EPM algorithm: A stepwise approach to accessory pathway localization in ventricular pre-excitation.

BACKGROUND: Accurate estimation of accessory pathway (AP) localization in patients with ventricular pre-excitation or Wolff-Parkinson-White (WPW) syndrome remains a diagnostic challenge. Existing algorithms have contributed significantly to this area, but alternative algorithms can offer additional perspectives and approaches to AP localization. OBJECTIVE: This study introduces and evaluates the diagnostic accuracy of the EPM algorithm in AP localization, comparing it with established algorithms Arruda and EASY. METHODS: A retrospective analysis was conducted on 138 patients from Hospital São Paulo who underwent catheter ablation. Three blinded examiners assessed the EPM algorithm's diagnostic accuracy against the Arruda and EASY algorithms. The gold standard for comparison was the radioscopic position of the AP where radiofrequency ablation led to pre-excitation disappearance on the ECG. RESULTS: EPM showed a diagnostic accuracy of 51.45%, closely aligning with Arruda (53.29%) and EASY (44.69%). Adjacency accuracy for EPM was 70.67%, with Arruda at 66.18% and EASY at 72.22%. Sensitivity for EPM in distinguishing left vs. right APs was 95.73%, with a specificity of 74.33%. For identifying septal vs. lateral right APs, EPM sensitivity was 82.79% with a specificity of 46.15%. These measures were comparable to those of Arruda and EASY. Inter-observer variability was excellent for EPM, with Kappa statistics over 0.9. CONCLUSION: The EPM algorithm emerges as a reliable tool for AP localization, offering a systematic approach beneficial for therapeutic decision-making in electrophysiology. Its comparable diagnostic accuracy and excellent inter-observer variability underscore its potential clinical applicability. Future research may further validate its efficacy in a broader clinical setting.

EPM algorithm: a stepwise approach to accessory pathway localization in ventricular pre-excitation

BACKGROUND: Accurate estimation of accessory pathway (AP) localization in patients with ventricular pre-excitation or Wolff-Parkinson-White (WPW) syndrome remains a diagnostic challenge. Existing algorithms have contributed significantly to this area, but alternative algorithms can offer additional perspectives and approaches to AP localization. OBJECTIVE: This study introduces and evaluates the diagnostic accuracy of the EPM algorithm in AP localization, comparing it with established algorithms Arruda and EASY. METHODS: A retrospective analysis was conducted on 138 patients from Hospital São Paulo who underwent catheter ablation. Three blinded examiners assessed the EPM algorithm's diagnostic accuracy against the Arruda and EASY algorithms. The gold standard for comparison was the radioscopic position of the AP where radiofrequency ablation led to pre-excitation disappearance on the ECG. RESULTS: EPM showed a diagnostic accuracy of 51.45%, closely aligning with Arruda (53.29%) and EASY (44.69%). Adjacency accuracy for EPM was 70.67%, with Arruda at 66.18% and EASY at 72.22%. Sensitivity for EPM in distinguishing left vs. right APs was 95.73%, with a specificity of 74.33%. For identifying septal vs. lateral right APs, EPM sensitivity was 82.79% with a specificity of 46.15%. These measures were comparable to those of Arruda and EASY. Inter-observer variability was excellent for EPM, with Kappa statistics over 0.9. CONCLUSION: The EPM algorithm emerges as a reliable tool for AP localization, offering a systematic approach beneficial for therapeutic decision-making in electrophysiology. Its comparable diagnostic accuracy and excellent inter-observer variability underscore its potential clinical applicability. Future research may further validate its efficacy in a broader clinical setting.

Guideline of the Brazilian Society of Cardiology on Diagnosis and Treatment of Patients with Chagas Disease Cardiomyopathy / Diretriz da Sociedade Brasileira de Cardiologia sobre Diagnóstico e Tratamento de Pacientes com Cardiomiopatia da Doença de Chagas

This guideline aimed to update the concepts and formulate the standards of conduct and scientific evidence that support them, regarding the diagnosis and treatment of the Cardiomyopathy of Chagas disease, with special emphasis on the rationality base that supported it.  Chagas disease in the 21st century maintains an epidemiological pattern of endemicity in 21 Latin American countries. Researchers and managers from endemic and non-endemic countries point to the need to adopt comprehensive public health policies to effectively control the interhuman transmission of T. cruzi infection, and to obtain an optimized level of care for already infected individuals, focusing on diagnostic and therapeutic opportunistic opportunities.   Pathogenic and pathophysiological mechanisms of the Cardiomyopathy of Chagas disease were revisited after in-depth updating and the notion that necrosis and fibrosis are stimulated by tissue parasitic persistence and adverse immune reaction, as fundamental mechanisms, assisted by autonomic and microvascular disorders, was well established. Some of them have recently formed potential targets of therapies.  The natural history of the acute and chronic phases was reviewed, with enhancement for oral transmission, indeterminate form and chronic syndromes. Recent meta-analyses of observational studies have estimated the risk of evolution from acute and indeterminate forms and mortality after chronic cardiomyopathy. Therapeutic approaches applicable to individuals with Indeterminate form of Chagas disease were specifically addressed. All methods to detect structural and/or functional alterations with various cardiac imaging techniques were also reviewed, with recommendations for use in various clinical scenarios. Mortality risk stratification based on the Rassi score, with recent studies of its application, was complemented by methods that detect myocardial fibrosis.  The current methodology for etiological diagnosis and the consequent implications of trypanonomic treatment deserved a comprehensive and in-depth approach. Also the treatment of patients at risk or with heart failure, arrhythmias and thromboembolic events, based on pharmacological and complementary resources, received special attention. Additional chapters supported the conducts applicable to several special contexts, including t. cruzi/HIV co-infection, risk during surgeries, in pregnant women, in the reactivation of infection after heart transplantation, and others.     Finally, two chapters of great social significance, addressing the structuring of specialized services to care for individuals with the Cardiomyopathy of Chagas disease, and reviewing the concepts of severe heart disease and its medical-labor implications completed this guideline.

Esta diretriz teve como objetivo principal atualizar os conceitos e formular as normas de conduta e evidências científicas que as suportam, quanto ao diagnóstico e tratamento da CDC, com especial ênfase na base de racionalidade que a embasou. A DC no século XXI mantém padrão epidemiológico de endemicidade em 21 países da América Latina. Investigadores e gestores de países endêmicos e não endêmicos indigitam a necessidade de se adotarem políticas abrangentes, de saúde pública, para controle eficaz da transmissão inter-humanos da infecção pelo T. cruzi, e obter-se nível otimizado de atendimento aos indivíduos já infectados, com foco em oportunização diagnóstica e terapêutica. Mecanismos patogênicos e fisiopatológicos da CDC foram revisitados após atualização aprofundada e ficou bem consolidada a noção de que necrose e fibrose sejam estimuladas pela persistência parasitária tissular e reação imune adversa, como mecanismos fundamentais, coadjuvados por distúrbios autonômicos e microvasculares. Alguns deles recentemente constituíram alvos potenciais de terapêuticas. A história natural das fases aguda e crônica foi revista, com realce para a transmissão oral, a forma indeterminada e as síndromes crônicas. Metanálises recentes de estudos observacionais estimaram o risco de evolução a partir das formas aguda e indeterminada e de mortalidade após instalação da cardiomiopatia crônica. Condutas terapêuticas aplicáveis aos indivíduos com a FIDC foram abordadas especificamente. Todos os métodos para detectar alterações estruturais e/ou funcionais com variadas técnicas de imageamento cardíaco também foram revisados, com recomendações de uso nos vários cenários clínicos. Estratificação de risco de mortalidade fundamentada no escore de Rassi, com estudos recentes de sua aplicação, foi complementada por métodos que detectam fibrose miocárdica. A metodologia atual para diagnóstico etiológico e as consequentes implicações do tratamento tripanossomicida mereceram enfoque abrangente e aprofundado. Também o tratamento de pacientes em risco ou com insuficiência cardíaca, arritmias e eventos tromboembólicos, baseado em recursos farmacológicos e complementares, recebeu especial atenção. Capítulos suplementares subsidiaram as condutas aplicáveis a diversos contextos especiais, entre eles o da co-infecção por T. cruzi/HIV, risco durante cirurgias, em grávidas, na reativação da infecção após transplante cardíacos, e outros.    Por fim, dois capítulos de grande significado social, abordando a estruturação de serviços especializados para atendimento aos indivíduos com a CDC, e revisando os conceitos de cardiopatia grave e suas implicações médico-trabalhistas completaram esta diretriz. 

Epicardial mapping complicated by multi-vessel coronary spasm and electrical storm.

The case report describes a severe multi-vessel coronary spasm complicating the epicardial mapping in a patient with chronic Chagas cardiomyopathy.

Underuse of Catheter Ablation as First-Line Therapy for Supraventricular Tachycardia.

Background Catheter ablation (CA) is a safe, effective, cost-effective technique and may be considered a first-line strategy for the treatment of symptomatic supraventricular tachycardias (SVT). Despite the high prospect of cure and the recommendations of international guidelines in considering CA as a first-line treatment strategy, the average time between diagnosis and the procedure may be long. The present study aims to evaluate predictors related to non-referral for CA as first-line treatment in patients with SVT. Methods and Results The model was derived from a retrospective cohort of patients with SVT or ventricular pre-excitation referred for CA in a tertiary center. Clinical and demographical features were used as independent variables and non-referral for CA as first-line treatment the dependent variable in a stepwise logistic regression analysis. Among 20 clinical-demographic variables from 350 patients, 10 were included in initial logistic regression analysis: age, women, presence of pre-excitation on ECG, palpitation, dyspnea and chest discomfort, number of antiarrhythmic drugs before ablation, number of concomitant symptoms, symptoms' duration and evaluations in the emergency room due to SVT. After multivariable adjusted analysis, age (odds ratio [OR], 1.2; 95% CI 1.01-1.32; P=0.04), chest discomfort during supraventricular tachycardia (OR, 2.7; CI 1.6-4.7; P<0.001) and number of antiarrhythmic drugs before ablation (OR, 1.8; CI 1.4-2.3; P<0.001) showed a positive independent association for non-referral for CA as SVT first-line treatment. Conclusions The independent predictors of non-referral for CA as first-line treatment in our logistic regression analysis indicate the existence of biases in the decision-making process in the referral process of patients who would benefit the most from catheter ablation. They very likely suggest a skewed medical decision-making process leading to catheter ablation underuse.

Pacemaker lead-related macroreentrant atrial tachycardia.

Macroreentrant atrial circuits are frequently associated with scarring. Previous reports have shown the possible development of scar tissue that is adjacent to pacemaker (PM) leads. However, reports of PM lead-related reentrant tachycardia are scarce. We report the case of a 63-year-old woman who presented with macroreentrant atrial tachycardia (MAT), related to the atrial trajectory of an old single-lead ventricular PM, that was successfully treated with radiofrequency ablation after a conventional electrophysiological study ruled out isthmus-dependent atrial flutter and provided sufficient data to confirm this diagnosis. This report presents a case of MAT originating around the trajectory of a PM lead, probably because of scar tissue that developed adjacent to the lead. Experimental studies have already shown that interstitial atrial fibrosis may develop adjacent to a ventricular single-lead. This finding suggests that MAT develops in patients with this specific condition. Recognizing this condition is important for managing these arrhythmias and performing safe ablation with the preservation of PM lead integrity.

Long-term clinical outcomes of patients with nonsignificant transplanted renal artery stenosis.

BACKGROUND: Transplant renal artery stenosis (TRAS) is the main vascular complication of kidney transplantation. For research and treatment purposes, several authors consider critical renal artery stenosis to be greater than 50%, and percutaneous intervention is indicated in this scenario. However, there are no reports in the current literature on the evolution of patients with less than 50% stenosis. METHOD: This retrospective study included data from all patients who underwent kidney transplantation and were suspected of having TRAS after transplantation with stenosis under 50% independent of age and were referred for angiography at a single centre between January 2007 and December 2014. RESULTS: During this period, 6,829 kidney transplants were performed at Hospital do Rim, 313 of whom had a clinical suspicion of TRAS, and 54 of whom presented no significant stenosis. The average age was 35.93 years old, the predominant sex was male, and most individuals (94.4%) underwent dialysis before transplantation. In most cases in this group, transplants occurred from a deceased donor (66.7%). The time between transplantation and angiography was less than one year in 79.6% of patients, and all presented nonsignificant TRAS. Creatinine levels, systolic blood pressure, diastolic blood pressure and glomerular filtration rate improved over the long term. The outcomes found were death and allograft loss. CONCLUSION: Age, sex and ethnic group of patients were factors that did not interfere with the frequency of renal artery stenosis. The outcomes showed that in the long term, most patients evolve well and have improved quality of life and kidney function, although there are cases of death and kidney loss.

Epicardial and Endocardial Ablation Based on Channel Mapping in Patients With Ventricular Tachycardia and Chronic Chagasic Cardiomyopathy: Importance of Late Potential Mapping During Sinus Rhythm to Recognize the Critical Substrate.

Background Ventricular tachycardia (VT) in patients with chronic chagasic cardiomyopathy (CCC) is associated with considerable morbidity and mortality. Catheter ablation of VT in patients with CCC is very complex and challenging. The main goal of this work was to assess the efficacy of VT catheter ablation guided by late potentials (LPs) in patients with CCC. Methods and Results Seventeen consecutive patients with refractory VT and CCC were prospectively included in the study. Combined endo-epicardial voltage and late activation mapping were obtained during baseline rhythm to define scarred and LP areas, respectively. The end point of the ablation procedure was the elimination of all identified LPs. Epicardial and endocardial dense scars (<0.5 mV) were detected in 17/17 and 15/17 patients, respectively. LPs were detected in the epicardial scars of 16/17 patients and in the endocardial scars of 14/15 patients. A total of 63 VTs were induced in 17 patients; 22/63 (33%) were stable and entrained, presenting LPs recorded in the isthmus sites. The end point of ablation was achieved in 15 of 17 patients. Ablation was not completed in 2 patients because of cardiac tamponade or vicinity of the phrenic nerve and circumflex artery. Three patients (2 with unsuccessful ablation) had VT recurrence during follow-up (39 months). Conclusions Endo-epicardial LP mapping allows us to identify the putative isthmuses of different VTs and effectively perform catheter ablation in patients with CCC and drug-refractory VTs.

MANEJO DO HIPERTENSO COM FIBRILAÇÃO ATRIAL. O QUE MUDOU NA PRÁTICA MÉDICA? / HYPERTENSION AND ATRIAL FIBRILLATION: RECENT ADVANCES

A fibrilação atrial (FA) é a arritmia cardíaca sustentada mais comum na prática clínica. Estima se que 1 a 2% da população mundial seja acometida dessa arritmia e ainda se reconhece que este número está subestimado, dado que até um terço dos pacientes com FA são assintomáticos. Além dos fatores de risco clássicos como diabetes, doença valvar, infarto do miocárdio e insuficiência cardíaca, insuficiência renal crônica, obesidade e apneia obstrutiva do sono, a hipertensão tem um papel muito impactante no surgimento da FA pela sua alta prevalência, com isso sendo o fator de risco mais comum para o desenvolvimento de FA. O manejo adequado da HA é importante para prevenção da FA, controle do ritmo, insuficiência cardíaca e prevenção do acidente vascular cerebral (AVC). O tratamento deve ser integrado por equipe multidisciplinar, individualizando caso a caso, estando sujeito a mudanças ao longo do tempo, com o desenvolvimento de novos fatores de risco, sintomas, progressão da doença e com advento de novos tratamentos. Algumas drogas, tais como os BRAs e iECA parecem apresentar mecanismos específicos de atuação na redução do risco de arritmias. A ablação por cateter pode ser a estratégia mais eficaz para manutenção do ritmo sinusal, em paciente sintomáticos. O objetivo dessa revisão é resumir os dados atuais referente ao manejo do paciente hipertenso com fibrilação atrial.

Worldwide, AF is the most common sustained cardiac arrhythmia in adults. The currently estimated prevalence and incidence in the world are rising, owing to extended longevity and increased survival with chronic diseases. This multifactorial arrhythmia is intertwined with common concomitant cardiovascular diseases, which share classical cardiovascular risk factors, including hypertension, diabetes mellitus, heart failure (HF), coronary artery disease (CAD), chronic kidney disease (CKD), obesity, and obstructive sleep apnoea (OSA). The most common risk factor for AF in the general population is hypertension, and in these patients, left ventricular hypertrophy followed by left atrial enlargement creates the anatomical substrate for AF. Adequate management of hypertension is important for AF prevention, rhythm control, heart failure, and stroke prevention. Integrated management of AF patients requires a coordinated and agreed patient-individualized care pathway to deliver optimized treatment by an interdisciplinary team. The effect of some anti hypertensives, such as RAAS Inhibitors seems to be superior to other antihypertensive treatment to prevent AF recurrences in hypertensive patients with paroxysmal AF beyond the BP reduction. Guidelines suggest a more prominent role for radiofrequency ablation in the treatment of atrial fibrillation (AF), including its use as first-line therapy in recurrent symptomatic paroxysmal or persistent AF in whom a rhythm control strategy is chosen. The objective of this review is to summarize current data on the hypertension in relation to AF, their management, and ongoing research in the field.

Examining therapeutic equivalence between branded and generic warfarin in Brazil: The WARFA crossover randomized controlled trial.

OBJECTIVES: To determine whether the generic and branded warfarins used as anticoagulants in Brazil are therapeutic equivalents based on their international normalized ratio (INR) results. METHODS: This crossover randomized controlled trial had four periods. We used the branded Marevan and two generic versions of warfarin sodium tablets, manufactured by União Química and Teuto laboratories, all purchased from retail drugstores. Eligible participants were outpatients from an anticoagulation clinic at a university hospital in São Paulo, Brazil. They had atrial fibrillation or flutter and had been using warfarin for at least 2 months with an INR therapeutic range of 2.0-3.0. Randomization was by numbered, opaque, sealed envelopes. Healthcare personnel and outcome assessors were blinded to treatments, but patients were not. The primary outcome was the variability in the INR (ΔINR) and secondary outcomes included mean INR. We accepted formulations as equivalent if the 95% confidence interval (CI) of the comparison of ΔINR between branded and generic formulations was within the limit of ±0.49. RESULTS: One hundred patients were recruited and randomized to six sequences of treatment (four sequences with n = 17 and two sequences with n = 16). União Química generic warfarin had equivalent variability in the INR to Marevan (ΔINR +0.09 [95% CI -0.29 to +0.46], n = 84). Comparison between Teuto generic warfarin and Marevan was inconclusive (ΔINR +0.29 [95% CI -0.09 to +0.68], n = 84). CONCLUSIONS: Marevan and União Química warfarin had equivalent therapeutic effectiveness and both could be confidently used for anticoagulation. The comparison between Marevan and TW was inconclusive and does not warrant a statement of equivalence. Our methods are especially important for comparing generic and branded drugs that raise concerns and may be subject of future investigations by regulatory agents. TRIAL REGISTRATION: ClinicalTrials.gov NCT02017197.

Impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction patients.

PURPOSE: The negative association between obstructive sleep apnea (OSA) and adverse cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) is well documented. However, little is known about the influence of OSA on fibrinolytic therapy. The aim of this study was to evaluate the impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction (STEMI) patients. METHODS: We enrolled consecutive STEMI patients without previous vascular disease, heart failure, or OSA diagnosis. All patients underwent either a pharmacoinvasive therapy or primary PCI. Syntax score (SS) was calculated for all patients, and a full bedside polysomnography was performed in the first 72 h of admission. In-hospital events and 30 days readmissions were analyzed. RESULTS: The sample included 116 patients, 87 men. Patients with severe OSA were older (p = 0.01), had higher neck and abdominal circumferences (p < 0.01), and had higher BMI (p < 0.01). They also had lower reperfusion rates post-fibrinolysis (20 vs. 65%; p = 0.001), higher SS (20.2 ± 11.2 vs. 14.6 ± 10.6; p = 0.03), lower left ventricle ejection fraction (45 ± 8 vs. 51 ± 10%; p = 0.02), and a higher incidence of atrial arrhythmias (4 vs. 21%; p = 0.02). STEMI patients with severe OSA presented with threefold increase in the risk for at least one adverse outcome. Regression analysis showed that both severe OSA and hypertension were independent predictors of higher SS. CONCLUSION: Severe OSA was associated with a poor outcome after pharmacoinvasive treatment in STEMI patients.

Programa de exercício monitorado e integrado: um novo protocolo não farmacológico para tratamento da síncope vasovagal / Monitored and integrated exercise program: a new non-pharmacological protocol for treatment of syncope vasovagal

INTRODUÇÃO: Vários tratamentos foram propostos para a abordagem terapêutica da síncope vasovagal (SVV), entretanto, as evidências científicas no longo prazo não foram satisfatórias. Os autores testaram a hipótese que um amplo programa não farmacológico, incluindo diversas modalidades de exercícios, suporte e mudança de qualidade de vida é efetivo no tratamento da SVV. O objetivo desse estudo foi avaliar o impacto de um programa de exercício monitorado e integrado (PEMI) na taxa de recorrência e qualidade de vida de pacientes portadores de SVV. MÉTODOS: Foram incluídos os pacientes com diagnóstico de SVV de ambos os sexos, de 18 a 70 anos, sem evidência de doença cardíaca estrutural com pelo menos 3 episódios de síncope nos últimos 3 meses. O IMEP inclui exercícios aeróbicos, propriocepção, isométricos, treinamento postural passivo, além de modificação de estilo de vida, educação sobre a condição de saúde e suporte. O programa é constituído de 32 sessões aplicadas ao longo de 18 meses. A taxa de recorrência e a qualidade de vida foram avaliadas no início e final do estudo. Análise estatística foi realizada com o SPSS 19.0. RESULTADOS: Cem pacientes foram avaliados e 20 foram elegíveis a participar no grupo PEMI. O grupo controle consistiu de 20 pacientes pareados por sexo e idade submetidos ao tratamento convencional segundo as diretrizes atuais. O teste de inclinação foi positivo em 90% dos pacientes do grupo PEMI ao passo que todos os pacientes do grupo convencional tiveram o teste positivo. O número de síncopes no último mês diminuiu significativamente no grupo PEMI quando comparado com o grupo controle (pré-protocolo: 1,25±0,21, pós protocolo 0,25±0,13 versus pré-protocolo: 0,9±0,21, pós-protocolo: 1,2±0,13, respectivamente, p>0,001). O mesmo ocorreu na avaliação do número de síncopes e pré-síncopes no último trimestre. O impacto do PEMI na qualidade de vida encontra-se na figura 1. CONCLUSÃO: O PEMI demonstrou reduzir a recorrência de síncope e melhorar a qualidade de vida de pacientes portadores de SVV na amostra estudada. (AU)

Ventricular arrhythmias in the Chagas disease are not random phenomena: Long-term monitoring in Chagas arrhythmias.

BACKGROUND: Variability of ventricular arrhythmias among days in patients with Chagas disease is not detected by 24 hours of Holter monitoring. OBJECTIVE: To analyze whether ventricular arrhythmias are a random phenomenon or have a reproducible behavior in patients with Chagas cardiomyopathy. METHOD: Holter monitoring was recorded in 16 subjects with a mean age of 52 ± 8 years. They were clinically stable and had ventricular couplets, isolated premature ventricular contractions (PVCs), and nonsustained ventricular tachycardia (NSVT). The recordings occurred for 7 days. Hurst exponent (HE) evaluated randomness and predictability index (PI) and repeated analysis of variance (ANOVA) assessed reproducibility. RESULTS: The HE was significantly greater than 0.5 in all 16 patients, which confirms the nonrandomness of arrhythmias in this Chagas sample. The PI for ventricular couplets and isolated PVCs was, on average, 38% and 54%, respectively. ANOVA with repeated measurement showed significant differences in the daily frequency of ventricular couplets (n = 15, P ≤ .05), isolated PVC (n = 12, P ≤ .05), and NSVT (n = 7, P ≤ .05). CONCLUSION: Ventricular arrhythmias in Chagas cardiomyopathy are not random. Dissimilarities in arrhythmias frequency make unlikely that 24 hours of Holter recording can capture this variability.

Catheter entrapment in Chiari network: Extraction with radiofrequency.

We report a challenging case of a duodecapolar mapping catheter entrapment in Chiari network and its release by radiofrequency energy application with an ablation catheter.

Clinical value of myocardial performance index in patients with isolated diastolic dysfunction.

AIMS: The Doppler-derived myocardial performance index (MPI) has been considered as a diagnostic and prognostic Doppler marker for many different clinical conditions. The purpose of this study was to determine the diagnostic accuracy of traditional Pulsed-wave Doppler (PWD-MPI) and Pulsed-wave tissue Doppler imaging (TDI-MPI) and the degree of agreement between these methods in patients with grade-I diastolic dysfunction (DDI) and a normal ejection fraction. METHODS: Forty-seven consecutive ambulatory patients with DDI were compared to 51 healthy subjects with normal echocardiograms. All subjects underwent measurement of time intervals and MPI with PWD and pulsed TDI. RESULTS: TDI-MPI and PWD-MPI were significantly higher in patients with DDI than in control subjects: 0.49 ± 0.14 vs. 0.40 ± 0.09 (P < 0.001) and 0.45 ± 0.11 vs. 0.37 ± 0.08 (P < 0.001), respectively. Cutoff values of TDI-MPI > 0.42 and PWD-MPI > 0.40 identified DDI subjects, with sensitivities of 74 and 64%; specificities of 61 and 69%; positive likelihood ratios of 1.9 and 2.0; and negative likelihood ratios of 0.42 and 0.53, respectively; no significant difference was noted between the areas under the ROC curves of TDI-MPI and PWD-MPI (P = 0.77). Bland-Altman plots showed wide limits of agreement between these indices: - 0.17 to 0.23 in healthy subjects and - 0.24 to 0.32 in DDI patients. CONCLUSION: PWD-MPI and TDI-MPI showed poor clinical agreement and were not reliable parameters for the assessment of left ventricular diastolic function.

Prevalence of atrial fibrillation and stroke risk assessment based on telemedicine screening tools in a primary healthcare setting.

BACKGROUND: Worldwide atrial fibrillation (AF) prevalence varies between 0.1% and 4.0%, and has been increasing. Little is known about the prevalence of AF in Brazil. Our objective was to estimate the prevalence of AF in several regions of Brazil using recordings of long-distance electrocardiogram (ECG) transmission. METHODS: Patients from 125 outpatient general practitioner units covered by the telemedicine service of the Federal University of São Paulo were included. Only one ECG was considered per patient. A scripted telephone interview was also performed. We analyzed the data to project the prevalence of AF in the Brazilian population and estimate it for the year 2025. The overall AF prevalence was calculated based on ECGs from primary care units where patients went for routine visits. RESULTS: Based on 676,621 ECG exams from January 2009 through April 2016, the mean age (±SD) of patients was 51.38 (±19.05) years, with 57.5% being female. The 7-year period prevalence of AF was 2.2% (n = 14,968). The prevalence of AF countrywide was projected to be 1.5% in 2016 and 1.7% in 2025. In the subset of patients with AF who were interviewed (n = 301), 91 (30.2%) were not receiving any type of treatment for rate or rhythm control. Among patients interviewed, 189 (62.8%) were at high risk for stroke; only 28 (14.8%) were regular oral anticoagulant users. CONCLUSIONS: Our study highlights the importance of screening for AF in the primary care setting in Brazil and identifies important gaps in the treatment of AF in this population.

Radiofrequency ablation of a middle cardiac vein inserted accessory pathway resulting in posterolateral coronary artery occlusion: A case report.

INTRODUCTION: Posteroseptal accessory pathways account for 34.5% of the total. Of these, 36% are located within the coronary sinus (CS). Its ablation requires technical alternatives to avoid damage to surrounding tissues, especially branches of the right coronary artery. CASE REPORT: A 22-year-old man was referred for re-do ablation of an accessory left septal-septal (PSE) pathway. Inside the CS, a precocity of 25 ms was found in the region of the median cardiac vein (VCM) (Fig. 2, panel A). Radiofrequency (RF) was administered with a non-irrigated bidirectional catheter within this vessel with resolution of the pre-excitation after 5 seconds. Immediately after, the patient presented chest pain and revealed a ST segment elevation of 1 mm in the inferior leads of ECG. Coronary angiography showed occlusion of the middle third of the posterior ventricular branch of the right coronary artery, with no signs of thrombus or dissection. Arterial angioplasty was performed with a bare metal stent, followed by TIMI III distal flow. Retrograde aortic mapping was performed and a precocity of 20 ms was found in the PSE region. The RF was applied followed by loss of pre-excitation after 1.5 seconds of application. CONCLUSION: This case demonstrates the risks involving delivering radiofrequency within the coronary sinus. We discuss some strategy that could help electrophysiologists in similar cases.

Atrial fibrillation promotion in a rat model of heart failure induced by left ventricle radiofrequency ablation.

BACKGROUND: Atrial fibrillation (AF) frequently coexists with congestive heart failure (CHF). The increased susceptibility to AF in CHF has been attributed to a variety of structural and electrophysiological changes in the atria, particularly dilation and interstitial fibrosis. We evaluated atrial remodeling and AF vulnerability in a rat model of CHF induced by left ventricle (LV) radiofrequency (RF) ablation. METHODS: Wistar rats were divided into 3 groups: RF-induced CHF (Ab, n = 36), CHF animals treated with spironolactone (AbSpi, n = 20) and sham controls (Sham, n = 29). After 12 weeks, animals underwent echocardiographic and electrophysiological evaluation and were sacrificed for histological (atrial fibrosis) and Western blotting (TGF-ß1, collagen I/III, connexin 43 and CaV1.2) analysis. RESULTS: Mild LV dysfunction and marked atrial enlargement were noted in both ablated groups. AF inducibility (episodes ≥2 s) increased in the Ab group compared to sham animals (31/36, 86%; vs. 15/29, 52%; p = 0.005), but did not differ from the AbSpi group (16/20, 80%; p = NS). Sustained AF (>30 s) was also more frequent in the Ab group compared to shams (56% vs. 28%; p = 0.04). Spironolactone reduced atrial fibrosis (p < 0.01) as well as TGF-ß1 (p < 0.01) and collagen I/III (p < 0.01) expression but did not affect connexin 43 and CaV1.2 expression. CONCLUSIONS: Rats with RF-induced CHF exhibit pronounced atrial structural remodeling and enhanced AF vulnerability. This model may be useful for studying AF substrate in CHF.

Arritmias cardíacas na sala de emergência e UTI. Anticoagulação do paciente com FA aguda submetido a cardioversão: já podemos contar com os novos anticoagulantes orais? / Cardiac arrhythmias in the emergency room and ICU. Anticoagulation of the patient with acute af undergoing cardioversion: can we rely on the new oral antioagulants?

A fibrilação atrial (FA) é a arritmia cardíaca mais comum na população com uma prevalência de 1-2%, além disso, está associada a um risco, aproximadamente cinco vezes maior de acidente vascular cerebral do que na população em geral. A anticoagulação é a melhor maneira de prevenir os eventos tromboembólicos. A varfarina é utilizada há décadas como uma droga segura e eficaz, desde que rigorosamente controlada. Nos últimos anos, foram desenvolvidas novas classes de anticoagulantes orais: inibidores diretos da trombina e inibidores do fator Xa, conhecidos como anticoagulantes orais de ação direta (DOACs). Tanto a cardioversão elétrica quanto a cardioversão farmacológica estão associadas a um maior risco de eventos tromboembólicos durante o primeiro mês após o procedimento (5-7%). No entanto, com a utilização de nticoagulantes essa taxa é inferior a 1%. No presente artigo, faremos uma revisão das principais evidências científicas relacionadas ao uso da dabigatrana, rivaroxabana, apixabana e edoxabana durante a cardioversão e uma abordagem prática com o manejo antitrombótico em diferentes cenários clínicos (cardioversão em pacientes com uso prévio de DOACs, cardioversão em pacientes com FA com duração maior ou menor que 48 horas sem anticoagulação)

Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice with a prevalence of 1-2%, and is associated with an almost 5-fold increase in the risk of stroke compared to the general population. Anticoagulation is the best way to prevent thromboembolic events. Warfarin has been used for decades as a safe and effective drug, provided it is strictly controlled. In recent years, new classes of oral anticoagulants have been developed: direct thrombin inhibitors and factor Xa inhibitors, known as direct oral anticoagulants (DOACs). Both electrical and pharmacological cardioversion are associated with an increased risk of thromboembolic events during the first month after the procedure (5-7%). However, with the use of anticoagulants, this rate is less than 1%. In this article, we will review the main scientific evidence related to the use of dabigatran, rivaroxaban, apixaban and edoxaban during cardioversion and a practical approach with antithrombotic management in different clinical scenarios (cardioversion of patients in previous use of DOACs, cardioversion of patients not using oral anticoagulants with episodes of AF longer or shorter than 48 h)