Arterial stiffness: a possible predictor of atrial fibrillation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting 0.5%-1% of people worldwide. Hemodynamic changes due to stiffening of the arteries may cause cardiac structural and electrical remodeling that induces AF.Pulse wave velocity (PWV) is a direct non-invasive method to measure arterial stiffness (AS). Central pulse pressure (PPc) describes oscillations around the mean arterial pressure and is increased in more rigid arteries. These two central variables can be considered markers of AF. Sympathetic activity has been reported to be directly relatedto PWV even in patients without comorbidities. Therefore, in patients with more rigid arteries, sudden changes in pressure could affect the activation of arterial baroreceptors, leading to an acute imbalance between the sympathetic and parasympathetic responses in the heart. The coexistence of AF and AS is common. This critical review aims to bring information about the role of AS in the pathophysiology of AF and discuss results of clinical studies on this topic. Althuogh discussed in the literature, further studies are needed to confirm the predictive role of these variables in AF, and their use in clinical practice.

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

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

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

Recommendations for the Post-Mortem Management of Cardiac Implantable Electronic Devices. / Recomendações para o Manejo de Dispositivos Cardíacos Eletrônicos Implantáveis Post Mortem.

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

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

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

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

Predictors of Total Mortality and Echocardiographic Response for Cardiac Resynchronization Therapy: A Cohort Study / Preditores de Mortalidade Total e de Resposta Ecocardiográfica à Terapia de Ressincronização Cardíaca: Um Estudo de Coorte

Abstract Background: Clinical studies demonstrate that up to 40% of patients do not respond to cardiac resynchronization therapy (CRT), thus, appropriate patient selection is critical to the success of CRT in heart failure. Objective: Evaluation of mortality predictors and response to CRT in the Brazilian scenario. Methods: Retrospective cohort study including patients submitted to CRT in a tertiary hospital in southern Brazil from 2008 to 2014. Survival was assessed through a database of the State Department of Health (RS). Predictors of echocardiographic response were evaluated using Poisson regression. Survival analysis was performed by Cox regression and Kaplan Meyer curves. A two-tailed p value less than 0.05 was considered statistically significant. Results: A total of 170 patients with an average follow-up of 1011 ± 632 days were included. The total mortality was 30%. The independent predictors of mortality were age (hazard ratio [HR] of 1.05, p = 0.027), previous acute myocardial infarction (AMI) (HR of 2.17, p = 0.049) and chronic obstructive pulmonary disease (COPD) (HR of 3.13, p = 0.015). The percentage of biventricular stimulation at 6 months was identified as protective factor of mortality ([HR] 0.97, p = 0.048). The independent predictors associated with the echocardiographic response were absence of mitral insufficiency, presence of left bundle branch block and percentage of biventricular stimulation. Conclusion: Mortality in patients submitted to CRT in a tertiary hospital was independently associated with age, presence of COPD and previous AMI. The percentage of biventricular pacing evaluated 6 months after resynchronizer implantation was independently associated with improved survival and echocardiographic response.

Resumo Fundamento: Estudos Clínicos demonstram que até 40% dos pacientes não respondem à terapia de ressincronização cardíaca (TRC), assim a seleção apropriada dos pacientes é fundamental para o sucesso da TRC na insuficiência cardíaca. Objetivo: Avaliação de preditores de mortalidade e resposta à TRC no cenário brasileiro. Métodos: Estudo de coorte retrospectivo incluindo os pacientes submetidos à TRC em hospital terciário no Sul do Brasil entre 2008-2014. A sobrevida foi avaliada através de banco de dados da Secretaria Estadual de Saúde (RS). Os preditores de resposta ecocardiográfica foram avaliados utilizando método de regressão de Poisson. A análise de sobrevida foi feita por regressão de Cox e curvas de Kaplan Meyer. Um valor de p bicaudal inferior a 0,05 foi considerado estatisticamente significativo. Resultados: Foram incluídos 170 pacientes com seguimento médio de 1011 ± 632 dias. A mortalidade total foi de 30%. Os preditores independentes de mortalidade identificados foram idade (hazzard ratio [HR] de 1,05; p = 0,027), infarto agudo do miocárdio (IAM) prévio (HR de 2,17; p = 0,049) e doença pulmonar obstrutiva crônica (DPOC) (HR de 3,13; p = 0,015). O percentual de estimulação biventricular em 6 meses foi identificado com fator protetor de mortalidade ([HR] 0,97; p = 0,048). Os preditores independentes associados à reposta ecocardiográfica foram ausência de insuficiência mitral, presença de bloqueio de ramo esquerdo e percentual de estimulação biventricular. Conclusão: A mortalidade nos pacientes submetidos à TRC em hospital terciário foi independentemente associada à idade, presença de DPOC e IAM prévio. O percentual de estimulação biventricular avaliado 6 meses após o implante do ressincronizador foi independentemente associado a melhora da sobrevida e resposta ecocardiográfica.

Predictors of Total Mortality and Echocardiographic Response for Cardiac Resynchronization Therapy: A Cohort Study.

BACKGROUND: Clinical studies demonstrate that up to 40% of patients do not respond to cardiac resynchronization therapy (CRT), thus, appropriate patient selection is critical to the success of CRT in heart failure. OBJECTIVE: Evaluation of mortality predictors and response to CRT in the Brazilian scenario. METHODS: Retrospective cohort study including patients submitted to CRT in a tertiary hospital in southern Brazil from 2008 to 2014. Survival was assessed through a database of the State Department of Health (RS). Predictors of echocardiographic response were evaluated using Poisson regression. Survival analysis was performed by Cox regression and Kaplan Meyer curves. A two-tailed p value less than 0.05 was considered statistically significant. RESULTS: A total of 170 patients with an average follow-up of 1011 ± 632 days were included. The total mortality was 30%. The independent predictors of mortality were age (hazard ratio [HR] of 1.05, p = 0.027), previous acute myocardial infarction (AMI) (HR of 2.17, p = 0.049) and chronic obstructive pulmonary disease (COPD) (HR of 3.13, p = 0.015). The percentage of biventricular stimulation at 6 months was identified as protective factor of mortality ([HR] 0.97, p = 0.048). The independent predictors associated with the echocardiographic response were absence of mitral insufficiency, presence of left bundle branch block and percentage of biventricular stimulation. CONCLUSION: Mortality in patients submitted to CRT in a tertiary hospital was independently associated with age, presence of COPD and previous AMI. The percentage of biventricular pacing evaluated 6 months after resynchronizer implantation was independently associated with improved survival and echocardiographic response.

Atrial-oesophageal fistula following percutaneous radiofrequency catheter ablation of atrial fibrillation: the risk still persists.

Aims: Atrial-oesophageal fistula is a serious complication related to ablation of atrial fibrillation. As its occurrence is rare, there is a great lack of information about their mechanisms, incidence, presentations, and treatment. The objective of this manuscript is to present a series of cases of atrial-oesophageal fistula in Brazil, focusing on incidence, clinical presentation, and follow-up. Methods and results: This is a retrospective multicentre registry of atrial-oesophageal fistula cases that occurred in eight Brazilian centres from 2003 to 2015. Ten cases (0.113%) of atrial-oesophageal fistula were reported in 8863 ablation procedures in the period. Most of the subjects were male (70%) with age 59.6 ± 9.3 years. Eight centres were reference units in atrial fibrillation ablation with an experience over than 200 procedures at the time of fistula occurrence. Oesophageal temperature monitoring was performed in eight cases using coated sensors in six. The first atrial-oesophageal fistula clinical manifestation was typically fever (in six patients), with a median onset time of 16.5 (12­43) days after ablation. There was a delay of 7.8 ± 3.3 days between the first manifestation and the diagnosis in five patients. The treatment was surgical in six cases, clinical in three and stenting in one. Seven patients died (70%) and two developed permanent neurological sequelae. Conclusion: Atrial-oesophageal fistula remains a serious complication following AF ablation despite the incorporation of protective measures and increased technical experience of the groups. The high morbidity and mortality despite the treatment indicates the need to develop adequate preventive strategies.

Prevalence of oral anticoagulation in atrial fibrillation.

OBJECTIVES: Atrial fibrillation is the most common sustained arrhythmia and is associated with poor outcomes, including stroke. The ability of anticoagulation therapy to reduce the risk of stroke has been well established; however, the prevalence of anticoagulation therapy use in the Public Health System is unknown. The aim of this study is to evaluate both the prevalence of anticoagulation therapy among patients with atrial fibrillation and the indications for the treatment. METHODS: In this cross-sectional study, we included consecutive patients who had atrial fibrillation documented by an electrocardiogram performed between September 2011 and March 2012 at a university hospital of the Public Health System. The variables analyzed included the risk of a thromboembolic event and/or bleeding, the use of antiplatelet or anticoagulation therapy, the location where the electrocardiogram report was initially reviewed and the specialty of the physician who initially reviewed it. RESULTS: We included 162 patients (mean age 68.9 years, 56% men). Hypertension (90.1%), heart failure (53.4%) and stroke (38.9%) were the most prevalent diseases found. Only 50.6% of the patients knew that they had atrial fibrillation. Regarding the use of therapy, only 37.6% of patients classified as high risk according to the CHADS2 scores and 35.5% according to the CHA2DS2VASc used oral anticoagulation. A presumptive diagnosis of heart failure and the fact that the electrocardiogram was evaluated by a cardiologist were the only independent predictors of the use of anticoagulants. CONCLUSIONS: Our study found a low prevalence of oral anticoagulation therapy among patients with atrial fibrillation and an indication for stroke prophylaxis for the use of this therapy, including among those with high CHADS2 and CHA2DS2VASc scores.

Prevalence of oral anticoagulation in atrial fibrillation

OBJECTIVES: Atrial fibrillation is the most common sustained arrhythmia and is associated with poor outcomes, including stroke. The ability of anticoagulation therapy to reduce the risk of stroke has been well established; however, the prevalence of anticoagulation therapy use in the Public Health System is unknown. The aim of this study is to evaluate both the prevalence of anticoagulation therapy among patients with atrial fibrillation and the indications for the treatment. METHODS: In this cross-sectional study, we included consecutive patients who had atrial fibrillation documented by an electrocardiogram performed between September 2011 and March 2012 at a university hospital of the Public Health System. The variables analyzed included the risk of a thromboembolic event and/or bleeding, the use of antiplatelet or anticoagulation therapy, the location where the electrocardiogram report was initially reviewed and the specialty of the physician who initially reviewed it. RESULTS: We included 162 patients (mean age 68.9 years, 56% men). Hypertension (90.1%), heart failure (53.4%) and stroke (38.9%) were the most prevalent diseases found. Only 50.6% of the patients knew that they had atrial fibrillation. Regarding the use of therapy, only 37.6% of patients classified as high risk according to the CHADS2 scores and 35.5% according to the CHA2DS2VASc used oral anticoagulation. A presumptive diagnosis of heart failure and the fact that the electrocardiogram was evaluated by a cardiologist were the only independent predictors of the use of anticoagulants. CONCLUSIONS: Our study found a low prevalence of oral anticoagulation therapy among patients with atrial fibrillation and an indication for stroke prophylaxis for the use of this therapy, including among those with high CHADS2 and CHA2DS2VASc scores. .

Ablacao de Fibrilacao Atrial por Mapeamento Eletroanatomico: Eficacia e Fatores de Recorrencia / Atrial Fibrillation Ablation by Use of Electroanatomical Mapping: Efficacy and Recurrence Factors

Fundamento: A ablação por cateter de radiofrequência guiada por mapeamento eletroanatômico é, atualmente, uma importante opção terapêutica para o tratamento da fibrilação atrial. A complexidade do procedimento, as diferentes técnicas e a diversidade de pacientes dificultam a reprodução dos resultados bem como a indicação do procedimento. Objetivo: Avaliar a eficácia e os fatores relacionados à recorrência de fibrilação atrial. Métodos: Estudo de coorte prospectivo com pacientes consecutivos submetidos ao tratamento de fibrilação atrial por ablação e mapeamento eletroanatômico. Foram incluídos os seguintes pacientes: idade acima de 18 anos; portadores de fibrilação atrial paroxística, persistente ou persistente de longa duração; com registro de fibrilação atrial em eletrocardiograma, Holter ou ergometria (duração > 15 minutos); com sintomas associados aos episódios de fibrilação atrial; e apresentando refratariedade a, pelo menos, duas drogas antiarrítmicas (entre elas amiodarona) ou impossibilidade do uso de drogas antiarrítmicas. Resultados: Foram incluídos 95 pacientes (idade 55 ± 12 anos, 84% homens, CHADS2 médio = 0,8) que realizaram 102 procedimentos com seguimento mediano de 13,4 meses. A taxa livre de recorrência após o procedimento foi de 75,5% após 12 meses. Os pacientes portadores de fibrilação atrial paroxística e fibrilação atrial persistente apresentaram recorrência de 26,9% versus 45,8% dos pacientes portadores de fibrilação atrial persistente de longa duração (p = 0,04). Das variáveis analisadas, o tamanho do átrio esquerdo demonstrou ser preditor independente de recorrência de fibrilação atrial após ...

Background: Radiofrequency catheter ablation guided by electroanatomical mapping is currently an important therapeutic option for the treatment of atrial fibrillation. The complexity of the procedure, the several techniques used and the diversity of the patients hinder the reproduction of the results and the indication for the procedure. Objective: To evaluate the efficacy and factors associated with recurrence of atrial fibrillation. Methods: Prospective cohort study with consecutive patients submitted to atrial fibrillation ablation treatment guided by electroanatomical mapping. The inclusion criteria were as follows: minimum age of 18 years; presence of paroxysmal, persistent or long-standing persistent AF; AF recording on an electrocardiogram, exercise testing or Holter monitoring (duration longer than 15 minutes); presence of symptoms associated with AF episodes; AF refractoriness to, at least, two antiarrhythmic drugs, one of which being amiodarone, or impossibility to use antiarrhythmic drugs. Results: The study included 95 patients (age 55 ± 12 years, 84% men, mean CHADS2 = 0.8) who underwent 102 procedures with a median follow-up of 13.4 months. The recurrence-free rate after the procedure was 75.5% after 12 months. Atrial fibrillation recurred as follows: 26.9% of patients with paroxysmal and persistent atrial fibrillation; 45.8% of patients with long-standing persistent atrial fibrillation (p = 0.04). Of the analyzed variables, the increased size of the left atrium has proven to be an independent predictor of atrial fibrillation recurrence after the procedure (HR = 2.58; 95% CI: 1.26-4.89). Complications occurred in 4.9% of the procedures. Conclusion: Atrial fibrillation ablation guided by electroanatomical mapping has shown good efficacy. The increase in left atrium size was associated with atrial fibrillation recurrence. .

Atrial fibrillation ablation by use of electroanatomical mapping: efficacy and recurrence factors.

BACKGROUND: Radiofrequency catheter ablation guided by electroanatomical mapping is currently an important therapeutic option for the treatment of atrial fibrillation. The complexity of the procedure, the several techniques used and the diversity of the patients hinder the reproduction of the results and the indication for the procedure. OBJECTIVE: To evaluate the efficacy and factors associated with recurrence of atrial fibrillation. METHODS: Prospective cohort study with consecutive patients submitted to atrial fibrillation ablation treatment guided by electroanatomical mapping. The inclusion criteria were as follows: minimum age of 18 years; presence of paroxysmal, persistent or long-standing persistent AF; AF recording on an electrocardiogram, exercise testing or Holter monitoring (duration longer than 15 minutes); presence of symptoms associated with AF episodes; AF refractoriness to, at least, two antiarrhythmic drugs, one of which being amiodarone, or impossibility to use antiarrhythmic drugs. RESULTS: The study included 95 patients (age 55 ± 12 years, 84% men, mean CHADS2 = 0.8) who underwent 102 procedures with a median follow-up of 13.4 months. The recurrence-free rate after the procedure was 75.5% after 12 months. Atrial fibrillation recurred as follows: 26.9% of patients with paroxysmal and persistent atrial fibrillation; 45.8% of patients with long-standing persistent atrial fibrillation (p = 0.04). Of the analyzed variables, the increased size of the left atrium has proven to be an independent predictor of atrial fibrillation recurrence after the procedure (HR = 2.58; 95% CI: 1.26-4.89). Complications occurred in 4.9% of the procedures. CONCLUSION: Atrial fibrillation ablation guided by electroanatomical mapping has shown good efficacy. The increase in left atrium size was associated with atrial fibrillation recurrence.

Avaliação da função renal após a terapia de ressincronização cardíaca / Assessment of renal function after cardiac resynchronization therapy

A síncope é um problema médico comum e, se relacionada a distúrbio da condução atrioventricular (AV), pode indicar o implante de marcapasso definitivo. Por isso, a distinção entre o bloqueio AV devido a doença degenerativa e aquele induzido por aumento do tônus vagal tem importante implicação prognóstica e terapêutica. O mecanismo responsável pela síncope vasovagal é a perda abrupta e transitória da consciência decorrente de hipoperfusão cerebral global e transitória, com início rápido, curta duração e recuperação completa e espontânea. É uma causa comum de síncope e tem bom prognóstico. Em sua forma cardioinibitória, costuma ter como mecanismo a bradicardia sinusal ou a assistolia associada a queda da pressão sanguínea, porém podem ocorrer outras apresentações menos comuns, como o bloqueio AV (BAVT, BAV 2:1 BAV avançado). Descreve-se o caso de uma paciente do sexo feminino, com 54 anos, hipertensa, chagásica (megaesôfago) e vários episódios de síncope no último ano. Foi investigada com eletrocardiograma (BAV 1º grau), ecocardiograma (normal), Holter (BAV 2 grau Mobitz I durante o sono), teste ergométrico (resposta cronotrópica e condução AV normais durante o esforço) e tilt test sensibilizado positivo (BAVT) com manutenção de distúrbios da condução atrioventricular (BAVT, BAV avançado) associados a pré-síncope após retorno a zero grau, quadro que durou 25 minutos. Como parte da investigação, foi submetida a estudo eletrofisiológico com intervalo HV normal. Foi indicado marcapasso definitivo, porém a paciente recusou-se. Retornou após um ano com manutenção do quadro de síncope. Foi então submetida a implante de marcapasso definitivo de dupla-câmara e encontra-se há 15 meses sem sintomas.

Abstract: Syncope is a common medical problem and if related to disorder of atrioventricular (AV) conduction may be indicative of permanent pacemaker implantation. Therefore, the distinction between AV block due to degenerative disease and that induced by increased vagal tone has important prognostic and therapeutic implications. The mechanism responsible for vasovagal syncope is a sudden and transient loss of consciousness due to global cerebral hypoperfusion with rapid onset, short duration, and spontaneous complete recovery. It is a common cause of syncope and has a good prognosis. When cardioinhibitory, usually has as a mechanism of syncope sinus bradycardia or asystole associated to drop in blood pressure, but other less common presentations may occur as AV block (AVB, advanced AVB, AVB 2:1). We describe the case of a female patient, 54 years old, with hypertension, Chagas disease (megaesophagus) and several episodes of syncope in the last year. She was investigated by electrocardiogram (1st degree AVB), echocardiogram (normal), holter (Mobitz I 2nd degree AVB during sleep), exercise testing (normal chronotropic response and AV conduction during exercise) and tilt test (complete AVB) with maintenance of atrioventricular block (complete AVB and advanced AVB) associated with pre-syncope after returning to zero degree. This situation last for 25 minutes. As part of the investigation she underwent electrophysiologic study with normal HV interval. Permanent pacemaker was indicated but the patient refused. After 1 year she returned with maintenance of syncope and then underwent implantation of a permanent dual chamber pacemaker. She is without symptoms in the last 15 months.

Avaliação da estabilidade de anticoagulação entre a Varfarina e a Femprocumona / Oral anticoagulation stability assessment with Warfarin and Phenprocoumon

Fundamentos: A varfarina e a femprocumona são os anticoagulantes orais mais utilizados; no entanto, até então, não existem estudos randomizados comparando a estabilidade da anticoagulação entre estes dois fármacos. Objetivos: Comparar a varfarina e femprocumona quanto à estabilidade na manutenção de anticoagulação em nível terapêutico (razão normatizada internacional [RNI] entre 2,0 e 3,0) e avaliar a incidência de complicações hemorrágicas e tromboembólicas decorrentes de anticoagulação inadequada.Métodos: Ensaio clínico, randomizado, duplo-cego, incluindo pacientes em tratamento vigente com anticoagulante oral, porém com RNI abaixo do alvo terapêutico nas últimas três semanas, randomizados para uso de varfarina ou femprocumona. O ajuste da dose da medicação foi realizado conforme algoritmo pré-estabelecido. Resultados: Foram randomizados 62 pacientes, sendo 31 em cada grupo, durante as cinco primeiras semanas de estudo. Verificou-se que a femprocumona se mostrou mais instável comparada à varfarina. A partir da sexta aferição de RNI, o grupo femprocumona apresentou melhora na estabilidade do valor do RNI, porém não houve significância estatística. Também não houve diferença significativa em relação aos efeitos colaterais dos fármacos. Conclusão: A varfarina demonstrou maior eficácia na estabilidade do RNI em relação à femprocumona.

Background: Although warfarin and phenprocoumon are the most widely used oral anticoagulants, there a r e n o r a n d o m i z e d s t u d i e s c o m p a r i n g t h e anticoagulation stability of these two drugs.Objectives: To compare warfarin and phenprocoumon in terms of therapeutic anticoagulation maintenance stability (international normalized ratio [INR] between 2.0 and 3.0) and evaluate the incidence of thromboembolic and hemorrhagic complications arising from inadequate anticoagulation.Methods: Randomized double-blind clinical trial with patients undergoing current oral anticoagulant treatment but with INR below the therapeutic target during the past 3 weeks, randomized for warfarin or phenprocoumon. Medication dosages were adjusted in compliance with a predetermined algorithm.Results: With 62 patients randomized into two groups of 31 each during the first five weeks of the study, phenprocoumon was found to be more unstable than warfarin. From the sixth INR measurement onwards, the stability of the INR value improved in the phenprocoumon group, but with no statistical significance. There were no significant differences in the side effects of the drugs.Conclusion: Warfarin demonstrated greater effectiveness for INR stability than phenprocoumon.

Ablação por cateter de taquicardias ventriculares em pacientes sem cardiopatia estrutural / Catheter ablation of ventricular tachycardia in patients without structural heart disease

As taquicardias ventriculares idiopáticas ocorrem em pacientes com coração estruturalmente normal e podem se originar nos dois ventriculos ou em estruturas vizinhas. Essas arritmias são classificadas usualmente conforme o seu local de origem, mecanismos eletrofisiológico e resposta à drogas, apresentando bom prognóstico na maioria dos casos. A ablação por cateter é uma opção terapêutica importante, geralmente empregada após o manejo clínico inicial, sendo o tratamento guiado pricipalmente pelos sintomas. As técnicas de ablação tradicionais permitem tratar com sucesso a maioria das TV idiopáticas, com o auxílio de sistemas se mapeamento eletroanatômico em alguns casos.