Patologia do bloqueio atrioventricular na cardiomiopatia por depósito de desmina / Atrioventricular block pathology in cardiomyopathy by desmin deposition / Patología de bloqueo auriculoventricular en la miocardiopatía por depósito de desmina

Geralmente, a cardiomiopatia restritiva por deposição de desmina é caracterizada pela restrição ao enchimento diastólico ventricular e por diferentes graus de bloqueio atrioventricular (BAV). Neste relato, são descritas as alterações anatomopatológicas do sistema de condução cardíaco relacionadas ao BAV. O nó sinusal, o nó compacto e o feixe penetrante (feixe de His) não apresentavam anormalidades, entretanto, havia extensa fibrose das porções terminais do feixe ramificante e do início dos feixes esquerdo e direito, no topo do septo ventricular. A patogenia dessa substituição fibrosa é provavelmente a mesma que origina a extensa fibrose do miocárdio ventricular contrátil, e permanece por ser elucidada.

Generally, restrictive cardiomyopathy due to desmin deposition is characterized by restriction to ventricular diastolic filling and different degrees of atrioventricular block (AVB). In this report, we describe the pathological changes of the cardiac conduction system related to AVB. The sinus node, the compact node, and the penetrating bundle (bundle of His) had no abnormalities, however, there was extensive fibrosis of the terminal portions of the branching bundle and the beginning of the left and right bundles at the top of the ventricular septum. The pathogenesis of this fibrous replacement is probably the same that leads to extensive fibrosis of the working ventricular myocardium, and remains to be elucidated.

En general, la miocardiopatía restrictiva, debido a la deposición de desmina se caracteriza por la restricción de llenado diastólico ventricular y por los distintos grados de bloqueo auriculoventricular (BAV). En este informe, se describen los cambios anatómicos y patológicos del sistema de conducción cardiaco relacionado con BAV. El nodo sinusal, el nodo compacto y haz penetrante (haz de His) no tuvo alteraciones, sin embargo, había fibrosis extensa de las porciones terminales del haz en porción ramificante y del comienzo de los haces izquierda y derecha, en la parte superior del tabique ventricular. La patogenia de esta sustitución fibrosa es probablemente la misma que origina la fibrosis extensa del miocardio ventricular contráctil, y queda por dilucidar.

Relationship between the increase of fibrous and fatty in atrioventricular node and narrowing of the atrioventricular node artery / 法医学杂志

OBJECTIVE@#To explore relationship between increase of fibrous and fatty in atrioventricular node (AVN) and narrowing of the AVN artery. To analyze the cause of pathological fibrosis and fatty infiltration in AVN.@*METHODS@#One hundred and nineteen cases of sudden cardiac death determined by autopsy were selected and the histological sections were examined with Image-pro plus software to calculate the AVN area, AVN artery inside-diameter, AVN artery lumen area(LA) , AVN artery perimeter area(PA), fibrous area and fatty area. All cases were divided into two groups: narrowing of artery group and normal control group. The changes of the PA/LA value and the fibrous and fatty contents were evaluated.@*RESULTS@#The PA/LA value is the highest in 21-40 age group. The difference of the fatty contents and total interstitial tissue was statistical significance in the two groups under 40 years of age.@*CONCLUSION@#There is some relationship between the narrowing of the AVN artery and the increase of interstitial contents in AVN.

Frequency and clinical outcome in conduction defects in acute myocardial infarction

Conduction defects complicating acute myocardial infarction [MI] are frequent and associated with increased mortality and complications. Common conduction defects after acute MI are atrioventricular nodal blocks [1[st], 2[nd] and 3[rd] degree] and intraventricular conduction defects [right or left bundle branch blocks and hemiblocks]. In myocardial infarction occlusion of coronary arteries at different levels affects the conduction system of heart leading to various types of blocks. Conduction defects usually reflect extensive damage to the myocardium. In this descriptive case series with non-probability purposive sampling, 345 cases of acute ST elevation myocardial Infarction were studied at Armed Forces Institute of Cardiology/National Institute of Heart Disease, Rawalpindi from May 2007 to May 2008. ECG was continuously observed in CCU and daily ECGs were done. Conduction defects whether transient or persistent were recorded in pre-designed proforma in addition to other clinical features and associated complications during hospital stay. Out of 345 patients. 251 [72.8%] patients received thrombolytic therapy and 61 [17.6%] developed various types of conduction defects [Group A] and 284 had no significant conduction defects [Group B]. Isolated complete atrioventricular block [AVB] at the node level occurred in 28 patients [8.1%] mainly in inferior MI. Bundle branches Blocks occurred in 32 [9.2%] patients mostly in Anterior MI. One patient [0.6%] had complete heart block at bundle branch level. All patients with complete atrioventricular block reverted to sinus rhythm except one who required permanent pacemaker. Mortality rate and clinical complications were higher in group A as compared to group B. Conduction defects are common even in this thrombolytic era. Patients with conduction defects are at high risk of inhospital complications and mortality. They need close monitoring and optimum clinical care to reduce mortality and morbidity

Prevalencia, características electrocardiográficas y localización de las vías accesorias en el Wolff-Parkinson-White sobre una población de 24.000 individuos aparentemente sanos / Prevalence, Electrocardiographic characteristics and localization of accesory connections of the wolff-Parkinson-White syndrome in a population of 24.000 apparently healthy subjects

El síndrome de preexcitación tiene una larga e interesante historia, esta anormalidad electrocardiográfica fue descripta por Wolff-Parkinson-White y una conexión AV accesoria resulta ser su sustrato anatómico. Sin embargo, aun después de la documentación de estas vías accesorias, la búsqueda de mecanismos alternativos para explicar la preexcitación continuó. Finalmente, el estudio electrofisiológico y la terapia quirúrgica o ablativa confirmó la teoría. Las distintas publicaciones hacen referencia a disímiles frecuencias de presentación, dependiendo particularmente de la población de estudio.

Conduction disturbances in acute myocardial infarction: incidence, site-wise relationship and the influence on in-hospital prognosis.

The study was designed to assess the incidence of conduction disturbances, the relationship of the site of infarction with the type of conduction disturbances and the influence of conduction disturbances on the in-hospital prognosis. One hundred consecutive patients (M:F = 89:11) with a age range of 35-60 years with the history of first attack of acute myocardial infarction were included in the study. There were 45 anterior, 43 inferior and 12 combined anterior and inferior myocardial infarction patients. 44 of the patients had some type of conduction disturbances (Group A) and 56 had none (Group B). Inferior myocardial infarction patients showed higher incidence of conduction disturbances than anterior myocardial infarction (56.8% and 31.8% respectively) (Odd's ratio 2.98, 95% ci 1.14 to 7.9). Conduction disturbances were mostly (92%) atrio-ventricular in inferior myocardial infarction and mostly (72%) intraventricular in anterior myocardial infarction. Of the 13 cases of complete atrioventricular block, 8 had inferior, 2 anterior and 3 combined anterior and inferior infarction. In inferior infarction, complete atrioventricular block developed gradually through 1 degree and 2 degrees atrioventricular block but in the anterior infarction it developed suddenly. Patients with conduction disturbances developed more complications (84%) than those without conduction disturbances (54%). Mortality rate was higher in Group A (25%) than in Group B (3.6%) (Odd's ratio 9.0, 95% ci 1.76 to 86.73) with a overall rate of 13%. Mortality rate was higher in anterior myocardial infarction (50%) than in inferior myocardial infarction (25%) when complicated by complete atrioventricular block. It was concluded that conduction disturbances are predominantly atrioventricular in inferior and intra-ventricular in anterior MI; conduction disturbances are associated with increased risk of complications and death. Anterior location of MI may have an independent risk attribute.

Contribuiçäo ao conhecimento da cardiopatia chagásica aguda: estudo sistematizado dos sistemas excito-condutor e nervoso autônomo intracardíaco em caso autóctone do Acre / A contribution to the knowledge of acute chagasic cardiopathy: a systematized study of the conducting system and the autonomic intracardiac nervous system in an autochthonous case in Acre

The histopathology of the heart is described in an acute case of Chagas' disease (DC). Lesions involving the conducting system (SC) and the autonomic intracardiac nervous system (SNAIC) are emphasized. Light microscopy showed acute pan-carditis with plenty of Trypanosoma cruzi amastigotes within heart muscle cells. Multiple inflammatory foci were found in the SC with parasitic nests within the atrioventricular node and left his bundle. There were also severe atrial periganglionitis and perineuritis with or without peripheral involvement of those structures. Apparently there was no cardiac neuronal depopulation. The epidemiological study suggested transmission through Rhodnius pictipes. To the best of our knowledge, this is the first reported case of acute DC from the Amazonian basin with systematized microscopy study of the SC and SNAIC.

Cardiopatia chagásica crônica causando insuficiência cardíaca congestiva na infância: estudo clínico e histopatológico de um caso, com ênfase para as lesöes dos sistemas excito-condutor e nervoso autônomo intracardíaco / Chronic Chagas' cardiopathy causing congestive heart failure in childhood: a clinical and histopathological study of a case with emphasis on the lesions of the intracardiac conduction and autonomic nervous systems

Descreve-se caso de cardiopatia chagásica em menino de nove anos, natural e procedente do sul de Goiás, que desenvolveu insuficiência cardíaca congestiva quatro meses antes do óbito. As reaçöes sorológicas para doença de Chagas eram reagentes, e positivo o xenodiagnóstico. Os eletrocardiogramas mostraram taquicardia sinusal, extra-sístoles ventriculares e supraventriculares, hemibloqueio anterior esquerdo, bloqueio completo do ramo direito e sinais de sobrecarga de câmaras. O exame ecocardiográfico evidenciou dilataçäo de câmara com hipocontratilidade difusa. O quadro se agravou progressivamente, complicando-se por vários episódios pneumônicos, o último dos quais provocou o óbito. A necrópsia, verificou-se, no coraçäo, inflamaçäo crônica dos três folhetos, com miocardite crônica fibrosante predominando no septo interventricular e no ventrículo esquerdo. As estruturas componentes do sistema excito-condutor mostraram processo flogístico crônico, essencialmente exsudativo, ora discreto, ora moderado. No sistema nervoso autônomo constataram-se focos esparsos de discreta periganglionite crônica, e raros fenômenos degenerativos dos neurônios sem despopulaçäo neuronal

Cardiac changes implicated in chronic heart block.

Fifteen cases of chronic heart block were studied. Eight of them could be designated as idiopathic or primary heart block; the others were associated with hypertension, diabetes and ischaemic heart disease, either singly or in various combinations. In six cases, the whole heart was available for histopathological study of the conduction system. In the other 9 cases, only a portion of the heart muscle was available for examination. A V nodal fibrosis extending upto the proximal bundle of His was seen in all the six whole heart autopsy materials. Fibrosis of the adjacent myocardium was seen in five cases. In three cases, conducting system fibrosis was associated with atherosclerotic (1 case) or diabetic changes (3 cases) of the intramural vessels. In the 9 partial autopsy studies, myocardial fibrosis was seen in two cases, diabetic microangiopathy in one and atherosclerotic changes in two including an old thrombus in one. Thus, diabetic microangiopathy was seen in total four cases. These changes may be responsible for the cardiomegaly and cardiac failure associated with conduction defects observed in diabetes. In the idiopathic group also, heart block could be considered as a significant facet of a primary myocardial degenerative process.

Tuberculous pericarditis and the cardiac conduction system.

Nine cases of acute and 8 cases of chronic tuberculous pericarditis were studied for involvement of epicardial structures such as the S-A node, A-V node and large coronary arteries. Extensive caseation was seen in the region of the S-A node in 2 cases of chronic and one case of acute pericarditis. No nodal tissue was identifiable in these cases. In one more case of chronic pericarditis, granuloma with fibrosis was seen in the S-A node. Minor mononuclear infiltration of the S-A node was seen in 2 cases. In the rest of the cases, the S-A node was normal though inflammation was very close to it in 4 cases of acute and all the cases of chronic pericarditis. The A-V node, bundle of His and coronary arteries were normal in these cases.

The conduction system of the heart in mice chronically infected with Trypanosoma cruzi: histopathological lesions and electrocardiographic correlations

Em camundongos suiços näo isogênicos e em camundongos isogênicos das linhagens AKR e A/J, cronicamente infectados com cepas do Trypanosoma cruzi representativas de três tipos biológicos (Tipos I, II e III) foi observada uma miocardite crônica difusa e focal com graus variáveis de fibrose intersticial. Observou-se alta incidência de alteraçöes eletrocardiográficas com predominância de distúrbios da conduçäo intraventricular, bloqueios A-V de 1§ e 2§ graus e arritmias, comparáveis às encontradas na doença de Chagas humana. O estudo histopatológico do sistema de conduçäo do coraçäo mostrou alteraçöes inflamatórias e fibróticas. A presença de inflamaçäo no septo inter-atrial em geral coincidiu com o envolvimento do sistema de conduçäo pelo processo inflamatório. Os infiltrados inflamatórios estavam em geral associados com vacuolizaçäo e necrose focal das fibras do tecido específico. As lesöes foram mais freqüentes no feixe de His (76,3% dos casos), no ramos direito do feixe de His (73,3%), no nódulo AV (43,0%) e no ramo esquerdo do feixe de His (37,5%). Houve coincidência entre a presença de lesöes do sistema de conduçäo e de alteraçöes eletrocardiográficas, em 53 a 62,5% dos casos, de acordo com o grupo experimental

Bloqueo atrioventricular completo con doble interrupción del sistema conductor / Complete atrioventricular block with double interruption of the conduction system

Se presenta el caso de un bloqueo A-V congénito aislado en una niña de cuatro meses de edad, nacida de parto prematuro con asfixia neonatal. El examen anátomo-patológico demostró: nódulo A-V bien conformado, dos interrupciones fibrosas del haz de His: una en el segmento perforante y la otra en el segmento ramificado; entre ambas, un segmento de haz de His sin fibras musculares específicas y sólo con tejido conjuntivo, en el tejido fibroso circundante, algunos depósitos calcáreos. Se discute la patogenia de las lesiones encontradas en relación con las ideas actuales sobre el desarrollo del sistema éxcito-conductor del hombre. Se concluye que las lesiones descritas no corresponden a las descritas en los casos de bloqueo por trastornos del desarrollo embrionario, y que probablemente ellas con el resultado de un proceso degenerativo que afectó secundariamente a estas estructuras. Se considera la posibilidad de que dicho proceso haya la hipoxia neonatal con consecuente necrosis electiva del parénquima específico. Según la bibliografía revisada, el caso comunicado es el primero con dos interrupciones del sistema A_V

Inervaçäo do coraçäo a partir de um plexo abdominal no homem / Innervation of the heart from an abdominal plexus in men

E feito, em 43 peças de necropsia de indivíduos adultos, por meio de dissecçäo e de métodos histológicos usuais de coloraçäo e de impregnaçäo argêntica, estudo do conjunto formado pelo ligamento venoso, veia cava inferior e átrio direito. Os resultados indicam a presença de conexäo nervosa direta entre o plexo hepático e o átrio direito, feita por via que corre pelos ramos esquerdos da a. hepática e v. porta, ligamento venoso, ramo esquerdo da v. hepática e v. cava inferior atravessando o diafragma pelo forame da v. cava. Esta conexäo se processa por ramos nervosos muito finos da parte superior do ligamento venoso, visíveis apenas em nível microscópico

Sistema de conduçäo do coraçäo na doença de Chagas / System of conduction of the heart in Chagas' disease

Estudia la patología del sistema exitoconductor del corazón, en humanos con cardiopatía crônica chagásica y en perros con infección aguda y crónica por Trypanosoma cruzi. Describe las lesiones encontradas en las distintas fases de la enfermedad: en la fase aguda: daño miocárdio, lesiones inflamatorias, isquemia y bloqueo cardíaco; en la forma crónica indeterminada: miocarditis focal discreta y fibrosis focal cicatricial; y, en la miocardiopatía crónica chagásica: lesiones en el nódulo S-A y en el sistema A-V; y bloqueo auriculoventricular. Comenta el aneurisma apical del ventrículo izquerdo -característico de la cardiopatía chagásica-, que parece representar una manfiestación dependiente de las lesiones que afectan al sistema de conducción cardíaca

Estudios electrofisiológicos en la miocarditis chagásica crónica / Electrophysiological studies in the chronic Chagasic myocarditis

Los estudios electrofisiológicos sond e utilidad en el diagnóstico y reconocimiento de las arritmias en general y de la miocarditis chagásica crónica, permitiendo conocer el origen de aquellas, el modo de activación intracardíaca del estímulo ectópico y su capacidad de generar taquiarritmias severas, la vulnerabilidad de los ventrículos a los estímulos ectrópicos, los trastornos en la conducción, su significación pronóstica, y el comportamiento frente a distintas drogas antiarritmicas para el tratamiento de pacientes; possibilitando la selección del tratamiento adecuado, evaluación de su efectividad, y, decisión de la eventual implantación de marcapasos definitivo. Se describen el equipamiento y métodos de los estudios electrofisiológicos, detallándose los registros que pueden obtenerse en ellos: recorrido de estímulos auriculares ectópicos y su origen; registrados de Haz de His y de potencial de acción monofásico -para establecer las variaciones presentadas en la administración de drogas antiarrítmicas-. También se consideran útiles, en pacientes con arritmias, los métodos de estimulación ventricular programada