Abstract Background Intracardiac echocardiography (ICE) allows visualization of cardiac structures and recognition of complications during atrial fibrillation ablation (AFA). Compared to transesophageal echocardiography (TEE), ICE is less sensitive to detecting thrombus in the atrial appendage but requires minimal sedation and fewer operators, making it attractive in a resource-constrained setting. Objective To compare 13 cases of AFA using ICE (AFA-ICE group) with 36 cases of AFA using TEE (AFA-TEE group). Methods This is a single-center prospective cohort study. The main outcome was procedure time. Secondary outcomes: fluoroscopy time, radiation dose (mGy/cm2), major complications, and length of hospital stay in hours. The clinical profile was compared using the CHA2DS2-VASc score. A p-value <0.05 was considered a statistically significant difference between groups. Results The median CHA2DS2-VASc score was 1 (0-3) in the AFA-ICE group and 1 (0-4) in the AFA-TEE group. The total procedure time was 129 ± 27 min in the AFA-ICE group and 189 ± 41 min in the AFA-TEE group (p<0.001); the AFA-ICE group received a lower dose of radiation (mGy/cm2, 51296 ± 24790 vs. 75874 ± 24293; p=0.002), despite the similar fluoroscopy time (27.48 ± 9. 79 vs. 26.4 ± 9.32; p=0.671). The median length of hospital stay did not differ; 48 (36-72) hours (AFA-ICE) and 48 (48-66) hours (AFA-TEE) (p=0.27). Conclusions In this cohort, AFA-ICE was related to shorter procedure times and less exposure to radiation without increasing the risk of complications or the length of hospital stay.

Resumo Fundamento O ecocardiograma intracardíaco (EIC) permite visualizar estruturas cardíacas e reconhecer complicações durante a ablação da fibrilação atrial (AFA). Comparado ao ecocardiograma transesofágico (ETE), o EIC é menos sensível para detecção de trombo no apêndice atrial, porém requer mínima sedação e menos operadores, tornando-o atrativo num cenário de recursos restritos. Objetivo Comparar 13 casos de AFA utilizando EIC (grupo AFA-EIC) com 36 casos de AFA utilizando ETE (grupo AFA-ETE). Método Trata-se de corte prospectiva realizada em um único centro. O desfecho principal foi o tempo de procedimento. Desfechos secundários tempo de fluoroscopia, dose de radiação (mGy/cm2), complicações maiores e tempo de internação hospitalar em horas. O perfil clínico foi comparado pelo escore CHA2DS2-VASc. Um valor de p <0,05 foi considerado uma diferença estatisticamente significativa entre os grupos. Resultados A mediana do escore de CHA2DS2-VASc score foi 1 (0-3) no grupo AFA-EIC e 1 (0-4) no grupo AFA-ETE. O tempo total de procedimento foi de 129 ± 27 min grupo AFA-EIC e 189 ± 41 no AFA-ETE (p<0,001); o grupo AFA-EIC recebeu uma dose menor de radiação (mGy/cm2, 51296 ± 24790 vs. 75874 ± 24293; p=0,002), no entanto, o tempo de fluoroscopia em minutos mostrou-se semelhante (27,48 ± 9,79 vs. 26,4 ± 9,32; p=0,671). As medianas do tempo de hospitalização não se mostraram diferentes, 48 (36-72) horas (AFA-EIC) e 48 (48-66) horas (AFA-ETE) (p=0,27). Conclusão Nesta coorte, AFA-EIC foi relacionado a menores tempos de procedimento e menor exposição à radiação, sem aumentar o risco de complicações ou o tempo de internação hospitalar.

Abstract Background Vitamin K antagonists (VKA) are indicated for the prevention of thromboembolic events and reduction of mortality in patients with atrial fibrillation and patients with valvular prostheses. However, their use is associated with bleeding complications and hospitalizations. Predictors of hospital admission for bleeding in these patients are poorly known. Objectives To define the predictors for hospitalization of VKA users who seek emergency care due to bleeding. Methods Single-center, cross-sectional study, with retrospective analysis of electronic medical records from 03/01/2012 to 02/27/2017. Clinical and laboratory variables were compared between patients who were hospitalized and those who were not. A logistic regression model as used, in which the variables were included using the Backward stepwise method, with a p value of 0.05 as the input criterion, a removal value of 0.20 and a confidence interval of 95%. The p-value was considered statistically significant when <0.05. Results A total of 510 patients with bleeding were included, of whom 158 were hospitalized. Predictors of hospitalization were: INR at supratherapeutic levels (OR 3.45; P <0.01; 95% CI 1.58 - 7.51), gastrointestinal bleeding (OR 2.36; P <0.01; CI 95% 1.24 - 4.50), drop in hemoglobin (OR 6.93; P <0.01; 95% CI 3.67 - 13.07), heart failure (OR 1.96; P 0.01; 95% CI 1.16 - 3.30) and need for blood transfusion (OR 8.03; P <0.01; 95% CI 2.98 - 21.64). Conclusion Drop in hemoglobin, heart failure, INR at supratherapeutic levels, gastrointestinal bleeding and need for blood transfusion were associated with hospitalization. Identification of these factors in the initial evaluation would help to define which patients will demand more intensive care.

Abstract Background In the investigation of cardiac rhythm disorders, a normal electrophysiological (EPS) study is associated with a favorable prognosis. One of the normality criteria is established by conduction intervals within expected range. Objective To establish reference values in EPS for the intracavitary conduction intervals (PA, AH and HV) in a Brazilian population. Methods A retrospective cohort study of the first 1,500 patients submitted to EPS ablation was performed at Instituto de Cardiologia do Rio Grande do Sul, Brazil. The EPS was considered normal if the test was performed for diagnostic purpose; absence of induced arrhythmias; and conduction intervals within the expected range. The REDCap software was used for data collection and management, and the SPSS Statistics 22.0 used for data analysis. Continuous variables were compared with Student's t-test for independent samples and categorical variables with the chi-square test (X 2 ). Values of p ≤ 0.05 were considered significant. Results A total of 124 (8.3%) with EPS considered normal were included; mean age was 52 ± 21 years, and 63 were male. The mean values in milliseconds of PA, AH and HV were 23 ± 9, 88 ± 25 and 44 ± 7, respectively. The PA, AH, and HV percentile ranges were 13 - 25, 81-107 and 40 - 52, respectively. When the patients were divided into three age groups (1 to 18 years, 19 to 64 years and 65 or more), we observed that the group of older patients had significantly higher values of PA, AH and HV compared with younger patients. Conclusion This study showed that intracavitary conduction intervals in a sample of the Brazilian population were similar to previously published studies. Elderly patients tend to have higher values of intracavitary conduction intervals in EPS. Future studies including broader age ranges could enable the acquisition of more reliable and reproducible reference values. (Int J Cardiovasc Sci. 2020; [online].ahead print, PP.0-0)

Abstract Postoperative atrial fibrillation (POAF) after cardiac surgery remarkably remains the most prevalent event in perioperative cardiac surgery, having great clinical and economic implications. The purpose of this study is to present recommendations based on international evidence and adapted to our clinical practice for the perioperative management of POAF. This update is based on the latest current literature derived from articles and guidelines regarding atrial fibrillation.

Abstract Background: Postoperative atrial fibrillation (POAF) after cardiac surgery has great clinical and economic implications. Many attempts have been made to identify risk factors aiming at a better evaluation of prophylactic treatment strategies. Objective: To perform an internal validation of a risk score for POAF. Methods: A prospective cohort of 1,054 patients who underwent myocardial revascularization and/or valve surgery was included. The risk score model was developed in 448 patients, and its performance was tested in the remaining 606 patients. Variables with a significance level of 5% in the cohort were included and subjected to a multiple logistic regression model with backward selection. Performance statistics was performed using the c-statistic, the chi-square and the Hosmer-Lemeshow (HL) goodness-of-fit, Pearson's correlation coefficient. Results: Four variables were considered predictors of outcome: age (≥ 70 years), mitral valve disease, the non-use or discontinuation of beta-blockers and a positive water balance (> 1,500 mL). The ROC curve was 0.76 (95% confidence interval [CI]: 0.72-0.79). The risk model showed a good ability according to the performance statistics - HL test x(2) = 0.93; p = 0.983 and r = 0.99 (Pearson's coefficient). There was an increase in the frequency of POAF with the increase of the score: very low risk = 0.0%; low risk = 3.9%; intermediate risk = 10.9%; and high risk = 60.0%; p < 0.0001. Conclusion: The predictive variables of POAF allowed us to construct a simplified risk score. This scoring system showed good accuracy and can be used in routine clinical practice.

Resumen: La ablación de la fibrilación auricular mediante el aislamiento de las venas pulmonares, es una estrategia ampliamente utilizada en la actualidad. La recurrencia posablación es un problema frecuente. Se han investigado varios predictores de recurrencia con el fin de optimizar la elección del paciente que más se beneficia del procedimiento. Actualmente la evidencia es controvertida, siendo necesarios más estudios al respecto.

Summary: The ablation of atrial fibrillation based on pulmonary veins isolation, is a widely used strategy nowadays. Post ablation recurrence is a frequent problem. Several recurrence predictors have been researched, with the purpose of choosing the patient that would benefit the most from this procedure. Current evidence is controversial and more research is needed.

Abstract Background: The relationship between exercise and atrial fibrillation (AF) is controversial. Objectives: To analyze the effects of physical activity on the incidence of atrial fibrillation using systematic review and meta-analysis. Methods: Systematic review and meta-analysis of studies that relate physical exercise and atrial fibrillation. The following databases were searched: PubMed, BVS Saúde and Cochrane. The following descriptors were used: "atrial fibrillation", "exercise", "physical activity" and "exercise therapy". All prospective, retrospective, cross-sectional and cohort studies were investigated. All statistical analyzes were provided using Review Manager 5.3 to provide the mean difference (MD) and relative risk (RR) ratio with 95% confidence intervals (95% CI). The statistical method of heterogeneity index was used to assess heterogeneity. Level of significance was 5%. Results: Combined analysis of 11 studies totaling 276,323 participants aged between 12 and 90 years did not suggest a significant increase in AF in individuals submitted to physical exercise (RR = 0.914, 95% CI = 0.833-1.003, heterogeneity: p < 0.001). Conclusions: Physical exercise, lato sensu, without stratification by intensity, sex or age does not seem to be associated with an increase of atrial fibrillation.

Resumo Fundamento: O uso de dispositivos cardíacos eletrônicos implantáveis (DCEI) como o cardiodesfibrilador (CDI) e terapia de ressincronização cardíaca (TRC) - é cada vez maior. O número de eletrodos de estimulação e desfibrilação varia de acordo com o dispositivo. A colocação do eletrodo no ventrículo esquerdo aumenta o tempo cirúrgico podendo associar-se a maior morbidade no acompanhamento após alta hospitalar, evento muitas vezes confundível com a gravidade da patologia base. Objetivo: Avaliar a taxa de internação não programada na emergência e óbito após cirurgia de dispositivos implantáveis estratificados pelo tipo de aparelho. Métodos: Estudo de coorte prospectivo analisando 199 pacientes submetidos à implante de dispositivos cardíacos. Os grupos foram divididos de acordo com o tipo de dispositivo: CDI (n = 124) e TRC (n = 75). Estimativas de probabilidades foram analisadas pelo método de Kaplan-Meier de acordo com o desfecho. Valor de p < 0,05 foi considerado significativo nas análises estatísticas. Resultados: A maioria da amostra era do sexo masculino (71,9%) - idade média de 61,1 ± 14,2. A fração de ejeção do ventrículo esquerdo foi similar entre os grupos (TRC 37,4 ± 18,1 vs. CDI 39,1 ± 17,0; p = 0,532). A taxa de visita não programada na emergência relacionada ao dispositivo foi de 4,8% no grupo CDI e de 10,6% no grupo TRC (p = 0,20). A probabilidade de sobrevida relacionada ao dispositivo da variável “óbito” mostrou-se diferente entre os grupos (p = 0,008). Conclusões: Paciente após o implante de TRC apresenta maior probabilidade de mortalidade após o procedimento cirúrgico no seguimento menor que 1 ano. A taxa de visita hospitalar não programada, relacionadas ou não ao implante, não difere entre os grupos.

Abstract Background: The use of Cardiovascular Implantable Electronic Devices (CIED), such as the Implantable Cardioverter Defibrillator (ICD) and Cardiac Resynchronization Therapy (CRT), is increasing. The number of leads may vary according to the device. Lead placement in the left ventricle increases surgical time and may be associated with greater morbidity after hospital discharge, an event that is often confused with the underlying disease severity. Objective: To evaluate the rate of unscheduled emergency hospitalizations and death after implantable device surgery stratified by the type of device. Methods: Prospective cohort study of 199 patients submitted to cardiac device implantation. The groups were stratified according to the type of device: ICD group (n = 124) and CRT group (n = 75). Probability estimates were analyzed by the Kaplan-Meier method according to the outcome. A value of p < 0.05 was considered significant in the statistical analyses. Results: Most of the sample comprised male patients (71.9%), with a mean age of 61.1 ± 14.2. Left ventricular ejection fraction was similar between the groups (CRT 37.4 ± 18.1 vs. ICD 39.1 ± 17.0, p = 0.532). The rate of unscheduled visits to the emergency unit related to the device was 4.8% in the ICD group and 10.6% in the CRT group (p = 0.20). The probability of device-related survival of the variable “death” was different between the groups (p = 0.008). Conclusions: Patients after CRT implantation show a higher probability of mortality after surgery at a follow-up of less than 1 year. The rate of unscheduled hospital visits, related or not to the implant, does not differ between the groups.

Resumo Fundamento: Estudos mostram o benefício da terapia de reperfusão rápida no infarto agudo do miocárdio. No entanto, ainda ocorrem atrasos durante o transporte de pacientes para angioplastia primária. Objetivo: Definir se existe uma diferença no tempo total de isquemia entre pacientes transferidos de outro hospital comparados aos que procuram o serviço espontaneamente. Método: Estudo de coorte histórico, incluindo pacientes atendidos com infarto entre abril de 2014 e setembro de 2015. Os pacientes foram divididos em pacientes transferidos (grupo A) e por demanda espontânea (grupo B). As características clínicas dos pacientes foram retiradas do banco de dados de infarto e o tempo de transferência foi estimado tendo como base o correio eletrônico de acordo com o horário de contato. O nível de significância adotado foi um p < 0,05%. Resultados: A amostra incluiu 621 pacientes, 215 no grupo A e 406 no grupo B. As características populacionais foram semelhantes nos dois grupos. O delta T foi significativamente maior no grupo de pacientes transferidos (385 minutos vs. 307 minutos para o grupo B, p < 0,001) com um atraso decorrente do transporte de 147 minutos. Houve relação significativa da distância de transferência e aumento do tempo de transporte (R = 0,55; p < 0,001). Entretanto, não houve diferença na mortalidade entre os grupos. Conclusão: Pacientes transferidos de outras cidades para tratamento de infarto tem Delta T de transferência acima do recomendado, com tempo ainda mais longo quanto maior a distância a ser percorrida.

Abstract Background: Studies have shown the benefits of rapid reperfusion therapy in acute myocardial infarction. However, there are still delays during transport of patients to primary angioplasty. Objective: To evaluate whether there is a difference in total ischemic time between patients transferred from other hospitals compared to self-referred patients in our institution. Methods: Historical cohort study including patients with acute myocardial infarction treated between April 2014 and September 2015. Patients were divided into transferred patients (group A) and self-referred patients (group B). Clinical characteristics of the patients were obtained from our electronic database and the transfer time was estimated based on the time the e-mail requesting patient's transference was received by the emergency department. Results: The sample included 621 patients, 215 in group A and 406 in group B. Population characteristics were similar in both groups. Time from symptom onset to arrival at the emergency department was significantly longer in group A (385 minutes vs. 307 minutes for group B, p < 0.001) with a transfer delay of 147 minutes. There was a significant relationship between the travel distance and increased transport time (R = 0.55, p < 0.001). However, no difference in mortality was found between the groups. Conclusion: In patients transferred from other cities for treatment of infarction, transfer time was longer than that recommended, especially in longer travel distances.

Resumo Fundamento: Síndrome de Brugada (SBr) é uma condição arrítmica definida por anormalidades do segmento ST-T em derivações V1-V3 associada a risco elevado de arritmias ventriculares e morte súbita. Dados locais quanto às características clínicas dos pacientes com padrão eletrocardiográfico (ECG) típico avaliados por estudo eletrofisiológico (EEF) são escassos. Objetivo: Avaliar pacientes com padrão ECG sugestivo de SBr encaminhados para EEF em um centro especializado. Métodos: Estudo de coorte de casos encaminhados para EEF por padrão ECG compatível com SBr, entre janeiro de 1998 e março de 2017. Resultados: Dos 5506 procedimentos, 35 (0,64%) foram para investigação de SBr. Vinte e cinco (71,42%) eram homens. Idade média 43,89 ± 13,1 anos. Apresentação ECG foi tipo I em 22 casos (62,85%), tipo II em 12 (34,30%) e tipo III em 1 (2,85%). Vinte e três (65,7%) eram assintomáticos, 6 (17,14%) apresentavam palpitações, 5 (14,3%) síncope, 3 (8,6%) história familiar de morte súbita. Estudo eletrofisiológico induziu taquiarritmias ventriculares em 16 casos (45,7%), sendo o período refratário ventricular médio de 228 ± 36 ms. Utilizou-se ajmalina/procainamida em 11 casos (31,4%), sendo o padrão ECG transformado em tipo I em 7 (63,6%). Dezesseis casos (45,7%) receberam cardiodes fibrilador (CDI). Em seguimento médio de 5 anos, 1 dos 16 pacientes (6,25%) com CDI teve terapia apropriada para fibrilação ventricular. Nenhuma morte foi registrada. Outras arritmias ocorreram em 4 (11,4%) casos. Conclusões: Homens são maioria, sendo o padrão ECG tipo I a principal indicação de EEF. Droga classe IA possui alta taxa de conversão do padrão ECG. A taxa de eventos no CDI foi de 6%. (Arq Bras Cardiol. 2018; [online].ahead print, PP.0-0)

Abstract Background: Brugada syndrome (SBr) is an arrhythmic condition characterized by ST-T segment abnormalities in the right precordial leads associated with a high risk of ventricular arrhythmias and sudden death. Local data regarding the clinical characteristics of patients with a typical electrocardiographic (ECG) pattern undergoing electrophysiological study are scarce. Objective: To evaluate patients with an ECG pattern suggestive of SBr referred for electrophysiological evaluation in a specialized center. Methods: Cohort study of patients referred for electrophysiological study because of an ECG pattern compatible with SBr between January 1998 and March 2017. Results: Of the 5506 procedures, 35 (0.64%) were for SBr investigation, 25 of which (71.42%) were performed in men. The mean age was 43.89 ± 13.1 years. The ECG patterns were as follows: type I, 22 (62.85%); type II, 12 (34.30%); and type III, 1 (2.85%). Twenty-three patients (65.7%) were asymptomatic, 6 (17.14%) had palpitations, 5 (14.3%) had syncope, and 3 (8.6%) had a family history of sudden death. Electrophysiological study induced ventricular tachyarrhythmias in 16 cases (45.7%), the mean ventricular refractory period being 228 ± 36 ms. Ajmaline / procainamide was used in 11 cases (31.4%), changing the ECG pattern to type I in 7 (63.6%). Sixteen cases (45.7%) received an implantable cardioverter defibrillator (ICD). In a mean 5-year follow-up, 1 of the 16 patients (6.25%) with ICD had appropriate therapy for ventricular fibrillation. There was no death. Other arrhythmias occurred in 4 (11.4%) cases. Conclusions: Most patients are men, and a type I ECG pattern is the main indication for electrophysiological study. Class IA drugs have a high ECG conversion rate. The ICD event rate was 6%. (Arq Bras Cardiol. 2018; [online].ahead print, PP.0-0)

Resumo Fundamento: O uso ininterrupto de anticoagulação oral (ACO) com antagonistas da vitamina K (AVKs) para procedimentos de eletrofisiologia está sendo cada vez mais recomendado. A prática clínica em nosso serviço é de uso continuado dessas drogas para ablação de flutter atrial. Existem poucas evidências quanto ao uso ininterrupto dos anticoagulantes orais não antagonistas da vitamina K (NOACs) nesse cenário. Objetivos: Comparar as taxas de complicações relacionadas ao uso ininterrupto de diferentes tipos de anticoagulantes orais em pacientes referidos para ablação por flutter atrial (FLA). Métodos: Coorte histórica e unicêntrica dos procedimentos de ablação por FLA realizados no período de novembro de 2012 a abril de 2016. O desfecho primário foi o de ocorrência de complicação hemorrágica ou embólica durante o procedimento. O desfecho secundário foi o de ocorrência de acidente vascular cerebral (AVC) ou acidente isquêmico transitório (AIT) no acompanhamento. O nível de significância estatística adotado foi de 5%. Resultados: Foram incluídas 288 ablações por FLA; 154 foram feitas com uso ininterrupto de ACO (57,8% com AVK e 42,2% com NOAC). A idade média foi de 57 ± 13 anos. A taxa de complicação hemorrágica durante o procedimento foi de 3% em cada grupo (p = NS). A taxa de AVC/AIT foi, respectivamente, de 56/1.000-pessoas-ano no grupo AVK contra zero/1.000-pessoas-ano no grupo NOAC (p = 0,02). Conclusão: Em nossa população não ocorreram complicações hemorrágicas relacionadas ao procedimento com uso de ACO de forma ininterrupta, incluindo NOACs. Houve maior ocorrência de AVC/AIT no seguimento no grupo de pacientes em uso de AVK, contudo essa diferença pode não ser decorrente apenas do tipo de ACO em uso.

Abstract Background: The uninterrupted use of oral anticoagulation (OAC) with vitamin K antagonists (VKAs) for electrophysiology procedures has been more and more recommended. The clinical practice in our service recommends the continuous use of these drugs for atrial flutter ablation. There is little evidence as to the uninterrupted use of non-vitamin K antagonist oral anticoagulants (NOACs) in this scenario. Objective: To compare the rates of complications related with the uninterrupted use of different types of oral anticoagulants in patients referred to atrial flutter (AFL) ablation. Methods: Historical, single-center cohort of ablation procedures by AFL conducted from November 2012 to April 2016. The primary outcome was the occurrence of hemorrhagic or embolic complication during the procedure. The secondary outcome was the occurrence of stroke or transient ischemic attack (TIA) in follow-up. The statistical significance level was 5%. Results: There were 288 ablations per AFL; 154 were carried out with the uninterrupted use of OAC (57.8% with VKA and 42.2% with NOAC). Mean age was 57 ± 13 years. The rate of hemorrhagic complication during the procedure was 3% in each group (p = NS). The rate of stroke/TIA was, respectively, of 56/1,000 people-year in the VKA group against zero/1,000 people-year in the NOAC group (p = 0.02). Conclusion: In our population there were no hemorrhagic complications regarding the procedure of OAC use uninterruptedly, including NOACs. There was higher occurrence of stroke/TIA in the follow-up of the group of patients undergoing VKAs; however, this difference may not only be a result of the type of OAC used.

Resumo Fundamento: A fibrilação atrial é causa de um em cada quatro acidentes vasculares cerebrais, que podem ser prevenidos com anticoagulação oral, uma terapia subutilizada globalmente. Considerando os desafios desse tratamento, instrumentos de saúde móvel para suporte à decisão compartilhada podem melhorar o conhecimento do paciente e otimizar o processo decisório. Objetivo: Desenvolver e avaliar um aplicativo móvel para suporte à decisão compartilhada na profilaxia tromboembólica em fibrilação atrial. Métodos: Foi desenvolvido um aplicativo para ser usado durante a consulta médica, contendo um vídeo sobre fibrilação atrial, calculadoras de escores de risco, gráficos explicativos e orientações sobre os fármacos disponíveis para o tratamento. Durante o desenvolvimento, 30 pacientes interagiram com o aplicativo, que foi avaliado qualitativamente e pela aplicação de um questionário de conhecimento sobre a doença e de uma escala de conflito em tomadas de decisão. Resultados: O número de acertos no questionário de conhecimento sobre a doença teve um aumento significativo após a interação com o aplicativo (de 4,7 ± 1,8 para 7,2 ± 1,0, p < 0,001). A escala de conflito em tomadas de decisão, aplicada após a escolha da terapia com o suporte do aplicativo, resultou em uma média de 11 ± 16/100 pontos, indicando baixo conflito decisório. Conclusões: O uso de um aplicativo móvel durante a consulta sobre anticoagulação em fibrilação atrial melhora o conhecimento sobre a doença, permitindo uma escolha compartilhada com baixo conflito decisório. Mais estudos são necessários para verificar se isso se traduz em benefício clínico.

Abstract Background: Atrial fibrillation is responsible for one in four strokes, which may be prevented by oral anticoagulation, an underused therapy around the world. Considering the challenges imposed by this sort of treatment, mobile health support for shared decision-making may improve patients’ knowledge and optimize the decisional process. Objective: To develop and evaluate a mobile application to support shared decision about thromboembolic prophylaxis in atrial fibrillation. Methods: We developed an application to be used during the clinical visit, including a video about atrial fibrillation, risk calculators, explanatory graphics and information on the drugs available for treatment. In the pilot phase, 30 patients interacted with the application, which was evaluated qualitatively and by a disease knowledge questionnaire and a decisional conflict scale. Results: The number of correct answers in the questionnaire about the disease was significantly higher after the interaction with the application (from 4.7 ± 1.8 to 7.2 ± 1.0, p < 0.001). The decisional conflict scale, administered after selecting the therapy with the app support, resulted in an average of 11 ± 16/100 points, indicating a low decisional conflict. Conclusions: The use of a mobile application during medical visits on anticoagulation in atrial fibrillation improves disease knowledge, enabling a shared decision with low decisional conflict. Further studies are needed to confirm if this finding can be translated into clinical benefit.

Abstract Introduction: Chronic stimulation of the right ventricle with pacemaker is associated with ventricular dyssynchrony and loss of contractility, even in subjects without previous dysfunction. In these patients, there is a debate of which pacing site is less associated with loss of ventricular function. Objective: To compare pacemaker-induced dyssynchrony among different pacing sites in right ventricular stimulation. Methods: Cross-sectional study of outpatients with right ventricle stimulation higher than 80% and preserved left ventricular ejection fraction. Pacing lead position (apical, medial septum or free wall) was assessed through chest X-rays. Every patient underwent echocardiogram to evaluate for dyssynchrony according to CARE-HF criteria: aortic pre-ejection time, interventricular delay and septum/posterior wall delay on M mode. Results: Forty patients were included. Fifty-two percent had apical electrode position, 42% mid septum and 6% free wall. Mean QRS time 148.97±15.52 milliseconds. A weak correlation between the mean QRS width and pre-aortic ejection time (r=0.32; P=0.04) was found. No difference in QRS width among the positions could be noted. Intraventricular delay was lower in apical patients against mid septal (34.4±17.2 vs. 54.3±19.1 P<0.05) - no difference with those electrode on the free wall. No difference was noted in the pre-aortic ejection time (P=0.9). Conclusion: Apical pacing showed a lower interventricular conduction delay when compared to medial septum site. Our findings suggest that apical pacing dyssynchrony is not ubiquitous, as previously thought, and that it should remain an option for lead placement.

Fundamento:A fibrilação atrial e o flutter atrial são responsáveis por um terço das hospitalizações por arritmias, com impacto socioeconômico significativo. Os dados brasileiros a respeito desses atendimentos são escassos.Objetivo:Investigar o subtipo fibrilação atrial ou flutter em pacientes atendidos em emergência em virtude dessas arritmias e comparar os perfis de comorbidades, risco de eventos tromboembólicos e uso de anticoagulantes.Métodos:Estudo transversal retrospectivo, com coleta de dados de prontuário de todos os pacientes atendidos por flutter e fibrilação atrial na emergência do Instituto de Cardiologia do Rio Grande do Sul no primeiro trimestre de 2012.Resultados:Foram incluídos 407 pacientes (356 com fibrilação atrial e 51 com flutter). Os pacientes com fibrilação atrial paroxística eram, em média, 5 anos mais jovens do que aqueles com fibrilação atrial persistente. Comparados àqueles com fibrilação atrial paroxística, os pacientes com fibrilação atrial persistente e flutter tinham maior diâmetro atrial (48,6 ± 7,2 vs. 47,2 ± 6,2 vs. 42,3 ± 6,4; p < 0,01) e menor fração de ejeção (66,8 ± 11 vs. 53,9 ± 17 vs. 57,4 ± 16; p < 0,01). A prevalência de acidente vascular cerebral e insuficiência cardíaca foi maior naqueles com fibrilação atrial persistente e flutter. Os pacientes com fibrilação atrial paroxística e flutter apresentavam mais frequentemente escore CHADS2 de zero em relação àqueles com fibrilação atrial persistente (27,8% vs. 18% vs. 4,9%; p < 0,01). A prevalência de anticoagulação nos pacientes com escore CHA2DS2-Vasc ≥ 2 foi de 40%.Conclusão:A população de nossa amostra teve características demográficas e perfil de comorbidades semelhantes aos de registros ambulatoriais europeus e norte-americanos. Apesar do risco elevado de eventos tromboembólicos, a prevalência de anticoagulação foi baixa, revelando dificuldades na implementação das diretrizes. Estratégias devem ser adotadas para melhorar esses índices.

Introduction:Atrial fibrillation and atrial flutter account for one third of hospitalizations due to arrhythmias, determining great social and economic impacts. In Brazil, data on hospital care of these patients is scarce.Objective:To investigate the arrhythmia subtype of atrial fibrillation and flutter patients in the emergency setting and compare the clinical profile, thromboembolic risk and anticoagulants use.Methods:Cross-sectional retrospective study, with data collection from medical records of every patient treated for atrial fibrillation and flutter in the emergency department of Instituto de Cardiologia do Rio Grande do Sul during the first trimester of 2012.Results:We included 407 patients (356 had atrial fibrillation and 51 had flutter). Patients with paroxysmal atrial fibrillation were in average 5 years younger than those with persistent atrial fibrillation. Compared to paroxysmal atrial fibrillation patients, those with persistent atrial fibrillation and flutter had larger atrial diameter (48.6 ± 7.2 vs. 47.2 ± 6.2 vs. 42.3 ± 6.4; p < 0.01) and lower left ventricular ejection fraction (66.8 ± 11 vs. 53.9 ± 17 vs. 57.4 ± 16; p < 0.01). The prevalence of stroke and heart failure was higher in persistent atrial fibrillation and flutter patients. Those with paroxysmal atrial fibrillation and flutter had higher prevalence of CHADS2 score of zero when compared to those with persistent atrial fibrillation (27.8% vs. 18% vs. 4.9%; p < 0.01). The prevalence of anticoagulation in patients with CHA2DS2-Vasc ≤ 2 was 40%.Conclusions:The population in our registry was similar in its comorbidities and demographic profile to those of North American and European registries. Despite the high thromboembolic risk, the use of anticoagulants was low, revealing difficulties for incorporating guideline recommendations. Public health strategies should be adopted in order to improve these rates.

Fundamento:A ablação com radiofrequência é o tratamento não farmacológico de eleição para arritmias na população pediátrica. Porém, as arritmias e suas causas apresentam características particulares nesta população.Objetivos:Analisar as características epidemiológicas e os achados de estudo eletrofisiológico diagnóstico e ablação com radiofrequência na população pediátrica encaminhada à Eletrofisiologia do Instituto de Cardiologia do Rio Grande do Sul, a fim de caracterizar as suas particularidades.Resultados:Foram realizados 330 procedimentos (9,6% do total de procedimentos) em pacientes com idade inferior a 20 anos (14,33 ± 3,25 anos, variação entre 3 meses e 19 anos), dos quais 201 eram do sexo masculino (60,9%). Foram realizados 108 (32,7%) exames eletrofisiológicos diagnósticos e destes, 48,1% apresentaram anormalidades em seus achados. Ao todo, 219 ablações com radiofrequência foram realizadas (66,3%), obtendo-se sucesso em 84,8%. A presença de feixe acessório foi o achado mais prevalente, responsável por 158 casos (72,1%), seguida de taquicardia por reentrada nodal atrioventricular (16,8%), flutter atrial típico (3,1%) e extrassístole de via de saída de ventrículo direito (2,7%). Três pacientes apresentaram complicações durante a ablação (1,4%). Cardiopatia congênita esteve presente em 51 (15,4%) casos, sendo a comunicação interatrial a mais encontrada (27,4%), seguida de comunicação interventricular (25,4%) e anomalia de Ebstein (17,6%).Conclusão:Estudo eletrofisiológico e ablação com radiofrequência constituem ferramentas eficazes no diagnóstico e tratamento das arritmias na população pediátrica.

Background:Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population.Objective:To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population.Methods:Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013.Results:In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%).Conclusion:Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population.