Abstract 17142: A Real-world Experience For Implantable Loop Recorder Monitoring To Detect Subclinical Atrial Fibrillation In Patients With Cryptogenic Stroke

IntroductionCryptogenic stroke represents approximately 30% of all ischemic strokes. Clinical studies have shown that implantable loop recorders (ILRs) may identify subclinical AF in up to 1/3 of these patients. However, there is variation in the literature of the yield of these devices.HypothesisThose implanted with ILR for cryptogenic stroke will show an AF detection rate comparable to that of prior clinical studies. Analysis of electrocardiograms may help identify those at higher risk of AF detection.MethodsA retrospective chart review was conducted of all patients who presented with cryptogenic stroke and received an ILR at an academic medical center from 2015-2017. There were no exclusion criteria among such patients. The electronic health record and remote monitoring were used to identify occurrence of AF and timing to first event. Baseline demographics, co-morbidities, electrocardiogram (ECG) and echocardiogram characteristics were analyzed for predictors of AF detection.ResultsA total of 178 patients who received ILRs for cryptogenic stroke were included. Overall, 35 (19.6%) were found to have AF detected on ILR (figure 1). Mean follow-up duration was 365 days with a median time to detection of 131 days. The median duration of AF detected was 120 minutes. The only demographic variable predictive of AF detection was advanced age (p = 0.001). ECG findings of premature atrial contractions (PACs), and p wave dispersion (PWD) > 40 ms were also found to be predictive (p = 0.04, p < 0.001, respectively).ConclusionsApproximately 20% of patients presenting to our facility with cryptogenic stroke were found to have AF with ILR surveillance. Advanced age, as well as ECG findings of PACs and increased PWD may help to predict those at higher risk of AF detection. Given the high yield and relatively prolonged median time to detection (131 d) in this population, earlier ILR implantation may be warranted in certain high risk groups.