Cardio protected areas in Mexico / Áreas cardioprotegidas en México

Abstract Sudden cardiac death (SCD) remains a major public health problem. Fortunately, with timely access to early defibrillation and high-quality cardiopulmonary resuscitation, an improvement in survival of victims of sudden death has been demonstrated. Efforts made in different countries to create programs for access to public defibrillation have shown great benefits in counteracting mortality associated with this type of event. Hence, we need more programs (such as cardio protected environments) and changes in public health policies. The objective of this work is to raise awareness among the population and decision makers, of importance establishing this type of programs in our country since there continues to be high mortality associated with SCD in our countrymen.

Resumen La muerte súbita cardíaca es todavía un problema importante de salud pública. Por fortuna, con un acceso oportuno a una desfibrilación temprana y una reanimación cardiopulmonar de alta calidad, se ha demostrado una mejoría en la sobrevida de las víctimas de muerte súbita. Los esfuerzos realizados en deferentes países para crear programas de acceso a la desfibrilación pública han mostrado grandes beneficios en contrarrestar la mortalidad relacionada con este tipo de episodios. Se necesitan más programas (como espacios cardioprotegidos) y cambios en las políticas de salud pública. El objetivo de este trabajo es poder concientizar a la población y a los tomadores de decisiones de la importancia de establecer este tipo de programas en el país, ya que aún existe una alta mortalidad relacionada con la muerte cardíaca súbita.

Is there any link between vitamin d and recurrence of atrial fibrillation after cardioversion?

Abstract Introduction: Atrial fibrillation (AF) is the most common chronic arrhythmia in the elderly population. In symptomatic patients, restoration and maintenance of sinus rhythm improve quality of life. Unfortunately, AF recurrence still occurs in a considerable number of patients after cardioversion (CV). In this study, we aimed to evaluate the association between vitamin D (VitD) and AF recurrence after electrical or medical CV. Method: A total of 51 patients who underwent CV for symptomatic AF were included in the study. AF recurrence was defined as an AF pattern in 12-lead electrocardiography (ECG) recording after CV within 6 months or ECG Holter recording of AF lasting more than 30 seconds at 6-month follow-up. Results: Mean vitD level was 21.4 ng/ml in our study population. VitD level was lower in the AF recurrence group than in the non-recurrence group (18 ng/ml vs. 26.3 ng/ml, respectively; P=0.001). Additionally, left atrial diameter was larger in the AF recurrence group compared to the non-recurrence group (4.4 vs. 4.1, P=0.025). Patients with AF recurrence were older than patients without AF recurrence, and, although the prevalence of hypertension is higher in the AF recurrence group, there was no statistically significant difference (P=0.107, P=0.867). Conclusion: In our study, there is a strong association between vitD level and AF recurrence after CV. VitD deficiency might be a predictor of high risk of AF recurrence after CV and vitD supplementation during the follow-up might help the maintenance of sinus rhythm.

Qualidade de vida de indivíduos portadores de dispositivo cardíaco eletrônico implantável / Quality of life of individuals with implantable electronic cardiac device / Calidad de vida de las personas con dispositivo cardiaco electrónico implantable

Objetivo: avaliar a qualidade de vida de indivíduos portadores de dispositivo cardíaco eletrônico implantável. Método: estudo descritivo e transversal realizado com 50 indivíduos em 2018. Utilizou-se o SF-36 e AQUAREL. Resultados: a comorbidade mais frequente foi a hipertensão arterial sistêmica ­ 39 (78%), a cardiopatia de base a bradicardia ­ 18 (36%) e queixas de palpitação e pré-síncope. Predominaram indivíduos com tempo do dispositivo cardíaco eletrônico de até 5 anos ­ 24 (48%), sem troca de gerador ­ 31 (62%). A maioria negou o consumo de bebida alcóolica ­ 47 (94%), de cigarros ­ 44 (88%) e não realiza atividade física regular ­ 34 (68%). No SF-36, o menor escore foi no domínio aspectos físicos (15) e o maior em dor (88,8). No AQUAREL o menor escore foi no domínio dispneia (78,98) e o maior em desconforto (86,54). Conclusão: constatou-se sintomatologia reduzida. Houve associação significativa entre sexo masculino e atividade física. Os indivíduos apresentam melhora da qualidade de vida após a implantação do dispositivo cardíaco.

Objective: to evaluate the quality of life of individuals with implantable electronic cardiac devices. Method: descriptive and cross-sectional study conducted with 50 individuals in 2018. SF-36 and AQUAREL were used. Results: the most frequent comorbidity was systemic arterial hypertension ­ 39 (78%), baseline heart disease bradycardia ­ 18 (36%) and complaints of palpitation and pre-syncope. Individuals with electronic cardiac device time of up to 5 years 24 (48%) predominated, without changing the generator ­ 31 (62%). The majority denied alcohol consumption ­ 47 (94%), cigarettes ­ 44 (88%) and regular physical activity ­ 34 (68%). In the SF-36 the lowest score was in the physical aspects domain (15) and the highest in pain (88.8). In AQUAREL the lowest score was in the domain dyspnea (78.98) and the highest in discomfort (86.54). Conclusion: reduced symptomatology was observed. There was a significant association between males and physical activity. Individuals have improved quality of life after implantation of the cardiac device.

Objetivo: evaluar la calidad de vida de las personas con dispositivos cardíacos electrónicos implantables. Método: estudio descriptivo y transversal realizado con 50 individuos, en 2018. SF-36 y AQUAREL se utilizaron. Resultados: la comorbilidad más frecuente fue la hipertensión arterial sistémica ­ 39 (78%), las cardiopatías subyacentes, bradicardia ­ 18 (36%) y quejas de palpitación y presíncope. Predominan los individuos con tiempo de dispositivo cardíaco electrónico de hasta 5 años ­ 24 (48%) sin cambiar el generador ­ 31 (62%). La mayoría negó el consumo de alcohol ­ 47 (94%), cigarrillos ­ 44 (88%) y actividad física regular 34 (68%). En el SF-36, la puntuación más baja estaba en el dominio de aspectos físicos (15) y la más alta en dolor (88.8). En AQUAREL, la puntuación más baja estaba en el dominio disnea (78,98) y la más alta en malestar (86,54). Conclusión: se observó una sintomatología reducida. Hubo una asociación significativa entre los varones y la actividad física. Los individuos han mejorado la calidad de vida después de la implantación del dispositivo cardíaco.

Fibrilación auricular en cirugía cardíaca / Atrial fibrillation in cardiac surgery

Resumen La fibrilación auricular es la arritmia más frecuente en el periodo posquirúrgico de la cirugía cardíaca. Se relaciona con insuficiencia cardíaca, insuficiencia renal, embolismo sistémico y más días de estancia y mortalidad. La fibrilación auricular en el periodo posquirúrgico de la cirugía cardíaca (FAPCC) suele aparecer en las primeras 48 horas. Los principales mecanismos que producen la aparición y el mantenimiento de la FAPCC son el aumento del tono simpático y la respuesta inflamatoria. Los factores de riesgo adjuntos son la edad avanzada, enfermedad pulmonar obstructiva crónica, enfermedad renal crónica, cirugía valvular, fracción de expulsión del ventrículo izquierdo menor de 40% e interrupción de fármacos bloqueadores β. Existen instrumentos que han demostrado predecir la aparición de FAPCC. El tratamiento profiláctico con bloqueadores β y amiodarona se relaciona con disminución de la aparición de FAPCC. Dada su naturaleza transitoria, se sugiere que el tratamiento inicial de FAPCC sea el control de la frecuencia cardíaca y sólo en caso de que el tratamiento no consiga el retorno al ritmo sinusal está indicada la cardioversión eléctrica. Se desconoce cuál debe ser el seguimiento a largo plazo y sólo se conocen en escasa medida las complicaciones más allá de este periodo. La FAPCC no es una arritmia benigna ni aislada en los pacientes sometidos a operación cardíaca, por lo que la identificación de los factores de riesgo, su prevención y el seguimiento en el ámbito ambulatorio deben formar parte de las unidades dedicadas a la atención y los cuidados de estos pacientes.

Abstract Atrial fibrillation is the most frequent arrhythmia in the postoperative period of cardiac surgery. It is associated with heart failure, renal insufficiency, systemic embolism and increase in days of in-hospital and mortality. Atrial fibrillation in the postoperative period of cardiac surgery (FAPCC) usually appears in the first 48 h after surgery. The main mechanisms involved in the appearance and maintenance of FAPCC are the increase in sympathetic tone and the inflammatory response. The associated risk factors are advanced age, chronic obstructive pulmonary disease, chronic kidney disease, valve surgery, fraction of ejection of the left ventricle less 40% and the withdrawal of beta-blocker drugs. There are instruments that have been shown to predict the appearance of FAPCC. Prophylactic treatment with beta-blockers and amiodarone, is associated with a decrease in the appearance of FAPCC. Given its transient nature, it is suggested that the initial treatment of FAPCC be the heart rate control and only if the treatment does not achieve a return to sinus rhythm, the use of electrical cardioversion is suggested. It is unknown what should be the long-term follow-up and complications beyond this period are little known. FAPCC is not a benign or isolated arrhythmia in patients undergoing cardiac surgery, so the identification of risk factors, their prevention, and follow-up in the outpatient setting, should be part of the units dedicated to the care and care of these patients.

Cardioversión eléctrica como modalidad terapéutica en pacientes con fibrilación auricular / Electric cardioversion as therapeutic modality in patients with atrial fibrillation

Se realizó un estudio descriptivo de 32 pacientes con fibrilación auricular expuestos a cardioversión eléctrica en el Servicio de Cardiología del Hospital General Docente Dr Juan Bruno Zayas Alfonso de Santiago de Cuba, desde Junio del 2013 hasta igual periodo del 2016, a fin de relacionar las variables clínicas y ecocardiográficas con el éxito del proceder. Se halló que en la mayoría de los afectados el choque eléctrico fue exitoso; por tanto, el método empleado resultó seguro y eficaz para tratar la enfermedad y las variables antes citadas se relacionaron con el éxito o fracaso de dicha modalidad terapéutica.

A descriptive study of 32 patients with atrial fibrillation exposed to electric cardioversion in the Cardiology Service of Dr Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba was carried out from June, 2013 to the same period of 2016, in order to relate the clinical and echocardiographic variables with success in the procedure. It was found that in most of the affected cases the electric shock was successful; therefore, the used method was safe and effective to treat the disease and the above mentioned variables were related with the success or failure of this therapeutic modality.

Predictors of Atrial Fibrillation Recurrence in Hyperthyroid and Euthyroid Patients / Preditores de Recorrência de Fibrilação Atrial em Pacientes com Eutireoidismo e Hipertireoidismo

Background: Atrial fibrillation (AF) is the most common arrhythmia in adults, and is encountered in 10-15% of the patients with hyperthyroidism. Unless euthyroidism is restored, pharmacological or electrical cardioversion is controversial in patients with AF who remain hyperthyroid. Objective: The aim of this study was to assess the efficacy of electrical cardioversion and predictors of AF recurrence in hyperthyroid and euthyroid patients. Methods: The study included 33 hyperthyroid (21 males) and 48 euthyroid (17 males) patients with persistent AF. The patients were sedated with intravenous midazolam before undergoing electrical cardioversion delivered by synchronized biphasic shocks. Rates of AF recurrence were recorded. Results: Mean follow-up was 23.63 ± 3.74 months in the hyperthyroid group and 22.78 ± 3.15 months in the euthyroid group (p = 0.51). AF recurred in 14 (43.8%) and 21 (44.7%) patients in each group, respectively (p = 0.93). Multivariate regression analysis in each group showed that AF duration was the only predictor of AF recurrence, with odds ratios of 1.38 (95% confidence interval [CI] = 1.05 - 1.82, p = 0.02) in the hyperthyroid group and 1.42 (95% CI = 1.05 - 1.91, p= 0.02) in the euthyroid group. Conclusion: Rates of long-term AF recurrence were similar in successfully cardioverted hyperthyroid and euthyroid patients. The only predictor of AF recurrence in both groups was AF duration.

Fundamento: A fibrilação atrial (FA) é a arritmia mais comum em adultos e é encontrada em 10-15% dos pacientes com hipertireoidismo. A menos que haja retorno ao eutireoidismo, a cardioversão farmacológica ou elétrica é controversa em pacientes com FA que permanecem com hipertireoidismo. Objetivo: O objetivo deste estudo foi avaliar a eficácia da cardioversão elétrica e os preditores de recorrência de FA em pacientes com hipertireoidismo e eutireoidismo. Métodos: O estudo incluiu pacientes com FA persistente, dos quais 33 (21 homens) apresentavam hipertireoidismo e 48 (17 homens) eutireoidismo. Os pacientes foram sedados com midazolam endovenoso antes de serem submetidos à cardioversão elétrica com choques sincronizados bifásicos. As taxas de recorrência da FA foram registradas. Resultados: O tempo médio de seguimento foi de 23,63 ± 3,74 meses no grupo com hipertireoidismo e 22,78 ± 3,15 meses no grupo com eutireoidismo (p = 0,51). A FA recorreu em 14 (43,8%) e 21 (44,7%) pacientes em cada grupo, respectivamente (p = 0,93). Uma análise de regressão multivariada em cada grupo mostrou que a duração da FA foi o único preditor de recorrência de FA com odds ratios de 1,38 (intervalo de confiança [IC] 95% = 1,05 - 1,82, p = 0,02) no grupo com hipertireoidismo e 1,42 (IC 95% = 1,05 - 1,91, p = 0,02) no grupo com eutireoidismo. Conclusão: As taxas de recorrência da FA a longo prazo foram semelhantes em pacientes com hipertireoidismo e eutireoidismo submetidos com sucesso à cardioversão. A duração da FA foi o único preditor de recorrência da FA em ambos os grupos.

Informe de 3 casos de reanimación extrahospitalaria en la ciudad de Querétaro: Importancia de un sistema integral de atención de emergencias médicas / Prehospital cardiac resuscitation in Queretaro, Mexico: Report of 3 cases. Importance of an integral emergency medical care system

En México, el paro cardiaco que ocurre fuera de las instalaciones hospitalarias representa un problema de salud pública debido a que se estima que es responsable de 33,000 a 150,000 muertes al año. La mortalidad que se informa, en las escasas publicaciones que existen en México, son tan elevadas que incluso llegan al 100% de los eventos, cifras mucho más altas que las informadas en otros países. En la ciudad de Querétaro no se tenían documentados casos de reanimación exitosa en los últimos 5 años, sin embargo, en el 2012 se informaron varios casos en los que la reanimación logró obtener el retorno de la circulación espontánea. Se presentan3 casos con retorno de la circulación espontánea en la escena y pulso a la llegada al hospital. De ellos, 2 egresaron con vida del hospital; pero uno de estos con pobre actividad cerebral. Factores como reanimación cardiopulmonar comunitaria, desfibrilación en los primeros minutos y mejores tiempos de respuesta del sistema de urgencia se relacionan con la supervivencia de las víctimas. Podrían mejorarse los resultados de este poco explorado problema de salud en el contexto mexicano con la mejora de la calidad del servicio de manera continua, con la difusión de estrategias de educación pública en reanimación cardiopulmonar asistida por la persona que está en ese momento, la participación de la policía en la reanimación cardiopulmonar y la desfibrilación, con los programas de acceso público a la desfibrilación y la determinación de indicadores de retroalimentación.

In Mexico, out-of-hospital cardiac arrest is a health problem that represents 33,000 to 150,000 or more deaths per year. The few existent reports show mortality as high as 100% in contrast to some international reports that show higher survival rates. In Queretaro, during the last 5 years there were no successful resuscitation cases. However, in 2012 some patients were reported to have return of spontaneous circulation. We report in this article 3 cases with return of spontaneous circulation and pulse at arrival to the hospital. Two of the patients were discharged alive, one of them with poor cerebral performance category. Community cardiopulmonary resuscitation, early defibrillation and better emergency medical system response times, are related with survival. This poorly explored health problem in Queretaro could be increased with quality and good public education, bystander assisted cardiopulmonary resuscitation, police involvement in cardiopulmonary resuscitation and defibrillation, public access defibrillation programs and measurement of indicators and feedback for better results.

Choques inapropriados em portadores de CDI VR versus DR: meta-análise de ensaios clínicos randomizados / Inappropriate shocks in patients with icds: single chamber versus dual chamber

FUNDAMENTO: Apesar da evolução tecnológica do cardiodesfibrilador implantável, uma das questões que permanece em aberto é sobre o eventual benefício do cardiodesfibrilador implantável de dupla câmara comparativamente ao de câmara única, para diminuir os choques inapropriados. OBJETIVO: Avaliar, em pacientes com cardiodesfibrilador implantável, qual é o tipo de dispositivo que proporciona menor número de choques inapropriados (câmara dupla versus câmara única). MÉTODOS: Meta-análise da literatura publicada, de estudos randomizados, comparando cardiodesfibrilador implantável de câmara dupla ao de câmara única, que tenham, como endpoint avaliado, a ocorrência de choques inapropriados. RESULTADOS: O cardiodesfibrilador implantável de câmara dupla não mostrou benefícios na redução do número de pacientes com choques inapropriados. Pelo contrário, na análise de efeitos fixos, a associação foi tendencialmente favorável ao cardiodesfibrilador implantável de câmara única (OR = 1,53; IC95%: 0,91-2,57), não obstante a ausência de significado estatístico (p = 0,11). Merece destaque a heterogenia observada nos resultados (I2 = 53%), o que motivou a replicação da análise utilizando um modelo de efeitos aleatórios. No entanto, as diferenças significativas permaneceram na ocorrência de choques inapropriados em ambos os grupos (OR = 1,1; IC95%: 0,37-3,31; p = 0,86). Para complementar a análise, procedeu-se à análise de sensibilidade, na qual se verificou que a exclusão de um estudo resultava na mais baixa heterogenia observada (I2=24%) e na associação com os choques inapropriados significativamente favorável ao cardiodesfibrilador de câmara única (OR = 1,91; IC95%: 1,09-3,37; p = 0,27). CONCLUSÕES: Verificou-se a não existência de evidência clara de superioridade de qualquer um dos dispositivos avaliados.

BACKGROUND: Despite the technological evolution of the implantable defibrillator, one of the questions that remains is the possible benefit of the dual chamber versus single chamber implantable cardioverter defibrillator (ICD) in reducing inappropriate shocks. OBJECTIVE: To evaluate which type of device provides fewer inappropriate shocks (dual chamber versus single chamber) in patients with implantable cardioverter defibrillators (ICDs). METHODS: Meta-analysis of randomized studies published in the literature comparing dual-chamber implantable cardioverter defibrillators to single chamber devices which have been known to cause, as an evaluated endpoint, inappropriate shocks. RESULTS: The dual-chamber implantable cardioverter showed no benefit in reducing the number of inappropriate shocks. In fact, the opposite was shown. In the analysis of fixed effects, the association tended to favor single-chamber implantable cardioverter defibrillators (OR = 1.53, CI 95%: 0.91-2.57), despite the absence of statistical significance (p = 0.11). We highlight the heterogeneity observed in the results (I² = 53%), which motivated a replication of the analysis using a model of random effects. However, significant differences remained in the occurrence of inappropriate shocks in both groups (OR = 1.1, 95% CI: 0.37-3.31; p = 0.86). To complement the analysis, we proceeded to perform sensitivity analysis, which showed that the exclusion of a study resulted in the lowest heterogeneity observed (I²=24%) and the association with inappropriate shocks significantly favored the single chamber cardiodefibrillator (OR = 1.91; 95% CI: 1.09-3.37; p = 0.27). CONCLUSIONS: It was determined that there was no clear evidence of superiority of any of the devices evaluated.

Abordagem da fibrilação atrial na sala de emergência / Management of atrial fibrillation in the emergency medical service

A fibrilação atrial motiva a ida do paciente ao pronto-socorro pelos sintomas que provoca. Palpitações, cansaço repentino, incapacidade de realizar esforços habituais são queixas frequentes. Como a incidência dessa arritmia aumenta com a idade, a maioria dos indivíduos que procura as emergências em hospital corresponde àqueles de idade avançada. A conduta com o paciente na sala de emergência depende da forma de apresentação clínica, dos sintomas, da duração da arritmia e do risco de tromboembolismo sistêmico. Em pacientes com instabilidade hemodinâmica, a cardioversão elétrica é obrigatória para restabelecer o ritmo sinusal normal e estabilizar as condições clínicas. No paciente com fibrilação atrial sem repercussão hemodinâmica, apenas com sintomas leves a moderados, a conduta vai desde o controle da frequência ventricular até a cardioversão química ou elétrica eletivas....

Registro prospectivo de arritmias cardíacas em unidade de terapia intensiva / Prospective registry of cardiac arrhythmias in intensive care unit

JUSTIFICATIVA E OBJETIVOS: Arritmias são eventos adversos freqüentes em pacientes gravemente enfermos. O objetivo deste estudo foi avaliar a prevalência, tipo, causas, tratamento e fatores associados às arritmias em unidades de terapia intensiva de clínica médica e geral de um Hospital Universitário. MÉTODO: Estudo prospectivo, observacional e transversal. Durante seis meses, todos os pacientes que desenvolveram arritmia em duas unidades de terapia intensiva (UTI) de hospital universitário terciário foram incluídos. A monitoração contínua com eletrocardiograma (ECG), análise do traçado eletrocardiográfico, gasometria arterial, eletrólitos séricos (K+, Mg2+, Na+, Ca2+), fatores de risco preexistentes, índice APACHE II das 24 horas iniciais, tratamento e desfecho foram registrados. RESULTADOS: Dos 120 pacientes incluídos no estudo, 63 eram do sexo feminino e 57 do sexo masculino. A idade variou de 25 a 93 anos, com média de 65 anos. A hipertensão arterial foi o antecedente mais prevalente em 46 (38,7%) seguido de doença pulmonar obstrutiva crônica (DPOC) em 16 (13,7%). O APACHE II variou de 4 a 39, com média de 20 e risco de médio de mortalidade de 28,9%. Fibrilação atrial (FA) foi mais freqüente em 60 casos (50%), seguida de taquicardia ventricular em 31 (25,7%). Os tratamentos mais administrados foram a amiodarona em 54(45%), cardioversão elétrica em 18 (15%) e reposição de eletrólitos em 13 (11%). A conduta inicial adotada obteve sucesso em 49 (41%). O número de óbitos foi de 37 (31%). CONCLUSÃO: Alterações metabólicas, idade avançada e maior grau de disfunção fisiológica foram fatores comumente presentes em pacientes com arritmia nesta amostra; a fibrilação atrial foi a arritmia mais freqüente.(AU)

BACKGROUND AND OBJECTIVES: Arrhythmias are well-known complications of critical illness. The aim of this study was to evaluate the prevalence, type, causes, treatment and factors associated with arrhythmias in a intensive care units (ICU) of an University Hospital. METHODS: A prospective, observational and cross-sectional study was designed. During 6 months, all patients who developed arrhythmia were included. Continuous electrocardiography (ECG) monitoring, arterial blood gas, serum electrolyte (K+, Mg2+, Na+, Ca2+), preexisting risk factors, APACHE II index to the first 24h, treatment and clinical were record. RESULTS: 120 patients: 63 are female. The age varied from 25 to 93 years, media 65 years. Systemic arterial hypertension (38.7%) and chronic obstructive disease pulmonary (CODP) (13.7%) were the most prevalent risk factors. APACHE II index varied from 4 to 39, media 20 and mean mortality risk of 28.9%. Atrial fibrillation (50%) and ventricular tachycardia (25.7%) were the most frequents arrhythmias. Amiodarone (45%), electrical cardioversion (15%) and serum electrolytes reposition (11%) were the most frequent treatment administered. The initial issues get success rate in 41%. The number of deaths was 37(31%).CONCLUSION: Metabolic alterations, older age end greater degree of physiologic derangement at admission were risk factors for development of arrhythmias. Atrial fibrillation was the most frequent arrhythmia.(AU)

Fibrilación auricular / Atrial fibrillation

Atrial fibrillation is an arrhythmia characterized by no-coordinated atrial contraction that results in an inefficient atrial systole. The clinical classification of atrial fibrillation includes: ocassional, paroxysmal, persistent, and permanent. Multiple mechanisms have been described and accounts for a single ECG manifestation. Treatment should be individualized and has to considered several aspects including age, associated heart disease, and symptoms. Treatment strategies are: rhythm control, rate control, and thromboprophylaxis.

Efeitos da associação da estimulação atrial dinâmica em duplo sítio atrial com atenolol na prevenção da fibrilação atrial recorrente / Effects of the association of dual-site dynamic atrial overdrive and atenolol in preventing recurrent atrial fibrillation

OBJETIVO: Avaliar os efeitos da estimulação atrial otimizada (EAO) (estimulação duplo-sítio atrial, freqüência acima da intrínseca e algoritmo funcional específico) e uso de atenolol, na prevenção da fibrilação atrial (FA) recorrente. Desfecho primário: quantificar a taxa de episódios de FA. Desfechos secundários: qualidade de vida, avaliação de sintomas específicos cardiovasculares, taxa de internações hospitalares, taxa de cardioversões elétricas e farmacológicas e eventos cardíacos adversos. MÉTODOS: Vinte e sete pacientes com FA paroxística recorrente e doença do nó sinusal foram submetidos ao implante de marcapasso duplo-sítio atrial e ventricular e iniciaram com atenolol 100 mg/dia, a seguir foram randomizados em dois grupos, grupo I (3 meses iniciais com EAO e algoritmo especifico ligado e mais 3 com o mesmo desligado) e grupo II (seqüência inversa do grupo I). O modo de estimulação foi DDDR e após 3 meses, foram submetidos à avaliação clínica e eletrônica do sistema de estimulação - mudança automática de modo (AMS), Holter de 24 horas, ecocardiograma e questionário SF-36. Em seguida, foram cruzados e após 6 meses, nova avaliação. RESULTADOS: Pacientes com EAO, quando comparados ao grupo com algoritmo desligado, apresentaram menores taxas de: FA/semana (p<0,001), ativações do AMS (p<0,01), hospitalizações (p<0,001), cardioversões (p<0,001), além de melhores índices dos componentes físico e mental da qualidade de vida. CONCLUSÃO: A terapêutica híbrida, EAO associada ao uso de atenolol, reduziu a taxa de recorrência de FA e proporcionou melhora clínico funcional de pacientes com bradiarritmias sintomáticas.

OBJECTIVE: Evaluate the effects of optimized atrial stimulation - OAS (dual-site atrial pacing, heart rate above the intrinsic rate, and specific functional algorithm), and the use of atenolol in preventing recurrent atrial fibrillation (AF). Primary endpoint: to quantify the rate of AF episodes. Secondary endpoints: assessment of quality of life, specific cardiovascular symptoms, rate of hospital admissions, rate of electrical and pharmacological cardioversions, and adverse cardiac events. METHODS: Twenty-five patients with recurrent episodes of paroxysmal AF and sinus node disease had dual-site atrial and ventricular pacemakers implanted, and were started on atenolol, 100 mg/day. Next, they were randomized to two groups: GROUP I: first three months with OAS and the specific pacing algorithm (DAO) turned on, and three more months with the algorithm off. GROUP II: the inverse sequence to GROUP I. The pacing mode chosen was DDDR, and after three months patients underwent clinical and electronic evaluations of the stimulation system by: automatic mode switch (AMS), 24-hour Holter monitoring, Doppler echocardiogram, and SF-36 questionnaire. Following, a crossover comparison took place, and a new assessment was performed six months later. RESULTS: When compared to the group with the algorithm turned off, OAS patients had lower rates of: AF/week (p < 0.001); AMS activations (p < 0.01); hospitalizations (p < 0.001); cardioversions (p < 0.001), and higher scores on the physical and mental components of quality of life. CONCLUSION: The hybrid therapy adopted, OAS associated with the use of atenolol, reduced the rate of recurrent AF and improved the clinical-functional status of patients with symptomatic bradyarrhythmias.

Cardioversión interna de la fibrilación auricular crónica / Internal cardioversion in chronic atrial fibrillation

The importance of atrial fibrillation has always motivated the search of new treatment alternatives. Internal cardioversion has been proposed as a choice in the treatment of atrial fibrillation, giving rise to the development of atrial defibrillator. We present the case of a 68 years old patient without structural heart disease and with diagnosis of chronic atrial fibrillation of 10 months of evolution. He received treatment with antiarrhythmic drugs and successful electrical external cardioversion, but he relapsed a week later. For this reason, we decided to perform internal cardioversion with an electrocatheter (DAIG) placed in the coronary sinus through the right jugular vein and under light sedation with propofol (2 mg/kg weight). We applied three shocks of 1, 3, and 5 joules, being able to convert to sinus rhythm without complications. The patient continues under treatment with antiarrhythmic agents. Internal cardioversion has shown to be an effective way for the treatment of chronic atrial fibrillation, using a light sedation and low energy level to reestablish the sinus rhythm.

Cardioverter desfibrilador automático implantable en un paciente con cardiopatía chagásica crónica y taquicardia ventricular sostenida / Implantable cardioverter defibrillator in a patient with chronic chagasic cardiopathy and sustained ventricular tachycardia

Presentamos el caso de una mujer de 48 años de edad con cardiopatía chagásica crónica, la que se manifestó con cardiomegalia, insuficiencia cardiaca y sincope debido a taquicardia ventricular sostenida (TVS) de dos morfologías (bloqueo de rama izquierda y de rama derecha del haz de His). Durante el estudio electrofisiológico, se reprodujeron ambos tipos de taquicardia ventricular. Se realizó ablación de la rama derecha del has de His en forma exitosa, debido a la sospecha de reentrada de rama a rama durante la taquicardia con imagen de bloqueo de rama izquierda del haz de His. Continuó presentando episodios de TVS, ahora con imagen de bloqueo de rama izquierda del haz de His, por lo que fue necesaria la colocación de un cardiverter desfibrilador automático implantable. Reportamos el presente caso debido a la poca frecuencia con la que se confirma enfermedad de Chagas en nuestro medio, donde puede ser una causa importante de cardiopatía, en razón de que previamente se ha identificado la existencia del parásito (Tripanosoma cruzi) y su vector (Triatoma) en algunas zonas rurales y suburbanas del estado de Aguascalientes

Desfibrilación auricular transcatéter con baja energía en un caso de fibrilación auricular crónica refractaria / Low energy transcatheter defibrillation in one patient with a refractory atrial fibrillation

Most cases of atrial fibrillation are converted with antiarrhyhmic medications or external electric defibrillation. However, in some refractory patients,an internal transcatheter defibrillation must be attempted. We report a 50 years old male with an atrial fibrillation of one year duration that was refractory to pharmacological treatment and in whom external cardioversion was unsuccessful. After the application of a bifasic shock of 10 joules between a cather in the right atrium and another one located at the coronary sinus, the patient was converted to sinus rhythm. At two months of follow up, the patient continues in sinus rhythm