Supplementary Material for: Detection of Atrial Fibrillation After Ischemic Stroke with an Insertable Cardiac Monitor: A Systematic Review and Individual Patient Data Meta-Analysis of Randomised Clinical Trials

Objective: In ischemic stroke patients, we compared the use of insertable cardiac monitor (ICM) versus non-ICM methods of cardiac monitoring on the incidence of atrial fibrillation (AF) detection and other clinical outcomes. Background: Current guidelines recommend the routine use of 12-lead electrocardiography or Holter monitoring for AF detection after ischemic stroke. Recent randomised controlled trials have investigated the impact of ICM versus non-ICM methods of cardiac monitoring for AF detection in this population. However, precise recommendations for monitoring post-stroke AF are lacking; including the optimal timing, duration, and method of electrocardiography monitoring. Methods: A systematic search was conducted on Embase and PubMed from database inception until 27 October 2022 to include randomised controlled trials that compared ICM with non-ICM methods of cardiac monitoring for post-stroke AF detection. This yielded 3 randomised controlled trials with a combined cohort of 1231 patients with a recent ischemic stroke. Individual patient data (IPD) was then reconstructed from Kaplan–Meier curves and analysed using the shared-frailty Cox model. An aggregate data meta-analysis was conducted for 1231 patients across all 3 studies for outcomes that could not be reconstructed using IPD. Results: One-stage meta-analysis demonstrated an increase in the hazard ratio (HR 6.01, 95% CI 3.40-10.60; p<0.001) of AF detection in patients undergoing monitoring via ICM compared to standard care. Aggregate data meta analysis revealed a significant increase in initiation of anticoagulation (OR 3.09, 95% CI 2.05 - 4.66; p<0.00001) in the ICM group. However, no significant differences in the incidence of recurrent ischemic stroke, transient ischemic attack or death were found. Conclusions: In this meta-analysis, we found that the use of ICM increased the detection rate of post-stroke AF and the rate of anticoagulation initiation. However, this did not translate into a reduced incidence of recurrent ischemic stroke.