الموضوعات
Aged, 80 and over , Female , Humans , Atrial Fibrillation , Coronary Artery Disease , Heart Arrest , Upper Extremity/blood supply , Venous Thrombosis , Atrial Fibrillation/pathology , Atrial Fibrillation/physiopathology , Chronic Disease , Coronary Artery Disease/pathology , Coronary Artery Disease/physiopathology , Electrocardiography , Fatal Outcome , Heart Arrest/pathology , Heart Arrest/physiopathology , Myocardium/pathology , Venous Thrombosis/pathology , Venous Thrombosis/physiopathologyالملخص
FUNDAMENTO: O sistema de mapeamento eletro anatômico Ensite Navx é muito usado na ablação por radiofrequência (RF) da fibrilação atrial, ajudando na confecção de lesões lineares. Contudo, a correspondência da linha virtual criada pelo Ensite com a lesão patológica ainda não foi avaliada. OBJETIVO: Avaliar a continuidade da linha virtual criada pelo Ensite em modelo suíno. MÉTODOS: Realizamos ablação linear por RF (cateter de 8 mm e irrigado) em ambos os átrios de 14 suínos (35 kg) guiada pelo EnSite. Os animais foram sacrificados 14 dias pós-ablação para análise macroscópica e histológica. RESULTADOS: Foram confeccionadas 23 lesões lineares em átrio direito e 21 em átrio esquerdo dos 14 animais. A potência, temperatura e impedância médias das aplicações foram de 56 W, 54 ºC e 231 Ω para o cateter de 8mm, e de 39 W, 37 ºC e 194 Ω para o cateter irrigado. Todas (100%) as linhas foram identificadas nas faces epicárdica e endocárdica, denotando transmuralidade. À macroscopia, as lesões eram extensas e pálidas, com 3,61 cm de comprimento e 0,71 cm de profundidade e contínuas. A transmuralidade das lesões foi confirmada pela microscopia. Houve correspondência na localização das linhas do mapa virtual com as da peça anatômica em 21 das 23 (91,3%) das linhas do átrio direito e 19/21 (90,4%) do átrio esquerdo. CONCLUSÃO: Nesse modelo, as linhas criadas no mapa virtual pelo sistema EnSiteNavX se correlacionam a lesões lineares transmurais contínuas na peça anatômica, sugerindo que esse método é adequado para a ablação linear da fibrilação atrial.
BACKGROUND: EnSiteNavx electroanatomic mapping system is widely used in radiofrequency (RF) atrial fibrillation ablation, helping the creation of linear lesions. However, the correspondence of the virtual line created by EnSite with the pathological lesion has not yet been evaluated. OBJECTIVE: to assess the continuousness of Ensite-guided virtual lines in a swine model. METHODS: we performed RF ablation linear lesions (8mm and irrigated catheters tips) in both atria of 14 pigs (35Kg) guided by the EnSite. The animals were sacrificed 14 days post-ablation for macroscopic and histological analysis. RESULTS: a total of 23 lines in the right atrium and 21 lines in the left atrium were created in 14 animals. The medium power, impedance and temperature applications were 56 W, 54 ºC and 231 Ω for the 8mm tip, and 39W, 37ºC, 194 Ω for the irrigated tip catheter, respectively. All (100%) lines were identified on the epicardial and endocardial surfaces, denoting transmurality. At macroscopic examination, lesions were extensive and pale, continuous, with 3.61 cm long and 0.71 cm deep. The transmurality of the lesions was confirmed by microscopy. There was a correlation in the location of the lines at the virtual map and the anatomical lesions in 21 of 23 (91.3%) of the right atrium and 19/21 (90.4%) of the left atrium. CONCLUSION: In this model, the lines created in the virtual map by EnSiteNavX system correspond to continuous transmural linear lesions in anatomical specimen, suggesting that this method is suitable for linear ablation of atrial fibrillation.
الموضوعات
Animals , Atrial Fibrillation/surgery , Catheter Ablation/instrumentation , Atrial Fibrillation/pathology , Catheter Ablation/methods , Electric Impedance , Reference Values , Reproducibility of Results , Swine , Time Factors , User-Computer Interfaceالملخص
BACKGROUND: Atrial fibrillation is the most common significant cardiac arrhythmia in clinical practice, but its risk factors remain to be clarified. We have hypothesized that left ventricular posterior wall thickness is an independent risk factor for paroxysmal atrial fibrillation (PAF). METHODS: A total of 166 consecutive patients with paroxysmal atrial fibrillation were included in this study. Another 166 healthy check-up people, strictly age and sex-matched, were enrolled as controls in the same period. Univariable analysis and multivariable conditional logistic stepwise regression analysis were conducted. Receiver operating characteristic (ROC) curve analysis was performed on those significant indices obtained from the multivariable logistic regression analysis. RESULTS: The multivariable stepwise analysis identified left ventricular posterior wall thickness, left atrial diameter, tricuspid insufficiency and residence (countryside) as independent predictors for paroxysmal atrial fibrillation. Receiver operating characteristic curve analysis demonstrated the cut-off values of those risk factors aforementioned. CONCLUSIONS: In this strictly age and sex-matched population-based sample, left ventricular posterior wall thickness, left atrial diameter, tricuspid insufficiency and residence were predictive risks for paroxysmal atrial fibrillation. This study offers novel information therapeutically beyond that provided by traditional clinical atrial fibrillation risk factors.
ANTECEDENTES: La fibrilación atrial o auricular, es la arritmia cardíaca significativa más común en la práctica clínica, pero sigue siendo aún necesario poner en claro sus factores de riesgo. El presente trabajo asume la hipótesis de que el grosor de la pared posterior ventricular izquierda constituye un factor de riesgo independiente para la fibrilación atrial paroxística (FAP). MÉTODOS: El estudio abarca un total de 166 pacientes consecutivos con fibrilación atrial paroxística. Otras 166 personas saludables según el reconocimiento médico, pareadas estrictamente por edad y sexo, fueron registradas como controles en el mismo periodo. Se llevó a cabo un análisis de regresión logística condicional multivariante paso a paso y un análisis univariante. El análisis de la curva característica de la operación del receptor (ROC) se realizó sobre los índices significativos obtenidos a partir del análisis de regresión logística multivariante. RESULTADOS: El análisis multivariante paso a paso identificó el grosor de la pared posterior ventricular izquierda, el diámetro atrial izquierdo, la insuficiencia tricúspide y la residencia (el campo) como predictores independientes de la fibrilación atrial paroxística. El análisis de la curva característica de la operación del receptor demostró los valores límites de los factores de riesgo mencionados arriba. CONCLUSIONES: En esta muestra basada estrictamente en una población pareada por edad y género, el grosor de la pared posterior ventricular izquierda, el diámetro atrial izquierdo, la insuficiencia tricús-pide y la residencia, fueron riesgos predictivos de la fibrilación atrial paroxística. Este estudio ofrece información novedosa, terapéuticamente más allá de la proporcionada por los factores de riesgo clínicos tradicionales de la fibrilación atrial.
الموضوعات
Aged , Female , Humans , Male , Middle Aged , Atrial Fibrillation/pathology , Heart Ventricles/pathology , Tricuspid Valve/pathology , Chi-Square Distribution , China , Logistic Models , ROC Curve , Risk Factorsالملخص
La fibrilación auricular que acompaña a la cardiopatíachagásica crónica constituye un mal pronóstico, dada suasociación con la grave disfunción sistólica ventricularizquierda y la formación de trombos auriculares con tendenciaa la embolización sistémica. Se analizó la fibrilaciónauricular en pacientes chagásicos de la zona norte del estado Anzoátegui. Se estableció la relación de la fibrilación auricularcon eventos cardíacos mayores como la enfermedad vascularcerebral, la muerte cardiovascular y la hospitalizaciónpor causas cardíacas no planificadas. 98 pacientes chagásicos 56 sexo masculino y 42 sexo femenino, con edad promedio de 63,56 años fueron clasificados en losgrupos sero-positivo Ch I (electrocardiograma normal), Ch II(electrocardiograma anormal) y Ch III (electrocardiogramaanormal e insuficiencia cardíaca) y evaluados por tres años consecutivos para determinar la prevalencia de fibrilación auricular y su asociación con los eventos cardíacos mayores. La prevalencia de fibrilación auricular en la totalidad de los pacientes chagásicos fue 22,84 ± 2,76%, con una mayor frecuencia en el grupo Ch III (p = 0,0001). El 69,42 ± 4,65% de los pacientes sufrió uno o más eventos cardíacos mayores (p = 0,06) con un riesgo relativo de 2,42 veces para estos sucesos [RR 2,4 IC 95 % (0,9 6,54)]. La asociación independiente entre fibrilación auricular y eventos cardíacos mayores no demostró diferencias estadísticamente significativas entre los grupos. La fibrilación auricular no se encontró asociada a la presencia de eventos cardíacos mayores, pero su incidencia en los pacientes con cardiopatía chagásica crónica es importante en los estadios avanzados de la enfermedad, principalmente en aquellos pacientes que presentan frecuencia ventricular izquierda deprimida.
Atrial fibrillation that accompanies chronic chagasiccardiomyopathy carries a poor prognosis, given its association with severe left ventricular systolic dysfunction and the formation of auricular thrombi with a tendency to systemic embolization. Atrial fibrillation was examined inpatients with Chagas disease in the northern Anzoátegui State.The relationship was examined between atrial fibrillation and major cardiac events such as cerebral vascular disease, death and non-elective hospitalization for cardiac causes. 98 patients chagásicos 56 male and 42 female with average age of 63.56 were classified into a sero-positive Ch I (normal electrocardiogram) group, a Ch II (abnormal electrocardiogram) group and a Ch III (abnormal ECG and heart failure) group and were followed for three consecutive years to determine the prevalence of atrial fibrillation and its association with the major cardiac events. The prevalence of atrial fibrillation in all the patients with Chagas disease was 22.84 ± 2.76%, found more frequently in the Ch III group (p = 0.0001). There were 69.42 ± 4.65% patients who suffered one or more major cardiac events (p = 0.06)with a relative risk of 2.42 for such events [RR 2.4 IC 95% (0.9 6.54)]. The independent association between atrial fibrillation and major cardiac events showed no statistically significant differences between groups. The atrial fibrillation not found associated with the presence of major cardiac events, but its impact the incidence of atrial fibrillation in patients with chronic chagasic cardiomyopathy is important in the later stages of the disease, mainly in those patients who have depressed left ventricular function.
الموضوعات
Humans , Male , Female , Middle Aged , Chagas Cardiomyopathy/pathology , Chagas Disease/diagnosis , Atrial Fibrillation/pathologyالموضوعات
Humans , Male , Middle Aged , Anticoagulants/adverse effects , Heart Failure/pathology , Hypertension/pathology , Obesity, Morbid/pathology , Stroke/chemically induced , Anticoagulants/therapeutic use , Atrial Fibrillation/pathology , Atrial Fibrillation/therapy , Fatal Outcome , Obesity, Morbid/complications , Sepsis/etiologyالملخص
Atrial fibrillation is the most common arrhythmia in clinical practice, may coexist with conditions common to both cardiovascular and noncardiovascular diseases and is associated with considerable morbidity and mortality. Atrial fibrillation is often asymptomatic and diagnosed only when it has caused a potentially serious complication, such as an ischemic stroke. When atrial fibrillation has been identified, 2 objectives have to be addressed - the antiarrhythmic therapy based on rate control or rhythm control, and prevention of thromboembolism. A rhythm or rate control strategy can be chosen indifferently because they have comparable efficacy for the outcome measure of mortality, but the antithrombotic therapy is ever mandatory. The risk of stroke increases cumulatively with increasing age, previous transient ischemic attack or stroke, hypertension, diabetes mellitus, impaired left ventricular function and heart failure. Warfarin reduces the risk of stroke by about two thirds; and aspirin, by about one fifth, but its use must be weighted with the risk of bleeding. The risk of anticoagulant-associated hemorrhage increases with age, the presence of serious concomitant diseases, with poorly controlled hypertension and poorly controlled anticoagulation.
الموضوعات
Anti-Arrhythmia Agents/adverse effects , Anti-Arrhythmia Agents/therapeutic use , Anticoagulants/therapeutic use , Aspirin/therapeutic use , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Atrial Fibrillation/pathology , Fibrinolytic Agents/adverse effects , Fibrinolytic Agents/therapeutic use , Humans , Platelet Aggregation Inhibitors/therapeutic use , Risk Factors , Stroke/etiology , Stroke/prevention & control , Thromboembolism/prevention & control , Warfarin/therapeutic useالملخص
La ablación por radiofrecuencia (ARF) es aceptada en la actualidad como tratamiento de la fibrilación auricular (FA) paroxística y persistente. El objetivo del presente trabajo es comparar los resultados de la ablación por radiofrecuencia con diferentes técnicas...
Radiofrequency catheter ablation (RFA) is one of the currently accepted treatments for paroxysmal and persistent atrial fibrillation (AF). Different approaches are currently used. To analyze the results of RFA in patients (pts.) with paroxysmal and persistent AF performing different techniques...
الموضوعات
Humans , Catheter Ablation , Atrial Fibrillation/pathology , Pulmonary Veins , Tachycardia, Paroxysmal/pathologyالموضوعات
Aged , Female , Humans , Atrial Fibrillation/etiology , Gastrointestinal Hemorrhage/etiology , Mitral Valve Stenosis/etiology , Rheumatic Heart Disease/complications , Shock/etiology , Atrial Fibrillation/pathology , Chronic Disease , Fatal Outcome , Gastrointestinal Hemorrhage/pathology , Mitral Valve Stenosis/pathology , Rheumatic Heart Disease/pathology , Shock/pathologyالموضوعات
Humans , Female , Aged , Atrial Fibrillation/complications , Cardiomyopathy, Hypertrophic/complications , Mesenteric Arteries/pathology , Pulmonary Embolism/complications , Atrial Fibrillation/pathology , Cardiomyopathy, Hypertrophic/pathology , Electrocardiography , Fatal Outcome , Pulmonary Embolism/pathology , Shock, Cardiogenicالملخص
Since the first report of radiofrequency catheter ablation curing atrial fibrillation (AF) nearly a decade ago, numerous techniques have evolved, from linear ablation to modify the reentrant sustrate for AF, to electrical isolation of pulmonary vein to eliminate triggers of AF, to hibrid approaches of circunferential ablation around and between the pulmonary veins and mitral valve annulus to modify both the triggers and sustrate for AF. We describe the electroanatomic mapping system (CARTO, Biosense Webster) and its use in patients undergoing catheter ablation for AF.
الموضوعات
Female , Humans , Male , Middle Aged , Atrial Fibrillation , Catheter Ablation/methods , Atrial Fibrillation/pathology , Atrial Fibrillation , Electrophysiologyالملخص
OBJETIVO: Avaliar se a estimulação atrial com corrente elétrica contínua pulsátil induz fibrilação atrial e os seus efeitos sobre as propriedades eletrofisiológicas atriais e as alterações histológicas atriais. MÉTODOS: Foram submetidos à toracotomia lateral direita 22 cães e implantados eletrodos de marcapasso no sulcus terminalis (ST), apêndice atrial direito (ADb) e na região póstero-inferior do átrio esquerdo (AE); um par de eletrodos foi suturado na auriculeta direita para estimulação com bateria alcalina de 9 Volts conectada a uma sistema (LM 555) que transforma a energia contínua linear da bateria em corrente contínua pulsátil, durante 60 min. A biópsia epicárdica atrial foi realizada antes e após a estimulação atrial. RESULTADOS: Não foram observadas diferenças nas durações dos períodos refratários efetivos atriais. Os tempos de condução intra-atrial, interatrial, bem como dos extra-estímulos atriais também prolongaram-se. A duração dos eletrogramas atriais prolongou-se durante ritmo sinusal e estimulação atrial programada; em 68 por cento dos cães a fibrilação atrial foi induzida e sustentou-se. Foram observados edema intersticial e bandas de contração celular no subepicárdio à microscopia óptica, e intensa desorganização miofibrilar e aumento do tamanho das mitocôndrias à microscopia eletrônica. CONCLUSÃO: Esta técnica de estimulação atrial induz fibrilação atrial e provoca modificações atriais que aumentam sua vulnerabilidade para o surgimento de fibrilação atrial.
الموضوعات
Animals , Dogs , Female , Male , Atrial Fibrillation/physiopathology , Electric Stimulation , Atrial Fibrillation/etiology , Atrial Fibrillation/pathology , Disease Models, Animal , Electric Stimulation/adverse effects , Electric Stimulation/instrumentation , Electric Stimulation/methods , Electrophysiology , Heart Atria/ultrastructure , Microscopy, Electron , Time Factorsالملخص
El síndrome de Brugada está constituido por un patrón electrocardiográfico característico y tendencia a presentar síncopes o paro cardiaco por arritmias ventriculares malignas. La asociación de fibrilación auricular es de un 10por cento. En las últimos 6 anos atendimos 15 pacientes (13 masculinos), portadores de esa entidad; en dos se constataron episodios de fibrilación auricular y otro tenía documentado una taquicardia intranodal. El primero había presentado un síncope, la estimulación eléctrica programada desde ventrículo derecho desencadenó fibrilación ventricular autolimitada, se le implantá un desfibrilador automático; el segundo aquejaba palpitaciones irregulares, de corta duración, se le indujo fibrilación auricular por manipulación de catéteres, la estimulación eléctrica programada no provocá arritmias. Al paciente con taquicardia intranodal se le realizá ablación exitosa de la via lenta, previa estimulación eléctrica programada desde ventrículo derecho negativa. Ninguno de ellos tenía antecedentes familiares de muerte súbita. En el seguimiento entre 3 y 15 meses, el primer paciente ai que se implantá el desfibrilador automático presentó dos descargas eléctricas dei mismo por episodios nocturnos de fibrilación ventricular, el segundo paciente presentó otro episodio similar de palpitaciones autolimitadas y el tercero se mantiene asintomático, sin fármacos. La incidencia de arritmias supraventriculares en esta entidad es elevada. Las manifestaciones clínicas, la documentación de la taquicardia y la estimulación eléctrica programada nos permitirán diagnosticarias y tratarias adecuadamente
الموضوعات
Humans , Male , Female , Arrhythmias, Cardiac , Atrial Fibrillation/diagnosis , Atrial Fibrillation/pathology , Tachycardia , Echocardiography , Syncope/diagnosis , Syncope/pathologyالملخص
Paciente do sexo feminino, com 58 anos, portadora de cardiomiopatia dilatada, acompanhada desde 1984 por apresentar insuficiência cardíaca e hipertensão arterial. Na evolução, apresentou bloqueio de ramo esquerdo e fibrilação atrial. No final de 1999, mesmo com a medicação adequada e otimizada para insuficiência cardíaca, apresentava-se em grau funcional IV e as internações hospitalares haviam se tornando cada vez mais freqüentes. Em janeiro de 2000, optou-se pela ablação do nó atrioventricular e pelo implante de um marcapasso endocárdico bifocal multissítio em ventrículo direito. Desde então vem evoluindo bem, com menor número de medicamentos e raras internações