A5056486779- Cardiac Arrhythmias and Treatments
- Cardiac electrophysiology and arrhythmias
- Connexins and lens biology
- Atrial Fibrillation Management and Outcomes
- Cardiovascular Function and Risk Factors
- Cardiac Imaging and Diagnostics
- Cardiac pacing and defibrillation studies
- Advanced MRI Techniques and Applications
- Congenital Heart Disease Studies
- Cardiovascular Effects of Exercise
- Cardiac Structural Anomalies and Repair
- Advanced X-ray and CT Imaging
- Cardiac Valve Diseases and Treatments
- Neuroscience and Neural Engineering
- Medical Imaging Techniques and Applications
- Cardiomyopathy and Myosin Studies
- Adipose Tissue and Metabolism
- Electrochemical Analysis and Applications
- Ion channel regulation and function
- ECG Monitoring and Analysis
- Congenital heart defects research
- Coronary Artery Anomalies
- Tissue Engineering and Regenerative Medicine
- Cell Adhesion Molecules Research
- Cardiovascular Disease and Adiposity
Centre de Recherche Cardio-Thoracique de Bordeaux
2015-2024
Electrophysiology and Heart Modeling Institute
2015-2024
Inserm
2015-2024
Université de Bordeaux
2014-2024
Hôpital Cardiologique du Haut-Lévêque
2019-2023
Institut de Chimie et des Matériaux Paris-Est
2023
Bibliothèque Nationale de France
2023
Physiologie et Médecine Expérimentale du Coeur et des Muscles
2023
Centre de Résonance Magnétique des Systèmes Biologiques
2023
Centre Hospitalier Universitaire de Bordeaux
2022-2023
Fifty-watt radiofrequency applications have proven to be safe and efficient for pulmonary vein isolation (PVI). However, as PV reconnection still occurs ablation catheter instability significantly contributes suboptimal lesion formation, a new capable of delivering 90 W 4 seconds only has been developed with the aim improving PVI outcomes. In this setting, we sought determine whether create transmural lesions without collateral damage experimentally they can safely improve procedures...
Background: Although proposed to facilitate pulmonary vein isolation (PVI), high-power ablation may favor extracardiac damage. Negative component abolition of the unipolar signal reflects lesion transmurality. The present study sought evaluate safety and efficacy using modification as a local end point. Methods High power standard were compared in 4 swine 100 consecutive patients referred for PVI. first 50 included control group (25–30 W) last (40–50 W). Atrial radiofrequency applications...
CXCR3 plays important roles in angiogenesis, inflammation, and cancer. However, the precise mechanism of regulation activity tumors is not well known. We focused on CXCR3-A conformation mechanisms controlling its trafficking investigated role CXCR3/LRP1 cross talk tumor cell invasion. Here we report that agonist stimulation induces an anisotropic response with conformational changes along longitudinal axis. internalized via clathrin-coated vesicles recycled by retrograde trafficking....
ABSTRACT Background Papillary muscle infarction (PMI) has been linked to significantly increased mortality and is associated with ventricular arrhythmias mitral regurgitation. Reference bright‐blood late gadolinium enhancement (LGE) imaging provides poor scar‐to‐blood contrast, making PMI visualization challenging. Black‐blood LGE overcomes this limitation by improving the blood‐scar contrast. Purpose To evaluate a recent co‐registered bright‐ (papillary localization) black‐blood (PMI...
Abstract Background Ultralow temperature cyroablation (ULTC) is designed to create focal, linear, and circumferential lesions. The aim of this study was assess the safety, efficacy, durability atrial ventricular ULTC lesions in preclinical large animal models. Methods Results system uses nitrogen near its liquid‐vapor critical point cool 11‐cm ablation catheters. catheter can be shaped specific anatomies using pre‐shaped stylets. used 11 swine four sheep (pulmonary vein isolation linear...
Brugada syndrome is a significant cause of sudden cardiac death (SCD), but the underlying mechanisms remain hypothetical. This study aimed to elucidate this knowledge gap through detailed ex vivo human heart studies. A was obtained from 15-year-old adolescent boy with normal electrocardiogram who experienced SCD. Postmortem genotyping performed, and clinical examinations were done on first-degree relatives. The right ventricle optically mapped, followed by high-field magnetic resonance...
Wideband phase-sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) enables myocardial scar imaging in implantable cardioverter defibrillators (ICD) patients, mitigating hyperintensity artifacts. To address subendocardial visibility challenges, a 2D breath-hold single-shot electrocardiography-triggered black-blood (BB) LGE sequence was integrated with wideband imaging, enhancing scar-blood contrast.
Background Papillary muscles are an important source of ventricular tachycardia (VT). Yet little is known about the role right (RV) endocavity structure, moderator band (MB). The aim this study was to determine characteristics MB that may predispose arrhythmia substrates. Methods Ventricular wedge preparations with intact MBs were studied from humans (n=2) and sheep (n=15; 40-50 kg). RV endocardium optically mapped, electrical recordings measured along septum. S1S2 pacing free wall, MB, or...
Abstract Aims The optimal interlesion distance (ILD) for 90 and 50 W radiofrequency applications with low ablation index (AI) values in the atria has not been established. Excessive ILDs can predispose to gaps, whereas restrictive procedural complications. present study sought, therefore, experimentally determine ILD W–4 s AI optimize catheter outcomes humans. Methods results Posterior intercaval lines were created eight adult sheep using CARTO QDOT-MICRO a temperature-controlled mode. In...
<h3>Objective</h3> The growing adult population with surgically corrected tetralogy of Fallot (TOF) is at risk arrhythmias and sudden cardiac death. We sought to investigate the contribution right ventricular (RV) structural electrophysiological remodelling arrhythmia generation in a preclinical animal model repaired TOF (rTOF). <h3>Methods results</h3> Pigs mimicking rTOF underwent MRI functional characterisation presented pulmonary regurgitation, RV hypertrophy, dilatation dysfunction...
Abstract The epicardial and endocardial surfaces of the heart are attractive targets to administer antiarrhythmic electrotherapies. Electrically stimulating wide areas small mammalian ventricles is straightforward given relatively scale their myocardial dimensions compared tissue space constant electrical field. However, it has yet be proven for larger hearts with properties ventricular closer humans. Our goal was address feasibility impact wide-area stimulation on large at different...
Cardiac fiber direction is an important factor determining the propagation of electrical activity, as well development mechanical force. In this article, we imaged ventricles several species with special attention to intraventricular septum determine functional consequences septal organization. First, identified a dual-layer organization orientation in ex vivo sheep hearts using diffusion tensor imaging at high field MRI. To expand scope results, investigated presence similar five mammalian...
Surgical repair of Tetralogy Fallot (TOF) is highly successful but may be complicated in adulthood by arrhythmias, sudden death, and right ventricular or biventricular dysfunction. To better understand the molecular cellular mechanisms these delayed cardiac events, a chronic animal model postoperative TOF was studied using microarrays to perform transcriptomic studies. The experimental study included 12 piglets (7 rTOF 5 controls) that underwent surgery at age 2 months were further after 23...
The purpose of this study was to introduce and evaluate a novel two-dimensional wideband black-blood (BB) LGE sequence, incorporating inversion recovery, T2 preparation, non-rigid motion correction (MOCO) reconstruction, improve myocardial scar detection address artifacts associated with implantable cardioverter defibrillators (ICDs). MOCO free-breathing BB-LGE sequence tested on sheep ischemic in 22 patients cardiac disease, including 15 implants, at 1.5 T. Wideband compared conventional...
Background: Ventricular arrhythmias are frequent in patients with repaired tetralogy of Fallot (rTOF), but their origin and underlying mechanisms remain unclear. In this study, the involvement left ventricular (LV) electrical structural remodeling was assessed an animal model mimicking rTOF sequelae. Methods: Piglets underwent a repair–like surgery (n=6) or were sham operated (Sham, n=5). Twenty-three weeks post-surgery, cardiac function vivo by magnetic resonance imaging....
While the microstructure of left ventricle (LV) has been largely described, only a few studies investigated right ventricular insertion point (RVIP). It was accepted that aggregate cardiomyocytes organization much more complex due to intersection cavities but precise structural characterization in human heart lacking even if clinical phenotypes related wall stress or arrhythmia were observed this region. MRI-derived anatomical imaging (150 µm3) and diffusion tensor (600 performed large...
Abstract Modifications of the myocardial architecture can cause abnormal electrical activity heart. Fibro-fatty infiltrations have been implicated in various cardiac pathologies associated with arrhythmias and sudden death, such as arrhythmogenic right ventricular cardiomyopathy (ARVC). Here, we report development an MRI protocol to observe these modifications at 9.4 T. Two fixed ex vivo human hearts, one healthy ARVC, were imaged Iterative decomposition echo asymmetry least-square...
Abstract Underlying electrical propagation in the heart and potentially fatal arrhythmia is cardiac microstructure. Despite critical role of muscle architecture, a non-destructive approach to examine not only myocyte orientation, but cellular arrangement laminar organization lacking hearts from translational animal models humans. X-ray micro computed tomography using contrast enhancing agents achieves three-dimensional images at near-histological resolutions. However, imaging large mammalian...
Structural remodeling is a common consequence of chronic pathological stresses imposed on the heart. Understanding architectural and compositional properties diseased tissue critical to determine their interactions with arrhythmic behavior. Microscale remodeling, below clinical resolution, emerging as an important source lethal arrhythmia, high prevalence in young adults. Challenges remain obtaining imaging contrast at sufficient microscale resolution for preclinical models, such large...
Abstract Objectives We investigate the possibility to exploit high-field MRI acquire 3D images of Purkinje network which plays a crucial role in cardiac function. Since fibers (PF) have distinct cellular structure and are surrounded by connective tissue, we investigated conventional contrast mechanisms along with magnetization transfer (MT) imaging technique improve image between ventricular structures differing macromolecular content. Methods Three fixed porcine samples were used...
Gap junction channels (GJC) ensure the direct electrical and chemical cell-to-cell communication. In heart their biophysical properties are considered as a key factor for regulating impulse propagation through cardiac network ensuring coordinated atrial ventricular contractions. GJC made of connexins Cx43, Cx40, Cx45 Cx30.2 that display distinct specific expression patterns in differentiated myocytes conduction system. The dysfunction remodeling, i.e. altered localization, believed to be...
The cardiac action potential (AP) propagation is regulated to permit the coordinated and rhythmic atrial ventricular contractions. This regulation requires passive active factors. A key factor gap junctions, which ensure a direct pathway for electrical biochemical signaling. They are clusters of intercellular junction channels (GJC) made two hemichannels docked in membrane adjacent cells, composed six connexins (Cxs). Their distinct properties considered as regulating AP. Four Cxs, Cx40,...