Influence of idiopathic epilepsy on blood pressure and electrocardiography in dogs treated with phenobarbital.

Background and Aim: Dogs with idiopathic epilepsy (IE) experience a shortened lifespan, neurobehavioral changes, and an increased risk of comorbidities during the interictal period. There have been several reports of sudden death in humans with epilepsy, suggesting changes in cardiac rhythm secondary to seizures. In veterinary medicine, there are still no such conclusive studies. The present study aimed to evaluate blood pressure values, electrocardiographic findings, and laboratory parameters in dogs with IE treated with phenobarbital and to correlate these findings with possible cardiac alterations. Materials and Methods: Twenty-one dogs were divided into 11 healthy dogs and 10 idiopathic epileptic dogs for blood analysis, computerized electrocardiogram, and oscillometer-based blood pressure measurement. Results: QRS complex and S-T interval values differed significantly between groups, but blood pressure values were not significantly different. Conclusion: IE can occur with alterations in cardiac conduction and is a pathological condition.

Feasibility of Goal-Directed Fluid Therapy in Patients with Transcatheter Aortic Valve Replacement - An Ambispective Analysis.

INTRODUCTION: Goal-directed fluid therapy (GDFT) has been shown to reduce postoperative complications. The feasibility of GDFT in transcatheter aortic valve replacement (TAVR) patients under general anesthesia has not yet been demonstrated. We examined whether GDFT could be applied in patients undergoing TAVR in general anesthesia and its impact on outcomes. METHODS: Forty consecutive TAVR patients in the prospective intervention group with GDFT were compared to 40 retrospective TAVR patients without GDFT. Inclusion criteria were age ≥ 18 years, elective TAVR in general anesthesia, no participation in another interventional study. Exclusion criteria were lack of ability to consent study participation, pregnant or nursing patients, emergency procedures, preinterventional decubitus, tissue and/or extremity ischemia, peripheral arterial occlusive disease grade IV, atrial fibrillation or other severe heart rhythm disorder, necessity of usage of intra-aortic balloon pump. Stroke volume and stroke volume variation were determined with uncalibrated pulse contour analysis and optimized according to a predefined algorithm using 250 ml of hydroxyethyl starch. RESULTS: Stroke volume could be increased by applying GDFT. The intervention group received more colloids and fewer crystalloids than control group. Total volume replacement did not differ. The incidence of overall complications as well as intensive care unit and hospital length of stay were comparable between both groups. GDFT was associated with a reduced incidence of delirium. Duration of anesthesia was shorter in the intervention group. Duration of the interventional procedure did not differ. CONCLUSION: GDFT in the intervention group was associated with a reduced incidence of postinterventional delirium.

Feasibility of Goal-Directed Fluid Therapy in Patients with Transcatheter Aortic Valve Replacement - An Ambispective Analysis

ABSTRACT Introduction: Goal-directed fluid therapy (GDFT) has been shown to reduce postoperative complications. The feasibility of GDFT in transcatheter aortic valve replacement (TAVR) patients under general anesthesia has not yet been demonstrated. We examined whether GDFT could be applied in patients undergoing TAVR in general anesthesia and its impact on outcomes. Methods: Forty consecutive TAVR patients in the prospective intervention group with GDFT were compared to 40 retrospective TAVR patients without GDFT. Inclusion criteria were age ≥ 18 years, elective TAVR in general anesthesia, no participation in another interventional study. Exclusion criteria were lack of ability to consent study participation, pregnant or nursing patients, emergency procedures, preinterventional decubitus, tissue and/or extremity ischemia, peripheral arterial occlusive disease grade IV, atrial fibrillation or other severe heart rhythm disorder, necessity of usage of intra-aortic balloon pump. Stroke volume and stroke volume variation were determined with uncalibrated pulse contour analysis and optimized according to a predefined algorithm using 250 ml of hydroxyethyl starch. Results: Stroke volume could be increased by applying GDFT. The intervention group received more colloids and fewer crystalloids than control group. Total volume replacement did not differ. The incidence of overall complications as well as intensive care unit and hospital length of stay were comparable between both groups. GDFT was associated with a reduced incidence of delirium. Duration of anesthesia was shorter in the intervention group. Duration of the interventional procedure did not differ. Conclusion: GDFT in the intervention group was associated with a reduced incidence of postinterventional delirium.

Eficácia da estimulação hissiana e septal profunda comparada à estimulação cardíaca convencional: revisão de literatura / Efficacy of hissian and deep septal stimulation compared to conventional cardiac stimulation: literature review

Introdução: Pacientes com insuficiência cardíaca e doenças do sistema de condução necessitam de dispositivos para monitoramento dos batimentos cardíacos, como marcapassos permanentes, dispositivos de ressincronização cardíaca ou cardiodesfibriladores implantáveis. A estimulação ventricular direita (EVD) é tradicionalmente o tratamento de escolha. No entanto, estudos demonstraram evidências de dissincronia ventricular, redução da função cardíaca, recorrência de fibrilação atrial e aumento da mortalidade associadas a esta abordagem. O conhecimento dos efeitos adversos das técnicas convencionais justifica a realização de pesquisas para determinar se a estimulação hissiana (EH) é uma técnica que produz maior ativação fisiológica e ventricular mais sincronizada. Objetivo: Avaliar a eficácia da estimulação hissiana comparada à EVD em relação aos parâmetros eletrocardiográficos, ecocardiográficos e clínicos.Material e Métodos: Os critérios de elegibilidade seguiram a estratégia PICOS: P ­ pacientes com indicação de dispositivos cardíacos eletrônicos implantáveis; I ­ estimulação hissiana; C ­ estimulação ventricular direita; O ­ duração do complexo QRS, fração de ejeção, diâmetro ventricular ou classe funcional da New York Heart Association (NYHA); S ­ ensaios clínicos controlados randomizados (ECR) e não randomizados. As buscas foram realizadas nas bases Medline via PubMed, Embase, LILACS e Cochrane Library, realizadas em março de 2023 por três revisores independentes. Resultados: Foram incluídos sete ensaios clínicos comparando as técnicas EH versus EVD quanto aos desfechos investigados. Para a duração do complexo QRS, três estudos encontraram resultado significativamente melhor no grupo intervenção. Para fração de ejeção e classe funcional da NYHA, dois estudos apresentaram resultados significativamente melhores no grupo EH. Quanto ao risco de viés, apenas dois apresentaram risco baixo e médio, quatro apresentaram risco alto em um, dois ou três dos itens avaliados. Conclusões: A técnica EH demonstrou superioridade à técnica convencional, entretanto são necessários ECR de maior qualidade metodológica e meta-análises para verificar a eficácia clínica da técnica, envolvendo maior número de pacientes e tempo de seguimento.

Introduction: Patients with heart failure and cardiac conditions require devices for monitoring the heartbeat, such as permanent pacemakers, cardiac resynchronization devices, or implantable cardioverter defibrillators. Right ventricular stimulation (RVP) has traditionally been the treatment of choice. However, studies have shown evidence of ventricular dyssynchrony, reduced cardiac function, recurrence of atrial fibrillation, and increased mortality associated with this approach. Recognizing the adverse effects of conventional techniques justifies conducting research to determine whether Hissian or His bundle pacing (HPB) stimulation can provide more physiologically synchronized ventricular activation. Objective: The aim is to assess the efficacy of Hissian stimulation compared to right ventricular pacing (RVP) in relation to electrocardiographic, echocardiographic and clinical parameters. Material and Methods: The eligibility criteria will follow the PICOS strategy: P ­ Patients with indication for implantable electronic cardiac devices; I ­ Hissan Stimulation; C ­ Right Ventricular Stimulation; O ­ QRS complex duration, ejection fraction, ventricular diameter and New York Heart Association (NYHA) functional class; S ­ Controlled Trials. Searches were conducted on the Medline via PubMed, Embase, Latin America and Caribbean Health Science Literature Database (LILACS) and Cochrane Library platforms. The searches were performed in March 2023 by three independent reviewers. Results: Seven clinical trials were included, comparing HPB versus RVP techniques regarding the investigated outcomes. For the QRS complex duration, three studies found a significantly better result in the intervention group. For ejection fraction and NYHA functional class, two studies had significantly better results in the HPB group too. Concerning the risk of bias, out of the seven studies included, only two presented low and medium risk, four presented high risk in one, two or three of the items evaluated. Conclusions: The HPB technique has demonstrated superiority to the conventional technique, however, RCT of higher methodological quality and meta-analysis are needed to verify the clinical effectiveness of the technique, involving more patients and longer follow-up time.

Relationship of the T-wave Tpeak-Tend interval with conduction system disorders in arterial hypertension / Relación del intervalo Tpico-Tfinal de la onda T con trastornos del sistema de conducción en hipertensión arterial

Abstract Purpose: The Tpeak-Tend interval of the T wave has emerged as a new electrocardiographic marker of increased transmural dispersion of ventricular repolarization. We aimed to determine the presence of cardiac conduction system disorders in patients with systemic arterial hypertension (SAH) who have altered Tpeak-Tend interval of the T wave. Methods: The 67 patients with SAH were divided into two groups. Those with prolonged (≥ 77 ms) Tpeak-Tend intervals, 21 (31%) patients were in the study group. Those with normal (< 77 ms) Tpeak-Tend intervals, 46 (69%) patients were in the control group. Alteration of ventricular repolarization manifested as a prolongation of the Tpeak-Tend interval was detected by computerized electrocardiographic analysis tools. Results: The median value of QRS complex duration was significantly wider in the study group as compared to the control group (110 ± 12 ms vs. 94 ± 8 ms p < 0.001). There was a significantly greater incidence of left anterior hemiblock in the study group (14% vs. 0% p < 0.04). The median value of the QTc interval was significantly greater in the study group (440 ± 26 vs. 422 ± 15 p < 0.01). There was a significantly greater incidence of patients with prolonged QTc interval in the study group (33% vs. 11% p < 0.02). The median value of the Tpeak-Tend interval was significantly greater in the study group (84 ± 5 ms vs. 65 ± 4 ms p < 0.001), as well as, the Tpeak-Tend/QTc ratio in the study group (0.19 ± 0.1 vs. 0.16 ± 0.1 p < 0.001). Conclusion: There is a significantly greater ventricular repolarization disorders and abnormalities of the cardiac conduction system in SAH patients who possess altered Tpeak-Tend interval of the T wave.

Resumen Objetivo: El intervalo Tpico-Tfinal de la onda T es un marcador electrocardiográfico de la dispersión transmural aumentada de la repolarización ventricular. Investigamos la presencia de trastornos del sistema de conducción cardíaca en pacientes con hipertensión arterial sistémica (HA) que poseen alterado el intervalo Tpico-Tfinal de la onda T. Métodos: Los 67 pacientes con HA fueron divididos en dos grupos. Aquellos con intervalos de Tpico-Tfinal prolongados (≥ 77 ms), 21 (31%) pacientes (grupo de estudio). Aquellos con intervalos normales (< 77 ms) Tpico-Tfinal, 46 (69%) pacientes (grupo control). Los intervalos Tpico-Tfinal fueron medidos por herramientas de análisis electrocardiográfico computarizado. Resultados: El valor mediano de la duración del complejo QRS fue significativamente más amplio en el grupo de estudio (110 ± 12 ms vs. 94 ± 8 ms p < 0.001). Hubo una incidencia significativamente mayor de hemibloqueo anterior izquierdo en el grupo de estudio (14% vs. 0% p < 0.04). El valor mediano del intervalo QTc fue significativamente mayor en el grupo de estudio (440 ± 26 vs. 422 ± 15 p < 0.01). Hubo una incidencia significativamente mayor de pacientes con intervalo QTc prolongado en el grupo de estudio (33% vs. 11% p < 0.02). El valor mediano del intervalo Tpico-Tfinal fue significativamente mayor en el grupo de estudio (84 ± 5 ms vs. 65 ± 4 ms p < 0.001), así como el cociente Tpico-Tfinal/QTc (0.19 ± 0.1 vs. 0.16 ± 0.1 p < 0.001). Conclusión: Existe una alteración de la repolarización ventricular significativamente mayor y anomalías del sistema de conducción cardíaca en pacientes con HA que poseen alteración del intervalo Tpico-Tfinal de la onda T.

Relationship of the T-wave Tpeak-Tend interval with conduction system disorders in arterial hypertension.

PURPOSE: The Tpeak-Tend interval of the T wave has emerged as a new electrocardiographic marker of increased transmural dispersion of ventricular repolarization. We aimed to determine the presence of cardiac conduction system disorders in patients with systemic arterial hypertension (SAH) who have altered Tpeak-Tend interval of the T wave. METHODS: The 67 patients with SAH were divided into two groups. Those with prolonged (≥ 77 ms) Tpeak-Tend intervals, 21 (31%) patients were in the study group. Those with normal (< 77 ms) Tpeak-Tend intervals, 46 (69%) patients were in the control group. Alteration of ventricular repolarization manifested as a prolongation of the Tpeak-Tend interval was detected by computerized electrocardiographic analysis tools. RESULTS: The median value of QRS complex duration was significantly wider in the study group as compared to the control group (110 ± 12 ms vs. 94 ± 8 ms p < 0.001). There was a significantly greater incidence of left anterior hemiblock in the study group (14% vs. 0% p < 0.04). The median value of the QTc interval was significantly greater in the study group (440 ± 26 vs. 422 ± 15 p < 0.01). There was a significantly greater incidence of patients with prolonged QTc interval in the study group (33% vs. 11% p < 0.02). The median value of the Tpeak-Tend interval was significantly greater in the study group (84 ± 5 ms vs. 65 ± 4 ms p < 0.001), as well as, the Tpeak-Tend/QTc ratio in the study group (0.19 ± 0.1 vs. 0.16 ± 0.1 p < 0.001). CONCLUSION: There is a significantly greater ventricular repolarization disorders and abnormalities of the cardiac conduction system in SAH patients who possess altered Tpeak-Tend interval of the T wave.

OBJETIVO: El intervalo Tpico-Tfinal de la onda T es un marcador electrocardiográfico de la dispersión transmural aumentada de la repolarización ventricular. Investigamos la presencia de trastornos del sistema de conducción cardíaca en pacientes con hipertensión arterial sistémica (HA) que poseen alterado el intervalo Tpico-Tfinal de la onda T. MÉTODOS: Los 67 pacientes con HA fueron divididos en dos grupos. Aquellos con intervalos de Tpico-Tfinal prolongados (≥ 77 ms), 21 (31%) pacientes (grupo de estudio). Aquellos con intervalos normales (< 77 ms) Tpico-Tfinal, 46 (69%) pacientes (grupo control). Los intervalos Tpico-Tfinal fueron medidos por herramientas de análisis electrocardiográfico computarizado. RESULTADOS: El valor mediano de la duración del complejo QRS fue significativamente más amplio en el grupo de estudio (110 ± 12 ms vs. 94 ± 8 ms p < 0.001). Hubo una incidencia significativamente mayor de hemibloqueo anterior izquierdo en el grupo de estudio (14% vs. 0% p < 0.04). El valor mediano del intervalo QTc fue significativamente mayor en el grupo de estudio (440 ± 26 vs. 422 ± 15 p < 0.01). Hubo una incidencia significativamente mayor de pacientes con intervalo QTc prolongado en el grupo de estudio (33% vs. 11% p < 0.02). El valor mediano del intervalo Tpico-Tfinal fue significativamente mayor en el grupo de estudio (84 ± 5 ms vs. 65 ± 4 ms p < 0.001), así como el cociente Tpico-Tfinal/QTc (0.19 ± 0.1 vs. 0.16 ± 0.1 p < 0.001). CONCLUSIÓN: Existe una alteración de la repolarización ventricular significativamente mayor y anomalías del sistema de conducción cardíaca en pacientes con HA que poseen alteración del intervalo Tpico-Tfinal de la onda T.

Repercusiones cardíacas en pacientes con pectus excavatum: puesta al día. Segunda parte / Cardiac repercussions in patients with pectus excavatum: update. Part two / Repercussões cardíacas em pacientes com pectus excavatum: atualização. Parte dois

El pectus excavatum (PEX) es una deformación de la pared torácica que obedece a una alteración de los cartílagos costales con el consiguiente hundimiento del esternón. Históricamente, se clasificaba como un defecto únicamente estético o cosmético, sin embargo, en los últimos años se han desarrollado nuevos métodos de estudio para la valoración de las repercusiones de esta patología. Existe cada vez más bibliografía que demuestra importantes repercusiones funcionales. Se realizó una puesta al día de las repercusiones cardíacas de la patología y un análisis de los artículos más relevantes de los últimos años. La evidencia actual permite afirmar que existe una afectación cardíaca por compresión esternal en la mayoría de los pacientes con PEX. Las afectaciones incluyen alteraciones anatomofuncionales (trastornos del ritmo, disminución del llenado ventricular), del volumen sistólico, aumento de la presión de la aurícula derecha, valvulopatías, compresión del ventrículo derecho, derrame pericárdico, entre otras. Todo lo cual permite concluir que el PEX puede presentar importantes alteraciones cardíacas que deben ser tenidas en cuenta a la hora de valorar los pacientes con esta patología.

Pectus excavatum (PEX) is a deformation of the chest wall caused by an alteration of the costal cartilages with the consequent collapse of the sternum. Historically, it had been classified as a solely aesthetic or cosmetic defect, however, in recent years new study methods have been developed to assess the repercussions of this pathology, with increasing bibliography showing important functional consequences. We updated the cardiac pathological repercussions and analyzed the most relevant articles of recent years. The current evidence suggests that there is cardiac involvement due to sternal compression in most patients with PEX. These affectations include anatomical functional alterations: rhythm disorders, decreased ventricular filling, decreased stroke volume, increased right atrial pressure, valve disease, right ventricular compression, pericardial effusion, among others. All of which enables us to conclude that PEX can present important cardiac alterations that must be taken into account when assessing patients with this pathology.

Pectus excavatum (PEX) é uma deformação da parede torácica decorrente de uma alteração das cartilagens costais com consequente colapso do esterno. Historicamente, foi classificado como um defeito exclusivamente estético ou cosmético, porém, nos últimos anos, novos métodos de estudo foram desenvolvidos para avaliar as repercussões dessa patologia, com crescente bibliografia mostrando importantes repercussões funcionais. Foi realizada uma atualização das repercussões cardíacas da patologia e análise dos artigos mais relevantes dos últimos anos. As evidências atuais permitem afirmar que há acometimento cardíaco por compressão esternal na maioria dos pacientes com PEX. As afecções incluem alterações anatomofuncionais: distúrbios do ritmo, diminuição do enchimento ventricular, diminuição do volume sistólico, aumento da pressão atrial direita, doença valvular, compressão do ventrículo direito, derrame pericárdico, entre outras. Tudo isso permite concluir que o PEX pode apresentar alterações cardíacas importantes que devem ser levadas em consideração na avaliação de pacientes com essa patologia.

Dependência de Pacing a Longo-Prazo e Preditores de Implante de Pacemaker após Implante Percutâneo de Prótese Valvular Aórtica - 1 Ano de Seguimento / Long-Term Ventricular Pacing Dependency and Pacemaker Implantation Predictors after Transcatheter Aortic Valve Replacement - A 1-Year Follow-Up

Resumo Fundamento Os distúrbios de condução (DC) são a complicação mais frequente após a substituição da válvula aórtica transcateter (TAVR) e ainda não há consenso sobre seu tratamento. Objetivo Avaliar novos DC e implante de marca-passo definitivo (MPD) após a TAVR e avaliar a porcentagem de estimulação ventricular (EV) até 1 ano de acompanhamento. Métodos Pacientes submetidos a TAVR de outubro de 2014 a novembro de 2019 foram cadastrados; pacientes com MPD anterior foram excluídos. Dados clínicos, do procedimento, do ECG e do MPD foram coletados até 1 ano após o implante. O nível de significância adotado para a análise estatística foi 0,05%. Resultados Um total de 340 indivíduos foram submetidos a TAVR. O DC mais comum foi bloqueio de ramo esquerdo novo (BRE; 32,2%), sendo que 56% destes foram resolvidos após 6 meses. O bloqueio do ramo direito (BRD) foi o maior fator de risco para bloqueio atrioventricular avançado (BAV) [RC=8,46; p<0,001] e implante de MPD [RC=5,18; p<0,001], seguido de BAV de baixo grau prévio [RC=2,25; p=0,016 para implante de MPD]. Em relação às características do procedimento, válvulas de gerações mais recentes e procedimentos de válvula-em-válvula foram associados a menos DC. No total, 18,5% dos pacientes tiveram MPD implantado após a TAVR. Na primeira avaliação do MPD, pacientes com BAV avançado tinham uma porcentagem mediana de EV de 80%, e, após um ano, de 83%. Em relação aos pacientes com BRE e BAV de baixo grau, a EV mediana foi mais baixa (6% na primeira avaliação, p=0,036; 2% após um ano, p = 0,065). Conclusão O BRE foi o DC mais frequente após a TAVR, com mais da metade dos casos se resolvendo nos primeiros 6 meses. O BRD foi o principal fator de risco para BAV avançado e implante de MPD. O BAV avançado foi associado a uma porcentagem mais alta de EV no acompanhamento de 1 ano.

Abstract Background Conduction disturbances (CD) are the most frequent complication after transcatheter aortic valve replacement (TAVR), and there continues to be a lack of consensus on their management. Objective To assess new CD and permanent pacemaker (PPM) implantation after TAVR and to evaluate the ventricular pacing percentage (VP) up to 1 year of follow-up. Methods Patients who underwent TAVR from October 2014 to November 2019 were enrolled; patients with previous PPM were excluded. Clinical, procedure, ECG, and PPM data were collected up to 1 year after implantation. The significance level adopted in the statistical analysis was 0.05. Results A total of 340 patients underwent TAVR. The most frequent CD was the new left bundle branch block (LBBB; 32.2%), which 56% resolved after 6 months. Right bundle branch block (RBBB) was the biggest risk factor for advanced atrioventricular block (AVB) [OR=8.46; p<0.001] and PPM implantation [OR=5.18, p<0.001], followed by previous low-grade AVB [OR=2.25; p=0.016 for PPM implantation]. Regarding procedure characteristics, newer generation valves and valve-in-valve procedures were associated with fewer CDs. Overall, 18.5% of patients had a PPM implanted post-TAVR. At first PPM evaluation, patients with advanced AVB had a median percentage of VP of 80% and 83% at one year. Regarding patients with LBBB plus low-grade AVB, median VP was lower (6% at first assessment, p=0.036; 2% at one year, p = 0.065). Conclusion LBBB was the most frequent CD after TAVR, with more than half being resolved in the first six months. RBBB was the major risk factor for advanced AVB and PPM implantation. Advanced AVB was associated with a higher percentage of VP at 1 year of follow-up.

Asociación entre interleuquinas inflamatorias y la presencia de trastornos intraventriculares de la conducción en pacientes con serología positiva para enfermedad de Chagas y función ventricular conservada / Association between inflammatory interleukins and intraventricular conduction disturbances in patients with positive serology for Chagas disease and preserved ventricular function

RESUMEN Introducción: Los trastornos intraventriculares de la conducción constituyen una manifestación habitual en los pacientes con enfermedad de Chagas con función ventricular izquierda conservada. Se desconoce si su presencia puede estar asociada a una mayor actividad inflamatoria. Objetivos: Determinar si existe una correlación entre los niveles de interleuquinas y la presencia de trastornos intraventriculares de la conducción en pacientes con serología positiva para enfermedad de Chagas y fracción de eyección ventricular izquierda conservada. Material y métodos: Se evaluó a 22 pacientes con edades comprendidas entre 21 y 80 años, seropositivos para enfermedad de Chagas, de más de 20 años de evolución y fracción de eyección ventricular izquierda mayor del 50%. Se analizó, además, un grupo control de 14 individuos sanos. Se determinaron las concentraciones en plasma de IFN-γ, IL-1β, IL-6, IL-10, IL-12 (p70), IL-15, IL-17A, MCP-1/CCL2, MIP-1 a/CCL3, TNF-a e IL-2. Se consideró trastornos intraventriculares de la conducción a la presencia de bloqueo de rama derecha, hemibloqueo anterior izquierdo o bloqueo de rama izquierda. Resultados: De los 22 pacientes con serología positiva para enfermedad de Chagas, 10 presentaron trastornos de la intraventriculares de la conducción (45,4%). En el grupo con trastornos intraventriculares de la conducción, se observaron niveles elevados de interleuquinas de alto efecto inflamatorio como INF-γ, IL-15, IL-2 (p70), IL-12, MP1-a, en comparación al grupo control, además de presentar altos valores de IL-10 como mecanismo modulador de una respuesta inmunitaria excesiva. Conclusiones: La asociación entre niveles elevados de interleuquinas y la presencia de trastornos intraventriculares de la conducción plantea un posible proceso inflamatorio crónico para su desarrollo en pacientes chagásicos con fracción de eyección ventricular izquierda conservada.

ABSTRACT Background: Intraventricular conduction disturbances are common in patients with Chagas disease and preserved left ventricular ejection fraction, but their association with higher inflammatory activity is unknown. Objectives: The aim of this study was to determine the presence of an association between interleukin levels and intraventricular conduction disturbances in patients with positive serology for Chagas disease and preserved left ventricular function. Methods: Twenty-two patients between 22 and 80 years of age with positive serology test for Chagas disease with more than 20 years progression and left ventricular ejection fraction ≥50% were included in the study and compared with a control group of 14 healthy individuals. Plasma levels of IFN-γ, IL-1β, IL-6, IL-10, IL-12 (p70), IL-15, IL-17A, MCP-1/CCL2, MIP-1 a/CCL3, TNF-a and IL-2 were measured in patients and controls. Right bundle branch block, left anterior hemiblock or left bundle branch block were considered intraventricular conduction disturbances. Results: Among the 22 patients with positive serology for Chagas disease, 10 presented intraventricular conduction disturbances (45.4%). This group had elevated levels of interleukins with high inflammatory effect such as INF-γ, IL-15, IL-2, IL-12, MIP-1 a, compared with the control group, and high levels of IL-10 as a regulatory mechanism of an excessive immune response. Conclusions: The association between elevated levels of inflammatory interleukins and intraventricular conduction disturbances suggests that chronic inflammation may play a role in the development of these abnormalities in patients with positive serology for Chagas disease and preserved left ventricular ejection function.

Syncope in Patients with Cardiac Pacemakers.

INTRODUCTION: It is challenging to diagnose syncope in patients with pacemakers. Because these patients have increased morbidity and mortality risks, they require immediate attention to determine the causes in order to provide appropriate treatment. This study aimed to investigate the causes and predictive factors of syncope as well as the methods used to diagnose syncope in cardiac pacemaker patients. METHODS: Patients with pacemakers implanted owing to sinus node disease or atrioventricular block were evaluated with standardized questionnaires, endocavitary electrograms, and other tests based on the suspected causes of syncope. Mann- Whitney U tests were used to analyze continuous variables and Chi-squared or Fisher's exact tests were used for categorical variables. Logistic regression was used for multivariate analyses. Statistical significance was P<0.05. RESULTS: The study included 95 patients with pacemakers: 47 experienced syncope in the last 12 months and 48 did not. Of the 100 documented episodes of syncope, 48.9% were vasovagal syncopes, 17% had cardiac-related causes, 10.6% had unknown causes, and 8.5% had pacemaker failure. The multivariate analysis showed that a New York Heart Association (NYHA) Functional Class II was a significant factor for developing syncope (P<0.01). CONCLUSION: While the most common type of syncope in pacemaker patients was neurally mediated, it is important to perform detailed evaluations in this population as the causes of syncope can be life-threatening. The best diagnostic methods were stored electrogram analysis and the tilt table test. NYHA Functional Class II patients were found to have a higher risk for syncope.

Syncope in patients with cardiac pacemakers

Abstract Introduction: It is challenging to diagnose syncope in patients with pacemakers. Because these patients have increased morbidity and mortality risks, they require immediate attention to determine the causes in order to provide appropriate treatment. This study aimed to investigate the causes and predictive factors of syncope as well as the methods used to diagnose syncope in cardiac pacemaker patients. Methods: Patients with pacemakers implanted owing to sinus node disease or atrioventricular block were evaluated with standardized questionnaires, endocavitary electrograms, and other tests based on the suspected causes of syncope. Mann-Whitney U tests were used to analyze continuous variables and Chi-squared or Fisher's exact tests were used for categorical variables. Logistic regression was used for multivariate analyses. Statistical significance was P<0.05. Results: The study included 95 patients with pacemakers: 47 experienced syncope in the last 12 months and 48 did not. Of the 100 documented episodes of syncope, 48.9% were vasovagal syncopes, 17% had cardiac-related causes, 10.6% had unknown causes, and 8.5% had pacemaker failure. The multivariate analysis showed that a New York Heart Association (NYHA) Functional Class II was a significant factor for developing syncope (P<0.01). Conclusion: While the most common type of syncope in pacemaker patients was neurally mediated, it is important to perform detailed evaluations in this population as the causes of syncope can be life-threatening. The best diagnostic methods were stored electrogram analysis and the tilt table test. NYHA Functional Class II patients were found to have a higher risk for syncope.

Three-dimensional visualization of the bovine cardiac conduction system and surrounding structures compared to the arrangements in the human heart.

In the human heart, the atrioventricular node is located toward the apex of the triangle of Koch, which is also at the apex of the inferior pyramidal space. It is adjacent to the atrioventricular portion of the membranous septum, through which it penetrates to become the atrioventricular bundle. Subsequent to its penetration, the conduction axis is located on the crest of the ventricular septum, sandwiched between the muscular septum and ventricular component of the membranous septum, where it gives rise to the ramifications of the left bundle branch. In contrast, the bovine conduction axis has a long non-branching component, which penetrates into a thick muscular atrioventricular septum having skirted the main cardiac bone and the rightward half of the non-coronary sinus of the aortic root. It commonly gives rise to both right and left bundle branches within the muscular ventricular septum. Unlike the situation in man, the left bundle branch is long and thin before it branches into its fascicles. These differences from the human heart, however, have yet to be shown in three-dimensions relative to the surrounding structures. We have now achieved this goal by injecting contrast material into the insulating sheaths that surround the conduction network, evaluating the results by subsequent computed tomography. The fibrous atrioventricular membranous septum of the human heart is replaced in the ox by the main cardiac bone and the muscular atrioventricular septum. The apex of the inferior pyramidal space, which in the bovine, as in the human, is related to the atrioventricular node, is placed inferiorly relative to the left ventricular outflow tract. The bovine atrioventricular conduction axis, therefore, originates from a node itself located inferiorly compared to the human arrangement. The axis must then skirt the non-coronary sinus of the aortic root prior to penetrating the thicker muscular ventricular septum, thus accounting for its long non-branching course. We envisage that our findings will further enhance comparative anatomical research.

Clinical Spectrum of SCN5A Channelopathy in Children with Primary Electrical Disease and Structurally Normal Hearts.

Sodium voltage-gated channel α subunit 5 (SCN5A)-mutations may cause an array of arrhythmogenic syndromes most frequently as an autosomal dominant trait, with incomplete penetrance, variable expressivity and male predominance. In the present study, we retrospectively describe a group of Mexican patients with SCN5A-disease causing variants in whom the onset of symptoms occurred in the pediatric age range. The study included 17 patients with clinical diagnosis of primary electrical disease, at least one SCN5A pathogenic or likely pathogenic mutation and age of onset <18 years, and all available first- and second-degree relatives. Fifteen patients (88.2%) were male, and sixteen independent variants were found (twelve missense, three truncating and one complex inframe deletion/insertion). The frequency of compound heterozygosity was remarkably high (3/17, 17.6%), with early childhood onset and severe disease. Overall, 70.6% of pediatric patients presented with overlap syndrome, 11.8% with isolated sick sinus syndrome, 11.8% with isolated Brugada syndrome (BrS) and 5.9% with isolated type 3 long QT syndrome (LQTS). A total of 24/45 SCN5A mutation carriers were affected (overall penetrance 53.3%), and penetrance was higher in males (63.3%, 19 affected/30 mutation carriers) than in females (33.3%, 5 affected/15 carriers). In conclusion, pediatric patients with SCNA-disease causing variants presented mainly as overlap syndrome, with predominant loss-of-function phenotypes of sick sinus syndrome (SSS), progressive cardiac conduction disease (PCCD) and ventricular arrhythmias.

Conduction Disorders: The Value of Surface ECG.

PURPOSE OF REVIEW: The purpose of the current mini-review is to describe the importance of surface ECG for the diagnosis of conduction disorder. METHODS: The MEDLINE/PubMed database was used, with the keywords "ECG" and "conduction disorders"; over the past 10 years. Other documents were included because of their relevance. MAIN FINDINGS: Data on the anatomy and function of the cardiac electrical system have been described. Conduction disorders including sinus node dysfunction, atrioventricular blocks, intraventricular conduction disorders are exposed as to their epidemiology, etiology, presentation, anatomical site of impaired conduction of the electrical stimulus. The importance of ECG in patients with a cardiac implantable electronic device was also discussed, in addition to future perspectives. CONCLUSION: Surface ECG allows the diagnosis of atrioventricular and intraventricular conduction disorder and its anatomical block site most of the time, without the need for invasive tests such as electrophysiological study. Dysfunctions of cardiac implantable electronic devices can be diagnosed by ECG, as well as the prediction of response to cardiac resynchronization therapy.

Bloqueo de rama alternante: reporte de una complicación inusual tras implante valvular aórtico transcatéter / Alternating bundle branch block: report of an unusual complication after transcatheter aortic valve implantation

Resumen Los trastornos de la conducción representan una potencial complicación de los reemplazos valvulares percutáneos. Los bloqueos alternantes de rama, aunque son inusuales, reflejan daño extenso del sistema His Purkinje con riesgo potencial de bloqueo auriculoventricular completo, por lo cual es importante su identificación y abordaje oportuno. Se presenta el caso de una paciente femenina de 82 años con múltiples comorbilidades y estenosis aórtica severa, en seguimiento médico desde hacía un año, en quien no se había realizado reemplazo quirúrgico por negativa de la paciente y por el alto riesgo intraoperatorio. Ingresó a la institución con un cuadro clínico de disnea progresiva de un mes de evolución, se realizó ecocardiograma transtorácico documentando estenosis aórtica crítica y fue llevada a implante valvular aórtico percutáneo. Por el alto riesgo de necesidad de marcapasos peri o postprocedimiento, se realizó seguimiento con monitoreo Holter, documentando bloqueo alternante de rama, el cual no progresó a bloqueo auriculoventricular completo luego de 72 horas de seguimiento, por lo que no se implantó marcapasos permanente. MÉD.UIS.2020;33(3): 37-42

Abstract Conduction disorders represent a potential complication of percutaneous valve replacements. Alternating bundle branch block, although unusual, reflect extensive damage of the His-Purkinje system with potential risk of complete atrioventricular block, therefore, its identification and timely approach is important. We present the case of an 82 years old female patient with multiple comorbidities and a medical history of severe aortic stenosis in medical follow-up for a year, in whom surgical replacement had not been conducted due to the patient's refusal and to the high surgical risk. She was admitted to the institution referring one month of progressive shortness of breath and an echocardiogram documented critical aortic stenosis. Percutaneous aortic valve implantation was performed. Due to her high risk of needing a peri or post-procedure pacemaker, Holter monitoring was performed, documenting alternating bundle branch block, which did not progress to complete atrioventricular block after 72 hours of follow-up, in consequence, a permanent pacemaker was not implanted. MÉD.UIS.2020;33(3): 37-42

Electrical stimulation applied during differentiation drives the hiPSC-CMs towards a mature cardiac conduction-like cells.

Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) resemble fetal cardiomyocytes and electrical stimulation (ES) has been explored to mature the differentiated cells. Here, we hypothesize that ES applied at the beginning of the differentiation process, triggers both differentiation of the hiPSC-CMs into a specialized conduction system (CS) phenotype and cell maturation. We applied ES for 15 days starting on day 0 of the differentiation process and found an increased expression of transcription factors and proteins associated with the development and function of CS including Irx3, Nkx2.5 and contactin 2, Hcn4 and Scn5a, respectively. We also found activation of intercalated disc proteins (Nrap and ß-catenin). We detected ES-induced CM maturation as indicated by increased Tnni1 and Tnni3 expression. Confocal micrographs showed a shift towards expression of the gap junction protein connexin 40 in ES hiPSC-CM compared to the more dominant expression of connexin 43 in controls. Finally, analysis of functional parameters revealed that ES hiPSC-CMs exhibited faster action potential (AP) depolarization, longer intracellular Ca2+ transients, and slower AP duration at 90% of repolarization, resembling fast conducting fibers. Altogether, we provided evidence that ES during the differentiation of hiPSC to cardiomyocytes lead to development of cardiac conduction-like cells with more mature cytoarchitecture. Thus, hiPSC-CMs exposed to ES during differentiation can be instrumental to develop CS cells for cardiac disease modelling, screening individual drugs on a precison medicine type platform and support the development of novel therapeutics for arrhythmias.

Anatomopathological changes in canine distemper seropositive dogs and virus detection in sinoatrial nodes / Alterações anatomopatológicas em cães soropositivos para cinomose e detecção de vírus em nódulos sinoatriais

Canine distemper is a viral disease that affects several systems on dogs, among them, the cardiovascular system. The aim of this study was to identify canine distemper virus (CDV) in the sinoatrial node (SAN) of dogs serologically positive for distemper by Polymerase Chain Reaction preceded by reverse transcription (RT-PCR), and to analyze gross and microscopic changes of distemper in the heart and other tissues. SAN and tissue fragments were collected from 17 serologically positive dead animals, necropsied from October 2015 to December 2016. In the heart, right heart dilatation was observed in 13 dogs (76.47%) and left concentric hypertrophy in two dogs (11.76%). Microscopically, lymphocytic myocarditis was observed in four (23.53%) dogs and 41.18% presented viral inclusion corpuscles of CDV in the bladder epithelium. Only one (5.88%) dog presented a 319 bp target fragment for distemper virus using primers CDV 1 and CDV 2 at the sinoatrial node. In conclusion, CDV can be located in the sinoatrial node of naturally infected dogs, as demonstrated in this study by the RT-PCR technique, reinforcing the hypothesis that CDV is capable of causing inflammatory lesions in the sinoatrial node of this species. Macroscopic and microscopic cardiac changes are frequently observed in dogs with distemper, mainly cardiac dilatation and myocarditis. Viral inclusions of CDV in bladder epithelial cells are an important microscopic finding for the diagnosis of distemper.

A cinomose canina é uma doença viral que afeta vários sistemas, dentre eles o cardiovascular. Objetivou-se identificar o vírus da cinomose canina no nó sinoatrial (NSA) de cães sorologicamente positivos para cinomose, através da reação em cadeia da polimerase, precedida de transcrição reversa (RT-PCR), além de analisar os achados macroscópicos e histológicos da cinomose no coração e outros tecidos. Foram coletados fragmentos de tecidos e do NSA de 17 cães sorologicamente positivos para cinomose que vieram a óbito e foram necropsiados no período de outubro de 2015 a dezembro de 2016. No coração observou-se dilatação cardíaca direita em 76,47% dos cães e hipertrofia concêntrica esquerda em 11,76% dos cães. Microscopicamente observou-se miocardite linfocítica em 23,53% dos cães e 41,18% apresentou corpúsculos de inclusão viral no epitélio vesical. Somente um (5,88%) cão apresentou fragmento alvo de 319 bp para cinomose utilizando os primers VCC1 e VCC2, no nó sinoatrial. Conclui-se que o VCC pode localizar-se no nó sinoatrial de cães naturalmente infectados, como demonstrados neste estudo pela técnica de RT-PCR, reforçando a hipótese de que o VCC é capaz de provocar lesões inflamatórias no nó sinoatrial dessa espécie. Alterações cardíacas macroscópicas e microscópicas, principalmente dilatação cardíaca e miocardite, são frequentemente observadas em cães com cinomose. Inclusões virais nas células epiteliais da bexiga são importantes achados microscópicos para diagnóstico da cinomose.

Why do we break one of the first rules of anatomy when describing the components of the heart?

A rule of human anatomy is that all structures within the body should be described relative to the so-called "anatomical position." Along with those describing structures such as the skull and liver, those accounting for the components of the heart consistently break this rule, describing the organ as if removed from the body and positioned on its apex, the so-called "Valentine position." Although potentially appropriate to some animal species, this approach produces problems when used in human anatomy, even if the right and left ventricles are only viewed in truly right-sided and left-sided positions when assessed in the Valentine fashion. The names of the ventricles, of course, are never going to change. This is not necessarily the case with other cardiac components. Consider the artery that extends between the ventricles on their diaphragmatic surface. Blockage produces inferior myocardial infarction, which is to be expected, since the vessel is located in inferior and interventricular position. It is incorrect to describe the artery as being posterior and descending. Such infelicities are now the more obvious with the advent of techniques that, in clinical cardiology, show the components of the heart as it lies within the chest. In this review, we have assessed the frequency of use of the Valentine approach in popular textbooks used by students of human anatomy. We show that, using the conduction tissues as a model, this system also being incorrectly described in the majority of the textbooks, the situation can be improved by use of attitudinally appropriate description. Clin. Anat. 32:585-596, 2019. © 2019 Wiley Periodicals, Inc.

Assessment of Subclinical Cardiac Alterations and Atrial Electromechanical Delay by Tissue Doppler Echocardiography in Patients with Nonfunctioning Adrenal Incidentaloma / Avaliação de Alterações Cardíacas Subclínicas e Atraso Eletromecânico Atrial por Ecocardiografia com Doppler Tecidual em Pacientes com Incidentaloma Adrenal Não Funcionante

Abstract Background: Majority of the incidentally discovered adrenal masses, called adrenal incidentaloma (AI), are nonfunctioning adrenal adenomas. The appropriate management of AI is still a matter debate, so it is necessary to investigate their associated morbidity. However, data regarding morphological and functional cardiac alterations are limited in this group. Objective: In this study, we aimed to assess cardiac structural and functional characteristics and atrial conduction properties in patients with nonfunctioning AI. Methods: Thirty patients with nonfunctioning AI and 46 properly matched control subjects were included in the study. After hormonal and biochemical analysis, all participants underwent transthoracic echocardiography to obtain systolic and diastolic parameters of both ventricles, in addition to atrial conduction times by tissue Doppler echocardiography. Data were analyzed with Statistical Package for the Social Sciences (SPSS, Chicago, IL, United States) statistics, version 17.0 for Windows. P < 0.05 was considered statistically significant. Results: Left ventricular (LV) mass index and LV myocardial performance index were significantly increased in AI group. Among atrial conduction times, both intra- and interatrial electromechanical delays were significantly prolonged in patients with nonfunctioning AI. Other laboratory and echocardiographic findings were similar between groups. Conclusion: Our study revealed that intra- and inter-atrial conduction times were prolonged, and LV mass index was increased in patients with nonfunctioning AI. These findings may be markers of subclinical cardiac involvement and tendency to cardiovascular complications. Close follow-up is necessary for individuals with nonfunctioning AI for their increased cardiovascular risk.

Resumo Fundamento: A maioria das massas adrenais descobertas incidentalmente, denominadas incidentaloma adrenal (IA), são adenomas adrenais não funcionantes. O manejo adequado da IA ainda é um tema de debate, e por isso é necessário investigar suas morbidades associadas. Entretanto, dados referentes a alterações cardíacas morfológicas e funcionais são limitados nesse grupo. Objetivo: Neste estudo, objetivamos avaliar as características estruturais e funcionais cardíacas e as propriedades de condução atrial em pacientes com IA não funcionante. Métodos: Trinta pacientes com IA não funcionante e 46 controles adequadamente pareados foram incluídos no estudo. Após análise hormonal e bioquímica, todos os participantes foram submetidos a ecocardiograma transtorácico para obtenção de parâmetros sistólicos e diastólicos de ambos os ventrículos, além dos tempos de condução atrial pelo ecocardiograma com Doppler tecidual. Os dados foram analisados com o Statistical Package for the Social Sciences (SPSS, Chicago, IL, Estados Unidos), versão 17.0 para Windows. P < 0,05 foi considerado estatisticamente significativo. Resultados: O índice de massa do ventrículo esquerdo (VE) e o índice de desempenho miocárdico do VE foram significativamente aumentados no grupo IA. Entre os tempos de condução atrial, os atrasos eletromecânicos intra- e interatriais foram significativamente prolongados em pacientes com IA não funcionante. Outros achados laboratoriais e ecocardiográficos foram semelhantes entre os grupos. Conclusão: Nosso estudo revelou que os tempos de condução intra- e interatrial estavam prolongados e o índice de massa do VE estava aumentado em pacientes com IA não funcionante. Esses achados podem ser marcadores de envolvimento cardíaco subclínico e de tendência a complicações cardiovasculares. Um acompanhamento rigoroso é necessário para indivíduos com IA não funcionante, devido ao aumento do risco cardiovascular.