The Maintenance of Human Atrial Fibrillation
Atrial fibrillation (AF) is the most prevalent heart rhythm disorder in the United States, affecting 2.5 million individuals in whom it may cause stroke, palpitations, heart failure, and even death. Unfortunately, therapy for AF is limited. Anti-arrhythmic or rate-controlling drugs are poorly tolerated, with frequent side effects and do not reduce stroke risk. Ablation is an emerging, minimally invasive therapy that has attracted considerable attention because it may eliminate AF. Unfortunately, AF ablation is technically challenging, with a success of only 50-70% (versus >90% for other arrhythmias) and serious risks. A major cause of these limitations is that the mechanisms for human AF are not known and thus ablation cannot be directed to them. As a result, AF ablation is empiric and results in extensive destruction of the atrium.
This project will perform research to better understand AF and determine if abnormal activity in small regions or more widespread regions of the heart cause AF. By performing these studies in patients during clinical procedures, this project may lead to a paradigm shift in the understanding and treatment of AF.
Aperçu de l'étude
Statut
Les conditions
Description détaillée
This proposal will test the hypothesis that spatially localized sites maintain ongoing human AF, so that ablation at these drivers may eliminate AF on long-term followup. The investigators will study atrial fibrillation in patients undergoing ablation, to identify regions that may be sustaining AF, then ablate at them.
The study design will be to identify sites that may be maintaining AF, using mapping of AF prior to ablation. Once identified, these sites will be targeted for ablated using traditional methods. This process will be repeated up to six times. The locations of these sites will be recorded, and compared to traditional sites for AF ablation, including the pulmonary veins and left atrial roof. They will also be studied for the presence of complex fractionated electrograms and high dominant frequency.
Patients with persistent, long standing persistent, and paroxysmal AF will be included, and patients will then be followed for 6-12 months.
Type d'étude
Inscription (Réel)
Contacts et emplacements
Lieux d'étude
-
-
California
-
San Diego, California, États-Unis, 92103
- University of California San Diego Medical Center
-
San Diego, California, États-Unis, 92161
- Veterans Affairs San Diego Medical Center
-
-
Critères de participation
Critère d'éligibilité
Âges éligibles pour étudier
Accepte les volontaires sains
Sexes éligibles pour l'étude
Méthode d'échantillonnage
Population étudiée
La description
INCLUSION CRITERIA for STUDY SUBJECTS:
- patients undergoing electrophysiology study (EPS) for ablation of (a) paroxysmal AF (non-rheumatic) whose AF episodes self-terminate in < 7 days, or (b) persistent AF (non-rheumatic) whose AF episodes last >or= 7 days but terminate with DC cardioversion or anti-arrhythmic drugs and do not recur within 24 hours.
- AF patients must have failed >or= 1 anti-arrhythmic drug
INCLUSION CRITERIA for ALL SUBJECTS:
- will have a full evaluation focusing on diabetes mellitus, hypertension, coronary disease, left ventricular ejection fraction (LVEF). We will document whether AF relates to times of vagal activity (meals or sleep) or exercise. We will record the use of drugs affecting the renin-aldosterone-angiotensin system (RAAS) and statins, that may protect against atrial fibrosis and AF. We will document serum potassium level, since slight elevations slow CV in vitro. We will record 12-lead ECG and echocardiography for left atrial diameter, and stress test and/or coronary angiography if indicated.
- will have event monitor recordings with daily transmissions for at least one week to document AF burden (study subjects) or exclude AF (control subjects).
- must have with-held amiodarone for > 30 days and other anti-arrhythmic drugs for > 5 half-lives.
EXCLUSION CRITERIA FOR ALL SUBJECTS:
- active coronary ischemia in the past year, since the protocol uses isoproterenol
- rheumatic valve disease, that leads to distinct AF and increases thromboembolic risk
- prior ablation or cardiac surgery, that alters atrial electrophysiology
- LA clot or dense contrast on TEE
- deranged serum electrolytes, and K+ outside 4.0-5.0 mmol/l
- left atrial diameter > 60 mm
- LVEF < 40% or New York Heart Association heart failure > Class II, to exclude distinct, heart-failure related remodeling
- thrombotic disease, venous filters, transient ischemic attack or cerebrovascular accident, to minimize additional risk
- pregnancy, to minimize fluoroscopy. As part of routine clinical care, all female patients of childbearing age receive a ß-HCG pregnancy test. Any who test positive will not be included in the research study
- inability or unwillingness to provide informed consent
Plan d'étude
Comment l'étude est-elle conçue ?
Détails de conception
Cohortes et interventions
Groupe / Cohorte |
|---|
|
Intervention
Patients with persistent, long standing persistent and paroxysmal AF, who will receive ablation at sites that potentially maintain human AF.
|
|
Control
Patients with persistent, long standing persistent and paroxysmal AF, who receive conventional ablation as determined by the operator at each site, and based upon Heart Rhythm Society guidelines.
|
Que mesure l'étude ?
Principaux critères de jugement
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
|
recurrence of atrial fibrillation
Délai: 1 year
|
recurrence of AF measured using clinical follow-up with implanted devices in all patients who consent
|
1 year
|
Collaborateurs et enquêteurs
Parrainer
Collaborateurs
Les enquêteurs
- Chercheur principal: Sanjiv Narayan, MD, PhD, University of California, San Diego
Dates d'enregistrement des études
Dates principales de l'étude
Début de l'étude (Réel)
Achèvement primaire (Réel)
Achèvement de l'étude (Réel)
Dates d'inscription aux études
Première soumission
Première soumission répondant aux critères de contrôle qualité
Première publication (Estimation)
Mises à jour des dossiers d'étude
Dernière mise à jour publiée (Réel)
Dernière mise à jour soumise répondant aux critères de contrôle qualité
Dernière vérification
Plus d'information
Termes liés à cette étude
Termes MeSH pertinents supplémentaires
Autres numéros d'identification d'étude
- 101311
- K24HL103800 (Subvention/contrat des NIH des États-Unis)
Ces informations ont été extraites directement du site Web clinicaltrials.gov sans aucune modification. Si vous avez des demandes de modification, de suppression ou de mise à jour des détails de votre étude, veuillez contacter register@clinicaltrials.gov. Dès qu'un changement est mis en œuvre sur clinicaltrials.gov, il sera également mis à jour automatiquement sur notre site Web .