Flutter Atrial na Síndrome do PRKAG2: Características Clínicas e Eletrofisiológicas / Atrial Flutter in PRKAG2 Syndrome: Clinical and Electrophysiological Characteristics

Resumo Fundamento A síndrome do PRKAG2 é uma rara doença genética autossômico dominante, fenocópia da miocardiopatia hipertrófica, caracterizada pelo acúmulo intracelular de glicogênio. Manifestações clínicas incluem pré-excitação ventricular, hipertrofia ventricular, distúrbio de condução cardíaca e arritmias atriais. Objetivo Comparar características clínicas e eletrofisiológicas observadas em pacientes com flutter atrial, com e sem síndrome do PRKAG2. Métodos Estudo observacional, comparativo de pacientes com flutter atrial: grupo A, cinco pacientes de família com síndrome do PRKAG2; e grupo B, 25 pacientes sem fenótipo da síndrome. O nível de significância foi de 5%. Resultados Todos os pacientes do grupo A apresentaram pré-excitação ventricular e bloqueio de ramo direito; quatro tinham marca-passo (80%). Pacientes do grupo A tinham menor idade (39±5,4 vs. 58,6±17,6 anos, p=0,021), e maior espessura de septo interventricular (mediana=18 vs. 10 mm; p<0,001) e parede posterior (mediana=14 vs. 10 mm; p=0,001). Quatro do grupo A foram submetidos a estudo eletrofisiológico, sendo observada via acessória fascículo-ventricular; em três foi realizada ablação do flutter atrial. Todos os do grupo B foram submetidos à ablação do flutter atrial, sem evidência de via acessória. Observado maior prevalência no grupo B de hipertensão arterial, diabetes mellitus, doença coronariana e apneia do sono, sem diferença estatisticamente significante. Conclusão Portadores da síndrome do PRKAG2 apresentaram flutter atrial em idade mais precoce, e menos comorbidades, quando comparados a pacientes com flutter atrial sem fenótipo da mutação. Importante suspeitar de miocardiopatia geneticamente determinada, como síndrome do PRKAG2, em jovens com flutter atrial, especialmente na presença de pré-excitação ventricular e hipertrofia ventricular familiar.

Abstract Background PRKAG2 syndrome is a rare autosomal dominant disease, a phenocopy of hypertrophic cardiomyopathy characterized by intracellular glycogen accumulation. Clinical manifestations include ventricular preexcitation, cardiac conduction disorder, ventricular hypertrophy, and atrial arrhythmias. Objective To compare the clinical and electrophysiological characteristics observed in patients with atrial flutter, with and without PRKAG2 syndrome. Methods An observational study comparing patients with atrial flutter: group A consisted of five patients with PRKAG2 syndrome from a family, and group B consisted of 25 patients without phenotype of PRKAG2 syndrome. The level of significance was 5%. Results All patients in group A had ventricular preexcitation and right branch block, and four had pacemakers (80%). Patients in group A were younger (39±5.4 vs 58.6±17.6 years, p=0.021), had greater interventricular septum (median=18 vs 10 mm; p<0.001) and posterior wall thickness (median=14 vs 10 mm; p=0.001). In group A, four patients were submitted to an electrophysiological study, showing a fasciculoventricular pathway, and atrial flutter ablation was performed in tree. All patients in group B were submitted to ablation of atrial flutter, with no evidence of accessory pathway. Group B had a higher prevalence of hypertension, diabetes mellitus, coronary artery disease and sleep apnea, with no statistically significant difference. Conclusion Patients with PRKAG2 syndrome presented atrial flutter at an earlier age and had fewer comorbidities when compared to patients with atrial flutter without mutation phenotype. The occurrence of atrial flutter in young individuals, especially in the presence of ventricular preexcitation and familial ventricular hypertrophy, should raise the suspicion of PRKAG2 syndrome.

Saúde Cardiovascular e Fibrilação ou Flutter Atrial: Um Estudo Transversal do ELSA-Brasil / Cardiovascular Health and Atrial Fibrillation or Flutter: A Cross-Sectional Study from ELSA-Brasil

Resumo Fundamento A associação entre o status de saúde cardiovascular ideal ( ideal cardiovascular health ( ICVH) e diagnóstico de fibrilação ou flutter atrial (FFA) foi menos estudado em comparação a outras doenças cardiovasculares. Objetivos Analisar a associação entre o diagnóstico de FFA e métricas e escores de ICVH no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Métodos Este estudo analisou dados de 13141 participantes com dados completos. Os traçados eletrocardiográficos foram codificados de acordo com o Sistema de Minnesota, em um centro de leitura centralizado. As métricas do ICVH (dieta, atividade física, índice de massa corporal, tabagismo, glicemia de jeju, e colesterol total) e escores do ICVH foram calculados conforme proposto pela American Heart Association . Modelos de regressão logística bruta e ajustada foram construídos para analisar associações de métricas e escores do ICVH com diagnóstico de FFA. O nível de significância foi estabelecido em 0,05. Resultados A idade mediana da amostra foi de 55 anos, e 54,4% eram mulheres. Nos modelos ajustados, os escores de ICVH não apresentaram associação significativa com diagnóstico de FFA prevalente [odds ratio (OR):0,96; intervalo de confiança de 95% (IC95%):0,80-1,16; p=0,70). Perfis de pressão arterial ideal (OR:0,33; IC95%:0,1-0,74; p=0,007) e colesterol total ideal (OR:1,88; IC95%:1,19-2,98; p=0,007) foram significativamente associados com o diagnóstico de FFA. Conclusões Não foram identificadas associações significativas entre escores de ICVH global e diagnóstico de FFA após ajuste multivariado em nossas análises, devido, ao menos em parte, às associações antagônicas da FFA com métricas de pressão arterial e de colesterol total do ICVH. Nossos resultados sugerem que estimar a prevenção da FFA por meio de escore de ICVH global pode não ser adequado, e as métricas do ICVH devem ser consideradas separadamente.

Abstract Background The association between ideal cardiovascular health (ICVH) status and atrial fibrillation or flutter (AFF) diagnosis has been less studied compared to other cardiovascular diseases. Objective To analyze the association between AFF diagnosis and ICVH metrics and scores in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods This study analyzed data from 13,141 participants with complete data. Electrocardiographic tracings were coded according to the Minnesota Coding System, in a centralized reading center. ICVH metrics (diet, physical activity, body mass index, smoking, blood pressure, fasting plasma glucose, and total cholesterol) and scores were calculated as proposed by the American Heart Association. Crude and adjusted binary logistic regression models were built to analyze the association of ICVH metrics and scores with AFF diagnosis. Significance level was set at 0.05. Results The sample had a median age of 55 years and 54.4% were women. In adjusted models, ICVH scores were not significantly associated with prevalent AFF diagnosis (odds ratio [OR]:0.96; 95% confidence interval [95% CI]:0.80-1.16; p=0.70). Ideal blood pressure (OR:0.33; 95% CI:0.15-0.74; p=0.007) and total cholesterol (OR:1.88; 95% CI:1.19-2.98; p=0.007) profiles were significantly associated with AFF diagnosis. Conclusions No significant associations were identified between global ICVH scores and AFF diagnosis after multivariable adjustment in our analyses, at least partially due to the antagonistic associations of AFF with blood pressure and total cholesterol ICVH metrics. Our results suggest that estimating the prevention of AFF burden using global ICVH scores may not be adequate, and ICVH metrics should be considered in separate.

Episódios de Alta Frequência Atrial e sua Associação com Eventos Isquêmicos Cerebrais em Pacientes Chagásicos / Atrial High-Rate Episodes and Their Association with Cerebral Ischemic Events in Chagasic Patients

Resumo Fundamento Episódios de alta frequência atrial (EAFAs) estão associados a um risco elevado de eventos isquêmicos cerebrais, porém não existem estudos relacionados com a presença de EAFAs e eventos isquêmicos cerebrais em pacientes chagásicos. Objetivo Investigar a associação entre a presença de EAFAs ≥ 6 minutos e eventos isquêmicos cerebrais em pacientes chagásicos. Métodos Estudo de coorte com pacientes chagásicos, portadores de dispositivos cardíacos eletrônicos implantáveis (DCEIs), acompanhados no ambulatório de arritmias de um hospital universitário, na cidade de Salvador/BA, entre maio de 2016 e junho de 2017. Pacientes com diagnóstico de flutter atrial/fibrilação atrial, com DCEI unicameral e em uso de anticoagulação oral foram excluídos. Foram considerados EAFAs com frequência atrial ≥ 190 batimentos por minuto e duração ≥ 6 minutos (min), e os eventos isquêmicos cerebrais foram identificados por meio de tomografia computadorizada (TC) de crânio. Resultados Os 67 participantes da pesquisa (67,2% do sexo feminino, com idade média de 63,6 ± 9,2 anos) foram acompanhados por 98 ± 28,8 dias e 11,9% dos pacientes apresentaram EAFAs ≥ 6 minutos. A TC de crânio evidenciou eventos isquêmicos cerebrais silenciosos em 16,4% dos pacientes, sendo que, destes, 63,6% haviam apresentado os EAFAs ≥ 6 minutos na análise dos DCEIs. A idade avançada (OR 1,12 [IC 95% 1,03-1,21; p=0,009) e a presença de EAFAs ≥ 6 minutos (OR 96,2 [IC 95% 9,4-987,4; p<0,001]) foram preditores independentes para eventos isquêmicos. Conclusão EAFAs detectados por DCEIs estavam associados à presença de eventos isquêmicos cerebrais silenciosos em pacientes chagásicos. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Abstract Background Atrial high-rate episodes (AHREs) are associated with an increased risk of cerebral ischemic events; however, there are no studies related to the presence of AHREs and cerebral ischemic events in Chagasic patients. Objective To investigate the association between the presence of AHREs ≥ 6 minutes and cerebral ischemic events in Chagasic patients. Methods Cohort study with Chagasic patients with implantable electronic cardiac devices (IECDs), followed at the Arrhythmia Outpatient Clinic of a University Hospital, in the city of Salvador, state of Bahia, Brazil, between May 2016 and June 2017.. Patients diagnosed with atrial flutter / atrial fibrillation, with unicameral IECD and using oral anticoagulation were excluded. AHREs with atrial frequency ≥ 190 beats per minute and duration ≥ 6 minutes (min) were considered, and cerebral ischemic events were identified by computed tomography (CT) of the skull. Results The 67 research participants (67.2% females, mean age 63.6 ± 9.2 years) were followed for 98 ± 28.8 days and 11.9% of the patients had AHREs ≥ 6 min. Skull CT showed silent cerebral ischemic events in 16.4% of the patients, 63.6% of whom had AHREs ≥ 6 min in the analysis of IECDs. Advanced age [OR 1.12 (95% CI 1.03-1.21; p=0.009] and the presence of AHREs ≥ 6 minutes [OR 96.2 (95% CI 9.4-987.4; p <0.001)] were independent predictors for ischemic events. Conclusion AHREs detected by IECDs were associated with the presence of silent cerebral ischemic events in Chagasic patients. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Definition of success criteria for ablation of typical right atrial flutter with a single-catheter approach: A pilot study.

BACKGROUND: The success rate of cavotricuspid isthmus ablation to treat right common flutter is high (up to 95%), but needs bidirectional block confirmation, requiring two or three catheters. AIM: To describe a new pacing technique using a single catheter to ablate and confirm cavotricuspid isthmus block with differential PR interval measurements. METHODS: We included 61 patients from five centres, who were referred for cavotricuspid isthmus ablation. All patients had cavotricuspid isthmus ablation, and the cavotricuspid isthmus block was confirmed by differential pacing using two or three catheters. The new method consisted of measuring the PR interval on the surface electrocardiogram using pacing from the tip of the ablation catheter on the lateral side (lateral delay) and the septal side (coronary sinus ostium) of the cavotricuspid isthmus line (difference=delta PR interval), before and after cavotricuspid isthmus ablation. We analysed the value of the delta PR interval in predicting bidirectional cavotricuspid isthmus block as confirmed by standard methods. RESULTS: Among our patient population (mean age 63±12 years), 39 patients were ablated during sinus rhythm, and 22 during common flutter. Cavotricuspid isthmus block was achieved in all patients but one. Lateral delay and delta PR interval increased significantly after validation of cavotricuspid isthmus block (257±42 vs. 318±50ms and 32±23 vs. 96±22ms, respectively; P<0.0001). A delta PR interval cut-off of ≥70ms had 100% sensitivity and specificity to predict bidirectional cavotricuspid isthmus block. CONCLUSIONS: A single-catheter ablation approach to performing cavotricuspid isthmus line based on surface electrocardiogram PR interval measurement is feasible. After ablation, cavotricuspid isthmus block was systematically obtained when the delta PR interval was>70ms.

Risco de Fibrilação Atrial após Ablação de Flutter Dependente de Istmo Cavo-Tricuspídeo: Vale a Pena Fazer a Ablação da FA Simultaneamente? / Risk of Atrial Fibrillation after Ablation of Cavotricuspid Isthmus-Dependent Atrial Flutter: Is Combined Ablation of Atrial Fibrillation Worthwhile?

Resumo Fundamento A ablação da fibrilação atrial (FA) e do flutter atrial dependente de istmo cavo-tricuspídeo (FLA-ICT) pode ser realizada simultaneamente quando as duas arritmias tenham sido registradas antes do procedimento. Entretanto, a melhor abordagem não é clara quando pacientes com FLA-ICT são encaminhados para ablação sem o registro prévio de FA. Objetivos Avaliar a prevalência e identificar os preditores de ocorrência do primeiro episódio de FA após ablação de FLA-ICT em pacientes sem o registro prévio de FA. Métodos Coorte retrospectiva de pacientes submetidos exclusivamente a ablação por cateter para FLA-ICT, sem registro prévio de FA. As características clínicas foram comparadas entre os grupos em que houve ocorrência de FA pós-ablação de FLA-ICT vs. sem ocorrência de FA. O nível de significância estatística adotado foi de 5%. Na análise de preditores, o desfecho primário avaliado foi ocorrência de FA após ablação de FLA-ICT. Resultados De um total de 227 pacientes submetidos a ablação de FLA-ICT (110 com registro de FA e 33 sem seguimento adequado), 84 pacientes foram incluídos, dos quais 45 (53,6%) apresentaram FA pós-ablação. Não houve variáveis preditoras de ocorrência de FA. Os escores HATCH e CHA2DS2-VASC foram semelhantes nos dois grupos. As taxas de recorrência de FLA-ICT e complicações após a ablação foram de 11,5% e 1,2%, respectivamente. Conclusões A ablação de FLA-ICT é eficaz e segura, mas 50% dos pacientes desenvolvem FA após ablação. Entretanto, ainda é incerto o papel da ablação combinada (FLA-ICT e FA) visando prevenção da ocorrência de FA. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Abstract Background Simultaneous ablation of atrial fibrillation (AF) and cavotricuspid isthmus (CTI)-dependent atrial flutter can be performed when both arrythmias had been recorded before the procedure. However, the best approach has not been defined in case of patients referred for ablation with CTI-dependent atrial flutter, without history of AF. Objectives To assess the prevalence and to identify predictors of the first episode of AF after ablation of CTI-dependent atrial flutter in patients without history of AF. Methods Retrospective cohort of patients with CTI-dependent atrial flutter without history of AF undergoing catheter ablation. Clinical characteristics were compared between patients who developed AF and those who did not have AF after the procedure. Significance level was set at 5%. In the analysis of predicting factors, the primary outcome was occurrence of AF after CTI-dependent atrial flutter ablation. Results Of a total of 227 patients undergoing ablation of CTI-dependent atrial flutter (110 with history of AF and 33 without adequate follow-up), 84 were included, and 45 (53.6%) developed post-ablation AF. The HATCH and CHA2DS2-VASC scores were not different between the groups. Recurrence rate of CTI-dependent atrial flutter and complication rate were 11.5% and 1.2%, respectively, after ablation. Conclusions Although ablation of CTI-dependent atrial flutter is a safe and effective procedure, 50% of the patients developed AF after the procedure. However, the role of combined ablation (CTI-dependent atrial flutter plus AF) aiming at preventing AF is still uncertain. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)

Differential Effectiveness of Landiolol Between Atrial Fibrillation and Atrial Flutter/Atrial Tachycardia Patients With Left Ventricular Dysfunction.

BACKGROUND: Landiolol, an ultra-short acting ß1-selective blocker, is more effective for controlling the heart rate (HR) than digoxin in patients with atrial tachyarrhythmias and left ventricular (LV) dysfunction. The impact of the type of atrial tachyarrhythmias on the effectiveness of landiolol is uncertain. We evaluated the efficacy and safety of landiolol on tachycardiac atrial fibrillation (AF) and tachycardiac atrial flutter/atrial tachycardia (AFl/AT) in patients with reduced LV function. Methods and Results: Seventy-seven patients treated with landiolol were retrospectively analyzed. There were no significant differences in the baseline characteristics between the AF group (n=65) and AFl/AT group (n=12). Despite a higher dosage, the %change in HR from baseline to 12 and 24 h was only -10.2±12.7% and -16.1±19.4% in the AFl/AT group, while it was -28.3±13.2% and -31.3±11.3% in the AF group (P<0.02), respectively. The prevalence of the responders to landiolol treatment was much greater in the AF group than in the AFl/AT group (P<0.001). Alternative treatments such as i.v. amiodarone and electrical cardioversion were required in 83% of the AFl/AT patients. CONCLUSIONS: Landiolol was ineffective in the majority of AFl/AT patients. An alternative management to prevent any worsening of heart failure might be considered in those patients.

Dabigatran and warfarin in nonvalvular atrial fibrillation or atrial flutter in outpatient clinic practice in Brazil / Dabigatrana e varfarina em pacientes com fibrilação atrial não valvar ou flutter em ambulatório especializado no Brasil

ABSTRACT Objectives: To compare warfarin and dabigatran for thromboembolic event prevention in patients with nonvalvular atrial fibrillation or atrial flutter. Methods: This was a retrospective cohort of participants with nonvalvular atrial fibrillation or atrial flutter using either warfarin or dabigatran in a reference center in Brazil. Results: There were 112 patients (mean age 65.5 years), with 55.3% using warfarin. The median duration of follow-up was 1.9 years for warfarin and 1.6 years for dabigatran (p = 0.167). Warfarin patients had a higher median of medical appointments per year (8.3 [6.8-10.4] vs 3.1 [2.3-4.2], p < 0.001) and the frequency of minor bleeding was more than four times higher (17.7% vs 4.0%, p = 0.035). Among patients with prior stroke, those using warfarin had 2.6 times more medical appointments for person-years of follow-up (8.5 vs 3.3). There was no major bleeding or embolic event during follow-up period. Conclusion: The dabigatran group had a lower frequency of minor bleeding and number of medical appointments than the warfarin group, without more embolic events or major bleeding.

RESUMO Objetivos: Comparar varfarina e dabigatrana para prevenção de eventos tromboembólicos em pacientes com fibrilação atrial não valvar ou flutter (FA). Métodos: Coorte retrospectiva de pacientes com FA em uso de varfarina ou dabigatrana em serviço especializado no Brasil. Resultados: Foram avaliados 112 pacientes (média idade 65,5), com 55,3% no grupo varfarina. A mediana do tempo de seguimento foi de 1,9 anos para o grupo varfarina e 1,6 para dabigatrana (p = 0,167). No grupo varfarina houve maior mediana de consultas médicas (CM) por ano (8,3[6,8-10,4] vs. 3,1[2,3-4,2], p < 0,001), com frequência de sangramento menor quatro vezes maior (17,7% vs. 4,0%, p = 0,035). Nos pacientes com acidente vascular cerebral isquêmico prévio, o grupo varfarina teve 2,6 vezes mais CM por pessoas-ano de seguimento (8,5 vs. 3,3). Não houve sangramento maior ou eventos embólicos no período de seguimento. Conclusão: Pacientes em uso de dabigatrana tiveram menor número de sangramento menor e CM que aqueles em uso de varfarina, sem aumentar eventos embólicos ou sangramentos maiores.

Uninterrupted Use of Oral Anticoagulants for the Ablation of Atrial Flutter: A Single Center Cohort of 154 Patients / Uso Ininterrupto de Anticoagulantes Orais na Ablação de Flutter Atrial Istmo-Cavotricuspídeo Dependente: Coorte Unicêntrica de 154 Pacientes

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: 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.