibilidade total e desempenho de bezerras Holandês Preto e Branco alimentadas do nascimento ao desmame (60 dias) com leite e  ração concentrada (20% de proteína bruta). Utilizou-se delineamento experimental inteiramente casualizado com três aditivos e dez repetições para avaliação do desempenho; e quatro repetições para a estimativa da digestibilidade total das dietas ao nível de 5% de significância.  Não houve efeito (P>0,05) dos aditivos testados sobre o consumo de matéria seca das bezerras (1048,5 g/dia), ganho de peso médio diário (711,3 g/ dia) e para conversão alimentar (1,5). Do mesmo modo, não houve diferença significativa (P>0,05) dos aditivos sobre as digestibilidades de matéria seca (77,4%), proteína bruta (79,0%) e extrato etéreo (96,9%). Assim, os aditivos à base de própolis podem ser utilizados na substituição da lasalocida sódica em bezerras lactentes Holandês, pois os mesmos não causaram nenhum prejuízo ao consumo de nutrientes, desempenho, conversão alimentar e digestibilidade das dietas testadas

Educomunicação e diversidade: tecendo saberes

Com esta publicação Educomunicação e Diversidade: Tecendo Saberes, a Associação Brasileira de Pesquisadores e Profissionais de Educomunicação socializa uma importante contribuição para o aprofundamento e aprimorando de estudos e práticas educativas e comunicativas numa perspectiva de respeito às diversidades. A publicação está estruturada em quatro partes, a saber: I. Educomunicação e Políticas para a Cidadania; II. Práxis Educomunicativa: o principio da indissociabilidade entre ensino-pesquisa-extensão; III. Educomunicação e Formação em EAD; IV – Mediação Tecnológica. Trata-se, assim, de um trabalho coletivo que contém 19 capítulos onde contribuem 35 autores e coautores. Eis uma publicação que se destina não somente aos educomunicadores, mas a todos os que assumem o desafio de pensar numa outra forma possível de educar e de comunicar, mais colaborativa, intercultural, criativa e emancipatória, menos colonizadora e arrogante. Desejamos à leitora-interlocutora, ou ao leitor-interlocutor, uma leitura prazerosa, crítica e problematizadora dessa publicação que se  apresenta como um ensaio, mas com a pretensão e o potencial de contribuir para o avanço dos estudos em torno do campo de interface entre Comunicação e Educação, sempre com o imprescindível respeito às diversidades

The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability

Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications