Screening of Paroxysmal Atrial Fibrillation after Ischemic Stroke: 48-Hour Holter Monitoring versus Prolonged Intermittent ECG Recording

Aims. Screening of paroxysmal atrial fibrillation (PAF) after ischemic stroke and TIA is important. The ideal method is not known and studies of intermittent screening methods in particular are lacking. In this retrospective study we compared a shorter continuous screening method with an intermittent screening method. Methods. Since early 2011 our stroke unit has used two different methods of screening: either a 48-hour continuous screening with Holter monitor or a 21-day twice daily intermittent screening with a hand-held ECG recorder. Through the Swedish National Stroke Registry and medical records reviewing all screening episodes between 2011-02-01 and 2013-01-31 were collected and analysed. ？？Results. Of 386 screenings, 26 screenings were excluded leaving 360 screenings for the final analysis of which 114 screenings were made with hand-held ECG recorder and 246 with Holter monitoring. No significant difference between the groups concerning basic characteristics was observed. In the hand-held ECG recorder group a total of 13 PAF screenings (11.4%) were detected compared with 7 (2,8%) in the Holter group ( ). Conclusions. A prolonged intermittent screening is a better method than a shorter continuous screening in terms of detecting PAF after ischemic stroke and TIA. 1. Introduction Stroke is the third most common cause of death in most Western populations after coronary heart disease and cancer. The majority of these strokes are ischemic strokes for which atrial fibrillation (AF) is a major risk factor, conferring a fivefold increased risk [1]. This increased risk appears to be the same regardless of whether the atrial fibrillation is permanent or paroxysmal [2, 3]. Importantly, a diagnosis of atrial fibrillation after stroke usually results in secondary prophylaxis with oral anticoagulants, a highly effective treatment with a relative risk reduction of recurrence of 65% compared with placebo [4]. Furthermore, it has been suggested that paroxysmal atrial fibrillation (PAF) may be an underestimated cause of ischemic stroke [5, 6]. With the high efficacy of oral anticoagulants in mind, it is crucial to identify all significant PAF in order to achieve the best possible secondary prevention. Since PAF often is asymptomatic, it requires screening to be diagnosed [7]. In addition, screening for PAF after ischemic stroke was in a recent model shown to be cost effective [8]. Up until now in-patient continuous cardiac monitoring has been the most common method to identify PAF, usually for the first 24 or 48 hours after admission. The longer the screening is