Search results for "FIBRILLATION"
showing 10 items of 509 documents
Cholesterol-adjusted vitamin E serum levels are associated with cardiovascular events in patients with non-valvular atrial fibrillation.
2013
Non-valvular atrial fibrillation is associated with an increase in thromboembolism, i.e. stroke, and atherosclerotic events, i.e. myocardial infarction. Vitamin E possesses anti-coagulant as well as anti-atherosclerotic properties. Our aim was to assess whether vitamin E is associated with cardiovascular events in patients with non-valvular atrial fibrillation.Serum levels of cholesterol-adjusted vitamin E were measured in 1012 patients with non-valvular atrial fibrillation. Patients were followed for a mean time of 27.0 months, and cardiovascular events, such as cardiovascular death and fatal and nonfatal stroke or myocardial infarction, were recorded.During the follow-up period, cardiovas…
Nerves projecting from the intrinsic cardiac ganglia of the pulmonary veins modulate sinoatrial node pacemaker function
2013
Rationale: Autonomic nerves from sinoatrial node (SAN) ganglia are known to regulate SAN function. However, it is unclear whether remote pulmonary vein ganglia (PVG) also modulate SAN pacemaker rhythm. Objective: To investigate whether in the mouse heart PVG modulate SAN function. Methods and Results: In hearts from 45 C57BL and 7 Connexin40+/GFP mice, we used tyrosine-hydroxylase (TH) and choline-acetyltransferase (ChAT) immunofluorescence labeling to characterize adrenergic and cholinergic elements, repectively, within the PVG and SAN. PVG project postganglionic nerves to the SAN. TH and ChAT stained nerves, enter the SAN as an extensive, dense mesh-like neural network. Neurons in PVG are…
Ischemic stroke risk during long-term follow up in patients with successful catheter ablation for atrial fibrillation in Korea
2018
The interruption of oral anticoagulation therapy (OAC) after CA of atrial fibrillation (AF) is controversial. The purpose of this study was to evaluate the relationship between successful long-term outcomes of catheter resection and SR maintenance and ischemic stroke risk in Korea. We studied 1,548 consecutive patients who were followed up for more than 2 years after CA of AF. We investigated the incidence of ischemic stroke during long-term follow-up. Compared to the AF recurrence group (n = 619), the sinus rhythm (SR) maintenance group (n = 929) had more paroxysmal AF (74.6% versus 44.4%, p<0.001), smaller LA size (39.9±5.7mm versus 42.3±6.0mm, p<0.001), and younger age (54.2±10.9 years v…
Three dimensional reconstruction to visualize atrial fibrillation activation patterns on curved atrial geometry
2021
BackgroundThe rotational activation created by spiral waves may be a mechanism for atrial fibrillation (AF), yet it is unclear how activation patterns obtained from endocardial baskets are influenced by the 3D geometric curvature of the atrium or ‘unfolding’ into 2D maps. We develop algorithms that can visualize spiral waves and their tip locations on curved atrial geometries. We use these algorithms to quantify differences in AF maps and spiral tip locations between 3D basket reconstructions, projection onto 3D anatomical shells and unfolded 2D surfaces.MethodsWe tested our algorithms in N = 20 patients in whom AF was recorded from 64-pole baskets (Abbott, CA). Phase maps were generated by…
Cardiac sources of cerebral embolism in people with migraine
2021
Background and purpose Whether the reported association between migraine with aura (MA) and cardioembolic stroke may be explained by a higher rate of atrial fibrillation (AF) or by other potential cardiac sources of cerebral embolism remains to be determined.Methods In the setting of a single centre cohort study of consecutive patients with acute brain ischaemia stratified by migraine status, the association between AF as well as patent foramen ovale (PFO) and migraine was explored.Results In all, 1738 patients (1017 [58.5%] men, mean age 67.9 +/- 14.9 years) qualified for the analysis. Aging was inversely associated with migraine, whilst women had a >3-fold increased disease risk (odds …
Non-valvular Atrial Fibrillation in CKD: Role of Vitamin K Antagonists and Direct Oral Anticoagulants. A Narrative Review
2021
Atrial fibrillation (AF) is the most common arrhythmia in chronic kidney disease (CKD), with a close bidirectional relationship between the two entities. The presence of CKD in AF increases the risk of thromboembolic events, mortality and bleeding. Vitamin K antagonists (VKA) have been the mainstay of treatment for the prevention of thromboembolic events in AF until recently, with confirmed benefits in AF patients with stage 3 CKD. However, the risk-benefit profile of VKA in patients with AF and stages 4–5 CKD is controversial due to the lack of evidence from randomized controlled trials. Treatment with VKA in CKD patients has been associated with conditions such as poorer anticoagulation q…
Management of Direct Oral Anticoagulants in Patients with Atrial Fibrillation Undergoing Cardioversion
2019
Atrial fibrillation the most common cardiac arrhythmia. Its incidence rises steadily with each decade, becoming a real “epidemic phenomenon”. Cardioversion is defined as a rhythm control strategy which, if successful, restores normal sinus rhythm. This, whether obtained with synchronized shock or with drugs, involves a periprocedural risk of stroke and systemic embolism which is reduced by adequate anticoagulant therapy in the weeks before or by the exclusion of left atrial thrombi. Direct oral anticoagulants are safe, manageable, and provide rapid onset of oral anticoagulation; they are an important alternative to heparin/warfarin from all points of view, with a considerable reduction in b…
CATHAR : CATHeter for ARRhythmias : determination of depth of burned biological tissues with microwave
2015
Cardiac arrhythmia substrates may be treated by intracardiac ablations which consist in burning specific atrial or ventricular endocardial substrates. Created lesions which are not transmural may be responsible for arrhythmia recurrences. To date, the depth of the lesion inside the endocardium can't be assessed accurately during the procedures. Our experimental work has focused on microwave characterization of biological tissues (in vitro) to assess the burn depth. Using a reflection technique with a coaxial probe in contact with tissues, measurements were made over a wide frequency range (100 MHz to 6 GHz). The measured reflection coefficient is known to be directly related to the dielectr…
In Situ Characterization of Hfq Bacterial Amyloid: A Fourier-Transform Infrared Spectroscopy Study
2019
Hfq is a bacterial protein that regulates gene expression at the post-transcriptional level in Gram-negative bacteria. We have previously shown that Escherichia coli Hfq protein, and more precisely its C-terminal region (CTR), self-assembles into an amyloid-like structure in vitro. In the present work, we present evidence that Hfq unambiguously forms amyloid structures also in vivo. Taking into account the role of this protein in bacterial adaptation and virulence, our work opens possibilities to target Hfq amyloid self-assembly and cell location, with potential to block bacterial adaptation and treat infections. Fil: Partouche, David. Centre National de la Recherche Scientifique; Francia. …
Detailed Anatomical and Electrophysiological Models of Human Atria and Torso for the Simulation of Atrial Activation
2015
Atrial arrhythmias, and specifically atrial fibrillation (AF), induce rapid and irregular activation patterns that appear on the torso surface as abnormal P-waves in electrocardiograms and body surface potential maps (BSPM). In recent years both P-waves and the BSPM have been used to identify the mechanisms underlying AF, such as localizing ectopic foci or high-frequency rotors. However, the relationship between the activation of the different areas of the atria and the characteristics of the BSPM and P-wave signals are still far from being completely understood. In this work we developed a multi-scale framework, which combines a highly-detailed 3D atrial model and a torso model to study th…