Duration of Atrial Fibrillation Episodes and Implications for the Thromboembolic Risk

Introdução: A fibrilhação auricular é uma arritmia comum e com risco tromboembólico bem documentado, estando definidas nas recomendações internacionais indicações referentes ao uso de anticoagulantes orais. Existem, contudo, lacunas de informação nomeadamente no que se refere à duração dos episódios de fibrilhação auricular e sua relação com o risco de tromboembolismo. Esta questão tem particular interesse em doentes com dispositivos electrónicos cardíacos implantados com documentação contínua da duração de episódios de taquidisritmias auriculares, que são frequentemente curtos e assintomáticos. Material e Métodos: Foi feita uma análise crítica da evidência disponível sobre a relação da duração dos episódios de FA paroxística e a ocorrência de eventos embólicos, com base numa pesquisa na base de dados bibliográfica PubMed. Resultados: Foram selecionados oito artigos com abordagens diferentes no estudo deste tema; sete com recurso a monitorização cardíaca com dispositivos electrónicos cardíacos implantados (pacemakers, cardioversores-desfibilhadores implantáveis e ressincronizadores cardíacos) e um com base em registo de Holter. Metade destas publicações, correspondendo globalmente às maiores amostragens, aborda a questão do ponto de vista do somatório diário de episódios de fibrilhação auricular (carga diária) e não da duração de cada episódio. O risco tromboembólico aumenta gradualmente com a carga arrítmica, tendo sido demonstrado um aumento significativo do risco quando esta ultrapassa os cinco minutos num dia. Discussão: A formação de um trombo intracavitário, e consequente potencial embólico, é um processo dinâmico que resulta da interacção de várias condicionantes anatómicas e funcionais. O risco individual dependerá da interacção destes factores. A associação entre fenómenos embólicos e curtos períodos de fibrilhação auricular é inequívoca, apesar do mecanismo não ser óbvio, tendo em conta a discrepância frequentemente observada entre os períodos de fibrilhação auricular e os eventos clínicos. Conclusões: O risco de eventos tromboembólicos aumenta significativamente mesmo para períodos curtos de fibrilhação auricular (≥ cinco minutos de fibrilhação auricular em um dia), apesar da relação causa-efeito não estar definida. A decisão final sobre o recurso à anticoagulação oral deve basear-se na avaliação clínica individualizada

TrueGrid: Code the table, tabulate the data

Spreadsheet systems are live programming environments. Both the data and the code are right in front you, and if you edit either of them, the effects are immediately visible. Unfortunately, spreadsheets lack mechanisms for abstraction, such as classes, function definitions etc. Programming languages excel at abstraction, but most mainstream languages or integrated development environments (IDEs) do not support the interactive, live feedback loop of spreadsheets. As a result, exploring and testing of code is cumbersome and indirect. In this paper we propose a method to bring both worlds closer together, by juxtaposing ordinary code and spreadsheet-like grids in the IDE, called TrueGrid. Using TrueGrid spreadsheet cells can be programmed with a fully featured programming language. Spreadsheet users then may enjoy benefits of source code, including added abstractions, syntax highlighting, version control, etc. On the other hand, programmers may leverage the grid for interactive exploring and testing of code. We illustrate these benefits using a prototype implementation of True- Grid that runs in the browser and uses Javascript as a programming language

Subpial Hemorrhage : A Distinctive Neonatal Stroke Pattern

Background and purpose: Subpial hemorrhage is a rare form of neonatal stroke, still poorly understood. The aim of this study was to characterize a cohort of term and preterm neonates with subpial hemorrhages and contribute to a better knowledge of this condition. Material and methods: Clinical records and magnetic resonance (MR) imaging data of all neonates with subpial hemorrhage followed at a pediatric hospital between 2010 and 2020 were retrospectively reviewed. Results: A total of 10 patients were included in the analysis, 40% of whom were term neonates. Operative vaginal delivery was registered in 30%. Temporal was the most common location of subpial hemorrhage (70%), and all patients displayed underlying brain infarction. A characteristic yin-yang pattern was present in 90% of the study cohort, and ingurgitation of medullary veins on susceptibility weighted imaging in 80%. Cerebellar microbleeds were observed in 60% of neonates, both term and preterm. When available, MR angiography and venography were unremarkable. Patients' clinical outcome was variable, with early prematurity not associated to worse outcomes. Conclusion: Subpial hemorrhage has a distinctive MR pattern, with underlying parenchymal venous infarction, and can occur in term and preterm neonates. This study results suggest an association between subpial hemorrhage and cerebellar microbleeds but further studies are required to confirm it and better understand the pathophysiology of subpial hemorrhage.info:eu-repo/semantics/publishedVersio

Remote Monitoring for Follow-Up of Patients with Implantable Cardiac Devices

O aumento significativo registado nas implantações de dispositivos cardíacos, sobretudo como consequência dos benefícios demonstrados com a utilização de cardioversoresdesfibrilhadores e sistemas de ressincronização cardíaca na redução da mortalidade, trouxe para a prática clínica hospitalar o problema da gestão de recursos para responder ao crescimento exponencial do número de doentes em consultas regulares de seguimento especializado. A era das tecnologias da comunicação permitiu desenvolver sistemas de monitorização à distância, que são hoje uma realidade em franca expansão na Europa e nos Estados Unidos, com diversas vantagens e níveis de eficácia e segurança bem documentados. A sua utilização tem permitido obter um elevado grau de satisfação para o doente e médico, reduzindo o número de visitas hospitalares e os custos inerentes ao seguimento desta população. Os resultados dos diferentes estudos têm mostrado elevada capacidade na deteção mais precoce de problemas clínicos, arrítmicos ou de descompensação da insuficiência cardíaca, e de anomalias no funcionamento do dispositivo implantado. Apesar da experiência favorável com o recurso a esta metodologia de follow-up, são necessários estudos para avaliar o seu impacto clínico a longo prazo, em comparação com as consultas convencionais, bem como a introdução e adaptação da legislação referente a este tipo de evolução tecnológica aplicada à saúde. No presente artigo, revimos os aspetos técnicos e a evidência recente da relevância clínica da monitorização à distância em portadores de dispositivos cardíacos implantados

The Atrium in Atrial Fibrillation - A Clinical Review on How to Manage Atrial Fibrotic Substrates

Atrial fibrillation (AF) is the most common sustained arrhythmia in the population and is associated with a significant clinical and economic burden. Rigorous assessment of the presence and degree of an atrial arrhythmic substrate is essential for determining treatment options, predicting long-term success after catheter ablation, and as a substrate critical in the pathophysiology of atrial thrombogenesis. Catheter ablation of AF has developed into an essential rhythm-control strategy. Nowadays is one of the most common cardiac ablation procedures performed worldwide, with its success inversely related to the extent of atrial structural disease. Although atrial substrate evaluation remains complex, several diagnostic resources allow for a more comprehensive assessment and quantification of the extent of left atrial structural remodeling and the presence of atrial fibrosis. In this review, we summarize the current knowledge on the pathophysiology, etiology, and electrophysiological aspects of atrial substrates promoting the development of AF. We also describe the risk factors for its development and how to diagnose its presence using imaging, electrocardiograms, and electroanatomic voltage mapping. Finally, we discuss recent data regarding fibrosis biomarkers that could help diagnose atrial fibrotic substrates.info:eu-repo/semantics/publishedVersio

Leadless Pacemaker Implantation Via Azygos Vein in a Patient with Absence of the Hepatic Segment of the Inferior Vena Cava

info:eu-repo/semantics/publishedVersio

Surgical Ablation of Atrial Fibrillation and Left Atrial Appendage Occlusion by a Totally Videothoracoscopic Approach - New Paradigm?

Introduction: Atrial fibrillation (AF) contributes to increased morbidity and mortality. Pharmacological and percutaneous catheter therapies are unsatisfactory, with potential serious adverse effects. Cox-Maze III/IV surgery, with higher rates of success, has not been widely adopted because of the associated complexity of the procedure. Methods: We performed a retrospective analysis of the first patients submitted to surgical ablation of AF with occlusion of the left atrial appendage with a totally videothoracoscopic (VATS) approach in our institution. We describe the surgical technique and our results, including duration of surgery, hospital stay, complications and maintenance of sinus rhythm after surgery, at 6, 12 and 18 months of follow-up. Results: We studied 15 patients (ages ranging from 39 to 75 years old; 54,5% female gender). Mean time since the diagnosis of AF was 5,75 years. All had been submitted to prior catheter ablation (mean of 2 attempts). Mean diameter and volume of the left atrium was 42 mm (M-mode) and 70 ml (43 ml/m2), respectively. Mean duration of surgery was 2 hours and 22 minutes. In one patient we had to convert the surgery to median sternotomy. Mean hospital stay was 4,8 days. Mean time of follow-up was 12 months. During follow-up, 91%, 90% and 80% of the patients were in sinus rhythm at 6, 12 and 18 months, respectively. Conclusion: This surgical approach represents a real benefit for those patients with multiple attempts of catheter ablation without success. However, a larger sample of patients with a longer period of follow-up is necessary for further conclusions.info:eu-repo/semantics/publishedVersio

Left Atrial Appendage Volume As a New Predictor of Atrial Fibrillation Recurrence After Catheter Ablation

PURPOSE: Recurrence of atrial fibrillation (AF) after catheter ablation is common, being clinically relevant to identify predictors of recurrence. The left atrial appendage (LAA) role as an AF trigger is scarcely explored. Our aim was to identify if LAA volume is an independent predictor of AF recurrence after catheter ablation. METHODS: We analysed 52 patients (aged 54 ± 10 years, 58% male) with paroxysmal and persistent AF who underwent a first AF catheter ablation and had performed contrast-enhanced cardiac computed tomography (CT) prior to the procedure. RESULTS: The mean left atrial and LAA volumes measured by cardiac CT were 98.9 ± 31.8 and 9.3 ± 3.5 mL, respectively. All patients received successful pulmonary vein isolation and were followed up for 24 months. AF recurrence occurred in 17 patients (33%). LAA volume was significantly greater in patients with AF recurrence than in those without recurrence (11.3 ± 2.9 vs. 8.2 ± 3.4 mL; p = 0.002). Multivariable analysis using Cox regression revealed that LAA volume (hazard ratio 1.32; 95% confidence interval 1.12-1.55; p = 0.001) and persistent AF (hazard ratio 4.22; 95% confidence interval 1.48-12.07; p = 0.007) were independent predictors for AF recurrence. An LAA volume greater than 8.825 mL predicted AF recurrence with 94% sensitivity and 66% specificity. The Kaplan-Meier analysis showed a lower rate free from AF recurrence in the group with an LAA volume >8.825 mL (p < 0.001). CONCLUSIONS: Larger LAA volume was associated with AF recurrence after catheter ablation in patients with paroxysmal and persistent AF.info:eu-repo/semantics/publishedVersio