Search results for "Fibrillation"
showing 10 items of 509 documents
2D Isochronal Correlation Method to Detect Pacing Capture during Ventricular Fibrillation
2009
During ventricular fibrillation (VF), a portion of myocardial tissue can be captured by pacing at a rate near the fibrillation rate. Interruption of ventricular fibrillation can be favored by achieving stable myocardial capture, lowering the energy required for electrical cardioversion. Existence of myocardial capture during electrical stimulation is determined by visual inspection of electrograms (EGM) by an experienced observer. The objective of this work is the development of a semi-automatic method for the detection of myocardial capture based on the 2D correlation of isochronal maps. In 4 isolated rabbit hearts VF was induced by ventricular pacing with an increasing rate. An array of 1…
Analysis of the Modifications in the Spectral and Morphologic Regularity during Ventricular Fibrillation Produced by Physical Exercise and the Use of…
2015
Chronic physical exercise modifies cardiac activity improving response to malignant arrhythmia and, specifically, ventricular fibrillation (VF). Drug administration as glibenclamide, responsible for K + ATP channel blocking, is also generating a positive response against fibrillation.
Local electrical characterisation of human atrial fibrillation
2002
The rate of success of radio-frequency catheter ablation in the treatment of atrial fibrillation may be significantly improved by evaluating the local electrical properties of the atrial tissue. The aim of this study is the development of an automatic procedure for the characterisation of the local electrical activity during atrial fibrillation and the comparison of its performance with the manual analysis. The adopted procedures were the semi-automatic measurement of the local fibrillation intervals (A-A intervals) and the manual electrogram classification following the criteria suggested by Wells (1978) or Konings (1997). Two methods have been used: Principal Component Analysis and Cluste…
Ventricular Fibrillation and Tachycardia Detection Using Features Derived from Topological Data Analysis
2022
A rapid and accurate detection of ventricular arrhythmias is essential to take appropriate therapeutic actions when cardiac arrhythmias occur. Furthermore, the accurate discrimination between arrhythmias is also important, provided that the required shocking therapy would not be the same. In this work, the main novelty is the use of the mathematical method known as Topological Data Analysis (TDA) to generate new types of features which can contribute to the improvement of the detection and classification performance of cardiac arrhythmias such as Ventricular Fibrillation (VF) and Ventricular Tachycardia (VT). The electrocardiographic (ECG) signals used for this evaluation were obtained from…
A Novel Approach to Propagation Pattern Analysis in Intracardiac Atrial Fibrillation Signals
2010
The purpose of this study is to investigate propagation patterns in intracardiac signals recorded during atrial fibrillation (AF) using an approach based on partial directed coherence (PDC), which evaluates directional coupling between multiple signals in the frequency domain. The PDC is evaluated at the dominant frequency of AF signals and tested for significance using a surrogate data procedure specifically designed to assess causality. For significantly coupled sites, the approach allows also to estimate the delay in propagation. The methods potential is illustrated with two simulation scenarios based on a detailed ionic model of the human atrial myocyte as well as with real data recordi…
Chronic Apical and Nonapical Right Ventricular Pacing in Patients with High-Grade Atrioventricular Block: Results of the Right Pace Study
2018
Objective. The aim of the study was to compare the two approaches to chronic right ventricular pacing currently adopted in clinical practice: right ventricular apical (RVA) and non-RVA pacing. Background. Chronic RVA pacing is associated with an increased risk of atrial fibrillation, morbidity, and even mortality. Non-RVA pacing may yield more physiologic ventricular activation and provide potential long-term benefits and has recently been adopted as standard procedure at many implanting centers. Methods. The Right Pace study was a multicenter, prospective, single-blind, nonrandomized trial involving 437 patients indicated for dual-chamber pacemaker implantation with a high percentage of RV…
Genome-wide association meta-analysis of PR interval identifies 47 novel loci associated with atrial and atrioventricular electrical activity
2018
ABSTRACTElectrocardiographic PR interval measures atrial and atrioventricular depolarization and conduction, and abnormal PR interval is a risk factor for atrial fibrillation and heart block. We performed a genome-wide association study in over 92,000 individuals of European descent and identified 44 loci associated with PR interval (34 novel). Examination of the 44 loci revealed known and novel biological processes involved in cardiac atrial electrical activity, and genes in these loci were highly over-represented in several cardiac disease processes. Nearly half of the 61 independent index variants in the 44 loci were associated with atrial or blood transcript expression levels, or were i…
Impacto pronóstico a largo plazo de la anticoagulación en pacientes en hemodiálisis con fibrilación auricular
2018
Resumen: Introducción y objetivos: La evidencia de la eficacia y seguridad de la anticoagulación oral con dicumarínicos en pacientes en hemodiálisis con fibrilación auricular (FA) es controvertida. El objetivo de nuestro estudio es evaluar las implicaciones a nivel pronóstico a largo plazo de la anticoagulación con dicumarínicos en una cohorte de pacientes con FA no valvular en programa de hemodiálisis debido a insuficiencia renal terminal. Métodos: Estudio observacional retrospectivo con inclusión consecutiva de 74 pacientes en hemodiálisis con FA. El periodo de inclusión fue de enero de 2005 a octubre de 2016. Las variables principales fueron mortalidad por todas las causas, reingresos no…
Dépistage séquentiel de la FA silencieuse post-AVC (Stepwise screening for silent Atrial Fibrillation After Stroke : SAFAS study)
2019
Introduction Un tiers des AVC cryptogeniques seraient secondaires a une fibrillation atriale (FA) silencieuse non-detectee par les methodes usuelles. Trois versants seraient impliques dans le developpement d’une arythmie (le substrat atrial, le modulateur, le declencheur). Objectifs L’objectif etait d’identifier les deregulations physiopathologiques conduisant au developpement de la FA. Patients et methodes Etaient inclus les patients hospitalises pour un AVC ischemique au sein de l’USINV du CHU de Dijon, d’etiologie indeterminee a la prise en charge. Le depistage de la FA combinait de maniere sequentielle la telemetrie, le Holter ECG prolonge et le Holter sous cutane. Les donnees cliniques…