Abstract 19599: Continuous versus 3 Weeks Intermittent ECG Monitoring for Detection of Subclinical Atrial Fibrillation in High-Risk Patients

• Published in: Circulation (New York, N.Y.) Vol. 134; no. Suppl_1 Suppl 1; p. A19599
• Main Authors: Philippsen, Tine J, Christensen, Lene S, Hansen, Michael G, Brandes, Axel
• Format: Journal Article
• Language: English
• Published: by the American College of Cardiology Foundation and the American Heart Association, Inc 11.11.2016
• ISSN: 0009-7322; 1524-4539

BackgroundAtrial fibrillation (AF) often occurs in a subclinical form, which makes it difficult to detect. The effect of continuous versus intermittent rhythm monitoring to detect subclinical AF is poorly investigated in patients with age ≥ 65 years, hypertension (HTN) and diabetes mellitus (DM). This group of patients has increased risk of developing AF and in addition a high thromboembolic risk, if AF is present.PurposeTo investigate whether continuous monitoring using an implantable loop recorder (ILR) detects more episodes of subclinical AF than daily intermittent monitoring for 3 weeks in high-risk patients.MethodsA total of 82 outpatients ≥ 65 years (median age 71.3 years (IQR 67.4-75.1)) with DM and HTN, and no history of AF or any other cardiovascular disease, were consecutively included. All patients received an ILR and were followed for a median of 342 days (IQR 208-456). To compare continuous monitoring with intermittent monitoring, we used the device to simulate a 2 minutes daily handheld ECG data collection for 3 weeks starting one month after ILR insertion. The primary end-point was AF with a minimum duration of two minutes. Oral anticoagulation (OAC) treatment was initiated upon an AF episode lasting ≥ 6 minutes.ResultsDuring follow-up 17 patients (20.7 %) were found to have subclinical AF detected by the ILR with a median time to first detected episode of 126 days (IQR 56-260) from inclusion. Thirteen patients (15.9 %) had AF ≥ 6 minutes and initiated OAC treatment. On the contrary, only 2 patients (2.4 %) also presented with AF episodes on the simulated 3 weeks intermittent monitoring (p=0.04). All detected episodes were completely asymptomatic.ConclusionsContinuous monitoring with ILR detected significantly more AF episodes than 3 weeks daily intermittent monitoring. The incidence of subclinical AF in this group of patients was surprisingly high.