Displasia arritmogênica do ventrículo direito: relato de caso e revisão dos critérios diagnósticos e atuais das indicações de cardiodesfibrilador implantável / Arrhythmogenic right ventricular dysplasia: case report and review of diagnostic criteria and current indications for implantable cardioverter defibrillator(ICD)

A displasia arritmogênica do ventrículo direito é uma forma de cardiomiopatia geneticamentedeterminada, que afeta primariamente o ventrículo direito. Caracteriza-se pela substituição dos miócitos portecido fibrogorduroso. É considerada uma doença cardíaca potencialmente letal e tem sido associada a arritmias,insuficiência cardíaca e morte súbita. Relata-se o caso clínico de um paciente jovem, em que a síncope foi aprimeira manifestação da doença.

Arrhythmogenic right ventricular dysplasia is a genetically determined form of cardiomyopathy thatprimarily affects the right ventricle. It is characterized by a gradual replacement of the myocytes by adipose andfibrous tissue. It is considered a potentially lethal heart disease and has been associated with arrhythmias, heartfailure, and sudden death. In this paper, we report a clinical case of a young man that presented syncope as firstmanifestation of the disease.

Ablação com RF de arritmia na infância: registro observacional em 125 crianças / Radiofrequency ablation of childhood arrhythmia: observational registry in 125 children

FUNDAMENTO: Ablação por radiofrequência (ARF) em crianças consiste em uma prática cada vez mais frequente. OBJETIVO: Avaliar, em nossa instituição, os resultados da ARF em crianças com idade abaixo de 15 anos. MÉTODOS: Foram analisadas 125 crianças submetidas à ARF entre maio de 1991 a maio de 2010. RESULTADOS: Sessenta e sete (53,6%) crianças eram do sexo masculino, com idade entre 44 dias e 15 anos (média de 8,6 ± 3,3 anos) e peso mediano de 31 kg. Cardiopatia esteve presente em 21 (16,8%) pacientes. A ARF de vias acessórias (VA) foi o procedimento mais comum (62 crianças - 49,6%). A ARF de taquicardias por reentrada nodal (TRN) foi a segunda arritmia mais frequente, em 27 (21,6%), seguida de taquicardias atriais (TA), em 16 (12,8%) e de taquicardias ventriculares (TV) em 8 (6,4%) crianças. Os critérios de sucesso foram alcançados em 86,9%, 96,1%, 80% e 62,5% dos pacientes submetidos à ARF de VA, TRN, TA e TV, respectivamente. Os bloqueios atrioventriculares transitórios (BAVT) ocorreram durante a ARF em 4 (3,2%) e BRD em 7 (5,6%) crianças. Vinte e cinco crianças foram submetidos à nova ARF por insucesso inicial ou recorrência. Durante o seguimento médio de 5,5 ± 3,4 anos, 107 (88,4%) persistiram sem recorrência. Não houve diferença estatística em relação aos resultados e à idade em que o paciente se submeteu ao procedimento. Nenhuma criança apresentou BAVT persistente ou necessitou de marca-passo definitivo. CONCLUSÃO: A ablação por cateter é uma alternativa terapêutica segura e eficiente em crianças com taquicardias recorrentes refratárias ao tratamento clínico.

BACKGROUND: Radiofrequency ablation (RFA) in children is an increasingly common practice. OBJECTIVE: To evaluate, in our institution, the results of RFA in children younger than 15 years. METHODS: A total of 125 children submitted to RFA between May 1991 and May 2010 were analyzed. RESULTS: Sixty-seven (53.6%) children were males, aged between 44 days and 15 years (mean 8.6 ± 3.3 years) with median weight of 31 kg. Heart disease was present in 21 (16.8%) patients. The RFA of accessory pathways (AP) was the most common procedure (62 children - 49.6%). The RFA of nodal reentrant tachycardia (NRT) was the second most common arrhythmia in 27 (21.6%), followed by atrial tachycardia (AT) in 16 (12.8%) and ventricular tachycardias (VT) in 8 (6.4%) children. The success criteria were achieved in 86.9%, 96.1%, 80% and 62.5% of patients undergoing RFA of AP, NRT, AT and VT, respectively. Transient AVB occurred during RFA in 4 (3.2%) and LBBB in 7 (5.6%) children. Twenty-five children underwent a new RFA due to initial failure or recurrence. During the mean follow up of 5.5 ± 3.4 years, 107 (88.4%) remained without recurrence. There was no statistical difference regarding the results and the age at which the patient underwent the procedure. No child had persistent AVB or required a permanent pacemaker. CONCLUSION: Catheter ablation is a safe and effective alternative therapy in children with recurrent tachycardias refractory to medical treatment.

Radiofrequency ablation of childhood arrhythmia: observational registry in 125 children.

BACKGROUND: Radiofrequency ablation (RFA) in children is an increasingly common practice. OBJECTIVE: To evaluate, in our institution, the results of RFA in children younger than 15 years. METHODS: A total of 125 children submitted to RFA between May 1991 and May 2010 were analyzed. RESULTS: Sixty-seven (53.6%) children were males, aged between 44 days and 15 years (mean 8.6 ± 3.3 years) with median weight of 31 kg. Heart disease was present in 21 (16.8%) patients. The RFA of accessory pathways (AP) was the most common procedure (62 children - 49.6%). The RFA of nodal reentrant tachycardia (NRT) was the second most common arrhythmia in 27 (21.6%), followed by atrial tachycardia (AT) in 16 (12.8%) and ventricular tachycardias (VT) in 8 (6.4%) children. The success criteria were achieved in 86.9%, 96.1%, 80% and 62.5% of patients undergoing RFA of AP, NRT, AT and VT, respectively. Transient AVB occurred during RFA in 4 (3.2%) and LBBB in 7 (5.6%) children. Twenty-five children underwent a new RFA due to initial failure or recurrence. During the mean follow up of 5.5 ± 3.4 years, 107 (88.4%) remained without recurrence. There was no statistical difference regarding the results and the age at which the patient underwent the procedure. No child had persistent AVB or required a permanent pacemaker. CONCLUSION: Catheter ablation is a safe and effective alternative therapy in children with recurrent tachycardias refractory to medical treatment.

Functional behavior of patients with conventional pacemakers undergoing cardiac resynchronization.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an efficient treatment for patients with heart failure (HF), severe ventricular dysfunction and intraventricular block. Conventional pacemakers (CPM) implanted in the right ventricular apical area cause alterations in the normal sequence of cardiac activation similar to those induced by LBBB (left bundle-branch block). Therefore, patients with CPM and advanced HF could be candidates to undergo CRT, but as only small numbers of patients have been evaluated so far, definitive conclusions are lacking. OBJECTIVE: To assess the clinical and functional outcome of cardiac resynchronization therapy (CRT) in patients with conventional pacemakers. METHODS: Patients with CPM, who were in NYHA HF functional class III/IV class refractory to drug therapy, and left ventricular ejection fraction (LVEF) ) <35% underwent CRT. Patients clinical-functional behavior was assessed prospectively six months after the procedure. The improvement of one HF-functional class was set as an effective response to the procedure. The following was assessed: QRS duration (ECG), diastolic diameter (LVDd), left ventricular systolic diameter (LVSd) and LVEF seen on the echocardiogram. For the statistical analysis, Students paired t test and Spearmans correlation were used. RESULTS: Twenty-nine patients (mean age 61.5) were evaluated. Of these, six were females, and chagasic cardiomyopathy was predominant. During the clinical follow-up of 22.7+/-13 months, 86.2% of the patients benefited from CRT. Within this group, the mean LVEF increased by 18% (p=0.013), QRS duration dropped by 11.8% (p=0.002) and no significant reduction in left ventricular intracavitary diameters was observed. CONCLUSION: CRT is effective for patients with CPM and advanced HF as it yields a high rate of response (86.2%), significantly improves LVEF and reduces QRS duration.

Comportamento funcional dos portadores de marcapasso convencional submetidos a ressincronização cardíaca / Functional behavior of patients with conventional pacemakers undergoing cardiac resynchronization

FUNDAMENTO: A terapia de ressincronização cardíaca (TRC) é eficiente no tratamento de pacientes com insuficiência cardíaca (IC), disfunção ventricular grave e bloqueio intraventricular. O marcapasso convencional (MPC) em região apical de ventrículo direito provoca alterações da seqüência de ativação normal do coração semelhante às do BRE. Nesse sentido, pacientes com MPC e IC avançada poderiam ser candidatos a TRC, mas reduzidas casuísticas foram avaliadas e não há conclusões definitivas. OBJETIVO: Analisar o comportamento clínico-funcional da terapia de ressincronização cardíaca (TRC) nos portadores de marcapasso convencional. MÉTODOS: Pacientes com MPC, IC-CF(NYHA) III/IV refratária a terapêutica medicamentosa, fração de ejeção do ventrículo esquerdo (FEVE) <35 por cento, foram submetidos a TRC. O comportamento clínico-funcional foi avaliado prospectivamente após seis meses. A redução de uma CF-IC foi estabelecida como resposta efetiva ao procedimento. Foram analisados: duração do QRS (ECG), diâmetro diastólico (DDVE), diâmetro sistólico do ventrículo esquerdo (DSVE) e FEVE ao ECO. A análise estatística utilizou os testes t de Student pareado e a correlação de Spearman. RESULTADOS: Vinte e nove pacientes com idade média de 61,5 anos foram estudados. Seis eram do sexo feminino e houve predomínio da cardiomiopatia chagásica. Em seguimento clínico de 22,7±13 meses, 86,2 por cento dos pacientes melhoraram com a TRC. Nesse grupo, a FEVE média aumentou em 18 por cento (p=0,013); houve redução da duração do QRS em 11,8 por cento (p=0,002) e não houve redução significativa dos diâmetros intracavitários do ventrículo esquerdo. CONCLUSÃO: A TRC é efetiva para pacientes com MPC e IC avançada porque proporciona taxa elevada de responsivos (86,2 por cento), melhora significativa da FEVE e redução da duração do QRS.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an efficient treatment for patients with heart failure (HF), severe ventricular dysfunction and intraventricular block. Conventional pacemakers (CPM) implanted in the right ventricular apical area cause alterations in the normal sequence of cardiac activation similar to those induced by LBBB (left bundle-branch block). Therefore, patients with CPM and advanced HF could be candidates to undergo CRT, but as only small numbers of patients have been evaluated so far, definitive conclusions are lacking. OBJECTIVE: To assess the clinical and functional outcome of cardiac resynchronization therapy (CRT) in patients with conventional pacemakers. METHODS: Patients with CPM, who were in NYHA HF functional class III/IV class refractory to drug therapy, and left ventricular ejection fraction (LVEF) ) <35 percent underwent CRT. Patients’ clinical-functional behavior was assessed prospectively six months after the procedure. The improvement of one HF-functional class was set as an effective response to the procedure. The following was assessed: QRS duration (ECG), diastolic diameter (LVDd), left ventricular systolic diameter (LVSd) and LVEF seen on the echocardiogram. For the statistical analysis, Student’s paired t test and Spearman’s correlation were used. RESULTS: Twenty-nine patients (mean age 61.5) were evaluated. Of these, six were females, and chagasic cardiomyopathy was predominant. During the clinical follow-up of 22.7±13 months, 86.2 percent of the patients benefited from CRT. Within this group, the mean LVEF increased by 18 percent (p=0.013), QRS duration dropped by 11.8 percent (p=0.002) and no significant reduction in left ventricular intracavitary diameters was observed. CONCLUSION: CRT is effective for patients with CPM and advanced HF as it yields a high rate of response (86.2 percent), significantly improves LVEF and reduces QRS duration.

Anatomic relations of the Marshall vein: importance for catheterization of the coronary sinus in ablation procedures.

AIMS: Our objective was to study the anatomic relations of the human left atrial oblique vein (Marshall vein), particularly of its ostium opening into the coronary sinus, in order to guide ablation procedures related to that vein. METHODS AND RESULTS: The study was carried out in 23 heart-specimens (mean weight 446 +/- 204 g) of individuals whose mean ages were 43 +/- 21 years, 20 males. The coronary sinus was opened longitudinally, exposing the ostium of the tributary veins; the Vieussens valve was looked for, as well as its relationship to the left atrial oblique vein. The diameters of the left atrial oblique vein and the coronary sinus ostia were measured and the distance between them was determined. The left atrial oblique vein could be identified in 20 (87%) of the hearts, while the Vieussens valve was present in 17 (74%) of the specimens (in 16 of which the left atrial oblique vein was identified). In such condition, the vein was adjacent to the Vieussens valve and proximally positioned relative to the coronary sinus ostium in most of them (14/16 cases). The mean diameters of the left atrial oblique vein and of the coronary sinus ostia were, respectively, 1.23 +/- 0.38 and 8.22 +/- 1.88 mm. The mean distance between both ostia was 30.9 +/- 10.2 mm. CONCLUSION: When present, the left atrial oblique vein can be easily recognized, adjacent to the Vieussens valve. The mean distance between the coronary sinus opening and left atrial oblique vein ostium was around 30 mm, independently of the heart weight and the presence of cardiomegaly.

Ventricular remodeling in right ventricular apical pacing.

OBJECTIVE: To determine ventricular remodeling (VR) and the role of clinical and functional variables in patients with normal cardiac function who underwent right ventricular apical pacing (RVAP). METHODS: Among the 268 consecutive patients with standard pacemaker due to complete atrioventricular block (CAVB), those with left ventricular ejection fraction (LVEF) < 55% and left ventricular end-diastolic diameter (LVEDD) > 53 mm on Doppler echocardiography were excluded. Ventricular remodeling was defined as echocardiographic changes documented at least six months after implantation, namely, a >10% increase in LVEDD and a > 20% decrease in LVEF. The following variables were analyzed: underlying heart disease, NYHA functional class of heart failure (HF), time of ventricular stimulation, and QRS duration. Statistical analysis included likelihood ratio test, Fishers exact test, and Wilcoxon rank-sum test. A p value < 0.05 was considered statistically significant. RESULTS: The study included 75 patients, mean age 70.9 +/- 14, of whom 22.6% were male. Mean time between both evaluations was 80.2 months. Before implantation, mean LVEF was 72% and LVEDD was 46 mm; after implantation this values were 69.7% (p = 0.0025) and 48.5 mm (p = 0.0001), respectively. Mean QRS duration after implantation was 156 ms. Ventricular remodeling was observed only in four patients (5.3%), and no exploratory variable specified this behavior. CONCLUSION: In a long-term follow-up, patients without ventricular dysfunction who underwent RV apical pacing (RVAP) showed low VR rate, and no analyzed variable was associated with its occurrence.

Remodelamento ventricular na estimulação cardíaca apical do ventrículo direito / Ventricular remodeling in right ventricular apical pacing

OBJETIVO: Avaliar a taxa de remodelamento ventricular (RV) e a importância de variáveis clínico-funcionais em pacientes com função cardíaca normal submetidos à estimulação artificial apical do ventrículo direito (VD). MÉTODOS: Dentre 268 pacientes consecutivos com BAVT e marcapasso convencional, foram excluídos os portadores de fração de ejeção do ventrículo esquerdo (FEVE) < 55 por cento e diâmetro diastólico do ventrículo esquerdo (DDVE) > 53 mm ao eco-Doppler. O RV foi definido como o conjunto de modificações ecocardiográficas documentadas pelo menos 6 meses pós-implante: aumento >10 por cento no DDVE e redução > 20 por cento na FEVE. As variáveis analisadas foram: cardiopatia de base, classe funcional de insuficiência cardíaca (IC), tempo de estimulação ventricular e duração do QRS. A análise estatística incluiu os testes da razão de verossimilhança, exato de Fisher e a soma de postos de Wilcoxon. O valor de p foi significante quando < 0,05. RESULTADOS: o estudo incluiu 75 pacientes com idade média de 70,9 ± 14 anos, 22,6 por cento do sexo masculino. O tempo médio entre as avaliações foi de 80,2 meses. A FEVE média pré-implante foi 72 por cento e o DDVE 46 mm e pós-implante, 69,7 por cento (p = 0,0025) e 48,5mm (p < 0,0001), respectivamente. A duração média do QRS pós-implante foi 156 ms. O RV ocorreu em apenas quatro pacientes (5,3 por cento), e nenhuma das variáveis exploratórias discriminou esse comportamento. CONCLUSÃO: Pacientes sem disfunção ventricular submetidos à estimulação cardíaca apical do VD em longo seguimento apresentaram baixa taxa de RV, e não foram definidos fatores associados para sua ocorrência.

OBJECTIVE: To determine ventricular remodeling (VR) and the role of clinical and functional variables in patients with normal cardiac function who underwent right ventricular apical pacing (RVAP). METHODS: Among the 268 consecutive patients with standard pacemaker due to complete atrioventricular block (CAVB), those with left ventricular ejection fraction (LVEF) < 55 percent and left ventricular end-diastolic diameter (LVEDD) > 53 mm on Doppler echocardiography were excluded. Ventricular remodeling was defined as echocardiographic changes documented at least six months after implantation, namely, a >10 percent increase in LVEDD and a > 20 percent decrease in LVEF. The following variables were analyzed: underlying heart disease, NYHA functional class of heart failure (HF), time of ventricular stimulation, and QRS duration. Statistical analysis included likelihood ratio test, FisherÆs exact test, and Wilcoxon rank-sum test. A p value < 0.05 was considered statistically significant. RESULTS: The study included 75 patients, mean age 70.9 ± 14, of whom 22.6 percent were male. Mean time between both evaluations was 80.2 months. Before implantation, mean LVEF was 72 percent and LVEDD was 46 mm; after implantation this values were 69.7 percent (p = 0.0025) and 48.5 mm (p = 0.0001), respectively. Mean QRS duration after implantation was 156 ms. Ventricular remodeling was observed only in four patients (5.3 percent), and no exploratory variable specified this behavior. CONCLUSION: In a long-term follow-up, patients without ventricular dysfunction who underwent RV apical pacing (RVAP) showed low VR rate, and no analyzed variable was associated with its occurrence.

Síncope em pacientes com extra-sístoles de via de saída de ventrículo direito e sem cardiopatia estrutural aparente / Syncope in patients with right ventricle outflow tract premature beats and no apparent structural cardiopathy

OBJETIVO: Estudar a prevalência de síncope neurocardiogênica em pacientes com síncope inexplicada e extra-sístoles ventriculares (EV), com morfologia de via de saída de ventrículo direito (VSVD) sem cardiopatia estrutural aparente. MÉTODOS: Noventa pacientes (66 mulheres, idade média de 40,2 ± 16,95 anos) com EV monomórficas com origem na VSVD foram avaliados prospectivamente. Cinqüenta e quatro pacientes apresentavam síncopes ou pré-síncopes associadas ou não a palpitações; 27 apresentavam palpitações sem pré-síncope ou síncope, e 9 eram assintomáticos. Todos foram submetidos a ecocardiograma, ECG de alta resolução, ressonância magnética cardíaca e teste de esforço para afastar cardiopatia estrutural e taquicardia ventricular adrenérgico-dependente, e a monitorização com Holter e monitor de eventos sintomáticos para correlacionar os sintomas com a arritmia. A investigação de suscetibilidade a síncope neurocardiogênica foi avaliada pelo teste de inclinação (TI). Os grupos foram comparados quanto a sexo, idade, freqüência e complexidade das extra-sístoles, com e sem esforço físico, resultado do TI e evolução clínica. RESULTADOS: No grupo com síncope e pré-síncope, o TI foi positivo em 38 por cento dos casos e nos grupos com palpitações e assintomáticos, em 11 por cento (p = 0,0257). Após orientação e tratamento da síncope neurocardiogênica, 85 por cento dos pacientes com síncope e pré-sincope e TI positivo permaneceram assintomáticos durante seguimento médio de 40 meses. Dois pacientes com síncope e TI negativos apresentaram taquicardia ventricular sustentada espontânea durante a evolução clínica. CONCLUSÃO: A prevalência de síncope neurocardiogênica em pacientes com EV idiopáticas de VSVD é alta. Pacientes com síncope recorrente inexplicada e EV idiopáticas devem ser mantidos sob investigação.

OBJECTIVE: Study the prevalence of neurocardiogenic etiology in patients with unexplained syncope and ventricular premature beats, with right ventricle outflow tract morphology (RVOT) and no apparent structural cardiopathy. METHODS: Ninety patients (66 women, mean age 40.2±16.95 years of age) with monomorphic premature beats originated at RVOT were evaluated prospectively. Fifty-four patients reported syncopes or near-syncopes associated to palpitations or not; twenty-seven presented palpitations with no pre-syncope or syncope, and nine were asymptomatic. All patients were submitted to echocardiogram, high resolution ECG and cardiac MRI to rule out structural cardiopathy, to exertion test to rule out adrenergic dependent ventricular tachycardia, and ECG prolonged outpatient monitoring (Holter and symptomatic events monitor) to correlate symptoms and ventricular arrhythmias. Investigation on the susceptibility to neurocardiogenic syncope was evaluated by Tilt Table Test (TTT). Groups were compared regarding gender, age, premature beats frequency and complexity, at exertion or not, TTT results and clinical course. RESULTS: In the syncope and pre-syncope groups, TTT was positive for 38 percent of cases, and in groups with palpitations and assymptomatics, it was positive for 11 percent (p = 0.0257). After recommendations and treatment of neurocardiogenic syncope, 85 percent of syncope and pre-syncope patients and positive TTT was asymptomatic along the 40-month follow-up. Two patients with syncope and negative TTT presented spontaneous, sustained ventricular tachycardia during clinic course. CONCLUSION: The prevalence of neurocardiogenic syncope in patients with idiopathic RVOT premature beats is high. Patients with recurrent, unexplained syncope and idiopathic VE must be kept under investigation.

Syncope in patients with right ventricle outflow tract premature beats and no apparent structural cardiopathy.

OBJECTIVE: Study the prevalence of neurocardiogenic etiology in patients with unexplained syncope and ventricular premature beats, with right ventricle outflow tract morphology (RVOT) and no apparent structural cardiopathy. METHODS: Ninety patients (66 women, mean age 40.2 +/- 16.95 years of age) with monomorphic premature beats originated at RVOT were evaluated prospectively. Fifty-four patients reported syncopes or near-syncopes associated to palpitations or not; twenty-seven presented palpitations with no pre-syncope or syncope, and nine were asymptomatic. All patients were submitted to echocardiogram, high resolution ECG and cardiac MRI to rule out structural cardiopathy, to exertion test to rule out adrenergic dependent ventricular tachycardia, and ECG prolonged outpatient monitoring (Holter and symptomatic events monitor) to correlate symptoms and ventricular arrhythmias. Investigation on the susceptibility to neurocardiogenic syncope was evaluated by Tilt Table Test (TTT). Groups were compared regarding gender, age, premature beats frequency and complexity, at exertion or not, TTT results and clinical course. RESULTS: In the syncope and pre-syncope groups, TTT was positive for 38% of cases, and in groups with palpitations and assymptomatics, it was positive for 11% (p = 0.0257). After recommendations and treatment of neurocardiogenic syncope, 85% of syncope and pre-syncope patients and positive TTT was asymptomatic along the 40-month follow-up. Two patients with syncope and negative TTT presented spontaneous, sustained ventricular tachycardia during clinic course. CONCLUSION: The prevalence of neurocardiogenic syncope in patients with idiopathic RVOT premature beats is high. Patients with recurrent, unexplained syncope and idiopathic VE must be kept under investigation.

Surgical treatment of atrial fibrillation through isolation of the left atrial posterior wall in patients with chronic rheumatic mitral valve disease. A randomized study with control group.

OBJECTIVE: To determine the effectiveness of surgical isolation of the left atrial posterior wall encompassing the ostia of the pulmonary veins for the treatment of atrial fibrillation of rheumatic etiology. METHODS: Prospective and randomized study of patients with rheumatic mitral valve disease, persistent atrial fibrillation for 6 months or longer, age < or = 60 years, and left atrial diameter < or = 65 mm. The patients were randomly distributed into 2 groups as follows: surgical valvular treatment (control group) and surgical valvular treatment associated with isolation of the left atrial posterior wall according to the "cut-and-sew" technique (treated group). RESULTS: Twenty-nine individuals were operated upon, 27 of whom (13 in the control group and 14 in the treated group) were regularly followed up. The patients of both groups did not differ in regard to their basal characteristics. The mean follow-up time was 11.5 months in the control group and 10.3 months in the treated group. The cumulative frequencies of the patients without atrial fibrillation were significantly greater in the treated group both in the perioperative (P = 0.0035) and late (P = 0.0430) phases. CONCLUSION: Surgical isolation of the left atrial posterior wall encompassing the ostia of the pulmonary veins is an effective form of treating atrial fibrillation in rheumatic mitral valve disease.

Resultados da ablação cirúrgica por radiofreqüência da fibrilação atrial crônica / Results of the intraoperative radiofrequency ablation of chronic atrial fibrillation

OBJETIVO: A operação de "Cox-Maze III" apresenta alta efetividade para o tratamento da fibrilação atrial (FA) crônica, porém, devido a sua alta complexidade, não é amplamente utilizada. Novas alternativas, que envolvem o uso de fontes de energia, como a radiofreqüência, para criação de lesões transmurais, que substituem as linhas de secção e sutura da técnica de Cox, foram desenvolvidas visando simplificar o procedimento. O objetivo deste estudo é avaliar os resultados do emprego da radiofreqüência intra-operatória para tratamento da FA crônica em pacientes com cardiopatias associadas com indicação de tratamento cirúrgico. MÉTODO: Entre fevereiro de 2002 e março de 2003, 35 pacientes consecutivos portadores de FA crônica foram submetidos à ablação com radiofreqüência intra-operatória, associada a outros procedimentos cirúrgicos. A idade variou de 16 a 69 anos (média = 55,4 anos), sendo 23 (65,7 por cento) pacientes do sexo feminino. RESULTADOS: A ablação foi associada ao tratamento cirúrgico da valva mitral em 29 (82,9 por cento) pacientes e à atriosseptoplastia em seis (17,1 por cento) pacientes. A mortalidade hospitalar foi de 2,8 por cento; vinte e seis (76,4 por cento) pacientes apresentavam-se em ritmo sinusal no momento da alta hospitalar. Após seguimento médio de 11,7 mais ou menos 2,8 meses, a sobrevida foi de 94,2 por cento e 24 (72,7 por cento) pacientes apresentavam-se em ritmo sinusal. CONCLUSAO: A ablação por radiofreqüência intra-operatória demonstrou ser uma técnica segura e eficiente para o tratamento da FA crônica, apresentando índices satisfatórios de reversão para o ritmo sinusal em médio prazo.

Tratamento cirúrgico da fibrilação atrial por isolamento da parede posterior do átrio esquerdo em doentes com valvopatia mitral reumática crônica: um estudo randomizado com grupo controle / Surgical treatment of atrial fibrillation through isolation of the left atrial posterior wall in patients with chronic rheumatic mitral valve disease: a randomized study with control group

OBJETIVO: Determinar a efetividade do isolamento cirúrgico da parede posterior do átrio esquerdo envolvendo os óstios das veias pulmonares, no tratamento da fibrilação atrial de etiologia reumática. MÉTODOS: Estudo prospectivo e randomizado envolvendo portadores de valvopatia mitral reumática, fibrilação atrial persistente com duração > a 6 meses, idade < a 60 anos e diâmetro atrial esquerdo < a 65 mm. Os pacientes foram distribuídos aleatoriamente em dois grupos: tratamento cirúrgico valvar (grupo controle) e tratamento cirúrgico valvar associado ao isolamento da parede posterior do átrio esquerdo mediante técnica de "corte e sutura" (grupo tratado). RESULTADOS: Foram operados 29 indivíduos, sendo que 27 (13 do grupo controle e 14 do grupo tratado), foram acompanhados regularmente. Os pacientes dos dois grupos não diferiram em relação às suas características basais. O tempo de seguimento médio foi de 11,5 meses no grupo controle e de 10,3 meses no grupo tratado. As freqüências cumulativas de pacientes livres de fibrilação atrial foram significativamente maiores no grupo tratado tanto na fase peri-operatória (p= 0,0035) quanto na fase tardia (p= 0,0430). CONCLUSAO: O isolamento cirúrgico da parede posterior do átrio esquerdo envolvendo os óstios das veias pulmonares é uma forma efetiva de tratamento da fibrilação atrial na valvopatia mitral reumática.

Emery-Dreifuss muscular dystrophy: anatomical-clinical correlation (case report)

We report on a man that had weakness of humeroperoneal distribution associated with limited range of motion of the cervical spine and elbows since he was 5 years old . At age 26 he developed tachycardia episodes. A complex arrhythmia was discovered, and a nodal ablation was done with a cardiac pacemaker implanted. The patient had an arrhythmia and sudden death followed this. Emery-Dreifuss muscular dystrophy is a rare recessive X-linked muscular disorder where mixed patterns in electromyography and muscle histology (neurogenic and/or myopathic) have caused nosological confusion. The autopsy findings are here described and correlated to the clinical features in an attempt to better understand the ambiguous findings concerning the process etiology