RESUMO
PURPOSE OF REVIEW: More than a century since its discovery, the pathogenesis of Chagas heart disease (CHD) remains incompletely understood. The role of derangements in the autonomic control of the heart in triggering malignant arrhythmia before the appearance of contractile ventricular impairment was reviewed. RECENT FINDINGS: Although previous investigations had demonstrated the anatomical and functional consequences of parasympathetic dysautonomia upon the heart rate control, only recently, coronary microvascular disturbances and sympathetic denervation at the ventricular level have been reported in patients and experimental models of CHD, exploring with nuclear medicine methods their impact on the progression of myocardial dysfunction and cardiac arrhythmias. More important than parasympathetic impaired sinus node regulation, recent evidence indicates that myocardial sympathetic denervation associated with coronary microvascular derangements is causally related to myocardial injury and arrhythmia in CHD. Additionally, 123I-MIBG imaging is a promising tool for risk stratification of progression of ventricular dysfunction and sudden death.
Assuntos
Cardiomiopatia Chagásica , Simpatectomia , Humanos , Simpatectomia/métodos , Cardiomiopatia Chagásica/fisiopatologia , Cardiomiopatia Chagásica/cirurgia , Cardiomiopatia Chagásica/complicações , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Coração/inervação , Coração/diagnóstico por imagem , 3-Iodobenzilguanidina , Sistema Nervoso Simpático/fisiopatologiaRESUMO
BACKGROUND: Sudden cardiac death (SCD) can be the first clinical event of Chagas heart disease (CHD). However, current guidelines contain no clear recommendation for early cardioverter-defibrillator implantation. Using imaging modalities, we evaluated associations among autonomic denervation, myocardial hypoperfusion, fibrosis and ventricular arrhythmia in CHD. METHODS AND RESULTS: Twenty-nine patients with CHD and preserved left ventricular function underwent 123I-metaiodobenzylguanidine (MIBG) scintigraphy, 99mTc-methoxyisobutylisonitrile (MIBI) myocardial perfusion and cardiac magnetic resonance imaging (MRI). They were divided into arrhythmic (≥ 6 ventricular premature complexes/h and/or non-sustained ventricular tachycardia on 24-hour Holter, n = 15) and non-arrhythmic (< 6 ventricular premature complexes/h and no ventricular tachycardia; n = 14) groups. The arrhythmic group had higher denervation scores from MIBG imaging (23.2 ± 18.7 vs 5.6 ± 4.9; P < .01), hypoperfusion scores from MIBI SPECT (4.7 ± 6.8 vs 0.29 ± 0.6: P = .02), innervation/perfusion mismatch scores (18.5 ± 17.5 vs 5.4 ± 4.8; P = .01) and fibrosis by late gadolinium enhancement on MRI (14.3% ± 13.5% vs 4.0% ± 2.9%; P = .04) than the non-arrhythmic group. CONCLUSION: These imaging parameters were associated with ventricular arrhythmia in early CHD and may enable risk stratification and the implementation of primary preventive strategies for SCD.
Assuntos
Cardiomiopatia Chagásica , Doença de Chagas , Doença da Artéria Coronariana , Isquemia Miocárdica , Complexos Ventriculares Prematuros , Humanos , Cardiomiopatia Chagásica/complicações , Cardiomiopatia Chagásica/diagnóstico por imagem , 3-Iodobenzilguanidina , Meios de Contraste , Gadolínio , Morte Súbita Cardíaca/prevenção & controle , Fibrose , Doença de Chagas/complicações , Doença de Chagas/diagnóstico por imagem , Denervação AutônomaRESUMO
Resumo Fundamento A ressonância magnética cardíaca (RMC) tem relevância diagnóstica crescente em sobreviventes de morte súbita cardíaca (MSC) ou arritmia ventricular instável (AVI) em países desenvolvidos. Objetivo Procuramos avaliar retrospectivamente o papel adicional da RMC em um país em desenvolvimento com poucos recursos disponíveis e que pode direcionar um uso mais eficaz desses recursos. Métodos Foram incluídos sobreviventes de MSC ou AVI admitidos entre 2009 e 2019 em uma instituição acadêmica terciária após a realização de RMC. Dados demográficos, clínicos e laboratoriais foram coletados dos prontuários. Imagens e laudos de RMC foram analisados e o impacto disso no diagnóstico etiológico final foi afirmado. Realizou-se análise descritiva e definiu-se p<0,05 como significativo. Resultados Sessenta e quatro pacientes, 54,9±15,4 anos, sendo 42 (71,9%) do sexo masculino. A maioria dos eventos (81,3%) foi extra-hospitalar e a taquicardia ventricular foi o ritmo mais comum. Medicamentos cardiovasculares foram utilizados anteriormente por 55 pacientes, sendo os betabloqueadores os medicamentos mais utilizados (37,5%). O eletrocardiograma apresentava áreas elétricas inativas em 21,9% e todos apresentavam fibrose na RMC. A média da fração de ejeção do ventrículo esquerdo (FEVE) foi de 44±14%, com 60,9% ≤50% e apenas 29,7% ≤35%. Identificou-se realce tardio com gadolínio em 71,9%, com padrão transmural em 43,8%. A miocardiopatia chagásica foi a etiologia mais comum (28,1%), seguida da miocardiopatia isquêmica (17,2%). Entre 26 sem etiologia previamente identificada, foi possível definir com RMC (15 pacientes - 57%). Conclusão De acordo com estudos anteriores em países desenvolvidos, a RMC foi capaz de aumentar o diagnóstico etiológico e identificar o substrato arritmogênico, permitindo melhor atendimento em metade dos pacientes subdiagnosticados.
Abstract Background Cardiac magnetic resonance (CMR) has an increasing diagnostic relevance in survivors of sudden cardiac death (SCD) or unstable ventricular arrhythmia (UVA) in developed countries. Objective To evaluate retrospectively the additional role of CMR in a developing country where few resources are available, and should be used more effectively. Methods The study included SCD or UVA survivors admitted between 2009 and 2019 at a tertiary academic institution referred to CMR. Demographic, clinical, and laboratory data were collected from the medical records. CMR images and reports were reviewed and their impact on the final etiological diagnosis was determined. A descriptive analysis was performed and p<0.05 established as significant. Results Sixty-four patients, 54.9±15.4 years old, and 42 (71.9%) males. Most events (81.3%) were out of the hospital and ventricular tachycardia was the most common rhythm. Cardiovascular medications were previously used by 55 patients, and beta-blockers were the most used medications (37.5%). Electrocardiogram had electrical inactive areas in 21.9% and all of them had fibrosis at CMR. Mean left ventricular ejection fraction (LVEF) was 44±14%, with 60.9% ≤50% and only 29.7% ≤35%. Late gadolinium enhancement was identified in 71.9%, with a transmural pattern in 43.8%. Chagas cardiomyopathy was the most common etiology (28.1%), followed by ischemic cardiomyopathy (17.2%). Among 26 without a previously identified etiology, CMR could define it (15 patients - 57%). Conclusion In accordance with previous studies in developed countries, CMR was capable of increasing etiological diagnosis and identifying the arrhythmogenic substrate, allowing better care in half of the underdiagnosed patients.
RESUMO
Background: New techniques for cardiac arrhythmia ablation, such as contact force (CF) technology, have emerged recently. These catheters provide information about adequate tissue contact for optimal lesions. In adults, these techniques have shown greater accuracy, reduced arrhythmia recurrence and complications, and higher success rates. However, data on pediatric patients are limited. Objective: The purpose of this study was to describe the experience with arrhythmia ablation using CF catheters in the pediatric population. Methods: A retrospective cross-sectional descriptive study of all patients <18 years old undergoing cardiac 3-dimensional mapping and ablation with CF between March 2016 and June 2022 was performed. Results: A total of 321 patients were included (51.40% male; mean age 12.26 years). The most frequent arrhythmia were supraventricular tachycardia (SVT) mediated by accessory pathways (APs) (atrioventricular reentrant tachycardia in 82.24%, ventricular arrhythmia in 11.21%, atrial tachycardia in 5.92%). Mean procedural time was 2.86 ± 1.2 hours, and average contact used was 14.33g ± 6.88g. The success rate of ablation was 97.82% with a low risk of complications. Conclusion: This is the largest published series of CF technology use in patients <18 years old. In the pediatric population, CF ablation is a safe procedure with high success rates and can be used for most arrhythmic substrates. The most frequent tachycardia observed in this study was SVT mediated by APs. Contact with 14g is safe and yields an excellent outcome in children. The presence of structural heart anomalies and previous ablation procedures decreased the success rate.
RESUMO
Un gossypiboma, oblitoma o textiloma se define como todo cuerpo extraño olvidado en el interior de un paciente durante una intervención quirúrgica. Representa una complicación posquirúrgica poco frecuente pero de consecuencias potencialmente graves. En general, se manifiesta con cuadros clínicos variables: una masa o pseudotumor, sangrados, fiebre, dolor, varios meses o años después de la cirugía original. También puede ser un hallazgo accidental. Describimos el caso clínico de una paciente con un gossypiboma vinculado a una cirugía cardíaca que se realizó 40 años antes al cuadro clínico actual, que se presenta con arritmia ventricular maligna.
A gossypiboma, oblitoma or textiloma is defined as a surgical object left in the interior of the body after surgery. It represents an uncommon but potentially life threatening post-surgery complication. Clinical manifestations are variable and depend on location, relations and size, from pseudo-tumoral masses, bleeding, fever, pain and other nonspecific presentations. The onset of symptoms is unpredictable, occurring from months or years after surgery. Patients may course asymptomatically and be diagnosed incidentally as an imaging finding. We describe a case of a patient with gossypiboma diagnosed 40 years after undergoing cardiac surgery, who presented with a malignant ventricular arrhythmia.
Um gossypiboma, oblitoma ou textiloma está definido como todo corpo estranho esquecido no interior de um paciente durante um procedimento cirúrgico, representando uma complicação pos cirúrgica pouco frequente, mas com consequências potencialmente graves. Geralmente, se manifesta com quadros clínicos variáveis: uma massa ou pseudotumor, sangramentos, febre, dor, varios meses ou anos após a cirurgia original ou ser um hachado acidental. Descrevemos o caso clínico de uma paciente com um gossypiboma vinculado a uma cirurgia cardíaca realizada 40 anos antes do quadro clínico atual, que se apresenta com arritmia ventricular maligna.
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Arritmias Cardíacas/etiologia , Tampões de Gaze Cirúrgicos , Corpos Estranhos/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Cirurgia Torácica , Corpos Estranhos/cirurgiaRESUMO
RESUMEN Introducción: La muerte súbita cardíaca no ha disminuido de igual manera que la mortalidad por enfermedad coronaria, por la elevada incidencia de las paradas cardíacas súbitas (PCS). Objetivos: Determinar factores predictivos de PCS por arritmia ventricular en pacientes con infarto agudo de miocardio. Método: Se realizó un estudio analítico en el Servicio de Cardiología de Las Tunas entre 2011 y 2017. La población de estudio estuvo conformada por los 917 pacientes ingresados con infarto agudo de miocardio. Los 90 pacientes con PCS en arritmia ventricular constituyeron el «grupo de casos¼; el resto fue el «grupo control¼. Se utilizó estadística descriptiva y un modelo de regresión logística múltiple, y se calculó el índice de probabilidad (odds ratio [OR]), con un 95% de confiabilidad para determinar los factores predictivos. Resultados: En los pacientes del grupo de casos predominó el sexo masculino (73%), el infarto biventricular (24,7%), la fracción de eyección ventricular izquierda (FEVI) <35% (18,9%) y los fallecidos (41,1%) en relación al grupo control. Al 10,0% se le administró betabloqueadores en la primera asistencia médica. El shock cardiogénico (OR=15,3), la FEVI <35% (OR=8,51), la creatina quinasa > 1200 UI (OR=2,77), la obesidad (OR=3,16), el hábito de fumar (OR=2,28), el supra/infradesnivel del ST en el electrocardiograma >15 mm (OR=2,23) y el infarto anterior (OR=2,39) se asociaron a la PCS en arritmia ventricular. Conclusiones: El shock cardiogénico, la FEVI <35%, la creatina quinasa >1200 UI, la obesidad, el hábito de fumar, el supra/infradesnivel del ST en el electrocardiograma >15 mm y el infarto anterior fueron factores predictivos de PCS en arritmia ventricular.
ABSTRACT Introduction: Sudden cardiac death has not decreased in the same way as mortality due to coronary heart disease, because of the high incidence of sudden cardiac arrest (SCA). Objectives: To determine predictive factors of SCA due to ventricular arrhythmia in patients with acute myocardial infarction. Method: An analytical study was carried out in the Cardiology Department of Las Tunas between 2011 and 2017. The population of study was 917 patients admitted with acute myocardial infarction. All 90 patients with SCA in ventricular arrhythmia represented the "case group"; the rest were the "control group". Descriptive statistics were used, as well as a multiple logistic regression model; the odds ratios (OR) was calculated, with 95% reliability to determine the predictive factors. Results: In the patients of the case group predominated: male sex (73%), biventricular infarction (24.7%), left ventricular ejection fraction (LVEF) <35% (18.9%) and deceased (41.1%); all these results compared to the control group. A 10.0% was given beta-blockers on their first medical assistance. Cardiogenic shock (OR 15.3), LVEF <35% (OR 8.51), creatine kinase >1200 IU (OR 2.77), obesity (OR 3.16), smoking (OR 2.28), ST-segment elevation/depression on the electrocardiogram >15 mm (OR 2.23) and anterior wall infarction (OR 2.39) were associated with SCA due to ventricular arrhythmia. Conclusions: Cardiogenic shock, LVEF <35%, creatine kinase > 1200 IU, obesity, smoking, ST-segment elevation/depression on the electrocardiogram >15 mm and anterior wall infarction were predictive factors of SCA due to ventricular arrhythmia.
Assuntos
Arritmias Cardíacas , Fatores de Risco , Morte Súbita Cardíaca , Parada Cardíaca , Infarto do MiocárdioRESUMO
Resumen Se presenta un caso clínico de una mujer gestante que presentó bloqueo atrioventricular completo en labor de parto, bradicardia severa, intervalo QT prolongado secundario, torsión de puntas y paro cardiorrespiratorio, del cual fue recuperada. Se discuten los mecanismos potenciales que pueden desencadenar este escenario.
Abstract A clinical case of a pregnant woman who presented with complete atrioventricular block in labor, severe bradycardia, secondary prolonged QT interval, Torsades de pointes and aborted cardiorespiratory arrest is presented. Potential mechanisms that can trigger this scenario are discussed.
Assuntos
Humanos , Feminino , Adulto , Trabalho de Parto , Gravidez , Taquicardia Ventricular , Costa Rica , Morte Súbita , Parto , Bloqueio AtrioventricularRESUMO
La sarcoidosis es una enfermedad inflamatoria crónica que posee una amplia variabilidad de presentaciones clínicas. El compromiso cardíaco de esta patología oscila en el orden del 5%, pudiendo variar desde anormalidades en la conducción hasta la falla cardíaca. Existe poco conocimiento sobre los beneficios de su tratamiento y no hay datos que evalúen la reducción de la mortalidad a largo plazo, por lo que genera este tipo de pacientes un gran desafío para el profesional. A continuación presentamos el caso de un masculino de 37 años con taquicardia ventricular como debut cardiológico de una sarcoidosis.
Assuntos
Arritmias Cardíacas , Sarcoidose , Insuficiência CardíacaRESUMO
RESUMEN Se presenta una panorámica de la falla cardíaca ligada a las arritmias y a la muerte súbita, que pueden coexistir, agravarse, o ser causa o consecuencia una de otra. Se discuten los signos eléctricos premonitorios que permiten estratificar riesgo en pacientes con eventos previos, con posible acercamiento a la realidad, y en quienes no los han presentado (la mayoría, los no protegidos), y resulta muy difícil o imposible establecer un pronóstico. Estos signos son numerosos, esquivos, de baja especificidad y sensibilidad, ninguno es absoluto ni despreciable, para interpretarlos se requiere una visión integral. Se discuten las extrasístoles ventriculares como predictoras y desencadenantes de arritmias, de muerte súbita y de miocardiopatía, y la utilidad de los procedimientos ablativos frente a los medicamentosos. Los signos eléctricos son buenos para identificar grandes grupos de riesgo pero no lo son tanto para, dentro del gran grupo de bajo riesgo (la mayoría), identificar los individuos de alto riesgo.
ABSTRACT In this research is presented an overview of heart failure related to arrhythmias and sudden death, which can coexist, worsen, or be cause or consequence of one another. Here are discussed the premonitory electrical signs that allow to stratify risk in patients with previous events, with a possible approach to reality, and in those who have not presented them (most of them, the unprotected ones) and where a prognosis is very difficult, or impossible, to be established. These signs are numerous, elusive, with low specificity and sensitivity, none is absolute or negligible, in order to interpret them, a comprehensive vision is required. Premature ventricular contractions are discussed as predictors and triggers of arrhythmias, sudden death and cardiomyopathy, as well as the usefulness of ablative procedures versus medications. Electrical signs are good for identifying large risk groups but not for identifying high risk individuals inside the large low risk group (the majority).
Assuntos
Insuficiência Cardíaca , Arritmias Cardíacas , Complexos Ventriculares Prematuros , Morte SúbitaRESUMO
BACKGROUND: Catheter ablation of ventricular arrhythmias (VAs) arising from the left ventricular Summit (LVS) is challenging and requires high-dose fluoroscopy to limit vascular damage of the coronary arteries. Ionizing radiation can increase the incidence of malignancies to both patient and operator. This study describes outcomes of catheter ablation of LVS VAs using intracardiac echo-facilitated 3D electroanatomical mapping (ICE-3D) to avoid fluoroscopy. METHODS: Twenty-six patients (47 ± 17 years old; 52% males; median ejection fraction 55 ± 13%) with premature ventricular contractions or ventricular tachycardia underwent catheter ablation. VAs were localized using ICE-3D with arrhythmia foci being mapped at the LVS. Focal ablation was performed using a 3.5-mm open-irrigated, contact force sensing radiofrequency catheter. RESULTS: Acute success and recurrence rates were 84% and 24%, respectively. Holter burden was significantly reduced (24 ± 15% to 1.5 ± 2%; P = 0.01) after ablation. The use of zero fluoroscopy was achieved in 100% of cases. No major complications were observed. CONCLUSIONS: Zero fluoroscopy catheter ablation of LVS VAs using ICE-3D mapping is feasible and effective.
Assuntos
Ablação por Cateter , Ecocardiografia , Mapeamento Epicárdico/métodos , Taquicardia Ventricular/cirurgia , Complexos Ventriculares Prematuros/cirurgia , Teste de Esforço , Feminino , Fluoroscopia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Taquicardia Ventricular/diagnóstico por imagem , Complexos Ventriculares Prematuros/diagnóstico por imagemRESUMO
Objetivo: Establecer una comparación en las mediciones de calidad de vida relacionada con la salud y carga de los síntomas con el ASTA en pacientes con arritmia ventricular, antes y después de implante de cardiodesfibrilador. Método: observacional analítico, con diseño de serie de casos y de abordaje cuantitativo. Participaron 83 pacientes, con diagnóstico de arritmia ventricular de dos instituciones de la ciudad de Bucaramanga, con dos mediciones, antes y después de implante de cardiodesfibrilador. Instrumento: Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia (ASTA), versión validada al español. Análisis: se utilizó estadística descriptiva y para determinar el cambio en los puntajes de las mediciones iniciales y finales, se utilizó, la prueba pareada de T Student. Resultados: los pacientes con arritmia ventricular que recibieron implante de cardiodesfibrilador, son en su mayoría hombres con una media de edad de 60,97 años, de estratos socioeconómicos bajos, ocupación hogar y labores agrícolas, el puntaje en la escala de calidad de vida inicial fue de 10.97 y de 9.52 para la medición final post-implante, con un valor de p: 0.001, para la comparación entre los dos puntajes, lo que muestra una diferencia estadísticamente significativa. Conclusión: la evaluación de la calidad de vida del paciente con arritmia ventricular medida por un instrumento especifico, muestra una afectación de la calidad de vida, con una leve mejoría en la medición a un mes posterior al implante del cardiodesfibrilador y visualiza la importancia de intervenciones de Enfermería en etapas tempranas del pre-implante en diferentes aspectos.
Objective: To establish a comparison in health-related quality of life measurements and symptoms burden with ASTA in patients with ventricular arrhythmia, before and after implantation of a cardiodefibrillator. Method: observational analytical, with case series design, with a quantitative approach. A total of 83 patients participated, with a diagnosis of ventricular arrhythmia from two institutions in the city of Bucaramanga, with two measurements, before and after implantation of a cardiodefibrillator. Instrument, Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia (ASTA), version validated in Spanish. Analysis: descriptive statistics were used and, to determine the change in the scores of the initial and final measurements, the paired test of T -Student was used. Results: patients with ventricular arrhythmia, and who received a cardio-defibrillator implant, are mostly men, with a mean age of 60.97 years, from low socioeconomic strata, household occupation and agricultural work, the score in the quality scale of initial life was of 10.97 and of 9.52 for the final measurement after implant, with a value of p: 0.001, for the comparison between the two scores, which shows a statistically significant difference. Conclusion: the evaluation of the quality of life of the patient with ventricular arrhythmia, measured by a specific instrument, shows an affectation of the quality of life, with a slight improvement in the measurement one month after the implantation of the cardiodefibrillator. And the importance of nursing interventions in the early stages of pre-implantation in different aspects is visualized.
Assuntos
Humanos , Masculino , Feminino , Qualidade de Vida , Taquicardia Ventricular , Enfermagem , Desfibriladores ImplantáveisRESUMO
The aim of the present study was to assess heart rate variability (HRV) in Boxer dogs affected by arrhythmogenic right ventricular cardiomyopathy (ARVC). Fourteen Boxer dogs classified as affected and 28 classified as unaffected were included in a prospective case-control study. Dogs underwent 24-hour ambulatory ECG and were classified as affected (>1,000 VPCs/24 hours) or unaffected (<20 VPCs/24 hours) by ARVC based on the number of ventricular arrhythmias. HRV was assessed using 24-h Holter ECG monitoring; the studied parameters were SDNN, SDANN, SDNNIDX, rMSSD and pNN50. Data were submitted to logarithmic transformation and HRV parameters were compared between groups and correlated according to the disease status, number and severity of ventricular arrhythmias using Students t test, linear regression and Spearmans test. There was no interaction between the HRV parameters and the number and severity of ventricular arrhythmias. SDNNlog (2.35±0.14 vs. 2.46±0.12, P=0.01), SDNNIDXlog (2.18±0.14 vs. 2.24±0.10, P=0.002) and pNN50log (1.47±0.19 vs. 1.64±0.13, P=0.002) were significantly lower in the affected group compared with the unaffected. According to this study, HRV are different in a population of Boxers dogs affected by ARVC compared to a population of unaffected dogs, and these differences are not consequences of low cardiac output caused by ventricular arrhythmias since animals that had higher number and complexity of arrhythmias were not those who had lower values of HRV.
O objetivo do presente estudo foi avaliar a variabilidade da frequência cardíaca (VFC) em cães da raça Boxer acometidos pela cardiomiopatia arritmogênica do ventrículo direito (CAVD). Para isso, foram incluídos, em estudo prospectivo caso-controle, 14 cães classificados como acometidos pela CAVD e 28 classificados como não acometidos. Os cães foram submetidos à eletrocardiografia ambulatorial de 24 horas e então classificados como acometidos (quando apresentaram mais de 1.000 complexos ventriculares prematuros em 24 horas) ou não acometidos (quando apresentaram menos de 20 complexos ventriculares prematuros em 24 horas) pela CAVD, com base no número de arritmias ventriculares. A VFC foi avaliada mediante monitoramento Holter de 24 horas. Os parâmetros estudados foram SDNN, SDANN, SDNNIDX, rMSSD e pNN50. Os dados foram submetidos à transformação logarítmica e os parâmetros da VFC foram comparados e correlacionados de acordo com a presença ou não da doença, número e severidade das arritmias pelo teste t de Student, regressão linear e teste de Spearman. Não houve interação entre as variáveis da VFC e o número e a severidade das arritmias ventriculares. Porém, as variáveis SDNNlog (2,35±0,14 vs. 2,46±0,12, P=0,01), SDNNIDXlog (2,18±0,14 vs. 2,24±0,10, P=0.002) e pNN50log (1,47±0,19 vs. 1,64±0,13, P=0,002) foram significativamente menores no grupo de animais acometidos pela doença. De acordo com os resultados do presente estudo, a VFC é menor nos Boxers acometidos pela CAVD em relação aos cães não acometidos, e essa diferença não pode ser atribuída ao baixo débito cardíaco, supostamente causado pelas arritmias ventriculares, uma vez que os animais que apresentaram maior número e complexidade das arritmias não foram os que apresentaram os menores valores da VFC.
Assuntos
Animais , Cães , Arritmias Cardíacas/veterinária , Displasia Arritmogênica Ventricular Direita/veterinária , Frequência Cardíaca , Eletrocardiografia Ambulatorial/veterinária , Sistema Nervoso Autônomo/fisiologiaRESUMO
The aim of the present study was to assess heart rate variability (HRV) in Boxer dogs affected by arrhythmogenic right ventricular cardiomyopathy (ARVC). Fourteen Boxer dogs classified as affected and 28 classified as unaffected were included in a prospective case-control study. Dogs underwent 24-hour ambulatory ECG and were classified as affected (>1,000 VPCs/24 hours) or unaffected (<20 VPCs/24 hours) by ARVC based on the number of ventricular arrhythmias. HRV was assessed using 24-h Holter ECG monitoring; the studied parameters were SDNN, SDANN, SDNNIDX, rMSSD and pNN50. Data were submitted to logarithmic transformation and HRV parameters were compared between groups and correlated according to the disease status, number and severity of ventricular arrhythmias using Students t test, linear regression and Spearmans test. There was no interaction between the HRV parameters and the number and severity of ventricular arrhythmias. SDNNlog (2.35±0.14 vs. 2.46±0.12, P=0.01), SDNNIDXlog (2.18±0.14 vs. 2.24±0.10, P=0.002) and pNN50log (1.47±0.19 vs. 1.64±0.13, P=0.002) were significantly lower in the affected group compared with the unaffected. According to this study, HRV are different in a population of Boxers dogs affected by ARVC compared to a population of unaffected dogs, and these differences are not consequences of low cardiac output caused by ventricular arrhythmias since animals that had higher number and complexity of arrhythmias were not those who had lower values of HRV.(AU)
O objetivo do presente estudo foi avaliar a variabilidade da frequência cardíaca (VFC) em cães da raça Boxer acometidos pela cardiomiopatia arritmogênica do ventrículo direito (CAVD). Para isso, foram incluídos, em estudo prospectivo caso-controle, 14 cães classificados como acometidos pela CAVD e 28 classificados como não acometidos. Os cães foram submetidos à eletrocardiografia ambulatorial de 24 horas e então classificados como acometidos (quando apresentaram mais de 1.000 complexos ventriculares prematuros em 24 horas) ou não acometidos (quando apresentaram menos de 20 complexos ventriculares prematuros em 24 horas) pela CAVD, com base no número de arritmias ventriculares. A VFC foi avaliada mediante monitoramento Holter de 24 horas. Os parâmetros estudados foram SDNN, SDANN, SDNNIDX, rMSSD e pNN50. Os dados foram submetidos à transformação logarítmica e os parâmetros da VFC foram comparados e correlacionados de acordo com a presença ou não da doença, número e severidade das arritmias pelo teste t de Student, regressão linear e teste de Spearman. Não houve interação entre as variáveis da VFC e o número e a severidade das arritmias ventriculares. Porém, as variáveis SDNNlog (2,35±0,14 vs. 2,46±0,12, P=0,01), SDNNIDXlog (2,18±0,14 vs. 2,24±0,10, P=0.002) e pNN50log (1,47±0,19 vs. 1,64±0,13, P=0,002) foram significativamente menores no grupo de animais acometidos pela doença. De acordo com os resultados do presente estudo, a VFC é menor nos Boxers acometidos pela CAVD em relação aos cães não acometidos, e essa diferença não pode ser atribuída ao baixo débito cardíaco, supostamente causado pelas arritmias ventriculares, uma vez que os animais que apresentaram maior número e complexidade das arritmias não foram os que apresentaram os menores valores da VFC.(AU)
Assuntos
Animais , Cães , Frequência Cardíaca , Displasia Arritmogênica Ventricular Direita/veterinária , Arritmias Cardíacas/veterinária , Eletrocardiografia Ambulatorial/veterinária , Sistema Nervoso Autônomo/fisiologiaRESUMO
A wide spectrum of cardiac arrhythmias has been observed in patients with isolated ventricular non-compaction, which is defined by hypertrabeculated ventricular myocardium with deep intertrabecular recesses, in the absence of concomitant congenital heart disease. In this genetically diverse phenotype, the development of fibrosis contributes to an arrhythmogenic substrate underlying atrioventricular conduction diseases, supraventricular tachycardias and ventricular tachycardias. Within this spectrum, monomorphic ventricular tachycardia is the most frequently observed arrhythmia, and this prevalence has important implications for sudden cardiac death risk.
RESUMO
ABSTRACT: The aim of the present study was to assess heart rate variability (HRV) in Boxer dogs affected by arrhythmogenic right ventricular cardiomyopathy (ARVC). Fourteen Boxer dogs classified as affected and 28 classified as unaffected were included in a prospective case-control study. Dogs underwent 24-hour ambulatory ECG and were classified as affected (>1,000 VPCs/24 hours) or unaffected ( 20 VPCs/24 hours) by ARVC based on the number of ventricular arrhythmias. HRV was assessed using 24-h Holter ECG monitoring; the studied parameters were SDNN, SDANN, SDNNIDX, rMSSD and pNN50. Data were submitted to logarithmic transformation and HRV parameters were compared between groups and correlated according to the disease status, number and severity of ventricular arrhythmias using Students t test, linear regression and Spearmans test. There was no interaction between the HRV parameters and the number and severity of ventricular arrhythmias. SDNNlog (2.35±0.14 vs. 2.46±0.12, P=0.01), SDNNIDXlog (2.18±0.14 vs. 2.24±0.10, P=0.002) and pNN50log (1.47±0.19 vs. 1.64±0.13, P=0.002) were significantly lower in the affected group compared with the unaffected. According to this study, HRV are different in a population of Boxers dogs affected by ARVC compared to a population of unaffected dogs, and these differences are not consequences of low cardiac output caused by ventricular arrhythmias since animals that had higher number and complexity of arrhythmias were not those who had lower values of HRV.
RESUMO: O objetivo do presente estudo foi avaliar a variabilidade da frequência cardíaca (VFC) em cães da raça Boxer acometidos pela cardiomiopatia arritmogênica do ventrículo direito (CAVD). Para isso, foram incluídos, em estudo prospectivo caso-controle, 14 cães classificados como acometidos pela CAVD e 28 classificados como não acometidos. Os cães foram submetidos à eletrocardiografia ambulatorial de 24 horas e então classificados como acometidos (quando apresentaram mais de 1.000 complexos ventriculares prematuros em 24 horas) ou não acometidos (quando apresentaram menos de 20 complexos ventriculares prematuros em 24 horas) pela CAVD, com base no número de arritmias ventriculares. A VFC foi avaliada mediante monitoramento Holter de 24 horas. Os parâmetros estudados foram SDNN, SDANN, SDNNIDX, rMSSD e pNN50. Os dados foram submetidos à transformação logarítmica e os parâmetros da VFC foram comparados e correlacionados de acordo com a presença ou não da doença, número e severidade das arritmias pelo teste t de Student, regressão linear e teste de Spearman. Não houve interação entre as variáveis da VFC e o número e a severidade das arritmias ventriculares. Porém, as variáveis SDNNlog (2,35±0,14 vs. 2,46±0,12, P=0,01), SDNNIDXlog (2,18±0,14 vs. 2,24±0,10, P=0.002) e pNN50log (1,47±0,19 vs. 1,64±0,13, P=0,002) foram significativamente menores no grupo de animais acometidos pela doença. De acordo com os resultados do presente estudo, a VFC é menor nos Boxers acometidos pela CAVD em relação aos cães não acometidos, e essa diferença não pode ser atribuída ao baixo débito cardíaco, supostamente causado pelas arritmias ventriculares, uma vez que os animais que apresentaram maior número e complexidade das arritmias não foram os que apresentaram os menores valores da VFC.
RESUMO
ABSTRACT: The aim of the present study was to assess heart rate variability (HRV) in Boxer dogs affected by arrhythmogenic right ventricular cardiomyopathy (ARVC). Fourteen Boxer dogs classified as affected and 28 classified as unaffected were included in a prospective case-control study. Dogs underwent 24-hour ambulatory ECG and were classified as affected (>1,000 VPCs/24 hours) or unaffected (<20 VPCs/24 hours) by ARVC based on the number of ventricular arrhythmias. HRV was assessed using 24-h Holter ECG monitoring; the studied parameters were SDNN, SDANN, SDNNIDX, rMSSD and pNN50. Data were submitted to logarithmic transformation and HRV parameters were compared between groups and correlated according to the disease status, number and severity of ventricular arrhythmias using Student’s t test, linear regression and Spearman’s test. There was no interaction between the HRV parameters and the number and severity of ventricular arrhythmias. SDNNlog (2.35±0.14 vs. 2.46±0.12, P=0.01), SDNNIDXlog (2.18±0.14 vs. 2.24±0.10, P=0.002) and pNN50log (1.47±0.19 vs. 1.64±0.13, P=0.002) were significantly lower in the affected group compared with the unaffected. According to this study, HRV are different in a population of Boxers dogs affected by ARVC compared to a population of unaffected dogs, and these differences are not consequences of low cardiac output caused by ventricular arrhythmias since animals that had higher number and complexity of arrhythmias were not those who had lower values of HRV.
RESUMO: O objetivo do presente estudo foi avaliar a variabilidade da frequência cardíaca (VFC) em cães da raça Boxer acometidos pela cardiomiopatia arritmogênica do ventrículo direito (CAVD). Para isso, foram incluídos, em estudo prospectivo caso-controle, 14 cães classificados como acometidos pela CAVD e 28 classificados como não acometidos. Os cães foram submetidos à eletrocardiografia ambulatorial de 24 horas e então classificados como acometidos (quando apresentaram mais de 1.000 complexos ventriculares prematuros em 24 horas) ou não acometidos (quando apresentaram menos de 20 complexos ventriculares prematuros em 24 horas) pela CAVD, com base no número de arritmias ventriculares. A VFC foi avaliada mediante monitoramento Holter de 24 horas. Os parâmetros estudados foram SDNN, SDANN, SDNNIDX, rMSSD e pNN50. Os dados foram submetidos à transformação logarítmica e os parâmetros da VFC foram comparados e correlacionados de acordo com a presença ou não da doença, número e severidade das arritmias pelo teste t de Student, regressão linear e teste de Spearman. Não houve interação entre as variáveis da VFC e o número e a severidade das arritmias ventriculares. Porém, as variáveis SDNNlog (2,35±0,14 vs. 2,46±0,12, P=0,01), SDNNIDXlog (2,18±0,14 vs. 2,24±0,10, P=0.002) e pNN50log (1,47±0,19 vs. 1,64±0,13, P=0,002) foram significativamente menores no grupo de animais acometidos pela doença. De acordo com os resultados do presente estudo, a VFC é menor nos Boxers acometidos pela CAVD em relação aos cães não acometidos, e essa diferença não pode ser atribuída ao baixo débito cardíaco, supostamente causado pelas arritmias ventriculares, uma vez que os animais que apresentaram maior número e complexidade das arritmias não foram os que apresentaram os menores valores da VFC.
RESUMO
BACKGROUND/AIMS: Ventricular arrhythmia is associated with increased risk of cardiovascular events and death in the general population. Sudden death is a leading cause of death in end-stage renal disease. We aimed at evaluating the effects of ventricular arrhythmia on clinical outcomes in patients with earlier stages of chronic kidney disease (CKD). METHODS: In a prospective study of 109 nondialyzed CKD patients (estimated glomerular filtration rate 34.8 ± 16.1 ml/min/1.73 m2, 57 ± 11.4 years, 61% male, 24% diabetics), we tested the hypothesis that the presence of subclinical complex ventricular arrhythmia, assessed by 24-hour electrocardiogram, is associated with increased risks of cardiovascular events, hospitalization, and death and with their composite outcome during 24 months of follow-up. Complex ventricular arrhythmia was defined as the presence of multifocal ventricular extrasystoles, paired ventricular extrasystoles, nonsustained ventricular tachycardia, or R wave over T wave. RESULTS: We identified complex ventricular arrhythmia in 14% of participants at baseline. During follow-up, 11 cardiovascular events, 15 hospitalizations, and 4 deaths occurred. The presence of complex ventricular arrhythmia was associated with cardiovascular events (p < 0.001), hospitalization (p = 0.018), mortality (p < 0.001), and the composite outcome (p < 0.001). In multivariate Cox regression analysis, adjusting for demographic characteristics, complex ventricular arrhythmia was associated with increased risk of the composite outcome (HR 4.40; 95% CI 1.60-12.12; p = 0.004). CONCLUSION: In this pilot study, the presence of asymptomatic complex ventricular arrhythmia was associated with poor clinical outcomes in nondialyzed CKD patients.
RESUMO
OBJECTIVES: To evaluate the use of ondansetron in a tertiary care pediatric health system, assess the incidence of ventricular tachyarrhythmia within 24 hours of ondansetron, and identify the characteristics of children experiencing a ventricular tachyarrhythmia after ondansetron, to identify potential risk factors. STUDY DESIGN: This retrospective chart review identified children ≤18 years of age who received ondansetron within 24 hours prior to a ventricular tachyarrhythmia. Those identified were evaluated for other diagnoses, concomitant medication use, electrolyte abnormalities, or underlying conduction abnormalities that may have contributed to the arrhythmia. RESULTS: A total of 199 773 doses of ondansetron were administered to 37 794 patients over 58 009 visits. Average dose was 0.13 mg/kg/dose (range 0.005-0.86 mg/kg/dose). Seven patients received ondansetron within 24 hours prior to a ventricular arrhythmia. All 7 patients had underlying congenital cardiac conduction abnormalities (n = 3) or other major cardiac diagnoses (n = 4). In clinical review, torsades de pointes was found in only 1 of the 7 patients. CONCLUSIONS: This retrospective study found the risk of ventricular arrhythmia within 24 hours after ondansetron administration was 3 in 100 000 patients treated annually (0.003%). Children with major cardiac conditions could be considered for electrocardiogram screening and continuous cardiac monitoring while receiving ondansetron. Our findings do not support recommendations for electrocardiogram screening or continuous monitoring of other pediatric populations receiving ondansetron.
Assuntos
Ondansetron/efeitos adversos , Taquicardia Ventricular/induzido quimicamente , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Lactente , Masculino , Estudos Retrospectivos , Medição de Risco , Taquicardia Ventricular/epidemiologiaRESUMO
BACKGROUND: Chagas disease (ChD) may lead to life-threatening heart disease, including malignant ventricular arrhythmias. The use of implantable cardioverter defibrillators (ICDs) has become the main therapeutic strategy for secondary prevention of SCD in Chagas disease (ChD). Microvolt T-wave alternans (MTWA) is a direct measure of ventricular repolarization instability and has emerged as a potentially useful way of determining arrhythmia vulnerability. However, this methodology has not been evaluated in patients with ChD. OBJECTIVE: To evaluate the predictive value of MTWA testing for appropriate therapy or death in ChD patients with ICDs. METHODS: This prospective study included consecutive patients who received ICD implantations in a Brazilian tertiary referral center. RESULTS: Seventy-two patients were followed for a median time of 422 (range 294-642) days. Thirty-three patients had ChD. The MTWA was non-negative (positive or indeterminate) in 27 (81.8%) of ChD patients. The combined primary outcome (appropriate ICD therapy or death) occurred in 29 patients (40.3%); 17 out 33 ChD patients presented the primary outcome. There was a statistically significant difference in event-free survival between ChD patients with negative and non-negative MTWA results (p=0.02). Non-negative MTWA tests nearly triple the risk of appropriate ICD therapy or death (HR=2.7, 95% CI: 1.7-4.4, p=0.01) in patients with ChD and was the only variable associated with outcomes. The sensitivity and the negative predictive value was 100% in ChD patients. CONCLUSIONS: MTWA may be useful in recognizing high-risk ICD patients who may require adjunctive therapies with antiarrhythmic drugs or catheter ablation.