Teste de Limiar de Desfibrilação e Seguimento a Longo Prazo de Pacientes com Cardiopatia Crônica da Doença de Chagas / Defibrillation Threshold Testing and Long-term Follow-up in Chagas Disease

Resumo Fundamento A morte súbita cardíaca (MSC) é a causa mais comum de óbito na cardiomiopatia crônica da doença de Chagas (CCDC). Visto que muitos pacientes com CCDC que são candidatos a receber um cardioversor desfibrilador implantável (CDI) atendem a critérios que sugerem alto risco de apresentarem limiares de desfibrilação elevados, sugere-se realizar um teste de limite de desfibrilação (LDF). Objetivos Investigamos o uso do teste de LDF em pacientes com CCDC, com enfoque nos óbitos relacionados ao implante do CDI e na ocorrência de eventos arrítmicos e o tratamento oferecido durante o seguimento de longo prazo. Métodos Avaliações retrospectivas de 133 pacientes com CCDC que receberam CDI, principalmente para prevenção secundária. Foram coletados dados demográficos, clínicos e laboratoriais, escore de Rassi e dados do teste de LDF. Adotou-se p<0,05 como estatisticamente significativo. Resultados A média de idade foi 61±13 anos, e 72% da amostra era do sexo masculino. A fração de ejeção basal do ventrículo esquerdo foi 40±15%, e o escore de Rassi médio foi 10±4 pontos. Não ocorreram óbitos durante o teste de LDF, e não foram documentadas falhas do CDI. Foi identificada relação entre escore de Rassi basal mais elevado e LDFs mais elevados (ANOVA =0,007). O tempo médio até o primeiro choque foi de 474±628 dias, mas a aplicação de choque foi necessária em apenas 28 (35%) pacientes com TV, visto que a maioria dos casos se resolveu espontaneamente ou através da programação de ATP. Após seguimento clínico de 1728±1189 dias, em média, ocorreram 43 óbitos, relacionados principalmente a insuficiência cardíaca progressiva e sepse. Conclusões Um teste de LDF de rotina pode não ser necessário para pacientes com CCDCs que receberam CDI para prevenção secundária. LDFs elevados parecem ser incomuns e podem estar relacionados a escore de Rassi elevado.

Abstract Background Sudden cardiac death is the most common cause of death in chronic Chagas cardiomyopathy (CCC). Because most CCC patients who are candidates for implantable cardioverter-defibrillators (ICD) meet criteria for high defibrillation threshold values, a defibrillator threshold test (DTT) is suggested. Objectives We investigated the use of DTT in CCC patients, focusing on deaths related to ICD and arrhythmic events, as well as treatment during long-term follow-up. Methods We retrospectively evaluated 133 CCC patients who received an ICD mainly for secondary prevention. Demographic, clinical, laboratory data, Rassi score, and DTT data were collected, with p < 0.05 considered significant. Results The mean patient age was 61 (SD, 13) years and 72% were men. The baseline left ventricular ejection fraction was 40 (SD, 15%) and the mean Rassi score was 10 (SD, 4). No deaths occurred during DTT and no ICD failures were documented. There was a relationship between higher baseline Rassi scores and higher DTT scores (ANOVA = 0.007). The mean time to first shock was 474 (SD, 628) days, although shock was only necessary for 28 (35%) patients with ventricular tachycardia, since most cases resolved spontaneously or through antitachycardia pacing. After a mean clinical follow-up of 1728 (SD, 1189) days, 43 deaths occurred, mainly related to progressive heart failure and sepsis. Conclusions A routine DTT may not be necessary for CCC patients who receive an ICD for secondary prevention. High DTT values seem to be unusual and may be related to high Rassi scores.

Association between ventricular premature contraction burden and ventricular repolarization duration

SUMMARY OBJECTIVE: Premature ventricular contraction is generally known as benign in the absence of structural heart disease; however, premature ventricular contraction-induced left ventricular systolic dysfunction or ventricular arrhythmias are defined in some cases. Ventricular repolarization duration differs between myocardial cells, which causes myocardial electrical heterogeneity and is thought to be responsible for ventricular arrhythmias. In our study, we aimed to evaluate the association of ventricular repolarization parameters including Tp-Te interval, Tp-Te/QT ratio, and QRS-T angle with premature ventricular contraction frequency in patients with premature ventricular contraction burden. METHODS: A total of 80 subjects who were admitted to our cardiology department and underwent 24-h electrocardiography Holter monitoring were included. Patients were divided into two groups: group 1 is defined as premature ventricular contraction burden that had frequent premature ventricular contraction ≥1% in 24-h Holter monitoring, and group 2 is defined as rare premature ventricular contraction <1% in 24-h Holter monitoring. RESULTS: Tp-Te interval and Tp-Te/QT ratio are statistically significantly prolonged in the premature ventricular contraction burden group than in the control group (85.3±13.9 vs. 65.7±11.9, p<0.001; 0.19±0.03 vs. 0.15±0.02, p<0.001, respectively). QRS-T angle was statistically significantly abnormal in the premature ventricular contraction burden group (p=0.024). CONCLUSION: Increased Tp-Te interval and widened QRS-T angle are associated with ventricular arrhythmias and might be used for the prediction of premature ventricular contraction burden in patients with premature ventricular contraction in electrocardiography in the absence of 24-h Holter monitoring.

Validação de um Algoritmo Simples para Detecção de Taquicardia Ventricular no Eletrocardiograma / Validation of a Simple Electrocardiographic Algorithm for Detection of Ventricular Tachycardia

Resumo Fundamento O diagnóstico diferencial de taquicardia de QRS largo, entre taquicardia ventricular (TV) ou taquicardia supraventricular com condução aberrante (TSV-A) é algumas vezes difícil de ser feito na sala de emergência. Objetivo Avaliar a acurácia de um algoritmo novo e simples para a detecção de TV no eletrocardiograma (ECG) em pacientes com taquicardia de QRS largo. Métodos ECGs de 12 derivações para detecção de taquicardia de QRS largo foram obtidos prospectivamente de 120 pacientes durante estudo eletrofisiológico. Seis médicos com diferentes experiências analisaram os ECGs, e fizeram o diagnóstico com base no algoritmo D12V16, que envolve a análise da polaridade predominante do complexo QRS nas derivações I, II, V1 e V6. O diagnóstico foi comparado com os obtidos pelo algoritmo tradicional de Brugada e pelo estudo eletrofisiológico, o qual é considerado padrão ouro. Adotou-se um nível de significância de 5% (p<0,05) nas análises estatísticas. Resultados De acordo com o estudo eletrofisiológico, 82 ECGs eram de TV e 38 de TSV-A. Doenças cardíacas estruturais estavam presentes em 71 (86,6%) dos pacientes com TV e em oito (21,1%) com TSV-A. O algoritmo de Brugada teve uma maior sensibilidade global (87,2%), enquanto o algoritmo D12V16 apresentou maior especificidade global (85,1%) para TV. Tanto o algoritmo D12V16 como o de Brugada apresentou um alto valor preditivo positivo (90,9% vs. 85,8%, respectivamente) e acurácia similar (73,8% vs. 81,4%, respectivamente) para o diagnóstico de TV. Nos avaliadores experientes, a acurácia foi maior utilizando o algoritmo de Brugada que o algoritmo D12V16, mas a acurácia dos dois algoritmos foi similar segundo os avaliadores menos experientes. Conclusão O algoritmo simplificado pode ser um método útil para reconhecer TV no ECG, principalmente para médicos menos experientes. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

Abstract Background The differential diagnosis of wide QRS complex tachycardia (WCT) between ventricular tachycardia (VT) or supraventricular tachycardia with aberrant conduction (SVT-A) is sometimes difficult in the emergency room. Objective The aim of this study was to evaluate the accuracy of a new simple electrocardiographic algorithm to recognize VT in patients with wide complex tachycardia. Methods The 12-lead electrocardiograms (ECG) for WCT were prospectively obtained from 120 patients during electrophysiological study. Six physicians with different expertise analyzed the electrocardiographic recordings, and made the diagnosis based on the D12V16 algorithm, that involves the analysis of the predominant polarity of QRS in leads I, II, V1 and V6. The diagnosis was compared with that made using the traditional Brugada algorithm and the "gold-standard" electrophysiological study. Statistical analyses were performed with a significance level of 5% (p<0.05). Results According to the EPS study, 82 ECG recordings were VT and 38 SVT-A. Structural heart diseases were present in 71 (86.6%) patients with VT and in 8 (21.1%) with SVT-A. The Brugada algorithm had higher global sensitivity (87.2%), and the D12V16 algorithm had higher global specificity (85.1%) for VT. Both D12V16 and Brugada's algorithms presented a high positive predictive value (90.9% vs 85.8%, respectively) and similar accuracy (73.8% vs 81.4%, respectively) for the diagnosis of VT. Experienced evaluators were more accurate using Brugada algorithm than the D12V16 algorithm, but the accuracy of both algorithms was similar according to less experienced examiners. Conclusion The simplified algorithm may be a useful method to recognize VT in the ECG, especially for less experienced doctors. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

Effects of Danhong injection combined with bisoprolol on ventricular arrhythmia in patients with type 2 diabetes mellitus complicated by coronary heart disease / 中国基层医药

Objective:To investigate the efficacy and safety of Danhong injection combined with Bisoprolol on ventricular arrhythmia in patients with type 2 diabetes mellitus complicated by coronary heart disease. Methods:A total of 100 patents with type 2 diabetes mellitus complicated by coronary heart disease who received treatment in Dezhou Second People's Hospital, China between January and December 2019 were included in this study. They were randomly assigned to receive treatment either with bisoprolol (control group, n = 50) or bisoprolol + Danhong injection (treatment group, n = 50) based on routine treatment. Therapeutic effects, arrhythmia improvement, blood glucose index, islet function index, and adverse reactions during treatment were compared between the control and treatment groups. Results:Total effective rate in the observation group was significantly higher than that in the control group (88.0% vs. 70.0%, χ2 = 4.883, P < 0.05). After treatment, there were significant differences in the number of ventricular premature beats [(1 412.52 ± 587.85) beats/24 hours vs. (2 247.96 ± 761.52) beats/24 hours], paroxysmal supraventricular tachycardia [(46.58 ± 10.12) bursts/24 hours vs. (79.45 ± 12.01) bursts/24 hours], and ST segment depression [(1.24 ± 0.19) mm vs. (1.41 ± 0.24) mm] between the observation and control groups ( t = -6.141, -14.799, -3.927, all P < 0.001). After treatment, fasting blood glucose level, 2-hour postprandial glucose value and glycosylated hemoglobin level in the treatment group were (6.58 ± 1.61) mmol/L, (8.35 ± 1.72) mmol/L, and (6.14 ± 1.58)%, respectively, which were significantly lower than those in the control group [(8.24 ± 1.87) mmol/L, (9.69 ± 1.91) mmol/L, (7.68 ± 1.92)%, t = -4.757, -3.686, -4.379, all P < 0.001]. After treatment, islet beta cell function in the observation group was significantly higher than that in the control group [(56.52 ± 10.28) % vs. (47.96 ± 9.72)%, t = 4.278, P < 0.001). Insulin resistance index in the observation group was significantly lower than that in the control group [(2.06 ± 0.32) vs. (2.54 ± 0.35), t = -7.157, P < 0.001]. After treatment, there was no significant difference in the incidence of adverse reactions between the control and observation groups (12.00% vs. 8.00%), χ2 = 0.444, P > 0.05]. Conclusion:Danhong injection combined with bisoprolol is more effective in treating ventricular arrhythmia in patients with type 2 diabetes mellitus complicated by coronary heart disease than Danhong injection and bisoprolol alone. The combined treatment can reduce the incidence of ventricular arrhythmia, regulate blood glucose level, and improve islet function.

Muerte súbita en el ámbito prehospitalario en época de COVID-19 / Sudden death in the prehospital setting in times of COVID-19

RESUMEN Una de cada cinco muertes de adultos en países desarrollados se debe a causas cardiovasculares; la mitad de esas muertes se produce de forma súbita y un gran porcentaje en el ámbito extrahospitalario. Múltiples estudios demostraron que el acceso de la población general al aprendizaje de maniobras de reanimación cardiopulmonar sencillas y pragmáticas y la presencia de desfibrilador externo automático se traducen en un gran aumento de sobrevida sin secuelas en casos de muerte súbita cardíaca extrahospitalaria. Hoy en día existe una situación especial representada por la pandemia por COVID -19, que deja bajo un interrogante todo lo aprendido hasta la fecha y nos enfrenta a dos situaciones sumamente complejas. Por un lado, la afectación cardiovascular y el aumento consecuente de arritmias ventriculares malignas que genera esta infección, tanto en pacientes sanos como en sujetos con patologías preexistentes, han puesto de manifiesto un aumento en la incidencia de episodios de muerte súbita extrahospitalaria. Por otro lado, se vuelve necesario reevaluar todo el accionar puesto en marcha cuando un paciente presenta un episodio de muerte súbita cardíaca extrahospitalaria, ya que ahora se agrega la posibilidad de transmisión de esta enfermedad de alta contagiosidad durante las maniobras de reanimación. Volver a encontrar un equilibrio riesgo-beneficio que permita aumentar la sobrevida del paciente con el mínimo riesgo posible para la persona que realiza la reanimación es el verdadero desafío hoy en día.

ABSTRACT One in five adult deaths in developed countries is due to cardiovascular causes; half of these deaths occur suddenly and a large percentage in the out-of-hospital setting. Multiple studies demonstrated that the access of the general population to learning simple and pragmatic cardiopulmonary resuscitation maneuvers and the presence of automatic external defibrillator translates into a large increase in survival without sequelae in victims of sudden out-of-hospital sudden cardiac death. Today there is a situation represented by the pandemic by COVID -19, which questions what we have learned to date and makes us face two extremely complex situations. On the one hand, the cardiovascular involvement and the consequent increase in malignant ventricular arrhythmias generated by this infection, both in patients with previous pathologies or not, has shown an increase in the incidence of episodes of sudden out-of-hospital death. On the other hand, it forces us to rethink all the actions put into place at the moment that a patient presents with an episode of sudden out-of-hospital sudden cardiac death since now the possibility of transmission of this highly contagious disease is added during resuscitation maneuvers. Refinding a risk-benefit balance that allows increasing the patient's survival with the least possible risk for the person who is resuscitating is the real challenge we are facing today.

Isolated Non-Compacted Myocardium: Should We Consider the Presence of Extrasystoles as the Initial Manifestation?

Ventricular non-compaction occurs due to failure in myocardial morphogenesis during the fetal period. Patients can have heart failure, as well as systemic complications due to thromboembolism and cardiac arrhythmias. Early diagnosis is essential. We present the case of an asymptomatic 49-year-old woman who initially manifested ventricular extrasystoles and heart failure with reduced ejection fraction and a myocardial noncompaction diagnosis

Combined epicardial and transapical endocardial radiofrequency ablation for ventricular tachycardia with ventricular aneurysm in a porcine model / 中华胸心血管外科杂志

Objective@#To evaluate the feasibility and validity of combined directly epicardial and transapical endocardial substrate ablation guided by Carto mapping for ventricular tachycardia(VT) with left ventricular aneurysm(LVA) intra-operation in a swine model.@*Methods@#Twenty-four swine models with sustained VT and LVA were randomly divided into study group(radiofrequency ablation, RFCA, from epicardium via direct-view and endocardium via transapical access, 12 cases) and control group(endocardial RFCA via retrograde transaortic access, 12 cases). Substrate mapping for captured abnormal potentials via endocardium and epicardium was used to precisely locate the low-voltage areas. After ablation in two groups, VT was induced again to compare the effectiveness of different RFCA strategies.@*Results@#Three dimensional electro-anatomic mapping was implemented successfully in two groups under open chest. And VT substrates were largely located in the border zone of LVA. All objects in the study group underwent endocardial ablation via transapical access smoothly without operative failure. When VT inducing again, 2 cases of study group was with inducible VT, however, VT recurrence in control group was 5 cases, P=0.04.@*Conclusion@#Combined direct epicardial and transapical endocardial substrate mapping and ablation appeared to be feasible and effective for treating VT with LVA under thoracotomy.

Intravenous lipid emulsion therapy for cardiac arrest and refractory ventricular tachycardia due to multiple herb intoxication

Herbal products have been used for therapeutic purposes for a long time. However, many herbs can be toxic and even life-threatening. If refractory ventricular tachycardia (VT) is caused by herbal products and shows no response to conventional therapy, intravenous lipid emulsion (ILE) therapy can be considered. We report a case of herbal intoxication leading to refractory VT, which was successfully treated with ILE therapy. A 36-year-old woman with aplastic anemia presented with mental changes. She had taken an unknown herbal decoction three days before visiting the hospital. Soon after coming to the hospital, she went into cardiac arrest. Cardiopulmonary resuscitation was performed, and return of spontaneous circulation with VT was achieved. Synchronized cardioversion was then performed and amiodarone was administered. However, VT with pulse continued, so ILE therapy was attempted, which led to the resolution of VT.

Mycophenolate Mofetil Overdose Induced Ventricular Tachycardia in a Patient with Systemic Lupus Erythematosus / 대한내과학회지

Mycophenolate mofetil (MMF) is an immunosuppressive agent used to treat severe lupus, including lupus nephritis. Common adverse effects of MMF include gastrointestinal and hematological manifestations; however, cardiac toxicity in association with MMF has not been reported. We present a 21-year-old woman with lupus nephritis who developed ventricular tachycardia 2 hours after an overdose of MMF (34 g). Ventricular bigeminy was documented 12 hours after the MMF overdose. Transthoracic echocardiography showed no evidence of structural heart disease. The ventricular arrhythmia was successfully treated with potassium replacement, hydration, and cholestyramine. This case suggests that an overdose of MMF can induce ventricular tachycardia, and electrocardiogram monitoring is critical to identify this rare cardiac complication of MMF.

Dispersión del intervalo QT corregido como predictor de arritmias ventriculares en el infarto agudo del miocardio / Dispersion of the corrected QT interval as a predictor of ventricular arrhythmias in acute myocardial infarction

RESUMEN Fundamento: La dispersión del intervalo QT es un marcador electrocardiográfico que puede resultar útil en la estratificación de riesgo arrítmicos en pacientes con infarto agudo del miocardio. Objetivo: Describir la influencia de la dispersión del intervalo QT corregido en asociación a otros factores de riesgo como predictores de arritmias ventriculares en el infarto agudo del miocardio con elevación del segmento ST. Metodología: Se estudiaron de menera prospectiva 209 pacientes que ingresaron de forma consecutiva con diagnóstico de infarto agudo de miocardio con elevación del segmento ST de enero de 2013 a junio de 2014 en el Hospital Provincial General Camilo Cienfuegos de Sancti Spíritus. Se recogieron datos clínicos, de laboratorio electrocardiográficos y ecocardiográficos; se determinó la implicación pronóstica de la dispersión del intervalo QT corregido en la aparición de arritmias ventriculares a través de la regresión logística binaria y las curvas de operador-receptor. Resultados: Las arritmias ventriculares se presentaron en 39 (18.7 %) pacientes. La dispersión del QT corregido mostró una adecuada capacidad de discriminación en la predicción de cualquier episodio arrítmico ventricular grave (c=0.768, p=0.0001). En el análisis multivariado la dispersión del QT resultó un predictor independiente de arritmias ventriculares (OR= 7.075; IC 95%= 1.6- 32.9; p=0.009). Conclusiones: La probabilidad de presentar arritmias ventriculares durante el infarto agudo del miocardio es mayor cuando se incrementan la dispersión del intervalo QT, por lo que se sugiere debe ser una variable a evaluar en la estratificación pronostica del infarto agudo del miocardio.

ABSTRACT Background: Dispersion of the QT interval is an electrocardiographic marker that can be useful in the stratification of arrhythmic risk in patients with acute myocardial infarction. Objective: To describe the influence of corrected QT interval dispersion in association with other risk factors as predictors of ventricular arrhythmias in acute myocardial infarction with ST-segment elevation. Methodology: 209 patients who entered consecutively with diagnosis of acute myocardial infarction with elevation of the ST segment from January 2013 to June 2014 at Camilo Cienfuegos General Provincial Hospital of Sancti Spíritus were studied prospectively. Clinical, electrocardiographic and echocardiographic laboratory data were collected; the prognostic implication of the corrected QT interval dispersion in the appearance of ventricular arrhythmias through binary logistic regression and operator-receiver curves was determined. Results: Ventricular arrhythmias occurred in 39 (18.7%) patients. The dispersion of the corrected QT showed an adequate discrimination capacity in the prediction of any serious ventricular arrhythmic episode (c = 0.768, p = 0.0001). In the multivariate analysis, QT dispersion was an independent predictor of ventricular arrhythmias (OR = 7.075, 95% CI = 1.6-32.9, p = 0.009). Conclusions: The probability of presenting ventricular arrhythmias during acute myocardial infarction is greater when the dispersion of the QT interval is increased, so it is suggested that it should be a variable to be evaluated in the prognostic stratification of acute myocardial infarction.

Trasplante cardiaco en paciente bipolar: reporte de caso / Bipolar Disorder and Heart Transplantation: A Case Report

RESUMEN Introducción: El trastorno bipolar es una afección del estado de ánimo, crónico y recurrente, que cursa con síntomas que fluctúan entre la euforia y la depresión. El trasplante cardiaco es el tratamiento de elección para pacientes con insuficiencia cardiaca y arritmias que no responden al tratamiento convencional, pero este tipo de procedimiento está contraindicado de manera absoluta o relativa para pacientes con trastorno bipolar. Métodos: Reporte de caso y revisión narrativa de la literatura. Caso: Mujer de 34 arios con trastorno bipolar desde los 13, en tratamiento con litio y aripiprazol, que requirió un trasplante cardiaco como opción terapéutica por taquicardia ventricular refractaria al tratamiento convencional. La paciente no sufrió descompensación afectiva al retirársele el litio y el aripiprazol, que se debió suspender porque se asociaron con prolongación del intervalo QTc, y permaneció eutímica a lo largo del proceso con ácido valproico y clonazepam. Conclusiones: Este reporte de caso muestra un trasplante cardiaco exitoso en una paciente con trastorno afectivo bipolar en eutimia y sin otras contraindicaciones psicosociales para el injerto. Además, destaca la importancia del seguimiento por psiquiatría de enlace durante el proceso.

ABSTRACT Introduction: Bipolar disorder is a chronic and recurrent mood disease that includes symptoms that fluctuate from euphoria to depression. As a mood disorder, itis one of the main contraindications for transplantation procedures. The case is presented of a patient with bipolar disorder who had a heart transplant after a cardiac arrest. Heart transplantation is the treatment of choice in patients with heart failure and arrhythmias that do not respond to conventional treatment. Methods: Case report and narrative review of literature. Case report: A 34-year-old woman with bipolar disorder diagnosed when she was 13, treated with lithium and aripiprazole. She required a heart transplant as the only therapeutic option, after presenting with ventricular tachycardia refractory to conventional treatment. The patient did not suffer an emotional decompensation with the removal of the lithium and aripiprazole that were associated with prolonged QTc interval, and remained eurhythmic throughout the process. Discussion: Heart transplantation can be performed safely and successfully in patients with bipolar disorder, when suitably followed-up by a liaison psychiatry group. Conclusions: Bipolar disorder should not be considered as an absolute contraindication for heart transplantation.