Stroke Stop Study: editorial comment

Abstract

This editorial refers to ‘Population screening of 75- and 76-year-old men and women for silent atrial fibrillation (STROKESTOP)’ by L. Friberg et al. , on page 135 The paper by Friberg et al. in this issue of the journal describes an ongoing study to evaluate the use of intermittent external monitoring to detect ‘silent’ atrial fibrillation (AF) in a huge (25 000) group of 75 and 76 year olds in Sweden.1 The hypothesis is that if silent AF is detected early and treated medically with oral anticoagulation (OAC), that strokes can be prevented, lives can be saved, and it will be proven that screening for silent AF is cost-effective. Interest in silent AF began over 10 years ago with the publication of several scientific papers showing an association between implanted device detection of atrial arrhythmias and increased risks of death and more specifically stroke.2,3 With the advent of sophisticated pacemakers and implantable cardioverter defibrillators (ICDs) with extensive memory capability, it became clear that many patients were having AF episodes that were previously unrecognized. Over the last 10 years a great effort has been made to try to determine the clinical significance of these atrial arrhythmia episodes (silent AF).4,5 Specifically, how long does an AF episode have to last to increase the risk of stroke enough to warrant OAC with its inherent increased risks of bleeding? Do these silent AF episodes have the same clinical risk of stroke as manifest episodes of AF? Most of the prior studies in this field have been done in patients who have an implanted pacemaker or ICD that was implanted for primary indications, and the study of atrial arrhythmias was a secondary intention. The Stroke Stop Study is planned to look for AF episodes as a primary indication for …