Cardiac dysrhythmias in systemic sclerosis / Alteraciones del ritmo cardíaco en esclerosis sistémica

Systemic sclerosis is an immunological disorder characterized by tissue fibrosis and multi-organ dysfunction.1 The accompanying images exhibit electrocardiographic changes in severe systemic sclerosis. Advanced 3:1 atrioventricular block, best observed in Lead Vi, suggests extensive fibrosis of the conduction system (Image A). While one P wave is buried in the T wave (black arrows), two are evident (red arrows) along the isoelectric line. Bradyarrhythmia related prolonged QT interval, best measured in Lead II represents increased risk for torsades-de-pointes, a polymorphic ventricular tachyarrhythmia. Additionally, right bundle branch block with giant T wave inversions (T wave depth > 10 mm) in precordial leads V2- 4 suggests pulmonary hypertension. Post-induction the rhythm abruptly changes to torsades-de-pointes (Image B) necessitating defibrillation.

La esclerosis sistémica es un trastorno inmunológico caracterizado por fibrosis tisular y disfunción multiorgánica. 1 Las imágenes adjuntas muestran cambios electrocardiográficos en la esclerosis sistémica grave. El bloqueo auriculoventricular avanzado 3: 1, que se observa mejor en la derivación VI, sugiere una fibrosis extensa del sistema de conducción ( Imagen A ).Mientras que una onda P está enterrada en la onda T (flechas negras), dos son evidentes (flechas rojas) a lo largo de la línea isoeléctrica. El intervalo QT prolongado relacionado con bradiarritmia, mejor medido en la derivación II, representa un mayor riesgo de torsades-de-pointes, una taquiarritmia ventricular polimórfica. Además, el bloqueo de la rama derecha del haz con inversiones de la onda T gigante (profundidad de la onda T> 10 mm) en las derivaciones precordiales V2- 4 sugiere hipertensión pulmonar. Después de la inducción, el ritmo cambia abruptamente a torsades-de-pointes ( Imagen B ), lo que requiere desfibrilación.

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%.

Sgarbossa Criteria in Left Bundle Branch Block in a Hypertensive Emergency, a Case Report

Abstract Left bundle branch block and hypertensive emergency are very common conditions in clinical cardiovascular and emergency practice. Hypertensive emergency encompasses a spectrum of clinical presentations in which uncontrolled blood pressure leads to progressive end-organ dysfunction. Suspected acute myocardial infarction in the setting of a left bundle branch block presents a unique diagnostic and therapeutic challenge to the clinician. The diagnosis is especially difficult due to electrocardiographic changes caused by altered ventricular depolarization. However, reports on the use of the Sgarbossa's criteria during the management of hypertensive emergency are rare. My current case is a hypertensive emergency patient with acute chest pain and left bundle branch block. Sgarbossa's criteria were initially very weak and, over time, became highly suggestive of acute ST-segment elevation myocardial infarction. Interestingly, chest pain increased as the Sgarbossa's diagnostic criteria were met. Here, we present a case of developing ST-segment elevation myocardial infarction with left bundle branch block that is indicating for thrombolytic therapy. Thrombolytic therapy was strongly indicated because of a higher developing of Sgarbossa criteria scoring. Thus, the higher Sgarbossa criteria scoring in the case was the only indication for thrombolytic. Therefore, how did Sgarbossa criteria developing during the course of the case to indicating the need for thrombolytic therapy?

Disincronía ventricular inducida por fármacos y taquicardiomiopatía en un neonate / Drug-induced ventricular dissynchrony and tachycardiomyopathy in a newborn

Resumen La disfunción ventricular secundaria a disincronía eléctrica y mecánica es una complicación de la estimulación ventricular desde el ápex del ventrículo derecho. No existen informes de disincronía secundaria a los efectos de fármacos antiarrítmicos. Se presenta el caso de una niña de 10 días de vida con taquicardia supraventricular incesante que se internó en terapia intensiva neonatal. Se inició tratamiento con propranolol por vía oral y ante la persistencia de la taquicardia se agregó amiodarona endovenosa. La paciente estuvo predominantemente en taquicardia con frecuencias cardíacas entre 200 y 290 latidos por minuto durante una semana a pesar del tratamiento instaurado. La función ventricular fue normal en los ecocardiogramas realizados. Se agregó flecainida por vía oral al esquema de tratamiento y luego de 24 horas presentó una taquicardia más lenta con QRS ancho e imagen de bloqueo completo de rama izquierda. Un nuevo ecocardiograma evidenció deterioro de la función ventricular izquierda e insuficiencia mitral moderada lo que motivó la suspensión de la flecainida y el propranolol. A las 24 horas de la suspensión se observó la normalización de la función ventricular a pesar de la persistencia de episodios intermitentes de taquicardia. Se reinició el propranolol logrando el control de la taquicardia. La presencia de disincronía ventricular generada por el bloqueo de rama izquierda secundario al tratamiento farmacológico con flecainida constituye una novedosa explicación posible para el desarrollo de disfunción ventricular.

Abstract Ventricular dysfunction secondary to electrical and mechanical dyssynchrony in chronic right ventricular apical pacing is a well-recognized complication. There are no previous reports of pharmacologically induced dyssynchrony. A 10-day old infant with incessant supraventricular tachycardia was admitted to the neonatal intensive care unit. Therapy with oral propranolol was initiated and due to persistence of tachycardia intravenous amiodarone was administered. The patient remained predominantly in tachycardia with heart rates between 200-290 beats per minute for a week with serial echocardiograms showing preserved ventricular function. Oral flecainide was started. After 24 hours of treatment the patient developed a slower incessant wide QRS with a left bundle branch block pattern. The echocardiogram showed deterioration of left ventricular systolic function and moderate mitral regurgitation. Flecainide and propranolol were discontinued. The QRS complex narrowed and despite intermittent breakthroughs of supraventricular tachycardia, ventricular function normalized. Propranolol was restarted to achieve definitive control of the tachycardia. The presence of ventricular dyssynchrony generated by the left bundle branch block pattern secondary to pharmacological treatment with flecainide is a novel possible explanation for the development of ventricular dysfunction.

Bloqueo de rama enmascarado / Masquerading bundle branch block

RESUMEN El bloqueo de rama enmascarado es una forma poco frecuente de bloqueo bifascicular de la cual se desconoce su mecanismo con exactitud. Es más frecuente encontrarlo en pacientes de edad avanzada o aquellos con una cardiopatía estructural como: enfermedad coronaria, hipertrofia ventricular, miocardiopatías, miocarditis chagásica y degeneración idiopática del sistema excitoconductor del corazón. Su diagnóstico electrocardiográfico se obtiene por la presencia de ondas R altas y anchas en V1 (patrón de bloqueo de rama derecha), desviación del eje eléctrico a la izquierda (entre -80 y -120 grados) y una onda S inferior a 1 mm o ausente en DI y aVL. Su presencia denota un factor de mal pronóstico en los pacientes.

ABSTRACT Masquerading bundle branch block is a rare form of bifascicular block, whose exact mechanism is unknown. It is more frequently found in elderly patients or those with structural heart disease such as: coronary artery disease, ventricular hypertrophy, cardiomyopathies, Chagas myocarditis and idiopathic degeneration of the cardiac conduction system. Its electrocardiographic diagnosis is obtained by the presence of high and wide R waves in V1 (right bundle branch block pattern), left axis deviation (between -80 and -120 degrees) and an S wave of less than 1 mm or absent in I and aVL leads. Its presence denotes a poor prognostic factor in patients.

Diagnóstico diferencial de las taquicardias de complejo ancho: un desafío permanente / Wide QRS tachycardia: a diagnostic challenge

El diagnóstico electrocardiográfico correcto de la causa de una taquicardia de complejo QRS ancho (TCA) es fundamental, ya que tanto el manejo, como el pronóstico del paciente, es diferente según su etiología, y define el estudio que debemos realizar. Numerosos criterios y algoritmos han sido descritos para diferenciar el origen de estas taquicardias. Sin embargo, muchos de estos son complejos y difíciles de aplicar para el médico menos experimentado. Esto es particularmente importante en los servicios de emergencia, donde se necesita una definición rápida que permita un manejo agudo apropiado. En la presente revisión analizamos los diferentes mecanismos de las TCA y los principales criterios diagnósticos en el ECG, reforzando, especialmente, aquellos de aplicación rápida y de alto rendimiento diagnóstico.

The correct electrocardiographic diagnosis of the cause of a wide QRS complex tachycardia (WCT) is essential since both management and prognosis of the patient. The correct electrocardiographic diagnosis of the cause of a wide QRS complex tachycardia (WCT) is essential since both management and prognosis is different according to its etiology and defines the study that we should perform. Numerous criteria and algorithms have been described to differentiate the origin of these tachycardias. However, many of these are complex and difficult to apply to the less experienced doctor. This is particularly important in emergency rooms, where a rapid definition is needed to allow proper therapy. In this review we analyze the different mechanisms of WCT and the main EKG diagnostic criteria, emphasizing those which can be applied rapidly and have high diagnostic value.

Incidence of Conduction Disorders and Requirements for Permanent Pacemaker After Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) has become a therapeutic option for high-risk or non-operable patients with severe symptomatic aortic stenosis. Atrioventricular conduction disturbances requiring permanent pacemaker (PPM) are a common and clinically important complication. Objectives: To evaluate the incidence of conduction disorders (CDs) after TAVI and the need for subsequent PPM implantation. To identify the predictors of postoperative PPM implantation. Methods: Retrospective study. All patients who underwent TAVI in a public hospital from December/2011 to June/2016 were included. Multivariate analysis was conducted to establish the predictor of permanent pacemaker implantation. Survival curves were constructed by the Kaplan-Meyer method. Statistically significant variables were those with p value < 0.05. Results: 64 patients with AS underwent TAVI. Eleven patients were excluded. TAVI induced a new CD in 40 (77%) of the remaining 53 patients. The most common new CDs were 3rd degree AV block (32%) and left bundle branch block (30%). Sixteen patients (30,2%) underwent PPM implantation during the index hospitalization. On univariate analysis the risk factors for PPM implantation were CoreValve® use (OR: 1,76; P = 0,005), larger prosthesis implantation (P = 0,015), presence of a QRS ≥ 120 ms (OR: 5,62; P = 0,012), and 1st degree AV block (OR: 13; P = 0.008). On multivariate analysis the presence of 1st degree AV block predicted the need for PPM. Conclusion: TAVI induced CDs requiring PPM in 30% of the patients. The presence of 1st degree AV block predicted the need for PPM

Bloqueo de rama alternante en una taquicardia supraventricular: ¿Cuál es el mecanismo subyacente? / Alternating bundle branch block in a supraventricular tachycardia: Which is the mechanism ?

El bloqueo de rama funcional durante una taquicardia supraventricular puede ser observado con longitudes de ciclo cortas y representa una respuesta fisiológica del sistema de conducción intraventricular por la existencia de conducción nodal auriculo ventricular acelerada. Presentamos el caso de un paciente joven con taquicardia reentrante aurículo-ventricular ortodrómica y bloqueo de rama alternante. Esta respuesta infrecuente se explica por el hallazgo obtenido durante el estudio electrofisiológico. Una conducción nodal aurículo-ventricular acelerada produce un frente de onda que despolariza las ramas durante sus períodos refractarios. Una vez que ocurrió el bloqueo en una de las ramas, dicho bloqueo persistió debido al fenómeno de linking, que es por conducción oculta retrógrada repetitiva de la rama contralateral. Después de la ablación transcatéter de una vía accesoria oculta lateral izquierda, el marcapaseo auricular rápido a la misma longitud de ciclo de la taquicardia, reprodujo la misma aberrancia observada durante la taquicardia. Este procedimiento demostró que el bloqueo de rama funcional fue debido a la longitud de ciclo corto y no a la presencia de una vía accesoria aurículo-ventricular.

Functional bundle branch block during a supraventricular tachycardia can be observed with shorter cycle lengths and represent a physiologic response by the specialized intraventricular conduction system to accelerated AV nodal conduction. The present case corresponds to a young patient with exercise induced orthodromic A-V reentrant tachycardia and alternating bundle branch block. This unusual response is explained by the finding obtained during the electrophysiology study. An accelerated AV nodal conduction made the depolarizing wave front reach the bundle branches during their refractory period. Once block in one bundle was stablished, block persisted due to the linking phenomenon that is repetitive retrograde concealed conduction from the contralateral bundle. After catheter ablation of a concealed left-sided accessory A-V pathway, rapid atrial pacing at the same cycle length of the tachycardia reproduced the same aberrancies observed during tachycardia. This response proved that functional bundle branch block is due to the short cycle length and not the presence of an accessory A-V pathway.

Bloqueo de rama izquierda como equivalente ST, ¿cuándo sí, cuándo no? / Left bundle branch block as equivalent of ST-segment elevation myocardial infarction: when yes, when not?

Resumen La presencia de un bloqueo de rama izquierda del haz de His nuevo o presumiblemente nuevo junto con síntomas isquémicos se ha considerado tradicionalmente un equivalente electrocardiográfico de infarto agudo de miocardio con elevación del segmento ST, el cual debe ser llevado a reperfusión emergente. Para su definición se han propuesto varios criterios, pero ninguno ha alcanzado un rendimiento diagnóstico óptimo. A continuación detallaremos dichos criterios, sus principales problemas y las ventajas que han demostrado.

Abstract A new or presumably new left bundle branch block along with ischemic symptoms has traditionally been considered an electrocardiographic equivalent of ST-segment elevation myocardial infarction, which should be brought to emergent reperfusion. However, several criteria have been proposed for its definition, but none has reached out an optimal diagnostic yield. Below we detail these criteria, their main problems and the advantages they have shown.

Electrocardiographic changes in spondyloarthritis and use of anti-TNF-α drugs: a retrospective study with 100 patients / Alterações eletrocardiográficas em espondiloartrites e uso de anti-TNF-α: estudo retrospectivo em 100 pacientes

ABSTRACT Objective To investigate the prevalence of electrocardiographic changes in patients with spondyloarthritis and to correlate these changes with use of anti-tumor necrosis factor-alpha (TNF-α) drugs and HLA-B27 positivity. Methods Retrospective study including 100 patients diagnosed with spondyloarthritis according to Assessment of SpondyloArthritis International Society (ASAS) criteria and 50 controls. Epidemiological and clinical features, results of inflammatory activity tests, HLA-B27 positivity, and medication use data were extracted from medical records. Disease activity was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). All participants were submitted to electrocardiogram performed using a 12-lead device; rhythm, heart rate, conduction disorders and QT interval corrected using the Bazett formula were analyzed. Results Of 100 patients with spondyloarthritis, 51 were on anti-TNF-α drugs and 49 were not. HLA-B27 was detected in 53.1% of patients in the sample. Patients with spondyloarthritis had lower heart rate (p=0.06), longer QT interval (p<0.0001) and higher prevalence of right bundle branch block (p=0.014) compared to controls. Duration of disease was weakly correlated with heart rate (Rho=0.26; 95%CI: 0.06-0.44; p=0.008). The prevalence of right bundle branch block was positively correlated with HLA-B27 positivity. Use of Anti-TNF-α drugs did not interfere with electrocardiographic parameters. Conclusion Patients with spondyloarthritis had lower heart rate, longer QT interval and a higher prevalence of right bundle branch block compared to controls. HLA-B27 positivity was associated with the prevalence of right bundle branch block. Anti-TNF-α drugs had no impact on electrocardiographic findings.

RESUMO Objetivo Avaliar a prevalência de alterações eletrocardiográficas em pacientes com espondiloartrites, correlacionando-as com o uso de medicações antifator de necrose tumoral alfa (TNF-α) e presença do HLA-B27. Métodos Estudo retrospectivo com 100 pacientes com diagnóstico de espondiloartrites pelo critério Assessment of SpondyloArthritis International Society (ASAS) e 50 controles. Foram coletados nos prontuários dos pacientes, dados epidemiológicos, clínicos, exames de atividade inflamatória, presença do HLA-B27, e uso de medicamentos. A atividade de doença foi avaliada pelo Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Todos foram submetidos a eletrocardiograma realizado com aparelho de 12 derivações, sendo analisados ritmo, frequência cardíaca, distúrbios de condução e intervalo QT corrigido pela fórmula de Bazett. Resultados Dos 100 pacientes com espondiloartrites, 49 não usavam anti-TNF-α e 51 utilizavam este medicamento. O HLA-B27 estava presente em 53,1% da amostra. A frequência cardíaca foi mais baixa (p=0,06), o intervalo QT foi mais prolongado (p<0,0001) e existia mais perturbação de condução do ramo direito (p=0,014) nos pacientes com espondiloartrites do que nos controles. Uma modesta correlação de tempo de doença com frequência cardíaca foi encontrada (Rho=0,26; IC95%: 0,06-0,44; p=0,008). A presença do HLA-B27 aumentou a prevalência de perturbação de condução do ramo direito. Nenhum dos parâmetros eletrocardiográficos analisados alterou-se com uso de anti-TNF-α. Conclusão Pacientes com espondiloartrites tiveram frequência cardíaca menor, maior intervalo QT e prevalência maior de perturbação de condução do ramo direito do que controles. O HLA-B27 influi no aparecimento de perturbação de condução do ramo direito. O uso de anti-TNF-α não influiu nos achados eletrocardiográficos.

Efecto de la terapia de resincronización ventricular en los parámetros de disfunción endotelial y función sistólica izquierda en pacientes con insuficiencia cardíaca crónica y bloqueo completo de rama izquierda / Endothelial dysfunction, left ventricular function, and chronic heart failure with complete left bundle branch block: effect of resynchronization therapy

Resumen: Introducción: La insuficiencia cardíaca crónica (ICC) es una condición compleja asociada a inflamación sistémica y a disfunción endotelial (DE) cuya patogénesis no es bien comprendida. Objetivo: Evaluar una posible relación entre marcadores de DE periférica con la respuesta a terapia de resincronización ventricular (TRV). Método: 20 pacientes con ICC, QRS ≥120ms y fracción de eyección ventricular izquierda (FEVI) ≤35% se estudiaron pre y 6 meses post-TRV con: Minnesota Living with Heart Failure Questionnaire (MLHFQ); test de marcha (TM-6min); Ecocardiografía-2D y SPECT de perfusión gatillado en reposo; proteína C-reactiva ultra sensible (us-PCR); péptido natriurético cerebral (pro-BNP); células endoteliales circulantes (CEC); moléculas de adhesión soluble vascular (sVCAM) e intercelular (sICAM); interleukina-6 (IL-6) y Factor von Willebrand (FvW). Se clasificaron como respondedores o no a TRV según criterios preestablecidos. Resultados: Promedios basales: pro-BNP 5.290pg/ml; us-PCR 1,7ug/mL; MLHFQ 72; TM-6min 391 metros. Las CEC y sICAM estaban sobre límites normales. Post-TRV, el 50% fue respondedor: 11/20 mejoraron ≥1 clase NYHA y ≥10% del TM-6min; ML-HFQ disminuyó (p<0.0001); FEVI mejoró (p=0.003); volumen final sistólico disminuyó (p=0.008) y también pro-BNP (p=0.03). En los respondedores, las CEC disminuyeron, persistiendo elevadas, sobre lo normal. Existieron correlaciones entre cambios de pro-BNP con TM-6min y entre us-PCR con MLHFQ y FvW (p≤0.004 en todas). Conclusiones: En ICC existe evidencia de significativa DE, expresada por sICAM y CEC, biomarcador periférico sensible. Estas disminuyeron 6 meses post-TRV, persistiendo sobre el límite normal. Otros parámetros funcionales e inflamatorios se correlacionaron en el grupo total, sin diferencias entre grupos respondedores y no respondedores.

Abstract: Introduction: Chronic heart failure (CHF) is a complex condition associated with systemic inflammation and endothelial dysfunction (ED) whose pathogenesis is not well understood. Objective: to evaluate a possible relationship between peripheral ED markers and response to cardiac resynchronization therapy (CRT). Method: 20 patients with CHF, QRS ≥120ms and left ventricular ejection fraction (LVEF) ≤35% were studied before and 6 months post-CRT. Minnesota Living with Heart Failure Questionnaire (MLHFQ); walking test (6min-WT); 2D-echocardiography and gated perfusion SPECT at rest; ultra-sensitive C-reactive protein (us-CRP); brain natriuretic peptide (pro-BNP); circulating endothelial cells (CEC); vascular soluble adhesion (sVCAM) and intercellular adhesion molecules (sICAM); interleukin-6 (IL-6) and von Willebrand Factor (vWF) were measured in all subjects. They were classified as responders or not to CRT, according to pre-established criteria. Results: Basal means: pro-BNP 5,290 pg / ml; us-CRP 1.7 ug/mL; MLHFQ 72; 6min-WT 391 meters. The CEC and IL-6 were above normal limits. Post-CRT, 50% were responders: 11/20 improved ≥1 NYHA class and ≥10% increase in 6min-WT; MLHFQ decreased (p <0.0001); LVEF improved (p = 0.003); final systolic volume decreased (p = 0.008) and also pro-BNP (p= 0.03). In responders CEC decreased, persisting over normal limits. There were correlations between changes of pro-BNP with TM-6min and between us-PCR with MLHFQ and vWF (p≤0.004 in all). Conclusions: In CHF there is evidence of significant ED, expressed by sICAM and CEC, a sensitive peripheral biomarker that decreased 6 months post-CRT although persisting above normal limits. Other functional and inflammatory parameters were correlated in the total group, without differences between responders and non-responders.