Remodelado eléctrico reverso en pacientes tratados con terapia de resincronización cardíaca / Reverse electrical remodeling in patients under cardiac resynchronization therapy

RESUMEN Introducción : La terapia de resincronización cardíaca (TRC) se indica en pacientes que habitualmente presentan remodelado cardíaco generado por dilatación y disincronía contráctil. La TRC contribuye al remodelado reverso, relacionado con menor mortalidad y hospitalizaciones por insuficiencia cardíaca (IC). Se han observado además mejoras en la conducción intraventricular, con reducción del tiempo de activación. La cuantificación del remodelado eléctrico reverso se ha subutilizado como parámetro de respuesta, con escasos reportes sobre su asociación con la respuesta clínica-estructural. Objetivo : Analizar el remodelado eléctrico reverso intraventricular como parámetro de respuesta a la TRC. Métodos: Se incluyeron pacientes con más de 6 meses de implante. Se obtuvo un ECG con estimulación desactivada (QRS intrínseco, QRSi, post TRC), y por ecocardiograma transtorácico se definió la fracción de eyección ventricular izquierda (FEVI), el diámetro de fin de diástole del ventrículo izquierdo (DFDVI) y la presencia de insuficiencia mitral. Se clasificó a los pacientes según la respuesta clínica-estructural. El remodelado eléctrico se caracterizó con la comparación de la duración del QRS pre y post TRC y la valoración de los cambios del QRS (ΔQRSi) entre grupos. Resultados : Se incluyeron 23 pacientes. Un 39% presentó disminución >10 mseg del QRSi. Observamos un QRSi de -9,3 ± 20,7 mseg en respondedores, y 11,25 ± 18,9 mseg en no respondedores (p = 0,027), más acentuada en los hiper respondedores (ΔQRSi: -14,44 ± 17,40 mseg, p = 0,026). Las mujeres con QRS ≥150 mseg pre TRC exhibieron disminución significativa del QRSi (p = 0,0195). Conclusiones : El remodelado eléctrico reverso se comprobó en 39% de los pacientes que recibieron TRC. Observamos una relación significativa del QRSi con la respuesta clínica-estructural, mayor en hiper respondedores. Mujeres con QRS ancho pre-TRC exhiben remodelado eléctrico reverso más acentuado. Este es un parámetro de fácil acceso e interpretación durante los controles ambulatorios.

ABSTRACT Introduction : Cardiac resynchronization therapy (CRT) is indicated in patients who often present cardiac remodeling due to dilatation and contractile dyssynchrony. CRT contributes to reverse remodeling which is associated with reduced mortality and heart failure (HF) hospitalizations. Improvements in intraventricular conduction with decreased ventricular activation time have also been observed. The quantification of reverse electrical remodeling has been underused as a parameter of response, and there are few reports on its association with the clinical-structural response. Objective : To analyze intraventricular reverse electrical remodeling as a parameter of response to CRT in living individuals. Methods : We included patients implanted at least 6 months ago. A deactivated stimulation ECG (post-CRT intrinsic QRS) was obtained, and by means of transthoracic echocardiography (TTE), the left ventricular ejection fraction (LVEF), the left ventricular end-diastolic diameter (LVEDD) and the presence of mitral regurgitation were defined. Patients were classified according to their clinical-structural response. Electrical remodeling was characterized by comparing pre- and post-CRT QRS duration and assessing QRS changes (ΔiQRS) between groups. Results : A total of 23 patients were included, 39% of which showed a >10 ms decrease in iQRS. We observed a iQRS of -9.3±20.7 ms in responders, and of 11.25±18.9 ms in non-responders (p=0.027), more marked in hyper-responders (ΔiQRS: -14.44±17.40 ms, p=0.026). Women with pre-CRT QRS ≥150 ms showed a significant decrease in iQRS (p=0.0195). Conclusion : Reverse electrical remodeling was found in 39% of the patients under CRT. We noted a significant relationship between iQRS and clinical-structural response, higher in hyper-responders. Women with wider pre-CRT QRS showed more marked reverse electrical remodeling. This parameter is accessible and easy to read in outpatient visits.

Viabilidade do Implante de Eletrodo Ventricular Esquerdo na Terapia de Ressincronização Cardíaca Guiada por Gated SPECT e Remodelamento Ventricular / Feasibility of Left Ventricle Lead Implantation in Cardiac Resynchronization Therapy Guided by Gated SPECT and Ventricular Remodeling

Resumo Fundamento A terapia de ressincronização cardíaca (TRC) pode beneficiar pacientes com insuficiência cardíaca (IC) avançada. O índice de excentricidade anormal por gated SPECT está relacionado a alterações estruturais e funcionais do ventrículo esquerdo (VE). Objetivo O objetivo do presente estudo foi avaliar a viabilidade do implante de eletrodos do VE guiado por análise de fase e sua relação com o remodelamento ventricular. Métodos Dezoito pacientes com indicação de TRC foram submetidos à cintilografia miocárdica para orientar o implante, avaliando-se os parâmetros de excentricidade e forma ventricular. P < 0,05 foi adotado como significância estatística. Resultados Na linha de base do estudo, a maioria dos pacientes foi classificada como NYHA 3 (n = 12). Após a TRC, 11 dos 18 pacientes foram reclassificados para um menor grau de limitação funcional. Além disso, a qualidade de vida dos pacientes melhorou após a TRC. Foram observadas reduções significativas na duração do QRS, intervalo PR, índice de forma diastólica final, índice de forma sistólica final, volume sistólico e massa miocárdica pós-TRC. O eletrodo do VE da TRC foi posicionado concordante, adjacente e discordante em 11 (61,1%), 5 (27,8%) e 2 (11,1%) pacientes, respectivamente. A excentricidade sistólica e diastólica final demonstrou remodelamento reverso após a TRC. Conclusões O implante de eletrodo do VE em TRC guiado por cintilografia gated SPECT é viável. A colocação do eletrodo concordante ou adjacente ao último segmento a se contrair foi um determinante do remodelamento reverso.

Abstract Background Cardiac resynchronization therapy (CRT) may benefit patients with advanced heart failure (HF). Abnormal eccentricity index by gated SPECT is related to structural and functional alterations of the left ventricle (LV). Objective The aim of this study is to evaluate the feasibility of LV lead implantation guided by phase analysis and its relationship to ventricular remodeling. Methods Eighteen patients with indication for CRT underwent myocardial scintigraphy for implant orientation, and eccentricity and ventricular shape parameters were evaluated. P < 0.05 was adopted as statistical significance. Results At baseline, most patients were classified as NYHA 3 (n = 12). After CRT, 11 out of 18 patients were reclassified to a lower degree of functional limitation. In addition, patients' quality of life was improved post-CRT. Significant reductions were observed in QRS duration, PR interval, end-diastolic shape index, end-systolic shape index, stroke volume, and myocardial mass post-CRT. The CRT LV lead was positioned concordant, adjacent, and discordant in 11 (61.1%), 5 (27.8%), and 2 (11.1%) patients, respectively. End-systolic and end-diastolic eccentricity demonstrated reverse remodeling post-CRT. Conclusions LV lead implantation in CRT guided by gated SPECT scintigraphy is feasible. The placement of the electrode concordant or adjacent to the last segment to contract was a determinant of reverse remodeling.

Estratégias Percutâneas em Doenças Estruturais: Foco em Insuficiência Cardíaca Crônica / Percutaneous Strategies in Structural Heart Diseases: Focus on Chronic Heart Failure

Resumo As inovações em dispositivos ao longo das últimas décadas proporcionaram uma melhora no diagnóstico e tratamento de pacientes com insuficiência cardíaca. Essas novas ferramentas progressivamente adaptaram-se a estratégias minimamente invasivas e as opções percutâneas multiplicaram-se de forma rápida. No presente artigo revisamos as direções atuais e futuras dos dispositivos utilizados como opções adjuvantes para o diagnóstico e tratamento adjuvante na insuficiência cardíaca crônica, o seu desenvolvimento, mecanismos e estudos mais recentes

Abstract Innovations in devices during the last decade contributed to enhanced diagnosis and treatment of patients with cardiac insufficiency. These tools progressively adapted to minimally invasive strategies with rapid, widespread use. The present article focuses on actual and future directions of device-related diagnosis and treatment of chronic heart failure.

Effects of Cardiac Resynchronization Therapy on a Six-minute Walk Test, Maximal Inspiratory Pressure and Peak Expiratory Flow in Patients with Heart Failure: A Longitudinal Study

Abstract Background: Cardiac resynchronization therapy (CRT) is an effective treatment for patients with heart failure. Objective: To evaluate the response of CRT in maximal inspiratory pressure (MIP), peak expiratory flow (PEF), and exercise tolerance as determined by the six-minute walk test (6MWT) in patients with HF. Methods: This study used the 6MWT and Manovacuometer to assess functional capacity in relation to activities of daily living, in which fatigue and dyspnea are common. Results: After six months of CRT, this study identified improvements in the 6MWT, p<0.05; MIP, p=0.01; and PEF, p=0.03. Conclusion: After CRT, this study showed a significant improvement in MIP, PEF, and exercise tolerance. However, further studies are warranted to demonstrate the relevance of these findings.

Capacidade Preditiva dos Parâmetros do Teste de Esforço Cardiopulmonar em Pacientes com Insuficiência Cardíaca em Terapia de Ressincronização Cardíaca / Predictive Ability of Cardiopulmonary Exercise Test Parameters in Heart Failure Patients with Cardiac Resynchronization Therapy

Resumo Fundamento Há evidências sugerindo que um corte do pico de consumo de oxigênio (pVO2) de 10ml/kg/min fornece uma estratificação de risco mais precisa em pacientes com Terapia de Ressincronização Cardíaca (TRC). Objetivo Comparar o poder prognóstico de vários parâmetros do teste cardiopulmonar de exercício (TCPE) nesta população e avaliar a capacidade discriminativa dos valores de corte de pVO2 recomendados pelas diretrizes. Métodos Avaliação prospectiva de uma série consecutiva de pacientes com insuficiência cardíaca (IC) com fração de ejeção do ventrículo esquerdo ≤40%. O desfecho primário foi um composto de morte cardíaca e transplante cardíaco urgente (TC) nos primeiros 24 meses de acompanhamento, e foi analisado por vários parâmetros do TCPE para a maior área sob a curva (AUC) no grupo TRC. Uma análise de sobrevida foi realizada para avaliar a estratificação de risco fornecida por vários pontos de corte diferentes. Valores de p < 0,05 foram considerados significativos. Resultados Um total de 450 pacientes com IC, dos quais 114 possuíam aparelho de TRC. Esses pacientes apresentaram um perfil de risco basal mais alto, mas não houve diferença em relação ao desfecho primário (13,2% vs 11,6%, p = 0,660). A pressão expiratória de dióxido de carbono no limiar anaeróbico (PETCO2AT) teve o maior valor de AUC, que foi significativamente maior do que o de pVO2 no grupo TRC (0,951 vs 0,778, p = 0,046). O valor de corte de pVO2 atualmente recomendado forneceu uma estratificação de risco precisa nesse cenário (p <0,001), e o valor de corte sugerido de 10 ml/min/kg não melhorou a discriminação de risco em pacientes com dispositivos (p = 0,772). Conclusão A PETCO2AT pode superar o poder prognóstico do pVO2 para eventos adversos em pacientes com TRC. O ponto de corte de pVO2 recomendado pelas diretrizes atuais pode estratificar precisamente o risco dessa população.

Abstract Background There is evidence suggesting that a peak oxygen uptake (pVO2) cut-off of 10ml/kg/min provides a more precise risk stratification in cardiac resynchronization therapy (CRT) patients. Objective To compare the prognostic power of several cardiopulmonary exercise testing (CPET) parameters in this population and assess the discriminative ability of the guideline-recommended pVO2cut-off values. Methods Prospective evaluation of consecutive heart failure (HF) patients with left ventricular ejection fraction ≤40%. The primary endpoint was a composite of cardiac death and urgent heart transplantation (HT) in the first 24 follow-up months, and was analysed by several CPET parameters for the highest area under the curve (AUC) in the CRT group. A survival analysis was performed to evaluate the risk stratification provided by several different cut-offs. p values <0.05 were considered significant. Results A total of 450 HF patients, of which 114 had a CRT device. These patients had a higher baseline risk profile, but there was no difference regarding the primary outcome (13.2% vs 11.6%, p =0.660). End-tidal carbon dioxide pressure at anaerobic threshold (PETCO2AT)had the highest AUC value, which was significantly higher than that of pVO2in the CRT group (0.951 vs 0.778, p =0.046). The currently recommended pVO2cut-off provided accurate risk stratification in this setting (p <0.001), and the suggested cut-off value of 10 ml/min/kg did not improve risk discrimination in device patients (p =0.772). Conclusion PETCO2ATmay outperform pVO2's prognostic power for adverse events in CRT patients. The current guideline-recommended pVO2 cut-off can precisely risk-stratify this population.

Implante de un electrodo de estimulación ventricular izquierdo mediante doble canulación del seno coronario, técnica de snare y acceso retrógrado de la vena posterolateral / Implant of a left ventricular pacing electrode by double cannulation of the coronary sinus, snare technique and retrograde access of the posterolateral vein

Resumen El implante percutáneo de un electrodo de estimulación ventricular izquierdo a través del seno coronario para resincronización cardiaca siempre ha implicado un reto y más aún en pacientes con anatomía venosa coronaria compleja. Este caso demuestra cómo una técnica de doble canulación del seno coronario con uso de catéter multi-snare permite la colocación exitosa de un electrodo de estimulación ventricular izquierdo mediante acceso retrógrado a una vena posterolateral estenótica.

Abstract The percutaneous implantation of a left ventricular pacing electrode through the coronary sinus for cardiac resynchronization has always been a challenge, especially in patients with a complex coronary venous anatomy. This case shows how double cannulation of the coronary sinus using a multisnare catheter allows a left ventricular pacing electrode to be placed through retrograde access to a stenotic posterolateral vein, with a good clinical outcome.

Terapia de resincronización cardíaca. Incidencia y mecanismos involucrados en la reducción de la insuficiencia mitral funcional / Cardiac Resynchronization Therapy. Incidence and Mechanisms Involved in the Reduction of Functional Mitral Regurgitation

RESUMEN Introducción: La insuficiencia mitral funcional (IMF) es común en pacientes con insuficiencia cardíaca (IC). La IMF moderada/ grave (M/G) se asocia a peor pronóstico. Objetivo: Describir la prevalencia de IMF y los mecanismos involucrados en su reducción en respondedores a la terapia de resincronización cardíaca (TRC) a los 6 meses comparados con 12 y 24 meses. Métodos: Entre 2009 y 2018 fueron tratados 338 pts. Respondedores: reducción de CF NYHA ≥1 grado o aumento de la fracción de eyección ventricular izquierda (FEVI) ≥5% (absoluto). La IMF se graduó en 4 puntos: No-IMF, leve, M y G, y se la relacionó con las mediciones ecocardiográficas. Características Basales: edad 64 ±10 años, hombres 71%, CF-NYHA IIIII 92%, bloqueo de rama izquierda (BRI) 67%, QRS ≥150 ms 75%, diámetro diastólico del VI (DDVI) 68 ± 9 mm, diámetro sistólico del VI (DSVI) 52 ± 12 mm, FEVI 24 ± 7%. Resultados: La prevalencia de IMF fue del 92,6%. A los 6 meses, 86% fueron respondedores y 23% de ellos mejoraron de IMF-M/G a IMF-Leve/No-IMF. Hubo un fuerte remodelado inverso: DDVI 68 ± 10 vs 63 ± 11 mm, (p = 0,0001), DSVI 55 ± 12 vs 50 ± 13 mm, (p = 0,0006) y FEVI 25 ± 11 vs 33 ± 10%, (p = 0,00001). Comparando 6 con 12 meses 89,4% fueron respondedores, 8% mejoraron de IMF-M/G a IMF-Leve/No-IMF. Comparando 6 con 24 meses 88% fueron respondedores, 14,6% mejoraron de IMF-M/G a IMF-Leve/No-IMF. Entre 6 y 12 y 6 y 24 meses no hubo remodelado inverso significativo. Conclusiones: La prevalencia de IMF fue elevada. El mayor remodelado inverso y reducción de la IMF se observaron a los 6 meses, siendo el primero el principal mecanismo en la reducción de la IMF. Esta mejoría se sostuvo a los 12 y 24 meses.

ABSTRACT Background: Functional mitral regurgitation (FMR) is common in heart failure, and moderate/severe (M/S) FMR is associated with worse prognosis. Objective: The aim of this study was to describe the prevalence of FMR and the mechanisms involved in its reduction in responders to cardiac resynchronization therapy (CRT) at 6 months compared with 12 and 24 months. Methods: Between 2009 and 2018, 338 patients received CRT. Patients showing NYHA functional class (FC) reduction ≥1 or left ventricular ejection fraction (LVEF) absolute increase ≥5% were considered responders. Functional mitral regurgitation was graded using a 4-point scale into none-, mild-, M- and S-FMR, and was related to echocardiographic measurements. Baseline patient characteristics were: age 64±10 years, men 71%, NYHA FC II-III 92%, left bundle branch block (LBBB) 67%, QRS ≥150 ms 75%, LV diastolic diameter (LVDD) 68±9 mm, LV systolic diameter (LVSD) 52±12 mm, and LVEF 24±7%. Results: The prevalence of FMR was 92.6%. At 6 months, 86% were responders, 23% improved from M/S-FMR to mild/none-FMR and there was strong reverse remodeling: LVDD 68±10 vs. 63±11 mm, (p=0.0001), LVSD 55±12 vs. 50±13 mm, (p=0.0006) and LVEF 25±11 vs. 33±10%, (p=0.00001). Comparing 6 with 12 months, 89.4% were responders and 8% improved M/S-FMR to mild/none-FMR. Comparing 6 with 24 months, 88% were responders and 14.6% improved M/S-FMR to mild/none-FMR. Between 6 and 12 and 6 and 24 months, there was no significant reverse remodeling. Conclusions: The prevalence of FMR was high. The highest reverse remodeling and FMR reduction was observed at 6 months, the former being the main mechanism of FMR reduction. This improvement persisted at 12 and 24 months.

Guía atrapada durante cambio de electrodo del seno coronario en terapia de resincronización cardiaca / Trapped guidewire during coronary sinus electrode exchange in cardiac resynchronization therapy

Resumen Se presenta el caso de una paciente con atrapamiento de guía al interior del seno coronario durante el procedimiento de cambio de un electrodo (Sentus ProMRI OTW BP L-85) por desalojo asociado a disfunción de la terapia de resincronización cardiaca. Durante el implante del nuevo electrodo se presentó atrapamiento y retención intravascular de la guía utilizada para su posicionamiento a nivel del seno coronario, lo cual hizo imposible su remoción. La paciente no aceptó tratamiento quirúrgico, se encuentra en vigilancia médica y permanece asintomática desde hace 3 años.

Abstract It is reported the case of a patient with guidewire trapping inside the coronary sinus during an electrode exchange procedure (Sentus ProMRI OTW BP L-85) due to dislocation associated with dysfunction of cardiac re-synchronization therapy. During the implantation of the new electrode, entrapment of the guidewire used for its positioning at the level of the coronary sinus and intravascular retention were presented, making it impossible to remove it. The patient did not accept surgical treatment and has been under medical surveillance, asymptomatic for three years.

Patient with an implantable cardiac electrical stimulation device. What should the anesthesiologist know? / Paciente con dispositivo de estimulación eléctrica cardiaca implantable. ¿Qué debe saber el anestesiólogo?

Abstract Patients with implantable electric stimulation devices are challenging to the anesthesiologist since these cases demand a comprehensive knowledge about how the device operates, the indications for the implant and the implications that must be addressed during the perioperative period. This article is intended to provide the reader with clear and structured information so that the anesthesiologist will be able to safely deal with the situation of a patient with an implantable cardiac stimulation device, who has been programmed for emergent surgery. A search for the scientific evidence available was conducted in Pubmed / Medline, ScienceDirect, OVID, SciELO), for a non-systematic review. The incidence of the use of cardiac electric stimulation devices has been growing. Their operation is increasingly complex, and demands being constantly updated on the knowledge in the area.

Resumen El paciente portador de un dispositivo de estimulación eléctrica cardiaca implantable se convierte en un reto para el anestesiólogo debido a que implica un conocimiento integral que abarca su funcionamiento, las indicaciones que llevaron a su implante y las implicaciones que se deben abordar en el perioperatorio. Este artículo busca proporcionar al lector información clara y estructurada que le permita al anestesiólogo enfrentarse de forma segura al escenario de un paciente con un dispositivo de estimulación eléctrica cardiaca implantable programado para cirugía emergente. Se realizó una búsqueda de la evidencia científica disponible en bases de datos (Pubmed / Medline, ScienceDirect, OVID, SciELO), para una revisión no sistemática. La incidencia en el uso de dispositivos de estimulación eléctrica cardiaca viene en aumento. Su funcionamiento es cada vez más complejo lo cual implica una actualización permanente del conocimiento en esta área.

Remoção Percutânea de Eletrodos de Estimulação Cardíaca Artificial em um Único Centro Sul-Americano / Percutaneous Removal of Cardiac Leads in a Single Center in South America

Resumo Fundamento: Nas últimas décadas, o número de dispositivos eletrônicos cardíacos implantáveis (DCEI) aumentou consideravelmente, assim como a necessidade de remoção destes. Neste contexto, a remoção percutânea apresenta-se como uma técnica segura e capaz de evitar uma cirurgia cardíaca convencional. Objetivos: Primário: descrever a taxa de sucesso e complicações da remoção percutânea de DCEI em um hospital público brasileiro. Secundário: estabelecer preditores de sucesso e complicações. Métodos: Serie de casos retrospectiva de todos os pacientes submetidos à remoção de DCEI em um hospital público brasileiro no período de janeiro de 2013 a junho de 2018. Remoção, explante e extração de eletrodos, complicações e desfechos foram definidos conforme a diretriz norte-americana de 2017. Variáveis categóricas foram comparadas pelos testes Qui-quadrado ou Fisher, enquanto variáveis contínuas, por testes não pareados. O nível de significância adotado nas análises estatísticas foi de 5%. Resultados: 61 pacientes foram submetidos à remoção de DCEI, sendo 51 extrações e 10 explantes. No total, 128 eletrodos foram removidos. Taxa de sucesso clínico foi 100% no grupo do explante e 90,2% no da extração (p=0,58). Complicações maiores foram encontradas em 6,6% dos pacientes. Falha do procedimento foi associada a eletrodos de ventrículo (p=0,05) e átrio (p=0,04) direito implantados há mais tempo. Duração do procedimento (p=0,003) e necessidade de transfusão sanguínea (p<0,001) foram associadas a maior índice de complicação. Conclusão: As taxas de complicação e sucesso clínico observadas foram de 11,5% e 91,8%, respectivamente. Remoções de eletrodos atriais e ventriculares mais antigos estiveram associados a menores taxa de sucesso. Procedimentos mais longos e necessidade de transfusão sanguínea foram associados a complicações.

Abstract Background: In the last decade, the number of cardiac electronic devices has risen considerably and consequently the occasional need for their removal. Concurrently, the transvenous lead removal became a safe procedure that could prevent open-heart surgery. Objective: The primary objective of this study was to describe the successful performance and the complication rates of pacemaker removals in a Brazilian public hospital. Our secondary aim was to describe the variables associated to successes and complications. Methods: A retrospective case series was conducted in patients submitted to pacemaker removal in a Brazilian public hospital from January 2013 to June 2018. Removal, explant, extraction, success and complication rates were defined by the 2017 Heart Rhythm Society Guideline. Categorical variables were compared using x2 or Fisher's tests, while continuous variables were compared by unpaired tests. A p-value of 0.05 was considered statistically significant. Results: Cardiac device removals were performed in 61 patients, of which 51 were submitted to lead extractions and 10 to lead explants. In total, 128 leads were removed. Our clinical success rate was 100% in the explant group and 90.2% in the extraction one (p=0.58). Major complications were observed in 6.6% patients. Procedure failure was associated to older right ventricle (p=0.05) and atrial leads (p=0,04). Procedure duration (p=0.003) and need for blood transfusion (p<0,001) were associated to more complications. Conclusion: Complications and clinical success were observed in 11.5% and 91.8% of the population, respectively. Removal of older atrial and ventricular leads were associated with lower success rates. Longer procedures and blood transfusions were associated with complications.

Manejo de la insuficiencia cardiaca con estimulación hisiana en bloqueo de rama derecha: reporte de caso / Management of heart failure with His bundle pacing in right bundle branch block: case report

Resumen La terapia de resincronización cardiaca mediante estimulación hisiana ha demostrado ser efectiva en pacientes con bloqueo de rama izquierda del haz de His e insuficiencia cardiaca. Paciente masculino, con 47 años de edad, con insuficiencia cardiaca, fracción de expulsión del 17% y miocardio dilatada idiopática, electrocardiograma en ritmo sinusal, bloqueo auriculoventricular de 1.er grado, intervalo PR 400 ms, bloqueo completo de rama derecha del haz de His, bloqueo del fascículo anterior de la rama izquierda del haz de His, duración del QRS 200 ms. Se decidió realizar estimulación selectiva del haz de His. La resincronización cardiaca biventricular convencional en pacientes con presencia de bloqueo completo de la rama derecha del haz de His no está indicada debido a la pobre respuesta al tratamiento. La estimulación hisiana permite reclutar la rama bloqueada y reestablecer la conducción a través de ella, de tal forma que, en ausencia de necrosis, se logre sincronía biventricular. En el caso presentado el reclutamiento de la rama derecha mediante estimulación hisiana se reflejó en el restablecimiento de la sincronía biventricular, medida por rastreo de marcas (speckle tracking) e incremento significativo de la fracción de expulsión del ventrículo izquierdo del 17 al 36.6%, con un incremento absoluto del 19.6%.

Abstract Cardiac resynchronization therapy has proven to be an effective therapy in patients with left bundle branch block and heart failure. Male, 47 years old, heart failure with a left ventricle ejection fraction of 17%, idiopathic heart failure. ECG with sinus rhythm, 1st degree AV block, PR 400 ms, complete right bundle branch block, anterior hemi-fascicle of the left bundle of His, and QRS duration 200 ms. We decided to perform a selective His bundle pacing. In patients with right bundle branch block the biventricular cardiac resynchronization is not indicated due to low treatment response. His bundle pacing allows recruiting the blocked branch and restoring conduction throughout it, therefore, in the absence of necrosis the biventricular synchrony is achieved. We presented a case of His bundle pacing with recruitment of the right bundle branch, which reestablish biventricular synchrony measured by speckle tracking, and with a significant increase of the left ventricle ejection fraction from 17 to 36.6%, with an absolute increase of 19.6%.

Recomendações para o manejo de dispositivos cardíacos eletrônicos implantáveis post mortem / Recommendations for the post-mortem management of cardiac implantable electronic devices

O manejo de dispositivos cardíacos eletrônicos implantáveis de pacientes que evoluem a óbito tem sido motivo de controvérsia. Em nosso meio, não há recomendações uniformes, estando baseadas exclusivamente em protocolos institucionais e em costumes regionais. Quando o cadáver é submetido para cremação, além de outros cuidados, recomenda-se a retirada do dispositivo devido ao risco de explosão e dano do equipamento crematório. Principalmente no contexto da pandemia causada pelo SARS-Cov-2, a orientação e organização de unidades hospitalares e serviços funerários é imprescindível para minimizar o fluxo de pessoas em contato com fluidos corporais de indivíduos falecidos por COVID-19. Nesse sentido, a Sociedade Brasileira de Arritmias Cardíacas elaborou este documento com orientações práticas, tendo como base publicações internacionais e recomendação emitida pelo Conselho Federal de Medicina do Brasil.

The management of cardiac implantable electronic devices after death has become a source of controversy. There are no uniform recommendations for such management in Brazil; practices rely exclusively on institutional protocols and regional custom. When the cadaver is sent for cremation, it is recommended to remove the device due to the risk of explosion and damage to crematorium equipment, in addition to other precautions. Especially in the context of the SARS-CoV-2 pandemic, proper guidance and organization of hospital mortuary facilities and funeral services is essential to minimize the flow of people in contact with bodily fluids from individuals who have died with COVID-19. In this context, the Brazilian Society of Cardiac Arrhythmias has prepared this document with practical guidelines, based on international publications and a recommendation issued by the Brazilian Federal Medical Council.

Complications related to cardiac implantable electronic devices / Complicaciones asociadas al implante de dispositivos cardiacos electrónicos

Abstract Introduction: complications due to cardiac implantable electronic devices have been sparsely studied despite the increased number and complexity of these procedures in a population with multiple comorbidities. Objective: to determine the complication rate and associated risk factors at a reference center in Colombia. Methods: retrospective cohort study, which included patients who had a cardiac electronic device implanted between 2012 and 2015. Clinical records were reviewed to determine if patients developed complications during the year after the procedure, and, if so, which type and which clinical variables could be related to. Results: a total of 897 patients were included, 620 with pacemaker implants and 277 with other devices. The average age was 71.4 years, 63.9% were men, almost all the patients had a chronic disease, and 70% were de novo implants. The global complication rate was 10.9%; Lead displacement (3.6%) and pocket hematoma (3.3%) were the most frequent complications; 7.5% were major complications, and 73.5% occurred in the first month after procedure. The hospitalization rate associated with complications was 9.5%, and the median hospital stay was seven days, with 66.3% of these patients requiring new interventions. The mortality rate was 0.2% Conclusions: complications associated with cardiac implantable electronic devices occur red mainly in the first trimester after the initial intervention, were more frequent in patients under 80 years old, increased according to device complexity, and were not related to with the studied comorbidities.

Resumen Introducción: las complicaciones secundarias al implante de dispositivos cardiacos electrónicos han sido poco estudiadas a pesar del aumento en número y complejidad de estos procedimientos en población con múltiples comorbilidades. Objetivo: determinar la tasa de complicaciones del implante de dispositivos y los factores de riesgo asociados, en un centro de referencia en Colombia. Métodos: estudio de cohorte retrospectiva, que incluyó pacientes a quienes se les implantó dispositivo electrónico cardiaco entre 2012 y 2015. Se revisó la historia clínica para determinar si durante un año posterior al procedimiento, presentaron complicaciones, de qué tipo y con qué variables clínicas podría asociarse. Resultados: se incluyeron 897 pacientes, 620 con implante de marcapaso y 277 otros dispositivos. La edad promedio fue 71.4 años, 63.9% hombres, con múltiples enfermedades crónicas, 70% fueron implantes de novo. Se observó una tasa de complicaciones del 10.9%, la cual varía de acuerdo con el tipo de dispositivo. El desalojo del electrodo (3.6%) y el hematoma del bolsillo (3.3%) fueron las complicaciones más frecuentes, 7.5% fueron complicaciones mayores y 73.5% se presentaron en el primer mes postoperatorio. La tasa de hospitalización asociada a complicación fue 9.5%, mediana de estancia de 7 días, con un 66.3% de los pacientes en requerimiento de reintervención. La tasa de mortalidad fue del 0.2%. Conclusiones: las complicaciones asociadas al implante de dispositivos eléctricos cardiacos se presentaron principalmente en el primer trimestre, fueron más frecuentes en menores de 80 años, aumentaron con la complejidad del dispositivo y no se relacionaron con las comorbilidades estudiadas.

La asincronía ventricular izquierda como resultado de la estimulación apical permanente por dispositivos en el ventrículo derecho / Left ventricular dyssynchrony as result of right ventricular permanent apical pacing

Resumen La estimulación apical permanente del ventrículo derecho (VD) puede producir asincronía del ventrículo izquierdo (VI) desde los puntos de vista eléctrico y mecánico. Este fenómeno es efecto de una alteración de la activación normal del VI que lleva al deterioro de la función sistólica y la aparición de insuficiencia cardíaca y sus efectos deletéreos relacionados. Para el estudio de la asincronía eléctrica del VI se ha propuesto en fecha reciente el nuevo sistema electrocardiográfico no invasivo Synchromax, que puede cuantificar el grado de asincronía eléctrica que causa una subsecuente asincronía mecánica. Esta última se ha estudiado casi siempre mediante la ecocardiografía transtorácica bidimensional (ETT2D) a través del Doppler tisular y la deformación miocárdica y ahora con la ecocardiografía tridimensional transtorácica en tiempo real (E3DTR). La relación entre estos fenómenos ha sido motivo de estudio a fin de identificar a los pacientes que se benefician de la transición a un tratamiento de resincronización cardíaca. Conclusiones: La estimulación artificial permanente del VD produce asincronía eléctrica del VI que puede cuantificarse mediante el nuevo sistema electrocardiográfico Synchromax y desencadenar asincronía mecánica estudiada mediante la ecocardiografía transtorácica para reconocer a los pacientes que pueden beneficiarse de un tratamiento de resincronización cardíaca.

Abstract Permanent apical pacing of right ventricle (RV) can produce dyssynchrony of the left ventricle (LV) from an electrical and mechanical point of view. This phenomenon is caused by an alteration in the normal activation of LV leading to a deterioration of systolic function and the appearance of heart failure and its associated deleterious effects. For the study of the electrical asynchrony of the LV, a new noninvasive electrocardiographic system Synchromax has recently been proposed, being able to quantify the degree of electrical asynchrony that leads to a subsequent mechanical dyssynchrony. The latter has been traditionally studied by two-dimensional transthoracic echocardiography (2DTTE) through tissue Doppler and myocardial deformation and lately by real-time 3-dimensional echocardiography (RT3DE). The relationship between these phenomena has been the subject of study to predict those patients who benefit from an “upgrade” to cardiac resynchronization therapy. Conclusions: Permanent apical pacing of the RV produces electrical dyssynchrony of the LV that can be quantified using a new electrocardiographic system Synchromax and trigger mechanical asynchrony studied through transthoracic echocardiography allowing to predict those patients who benefit from cardiac resynchronization therapy.

Resultados del primer registro de implante de cardiodesfibriladores y resincronizadores SAC (RENCARE) / Results of the First SAC Implantable Cardioverter-Defibrillator and Cardiac Resynchronization Therapy Registry (RENCARE)

RESUMEN Introducción: La prevención de la muerte súbita y el tratamiento de la insuficiencia cardíaca son temas de gran importancia. Para prevenir la muerte súbita y mejorar el pronóstico de la insuficiencia cardíaca se utilizan los cardiodesfibriladores y cardioresincronizadores. Objetivos: Evaluar la cantidad y tipo de dispositivos implantados en nuestro país, así como las características de los pacientes, las complicaciones agudas y las que se presentan en el seguimiento. Material y métodos: Se realizó un estudio observacional, prospectivo, multicéntrico en centros de salud con la capacidad de implantar cardiodesfibriladores y cardioresincronizadores. Se incluyeron pacientes a los que se les realizó implante de estos dispositivos desde enero del 2016 hasta enero de 2017, con un seguimiento de 12 meses. Resultados: Se incluyeron 249 pacientes (edad promedio de 64,8 ± 13,7 años, 73,9% de sexo masculino, 72,1% con Fey < 35%). La etiología subyacente de la miocardiopatía era isquémica en el 39,8%, dilatada 26,7% y chagásica en el 11,2% de los casos. El 58% de los implantes realizados fueron cardiodesfibriladores y el 39%, cardiodesfibriladores asociados con cardioresincronizadores. El 84% de los procedimientos fueron primoimplantes. La indicación más frecuente del implante fue por prevención primaria de muerte súbita (67,9%). La tasa de complicaciones menores fue del 4,4% y no se reportaron complicaciones mayores. Conclusiones: El siguiente registro evidenció una gran proporción de implantes en pacientes con cardiopatía isquémica, la indicación principal fue por prevención primaria de muerte súbita y la tasa de complicaciones fue similar a la reportada internacionalmente.

ABSTRACT Background: Prevention of sudden death and treatment of heart failure are very important topics. Implantable cardioverter-defibrillator and cardiac resynchronization devices are used to prevent sudden death and improve heart failure symptoms and prognosis. Objectives: The aim of this study was to evaluate the number, type of implanted devices, clinical characteristics of the patients and acute and follow-up complications. Methods: An observational, prospective, multicenter study was carried out in healthcare centers with the capacity to implant cardioverter-defibrillator and cardiac resynchronization devices. The study included all patients who underwent implantation of these devices from January 2016 to January 2017, with a 12-month follow-up. Results: A total of 249 patients (73.9% men) with mean age of 64.8±13.7 years, and 72.1% with ejection fraction <35%, were included in the study. The underlying cardiomyopathy etiology was ischemic in 39.8% of cases, dilated in 26.7% and chagasic in 11.2%. Fifty-eight percent of implants were implantable cardioverter-defibrillators and 39% were cardioverter-defibrillators associated with cardiac resynchronization devices. In 84% of cases, procedures were first implants. The most frequent indica-tion of implantation was for primary prevention of sudden death (67.9%). Minor complication rate was 4.4% and no major complications were reported. Conclusions: The present registry evidenced a large proportion of cardioverter-defibrillator and cardiac resynchronization implants in patients with ischemic heart disease. The main indication was for primary prevention of sudden death and the complication rate was similar to that reported internationally.