Electrophysiological study in chagasics with syncope and conduction disorder.

BACKGROUND: Investigation of syncope involves the use of electrophysiological study, particularly in patients with cardiac conduction disorder. There is conflicting evidence about the role of electrophysiological study in patients with Chagas disease. OBJECTIVE: The objective of this study was to evaluate the electrophysiological study findings in patients with Chagas disease and bundle branch block and/or divisional block presenting with syncope. METHODS: This is a retrospective study of patients with Chagas disease and cardiac conduction disorder who underwent electrophysiological study from 2017 to 2021 for the investigation of syncope in a tertiary hospital in São Paulo, Brazil. Those with non-interpretable ECG, known coronary artery disease, and/or other cardiomyopathies were excluded. HV interval and electrophysiological study-induced malignant ventricular arrhythmias data were analyzed. RESULTS: A total of 45 patients (60.2±11.29 years, 57.8% males) were included. The mean HV interval was 58.37 ms±10.68; 22.2% of the studied population presented an HV interval of ≥70 ms; and malignant ventricular arrhythmias were induced in 57.8% patients. The use of beta-blockers and amiodarone (p=0.002 and 0.036, respectively), NYHA functional class≥II (p=0.013), wide QRS (p=0.047), increased HV interval (p=0.02), Rassi score >6.5 (p=0.003), and reduced left ventricular ejection fraction (p=0.031) were associated with increased risk of inducible malignant ventricular arrhythmias. CONCLUSION: More than half of the patients with Chagas disease, syncope, and cardiac conduction disorder have inducible malignant ventricular arrhythmias. Prolonged HV interval was observed in only 20% of population. Wide QRS, prolonged HV, reduced ejection fraction, and higher Rassi score were associated with increased risk of malignant ventricular arrhythmias.

Mat pilates para tratamento da síncope vasovagal por telemedicina / Pilates mat for treating vasovagal syncope via telemedicine

INTRODUÇÃO: A diminuição do retorno venoso é o mecanismo pivotal para o desencadeamento do reflexo vasovagal em pacientes com síncope reflexa. Programas de condicionamento físico (PCF) têm se mostrado promissores para diminuição da recorrência de eventos, possivelmente, pela melhoria do retorno venoso. Entretanto, PCF são caros e pouco acessíveis. O uso do mat Pilates por telemedicina (MPT) pode facilitar a disponibilidade desse tratamento. OBJETIVOS: Avaliar a recorrência de síncope/ pré-síncope em pacientes com síncope vasovagal (SVV) submetidos a MPT; avaliar a segurança do MPT no tratamento da SVV. METODOLOGIA: Foram inclusos pacientes de 18 a 65 anos, com diagnóstico de SVV e pelo menos 1 episódio de síncope ou 2 de pré-síncope nos últimos 3 meses, do ambulatório de síncope da UNIFESP e da seção de eletrofisiologia e arritmias do IDPC, entre março de 2022 e julho de 2023. Foram excluídos pacientes com evidência de doença cardíaca estrutural (DCE), doenças crônicas (DCR) e com impossibilidade de horário. O MPT possuiu 36 sessões síncronas. Foram realizadas 3 sessões semanais, em grupos de até 3 pessoas, com 1 hora de duração. As fichas clínicas com parâmetros hemodinâmicos, eventos adversos e bemestar foram preenchidas a cada sessão. O diário de síncope foi preenchido durante 90 dias. O questionário WHOQOL foi aplicado no início e fim do estudo. Todos os pacientes assinaram o TCLE (CEP: 5.731.062). Foi considerado nível de significância <5%. RESULTADOS: Foram selecionados 229 pacientes, sendo excluídos 27% por DCR ou DCE, 55% por idade, 13% por indisponibilidade, dos quais 11 foram elegíveis e 9 concluíram o estudo. A redução na recorrência de síncope/pré-síncope foi observada após 45 dias de MPT quando comparado com o primeiro período (5,78±2,54 versus 4,00±3,57, p=0,035), gráfico 1. A média do bem-estar foi maior ao término de cada sessão quando comparado ao inicial, entretanto não modificou ao longo do MPT. O WHOQOL não apresentou diferença significativa. A assiduidade foi de 86%. Nenhum evento adverso foi observado durante o protocolo. CONCLUSÃO: O MPT reduziu o número de recorrências de SVV. O uso do MPT foi seguro para o tratamento dos pacientes na amostra estudada.

Alterações da repolarização ventricular estão associadas às anormalidades da função sistólica longitudinal em pacientes com ICFEP / Changes in ventricular repolarization are associated with abnormalities in longitudinal systolic function in patients with HFPEF

INTRODUÇÃO: A insuficiência cardíaca de fração de ejeção preservada (ICFEP) é uma síndrome clínica decorrente de uma diversa combinação de anormalidades fisiopatológicas que confluem na elevação das pressões de enchimento do coração. Dentre tais alterações, alguns fenótipos de pacientes podem apresentar anormalidades da função sistólica do ventrículo esquerdo, a despeito de valores da fração de ejeção dentro dos limites da normalidade. Atualmente, há uma escassez de estudos que avaliam qual o papel das alterações no eletrocardiograma (ECG) na ICFEP e como estas podem contribuir para melhor identificação dos mecanismos que levam à intolerância ao exercício. OBJETIVOS: Avaliar a associação entre alterações da repolarização ventricular com as anormalidades na função sistólica do ventrículo esquerdo em uma população com diagnóstico de ICFEP. MÉTODOS: Estudo observacional transversal de 50 pacientes com diagnóstico de ICFEP confirmado pelo escore europeu HFA-PEFF. A repolarização ventricular foi avaliada através da medida do ângulo espacial QRS-T pelo vetocardiograma (método de Kors) e pelo índice TpicoTfim no ECG. As alterações da função sistólica do ventrículo esquerdo foram avaliadas através da medida do Global Longitudinal Strain (GLS) na ecocardiografia com Speckle Tracking. RESULTADOS: Obteve-se uma amostra de 48 pacientes com idade média de 50 (±5) anos, sendo 67% (33) do sexo feminino. Houve correlação moderada e estatisticamente significante entre o GLS e os parâmetros de repolarização ventricular: TpicoTfim (r=0.42; p<0.001) e o ângulo QRS-T (r= 0.58; p-value<0.001). À análise de regressão linear, obteve-se um ß coeficiente de 0.040 do ângulo QRS-T, denotando que para cada aumento de 25º no ângulo QRS-T, há a uma queda de 1% na função sistólica longitudinal pelo GLS. CONCLUSÃO: Nossos dados sugerem que as alterações da repolarização ventricular identificam pacientes com ICFEP que possuem anormalidades da função sistólica do ventrículo esquerdo apesar de apresentarem valores da fração de ejeção dentro dos limites da normalidade. Particularmente, o ângulo espacial QRS-T se mostrou um parâmetro promissor, superior ao TpicoTfim, e com potencial para ser incluído no arsenal multiparamétrico da avaliação diagnóstica da ICFEP.

Electrophysiological study in chagasics with syncope and conduction disorder

BACKGROUND: Investigation of syncope involves the use of electrophysiological study, particularly in patients with cardiac conduction disorder. There is conflicting evidence about the role of electrophysiological study in patients with Chagas disease. OBJECTIVE: The objective of this study was to evaluate the lectrophysiological study findings in patients with Chagas disease and bundle Branch block and/or divisional block presenting with syncope. METHODS: This is a retrospective study of patients with Chagas disease and cardiac conduction disorder who underwent electrophysiological study from 2017 to 2021 for the investigation of syncope in a tertiary hospital in São Paulo, Brazil. Those with non-interpretable ECG, known coronary artery disease, and/or other cardiomyopathies were excluded. HV interval and electrophysiological study-induced malignant ventricular arrhythmias data were analyzed. RESULTS: A total of 45 patients (60.2±11.29 years, 57.8% males) were included. The mean HV interval was 58.37 ms±10.68; 22.2% of the studied population presented an HV interval of ≥70 ms; and malignant ventricular arrhythmias were induced in 57.8% patients. The use of beta-blockers and amiodarone (p=0.002 and 0.036, respectively), NYHA functional class≥II (p=0.013), wide QRS (p=0.047), increased HV interval (p=0.02), Rassi score >6.5 (p=0.003), and reduced left ventricular ejection fraction (p=0.031) were associated with increased risk of inducible malignant ventricular arrhythmias. CONCLUSION: More than half of the patients with Chagas disease, syncope, and cardiac conduction disorder have inducible malignant ventricular arrhythmias. Prolonged HV interval was observed in only 20% of population. Wide QRS, prolonged HV, reduced ejection fraction, and higher Rassi score were associated with increased risk of malignant ventricular arrhythmias.

CHA2DS2-VASc score, P-wave indexes, and echocardiographic parameters in sinus rhythm patients without valvular heart disease.

OBJECTIVE: The aim of this study was to evaluate the correlation between P-wave indexes, echocardiographic parameters, and CHA2DS2-VASc score in patients without atrial fibrillation and valvular disease. METHODS: This retrospective cross-sectional study included patients of a tertiary hospital with no history of atrial fibrillation, atrial flutter, or valve disease and collected data from June 2021 to May 2022. The exclusion criteria were as follows: unavailable medical records, pacemaker carriers, absence of echocardiogram report, or uninterpretable ECG. Clinical, electrocardiographic [i.e., P-wave duration, amplitude, dispersion, variability, maximum, minimum, and P-wave voltage in lead I, Morris index, PR interval, P/PR ratio, and P-wave peak time], and echocardiographic data [i.e., left atrium and left ventricle size, left ventricle ejection fraction, left ventricle mass, and left ventricle indexed mass] from 272 patients were analyzed. RESULTS: PR interval (RHO=0.13, p=0.032), left atrium (RHO=0.301, p<0.001) and left ventricle diameter (RHO=0.197, p=0.001), left ventricle mass (RHO=0.261, p<0.001), and left ventricle indexed mass (RHO=0.340, p<0.001) were positively associated with CHA2DS2-VASc score, whereas P-wave amplitude (RHO=-0.141, p=0.02), P-wave voltage in lead I (RHO=-0.191, p=0.002), and left ventricle ejection fraction (RHO=-0.344, p<0.001) were negatively associated with the same score. The presence of the Morris index was associated with high CHA2DS2-VASc (p=0.022). CONCLUSION: Prolonged PR interval, Morris index, increased left atrium diameter, left ventricle diameter, left ventricle mass, and left ventricle indexed mass values as well as lower P-wave amplitude, P-wave voltage in lead I, and left ventricle ejection fraction values were correlated with higher CHA2DS2-VASc scores.

CHA2DS2-VASc score, P-wave indexes, and echocardiographic parameters in sinus rhythm patients without valvular heart disease

OBJECTIVE: The aim of this study was to evaluate the correlation between P-wave indexes, echocardiographic parameters, and CHA2DS2-VASc score in patients without atrial fibrillation and valvular disease. METHODS: This retrospective cross-sectional study included patients of a tertiary hospital with no history of atrial fibrillation, atrial flutter, or valve disease and collected data from June 2021 to May 2022. The exclusion criteria were as follows: unavailable medical records, pacemaker carriers, absence of echocardiogram report, or uninterpretable ECG. Clinical, electrocardiographic [i.e., P-wave duration, amplitude, dispersion, variability, maximum, minimum, and P-wave voltage in lead I, Morris index, PR interval, P/PR ratio, and P-wave peak time], and echocardiographic data [i.e., left atrium and left ventricle size, left ventricle ejection fraction, left ventricle mass, and left ventricle indexed mass] from 272 patients were analyzed. RESULTS: PR interval (RHO=0.13, p=0.032), left atrium (RHO=0.301, p<0.001) and left ventricle diameter (RHO=0.197, p=0.001), left ventricle mass (RHO=0.261, p<0.001), and left ventricle indexed mass (RHO=0.340, p<0.001) were positively associated with CHA2DS2-VASc score, whereas P-wave amplitude (RHO=-0.141, p=0.02), P-wave voltage in lead I (RHO=-0.191, p=0.002), and left ventricle ejection fraction (RHO=-0.344, p<0.001) were negatively associated with the same score. The presence of the Morris index was associated with high CHA2DS2-VASc (p=0.022). CONCLUSION: Prolonged PR interval, Morris index, increased left atrium diameter, left ventricle diameter, left ventricle mass, and left ventricle indexed mass values as well as lower P-wave amplitude, P-wave voltage in lead I, and left ventricle ejection fraction values were correlated with higher CHA2DS2-VASc scores.

Correlação entre o escore SAME-TT2R2 e o polimorfismo VKORC1: C. 174-136C>T (RS9934438) como preditores da qualidade da anticoagulação entre pacientes idosos brasileiros usuários de varfarina / Correlation between the SAME-TT2R2 score and the VKORC1:C.174-136C>T (RS9934438) polymorphism as predictors of anticoagulation quality among elderly Brazilian patients using warfarin

INTRODUÇÃO: A varfarina é um anticoagulante utilizado na prevenção e tratamento de doenças tromboembólicas. Nos idosos, a principal indicação é fibrilação atrial. O exame mais utilizado para controle da anticoagulação é o tempo de protrombina, através do cálculo da razão normalizada internacional (RNI), na faixa 2-3, que requerem um monitoramento especial devido a idade, dificuldades na adesão, polimedicação ou comorbidades. Embora seja conhecido que os fatores genéticos influenciam na resposta terapêutica, na maioria dos hospitais a farmacogenética ainda não é considerada no cálculo de ajuste de dose. Portadores do genótipo rs9934438 AA requerem menor dose comparado com genótipo AG ou GG. O escore SAMe- -TT2R2 obtido por meio de algumas variáveis visa predizer quais os pacientes em uso de varfarina atingirão taxas de INR aceitáveis e, por consequência, um tempo na faixa terapêutica (TFT) adequado. Apostolakis, propuseram e validaram o escore SAMe-TT2R2 (S=sexo; A =idade OBJETIVO: Visando estabelecer uma conduta terapêutica personalizada, o presente estudo tem como objetivo avaliar correlação entre o polimorfismo rs9934438 do gene VKORC1 e correlaciona-lo com o escore SAME-TT2R2 na predição da qualidade da anticoagulação em uso de varfarina. MÉTODOS e RESULTADOS: Foram incluídos 29 pacientes, idade de 81,72 (±4,07), de ambos os sexos e em uso de varfarina. A análise do polimorfismofoi realizada através da PCR em tempo real utilizando os reagentes do kit TaqMan™ Sample-to-SNP™ e o sistema de detecção TaqMan® SNP Genotyping Assay. As análises estatísticas foram realizadas utilizando o pacote SPSS v. 16.0 e nível de significância adotado foi de 5% e o Escore SAME-TT2R2 foi calculado após entrevista. Os Escores Chadsvasc2 = 4,34 (±1,17), Hasbled = 2,24 (±0,68) e SAME-TT2R2 = 2,31(±1,28), a dose semanal variou de 10 a 55 mg. Apesar de ser um estudo piloto, com baixo amostra, a distribuição dos genótipos está em equilíbrio gênico, segundo Hardy-Weinberg (AA=24,3%, AG=41,3%, GG= 34,4%). Os portadores do genótipo AA necessitaram de menor dose para atingir a TFT quando comparados aos portadores do genótipo GG: 26,6 versus 39,7 mg/semana, corroborando o resultado do SAME-TT2R2 = 2 no grupo AA comparado ao GG que foi de 3. CONCLUSÃO: Os resultados mostram que o polimorfismo rs9934438 está associado com a dose semanal de varfarina administrada aos pacientes idosos de pelo menos 30% e com correspondência ao Escore SAME-TT2R2 que demostrou um índice menor.

A variabilidade da frequência cardíaca obtida pelo índice triangular é menor em pacientes com fibrilação atrial de pós-operatório de cirurgia cardíaca comparada à fibrilação atrial de pacientes ambulatoriais / Heart rate variability obtained by the triangular index is lower in patients with atrial fibrillation after cardiac surgery compared to atrial fibrillation in outpatients

INTRODUÇÃO: Estudos clínicos demonstram que a fibrilação atrial (FA) de pós-operatório de revascularização miocárdica (FAPO) está associada a mau prognóstico a longo prazo, sendo um marcador de risco futuro para morte cardíaca. O mecanismo envolvido nessa condição ainda não parece claro. Estudo recente demonstrou que pacientes (P) com FA ambulatorial têm pior prognóstico quando o índice triangular (modelo geométrico que avalia o tônus autonômico por meio da variabilidade da frequência cardíaca) está rebaixado (≤14). Nesse índice a presença de ectopias ventriculares é descartada, fornecendo assim, informações mais fidedignas quanto as influências autonômicas sobre o intervalo RR. OBJETIVO: Avaliar o índice triangular de P com FAPO e comparar com o de P com FA ambulatorial sem história de cirurgia de revascularização miocárdica. MÉTODOS: Num período de 24 meses 110 P consecutivos, que foram submetidos a cirurgia de revascularização miocárdica e realizaram Holter por um período de 5 dias após a cirurgia. Dessa população 21 P (19%; 12 ♂, 9♀; média de idade 62±13 anos [variando entre 36 e 64 a]) tiveram FAPO. O grupo FA ambulatorial compreendia 12 P (7 ♂, 5♀; média de idade 58±10 anos [variando entre 38 e 64a]. Foi realizada análise da variabilidade da frequência cardíaca utilizando-se o índice triangular. Para essa determinação dividiu-se o total de intervalos RR consecutivos pelo número de intervalos RR agrupados com diferença máxima de 8 ms entre si durante períodos de FA em ambos os grupos. RESULTADOS: O índice triangular esteve abaixo de 14 em 13/21P (62%; mediana = 13) dos P com FAPO enquanto no grupo de FA ambulatorial esteve abaixo em apenas 1/12 P (8%; mediana = 33) (X2 = 6,913; p=0,009). O valor do índice triangular dos P com FAPO foi de 14,3±6,3 e do grupo FA ambulatorial de 33,6±10 (p<0,0001). CONCLUSÕES: a) o índice triangular foi significativamente menor em P com FAPO em comparação com os P com FA ambulatorial; b) esses achados indicam que a menor variabilidade dos intervalos RR pode ser uma explicação para evolução mais desfavorável dessa população; c) estudos clínicos com seguimento ambulatorial de longo prazo podem confirmar esses achados.

Taquicardia ventricular fascicular em escolar. A importância do diagnóstico e do teste ergométrico na resposta terapêutica do paciente. Descrição de um caso / Fascicular ventricular tachycardia in a schoolchild. The importance of diagnosis and exercise testing in the patient's therapeutic response. Description of a case

INTRODUÇÃO: As arritmias ventriculares habitualmente são mais graves que as arritmias supraventriculares e tem menor penetrância quanto a aquisição de conhecimento junto as equipes pediátricas devido a sua maior raridade. Isto propicia equívocos diagnósticos e terapêuticos em casos específicos como nas taquicardias fasciculares (TF), de complexos QRS relativamente estreitos, o que em muitas vezes prejudica o paciente interferindo diretamente em sua qualidade de vida. As TF se manifestam em sua quase totalidade como arritmias de coração estruturalmente normal, desencadeada pelo esforço e com morfologia eletrocardiográfica bem definida com positividade em V1, eixo desviado para esquerda e em alguns casos presença de ondas p dissociadas. OBJETIVO: Descrever aspectos clínicos um caso de escolar de 8 anos com quadro de taquicardia induzida pelo esforço com padrão TF inicialmente abordada como taquicardia supraventricular. DESCRIÇÃO DO CASO: Menina de 8 anos portadora de taquicardia desencadeada pelo esforço com idas previas ao PS pediátrico e diagnostico de taquicardia supraventricular. Inicialmente recebeu amiodarona para o tratamento, entretanto houve manutenção do quadro de taquicardia com auto limitação da menor na tentativa de controle dos episódios de taquicardia. Solicitado teste ergométrico com fácil desencadeamento de taquicardia de complexos QRS relativamente estreito (110 ms) e morfologia positiva em V1 e com desvio do eixo para esquerda. A análise do D2 longo observa-se a presença de dissociação AV e fusão, confirmando o diagnóstico de TF. Optado por internação da menor e redução da dose de amiodarona e introdução de verapamil com progressão até 4,3 mg kg dia com melhora dos episódios de taquicardia. Realizado teste ergométrico de controle havendo indução de taquicardia apenas com FC superior a 170 bpm em ritmo sinusal. Paciente referiu também melhora importante dos sintomas em curto prazo de avaliação (2 semanas). Está em programação para ablação por radiofrequência com abordagem combinada retro aórtica e transeptal. CONCLUSÃO: 1) o diagnóstico de TF é baseado no conhecimento do padrão eletrocardiográfico típico 2) o tratamento especifico com Verapamil (arritmia verapamil-sensível) permite a melhora da qualidade de vida enquanto se aguarda o tratamento definitivo com ablação 3) O teste ergométrico pode servir de guia para terapêutica e orientação da FC máxima a ser atingida pela paciente antes de se desencadear a crise de TF.

The accuracy of the Stroke Risk Analysis (SRA) system for predicting atrial fibrillation in patients in the postoperative period of myocardial revascularization.

INTRODUCTION: Postoperative myocardial revascularization atrial fibrillation (POAF) is a clinical complication that affects about 30% of patients and its mechanisms of origin are still poorly understood. This fact makes it difficult to identify the patient at greatest risk for this arrhythmia. This mission seems evident due to the complications it entails, including longer hospital stays, risk of stroke, heart failure, and death. There are reports of preoperative clinical aspects inherent to the patient's condition, such as gender and age, and discontinuation of beta-blockers as risk factors. In addition, additional information obtained by electrocardiogram, echocardiogram, and blood count data, for example, present only modest predictive results. The analysis of heart rate and heart rate variability obtained by the Stroke Risk Analysis System (SRA) is a technique used to predict ambulatory atrial fibrillation (AF), using recordings of only one hour showing good accuracy. This system, however, has not yet been used to predict the emergence of POAF. The rationale for its use is based on the suspicion that the emergence of POAF is strongly related to sympatho-vagal imbalance and the increase in atrial ectopia, that is, changes in heart rhythm, the main variables analyzed by the SRA algorithm. OBJECTIVE: To assess the accuracy of the SRA to identify patients at risk of having POAF after coronary artery bypass graft surgery (CABG). METHOD: 114 consecutive patients with coronary artery disease underwent coronary artery bypass grafting between the years 2015 and 2018. Between the first and fifth postoperative days, they underwent continuous electrocardiographic monitoring using the Holter system for cardiac rhythm analysis. Patients were divided into two groups: Group I was formed of those with POAF and Group II included patients without POAF. The tracings obtained by Holter were reanalyzed using the CardioManager®/Cardios program, converted and divided into one-hour sections using the SRA®/Cardios and Geratherm Converter program and submitted to the SRA-Apoplex medical/Geratherm® analysis algorithm. The SRA identifies three possibilities for classifying patient risk: a) Risk 0: patient in sinus rhythm; b) Risk 1: patient at increased risk for paroxysmal AF; c) Risk 2: patient with AF already present. For Group I, SRA were considered positive when Risks 1 and 2 were identified. For Group II, those identified as Risk 0 were considered negative SRA. RESULTS: POAF occurred in 33/114 patients (28%). The sensitivity, specificity, positive predictive value, and negative predictive value of the SRA to identify patients with POAF were 69%, 84%, 69%, and 82%, respectively; the positive and negative likelihood ratios, in addition to the accuracy of the SRA were, respectively, 4.3%, 0.36%, and 79%. A subanalysis of the results of the day on which AF occurred was performed on the records obtained in the first three hours of recording and up to three hours before the appearance of POAF. In the first period, the SRA was able to predict POAF in 57% of cases, while in the second period, the system identified the arrhythmia in 83% of cases. CONCLUSIONS: a) The SRA presents good accuracy to predict POAF; b) its accuracy is moderate in the first three hours of recording; c) the accuracy increases significantly near the beginning of POAF; d) these findings indicate that electrophysiological changes that precede POAF are acute, occurring a few hours before the event and are identified by the SRA algorithm.

The accuracy of the stroke risk analysis (SRA) system for predicting atrial fibrillation in patients in the postoperative period of myocardial revascularization

INTRODUCTION: Postoperative myocardial revascularization atrial fibrillation (POAF) is a clinical complication that affects about 30% of patients and its mechanisms of origin are still poorly understood. This fact makes it difficult to identify the patient at greatest risk for this arrhythmia. This mission seems evident due to the complications it entails, including longer hospital stays, risk of stroke, heart failure, and death. There are reports of preoperative clinical aspects inherent to the patient's condition, such as gender and age, and discontinuation of beta-blockers as risk factors. In addition, additional information obtained by electrocardiogram, echocardiogram, and blood count data, for example, present only modest predictive results. The analysis of heart rate and heart rate variability obtained by the Stroke Risk Analysis System (SRA) is a technique used to predict ambulatory atrial fibrillation (AF), using recordings of only one hour showing good accuracy. This system, however, has not yet been used to predict the emergence of POAF. The rationale for its use is based on the suspicion that the emergence of POAF is strongly related to sympatho-vagal imbalance and the increase in atrial ectopia, that is, changes in heart rhythm, the main variables analyzed by the SRA algorithm. OBJECTIVE: To assess the accuracy of the SRA to identify patients at risk of having POAF after coronary artery bypass graft surgery (CABG). METHOD: 114 consecutive patients with coronary artery disease underwent coronary artery bypass grafting between the years 2015 and 2018. Between the first and fifth postoperative days, they underwent continuous electrocardiographic monitoring using the Holter system for cardiac rhythm analysis. Patients were divided into two groups: Group I was formed with POAF and Group II included patients without POAF. The tracings obtained by Holter were reanalyzed using the Cardio Manager/Cardios program, converted and divided into one-hour sections using the SRA/Cardios and Geratherm Converter program and submit ted to the SRA-Apoplex medical/Geratherm analysis algorithm. The SRA identifies three possibilities for classifying patient risk: a) Risk 0: patient in sinus rhythm; b) Risk 1: patient at increased risk for paroxysmal AF; c) Risk 2: patient with AF already present. For Group I, SRA were considered positive when Risks 1 and 2 were identified. For Group II, those identified as Risk 0 were considered negative SRA. RESULTS: POAF occurred in 33/114 patients (28%). The sensitivity, specificity, positive predictive value, and negative predictive value of the SRA to identify patients with POAF were 69%, 84%, 69%, and 82%, respectively; the positive and negative likelihood ratios, in addition to the accuracy of the SRA were, respectively, 4.3%, 0.36%, and 79%. A sub analysis of the RESULTS: of the day on which AF occurred was performed on the records obtained in the first three hours of recording and up to three hours before the appearance of POAF. In the first period, the SRA was able to predict POAF in 57% of cases, while in the second period, the system identified the arrhythmia in 83% of cases. CONCLUSIONS: a) The SRA presents good accuracy to predict POAF; b) its accuracy is moderate in the first three hours of recording; c) the accuracy increases significantly near the beginning of POAF; d) these findings indicate that electrophysiological changes that precede POAF are acute, occurring a few hours before the event and are identified by the SRA algorithm.

Use of cilostazol in young patients with vagotonia related to bradycardia: description of 4 cases in adolescence

INTRODUCTION: Bradycardias in adolescents can be generated by diseases of the conduction tissue or by external influence (vagal tone, for example). Symptomatic Vagotonia may prompt healthcare professionals to early implant artificial cardiac stimulation devices. However, the transient aspects of vagotonia in the hebiatric population lead to the risk of over-indication. Phosphodiesterase inhibitors, such as cilostazol, can help with transient dysfunction by increasing the conduction of sodium channels in the depolarization phase (funny channels) of automatic cells. OBJECTIVES: To describe 4 cases of adolescents with bradycardia of extrinsic origin undergoing evaluation for permanent pacemaker implantation undergoing oral therapy with cilostazol. METHODS: Four adolescents (12, 15, 16, and 18 years old) were evaluated (3 patients were male and 1 female) with bradycardia of extrinsic origin - vagotonia (responsive to ergometry or atropine) and underwent drug therapy with cilostazol after ruling out the presence of ventricular arrhythmias caused by triggered activity. One patient had congenital heart disease (univentricular heart disease late PO of total cavopulmonary - single left ventricle without atrial isomerism). The others had structurally normal hearts. Ventricular function was preserved in all patients. All had sinus pauses longer than 2.5 s and paroxysmal atrioventricular block. The initial dose was 50mg/day, with dose progression up to 100 mg every 12 hours as the therapeutic goal. RESULTS: Only the patient with congenital heart disease was maintained on the initial dose due to a good Holter response and important improvement in oxygen saturation. There was a reduction of more than 90% in pauses with an average increase in HR without exacerbating periods of tachycardia on Holter monitoring (performed biweekly). After using cilostazol, heart rate variability in the time and frequency domains showed an improvement in the LF/HF ratio in all cases and a reduction in pNN50 in 75% of patients. There was no change in liver or kidney function while using the medication. All remained asymptomatic during follow-up from 3 months to 4 years. CONCLUSION: 1) The use of cilostazol reduces the parasympathetic/sympathetic imbalance with cilostazol in symptomatic pubescent adolescents may prevent pacemaker implantation in patients with transient vagotonia.

Resolution of atrial fibrillation after radiofrequency septal ablation: case report

Atrial fibrillation is a multifactorial disease. The incidence of atrial fibrillation in cardiomyopathy is underestimated, and clinical and interventional treatment is faced with expectations of high recurrence rates. According to the new treatment guidelines for atrial fibrillation, the control of comorbidities must go hand in hand with symptom control and prevention of embolic events. Although surgical treatment of septal reduction (myectomy)has not reduced the incidence of atrial fibrillation, we do not yet know how new gradient reduction approaches may impact AF burden. Here, we have the first case report of atrial remodeling following radiofrequency septal ablation, reducing the burden of atrial fibrillation. CASE REPORT: Woman, 64 years old, with hypertrophic obstructive cardiomyopathy and paroxysmal atrial fibrillation, three symptomatic crises in the last year using amiodarone 400 mg per day and metoprolol 100 mg. Ejection Fraction 70%m septum 18 mm, LA 42mm, gradient 77 mmHg and presence of systolic anterior movement (SAM) with moderate mitral reflux. Ablation of the interventricular septum via transseptal and retro aortic routes was performed according to the protocol with gradient reduction and septal hyperrefringence. During the manipulation of the catheter in the left atrium, a new moderate pericardial effusion was observed, and it was decided not to perform concomitant pulmonary vein isolation (initial planning). Pericardial drainage and heparinization reversal were performed, with discharge from the ICU in 3 days. There was an improvement in symptoms over the first three months­and a progressive reduction of mitral insufficiency and SAM. Amiodarone was withdrawn after the third month, and there were no new arrhythmic events one year after septum ablation. At the end of one year, the echocardiogram showed no evidence of SAM or ventricular gradient, ejection fraction of 58%, septum of 12 mm and LA 36 mm. Thus, radiofrequency septal ablation allowed atrial remodeling and reduced AF burden. The long-term effects of this therapy can be beneficial when there is no symptom control with usual strategies.

24-hour Holter as a method for correlating symptoms and arrhythmic events

INTRODUCTION: Complaints of palpitations are widespread in clinical practice and, in most cases, require 24-hour Holter or prolonged monitoring. When the symptom is due to an arrhythmia, the possibility of obtaining an electrocardiographic record of the moment of the complaint is very useful and can help direct therapy. OBJECTIVE: To evaluate the relationship between symptoms and arrhythmic events in a large 24-hour Holter sample. METHODS: 6,585 24-hour Holters were selected in a tertiary cardiology hospital in 2018. Of these, 483 (7.33%) were excluded. They did not contain information about symptoms in the report, and 363 (5.5%) because they did not have data from the event diary. The remaining 5,739 exams were analyzed for the relationship between symptoms (data provided by the patient) and electrocardiographic changes. Results: Of the 5,739 Holters and event diaries analyzed, 46% were from male individuals. The average age was 58.2 years. Of the total sample, 93.18% (5348 patients) did not report symptoms in the event diary. However, 68.6% (3668 patients) of the exams contained significant changes. The main changes were frequent extrasystoles (>30/h) and non-sustained tachycardias. Frequent atrial ectopy and frequent ventricular ectopy occurred in 913 and 1412 patients, respectively. Ventricular tachycardia and supraventricular tachycardia occurred in 1,879 and 1,166 patients. Symptoms were reported by 391 patients (6.81%). The sensitivity for positive clinical ECG correlation was 24.8%. Men reported fewer symptoms (31% of reports), with a lower rate of positive clinical correlation (33% among men). In women, the clinical correlation was 66%. CONCLUSION: 1) Although sensitive for detecting asymptomatic arrhythmic events, the traditional 24-hour Holter has significant limitations, even in populations with known arrhythmias, correlating symptoms with electrocardiographic changes. The high rate of altered exams without reporting symptoms may reflect the limitation of applying the event diary used. 2) More accessible and practical monitoring methods could reduce the discrepancy between arrhythmic events and symptoms, facilitating doctors' understanding of the factors that motivate patients to seek health services.

Probable atrioventricular reentry tachycardia (Node to Node) in a patient with right atrial isomerism in the immediate postoperative period of palliative surgery

INTRODUCTION: Patients with right atrial isomerism present duplicity of intracardiac structures, such as atrioventricular nodes. They thus present tachycardia of supraventricular reentry and responsive to adenosine therapy. In the postoperative period of palliative surgeries, the presence of tachycardia in these patients is not always related to junctional ectopic foci. OBJECTIVE: To describe a case of a patient with right atrial isomerism associated with complex heart disease with tachycardia maintained by AV reentry due to probable accessory AVN. Case report: 6-year-old girl with right atrial isomerism, total AV septal defect with vessels in transposition and anomalous intracardiac pulmonary vein drainage corrected at six months of age. She underwent central shunt replacement at 6 years of age. She has pulmonary hypertension, which requires palliative surgical support. After replacing the central shunt in the immediate postoperative period, she presented tachycardia with narrow QRS complexes and PR greater than RP with QRS onset at the beginning of the P wave of 120 ms and HR 188bpm. She had a BP of 65x40 mmHg and a capillary refill time of 5 seconds. Following ECG analysis and the 2020 PALS algorithm, adenosine was performed with immediate reversion to sinus rhythm and recovery of hemodynamic patterns. CONCLUSION: 1) Although tachycardias due to AV reentry are rarer in patients with right atrial isomerism due to Node to Node reentry, they should always be considered; 2) The use of adenosine in hemodynamically unstable supraventricular tachycardias should be the first choice when available; 3) electrocardiographic recording of the crisis allows for a more assertive diagnosis and more effective short- and long-term treatment.

Cardioinhibitory syncope 2b with 48-second pause in a patient with Down Syndrome and corrected AV septal defect: description of the case and therapeutic plan

INTRODUCTION: Syncope usually begins in adolescence. Approximately 20% of the population experiences their first episode of fainting between the ages of 10 and 20. Although extremely distressing, these are not always investigated. Only 25 to 50% of patients are evaluated in health services. However, some cases deserve treatment due to the risk of events and require specialized monitoring, including monitoring the indication of pacemaker devices (PM) in case of refractoriness to clinical treatment. This occurs in some cases of syncope with a neuromediated pattern of the cardioinhibitory type with pause (cardioinhibitory syncope 2b in the Tilt Test). OBJECTIVE: To describe the case of a post-pubertal patient with Down Syndrome and recent onset recurrent Syncope with a positive tilt test (TT) (2b response). CASE DESCRIPTION:13-year-old female patient with Down Syndrome with a total AV Septal defect in the post-operative phase of total correction with good surgical results. Recurrent syncope with prodromes (abdominal pain and pallor). She has Holter monitoring without arrhythmic changes and an echocardiogram with RVEF at the lower limit of normality. ECG analysis shows signs of the right anterior superior divisional block. She was submitted for evaluation by TT. She had performed a passive tilt protocol at 70 degrees without sensitization. After 5 minutes of rest, she was titled and remained stable for 7 minutes. In the eighth minute of tilting, she presented abdominal pain, followed by syncope with cardioinhibitory response 2b and a 48-second pause despite returning to the Trendelenburg position (-30 degrees). There was a return of the heartbeat with immediate recovery of the level of consciousness. Clinical treatment began with guidance on increasing water intake, suspending triggering factors (prolonged orthostasis, hot environments, for example) and maintaining strict monitoring to assess refractoriness and the need for PM indication. CONCLUSION: 1) Neuromediated syncope is particularly common during adolescence, especially after the growth spurt; 2) cardioinhibitory responses can appear suddenly and have significant repercussions. Despite this fact, clinical treatment must always be prioritized; 3) The patient must be monitored for recurrences and refractoriness to clinical therapy for the precise indication of PM in patients with cardioinhibitory syncope 2b with long pauses refractory to general measures.

Fascicular ventricular tachycardia in a schoolchild: the importance of diagnosis and exercise testing in the patient's therapeutic response - description of a case

INTRODUCTION: Ventricular arrhythmias are usually more severe than supraventricular arrhythmias and are less penetrant in acquiring knowledge among pediatric teams due to their greater rarity. This leads to diagnostic and therapeutic errors in specific cases, such as fascicular tachycardia (FT), with relatively narrow QRS complexes, which often harms the patient, directly interfering with their quality of life. FT manifests almost entirely as arrhythmias of a structurally normal heart triggered by effort and with well-defined electrocardiographic morphology with positivity in V1, axis deviated to the left, and, in some cases, the presence of dissociated P waves. OBJECTIVE: To describe the clinical aspects of a case of an 8-year-old schoolgirl with effort-induced tachycardia with FT pattern initially treated as supraventricular tachycardia. Case description: 8-year-old girl with tachycardia triggered by exertion with previous visits to the pediatric ER and diagnosed with supraventricular tachycardia. Initially, he received amiodarone for treatment. However, the tachycardia condition continued with minor self-limitation in an attempt to control the tachycardia episodes. An exercise test was requested, with easy onset of tachycardia with relatively narrow QRS complexes (110 ms) and positive morphology in V1 and axis deviation to the left. Analysis of long D2 shows the presence of AV dissociation and fusion, confirming the diagnosis of FT. It was decided to hospitalize the minor and reduce the dose of amiodarone, and introduce verapamil with progression up to 4.3 mg/kg/day with improvement in tachycardia episodes. A control exercise test was performed, and tachycardia was induced only with an HR greater than 170 bpm in sinus rhythm. The patient also reported significant symptom improvement within a short evaluation period (2 weeks). Radiofrequency ablation is being scheduled with a combined retro-aortic and transseptal approach. CONCLUSION: 1) The diagnosis of FT is based on knowledge of the typical electrocardiographic pattern; 2) Specific treatment with Verapamil (verapamil-sensitive arrhythmia)allows for an improvement in quality of life while awaiting definitive treatment with ablation; 3) The exercise test can serve as a therapeutic guide and guide the maximum HR to be reached by the patient before triggering FT crisis.

Electrophysiological study in chagasics with syncope and conduction disorder

SUMMARY BACKGROUND: Investigation of syncope involves the use of electrophysiological study, particularly in patients with cardiac conduction disorder. There is conflicting evidence about the role of electrophysiological study in patients with Chagas disease. OBJECTIVE: The objective of this study was to evaluate the electrophysiological study findings in patients with Chagas disease and bundle branch block and/or divisional block presenting with syncope. METHODS: This is a retrospective study of patients with Chagas disease and cardiac conduction disorder who underwent electrophysiological study from 2017 to 2021 for the investigation of syncope in a tertiary hospital in São Paulo, Brazil. Those with non-interpretable ECG, known coronary artery disease, and/or other cardiomyopathies were excluded. HV interval and electrophysiological study-induced malignant ventricular arrhythmias data were analyzed. RESULTS: A total of 45 patients (60.2±11.29 years, 57.8% males) were included. The mean HV interval was 58.37 ms±10.68; 22.2% of the studied population presented an HV interval of ≥70 ms; and malignant ventricular arrhythmias were induced in 57.8% patients. The use of beta-blockers and amiodarone (p=0.002 and 0.036, respectively), NYHA functional class≥II (p=0.013), wide QRS (p=0.047), increased HV interval (p=0.02), Rassi score >6.5 (p=0.003), and reduced left ventricular ejection fraction (p=0.031) were associated with increased risk of inducible malignant ventricular arrhythmias. CONCLUSION: More than half of the patients with Chagas disease, syncope, and cardiac conduction disorder have inducible malignant ventricular arrhythmias. Prolonged HV interval was observed in only 20% of population. Wide QRS, prolonged HV, reduced ejection fraction, and higher Rassi score were associated with increased risk of malignant ventricular arrhythmias.

Intrinsecoid deflection as a risk predictor for sudden cardiac death in hypertrophic cardiomyopathy

INTRODUCTION: Sudden Cardiac Death (SCD) and Malignant Ventricular Arrhythmias (MVA) in patients with Hypertrophic Cardiomyopathy (HCM) occurs in up to 0.9%/ year. Identifying risk predictors for such an event is of paramount importance, considering the indication of Implantable Cardiodefibrillator (ICD) in patients at higher risk. The Intrinsecoid Deflection (ID) measured on the electrocardiogram showed a correlation with cardiovascular outcomes in some studies, but the literature is scarce in the analysis of this parameter in patients with HCM. OBJECTIVES and METHODS: This was a retrospective cohort study, which included patients with HCM and ICD followed in a tertiary hospital. Clinical, therapeutic and echocardiographic parameters were analyzed, in addition to the measurement of ID on the 12-lead ECG. RESULTS: 180 patients were included in the analysis, divided into 2 groups: group I (N=55) ­ in secondary prevention or who had MVA (with or without ICD therapy) and group II (N=125) ­ patients in primary prevention, who did not undergo ICD therapy. Group I showed higher values of: HCM-Risk SCD (13.5 ± 3.92 vs 6.47 ± 2.76 - p<0.001). septum thickness (25.5 ± 4.63 mm vs 22.4 ± 4.70 mm - p<0.001), EDDLV (46,8 ± 7,47 vs 43,6 ± 6,76 mm ­ p=0,008), ID in v1 (78.9 ± 16 vs 38.5 ± 11.7 - p<0.001) and ID in V5 or V6 (77.1 ± 15.4 vs 40.5 ± 10.8 - p<0.001) - Figure 1. In the multivariate analysis, the ID measurement and the occurrence of NSVT on the 24-hour Holter were the factors that best correlated with the occurrence of MVA. The analysis of the ROC curve showed a cutoff value with better sensitivity and specificity of 58 ms for the ID both in V1 and in V5 or V6 - Figure 2. CONCLUSION: In this study, the increase in ID constituted an independent predictor factor for the occurrence of MVA and, therefore, for a higher risk of SCD, in patients with HCM. The inclusion of this parameter in the risk stratification may help to better indicate an ICD to patients at higher risk.

Association between CHA2DS2-VASC score and P wave indexes and echocardiographic parameters in the absence of atrial fibrillation

INTRODUCTION: Several P wave indexes and echocardiographic data are associated with a higher risk of developing atrial fibrillation (AF) and thromboembolism; however, there are few studies in patients without AF and even less comparing these parameters with CHA2DS2-VASc score. OBJECTIVES: Primary: Evaluate the association between P wave indexes [P wave duration, dispersion and variability, maximum and minimum P wave duration, P wave voltage in lead I (PVL1), Morris index, PR interval (PRI), P/PRI ratio and P wave peak time] and CHA2DS2-VASc score in patients without AF and valve disease. Secondary: To assess the association between echocardiographic parameters [left atrium (LA) and left ventricle (LV) size, LV ejection fraction (LVEF), LV mass and LV indexed mass] and CHA2DS2-VASC score in the same population. METHODS: A cross-sectional, descriptive and analytical study in which clinical, electrocardiographic and echocardiographic data from patients without AF and valve disease were collected and analyzed. For statistical analysis, the Chi-Square Test, Mann-Whitney U-Test and Spearman Correlation (RHO) were used with the significance level of 5%. RESULTS: Mean age of the 272 consecutive patients analyzed was 62.4 ± 12.6 years and 56.6% were female. The CHA2DS2-VASc score was positively associated with PRI (RHO=0.13, p=0.032), LA (RHO=0.301, p<0.01) and VE size (RHO=0.197, p=0.01), LV mass (RHO=0.261, p<0.01) and LV indexed mass (RHO=0.340, p<0.01), while P wave amplitude (RHO=-0.141, p =0.02), PVL1 (RHO=-0.191, p=0.02) and LVEF (RHO=-0.344, p<0.01) were negatively associated with the same score (table). The presence of the Morris index was related with high CHA2DS2-VASc. The other evaluated parameters were not significantly associated with the score. CONCLUSION: This study showed significant associations between CHA2DS2-VASc score and P wave indexes and echocardiographic data. All these parameters are independent risk predictors of thromboembolism, even in the absence of AF. Therefore, these not invasive and relatively easily available tests can be useful to complement cardiovascular risk and AF development risk.