title: Epicardial fat and atrial fibrillation: current evidence, potential mechanisms, clinical implications, and future directions.
abstract: Obesity is increasingly recognized as a major modifiable determinant of atrial fibrillation (AF). Although body mass index and other clinical measures are useful indications of general adiposity, much recent interest has focused on epicardial fat, a distinct adipose tissue depot that can be readily assessed using non-invasive imaging techniques. A growing body of data from epidemiological and clinical studies has demonstrated that epicardial fat is consistently associated with the presence, severity, and recurrence of AF across a range of clinical settings. Evidence from basic science and translational studies has also suggested that arrhythmogenic mechanisms may involve adipocyte infiltration, pro-fibrotic, and pro-inflammatory paracrine effects, oxidative stress, and other pathways. Despite these advances, however, significant uncertainty exists and many questions remain unanswered. In this article, we review our present understanding of epicardial fat, including its classification and quantification, existing evidence implicating its role in AF, potential mechanisms, implications for clinicians, and future directions for research.
authors.affiliation: Clinical Trial Service Unit and Epidemiological Studies Unit, University of Oxford, Oxford, UK.
authors.forename: Christopher X
authors.initials: CX
authors.lastname: Wong
authors.affiliation: Department of Cardiology, Flinders Medical Centre & Flinders University, Flinders Drive, Bedford Park, Adelaide, South Australia 5043, Australia.
authors.forename: Anand N
authors.initials: AN
authors.lastname: Ganesan
authors.affiliation: Department of Cardiology, Flinders Medical Centre & Flinders University, Flinders Drive, Bedford Park, Adelaide, South Australia 5043, Australia.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Selvanayagam
mesh_terms: D017667:Adipocytes / Q000502:physiology; D000273:Adipose Tissue / Q000473:pathology / Q000502:physiology*; D050154:Adiposity / Q000502:physiology; D001281:Atrial Fibrillation / Q000209:etiology* / Q000473:pathology / Q000628:therapy; D001342:Autonomic Nervous System Diseases / Q000209:etiology / Q000473:pathology; D005544:Forecasting; D006801:Humans; D009206:Myocardium / Q000473:pathology; D009765:Obesity / Q000150:complications / Q000473:pathology; D018384:Oxidative Stress / Q000502:physiology; D010496:Pericardium / Q000473:pathology*; D018570:Risk Assessment; D035703:Therapies, Investigational; D015431:Weight Loss / Q000502:physiology
keywords: Adiposity; Atrial fibrillation; Body mass index; Cardiac magnetic resonance imaging; Computed tomography; Echocardiography; Epicardial fat; Obesity; Pericardial fat; Visceral adipose tissue; Waist circumference; Waist-to-hip ratio