Abstract 18233: Implantable Loop Recorder Monitoring is Useful in Detecting a High Incidence of Previously Unrecognized Atrial Fibrillation in Hemodialysis Patients. Preliminary Data From the Monitoring in Dialysis (MiD) Study
Introduction: Patients with end stage renal disease have a high incidence of stroke and studies have shown that even short durations of atrial fibrillation (AFib) in this population increase stroke risk.
Hypothesis: Implantable loop recorder monitoring will provide useful information to guide stroke risk reduction by detecting and quantifying AFib in hemodialysis (HD) pts.
Methods: MiD is a prospective multi-center study to characterize arrhythmias in maintenance HD pts with an implantable loop recorder (ILR) over a 12mo period. The ILR device used detects AFib episodes based on incoherence in adjacent R-R intervals, with previous validation against simultaneous Holter monitoring showing 92% sensitivity and 80% positive predictive value for AFib episodes lasting ≥6 minutes.
Results: Follow-up is available for 45 pts [mean follow-up 6.4mo (0.6-12.0mo), mean age 56yrs (27-76yrs), 36% female]. 1294 AFib episodes ≥6 minutes were detected in 19/45 pts (42%), occurring at a mean rate of 13.7 (95% CI 6.1-30.9) events per patient month in these 19 pts. Minimum total duration of AFib in these 19 pts was 20 minutes with 13/19 pts (68%) having > 100 minutes and 8/19 pts (42%) having >20 hours of ILR-detected Afib during follow-up. Only 5/19 pts (26%) with Afib episodes ≥6 minutes had any prior history of Afib and 13/19 pts (68%) were not on anticoagulation (AC) at study entry. There were also 2 pts with Afib episodes ≥6 minutes with a prior CVA or TIA who had not previously been diagnosed with Afib and were not on AC at study entry. All 19 pts (100%) with Afib episodes ≥6 minutes had CHADS2 scores ≥1 and 15/19 pts (79%) had CHADS2 scores ≥2, including 12/13 pts (92%) not on AC. ILR surveillance thus identified 12/45 pts (27%) in the cohort who were not on AC at enrollment with the potential to derive significant stroke risk reduction with AC.
Conclusions: Afib is common and often undiagnosed in HD pts with 42% of MiD patients having at least one sustained episode (≥6 minutes) and only 11% of these patients having any prior history. ILR surveillance has value in identifying patients at risk for stroke in whom anticoagulation may be beneficial. With improvement in ILR technology with respect to size and wireless capability, clinicians should have a low tolerance to evaluate HD patients for Afib.
Author Disclosures: B.A. Koplan: Other Research Support; Modest; medtronic, boston scientific, zoll medical. Consultant/Advisory Board; Modest; st. jude medical. S.A. Tombul: None. J.A. Tumlin: Other Research Support; Modest; Questcor Pharmaceuticals, Liliy Pharmaceuticls, Abott Pharmaceuticals, Medtronic, Genzyme. Consultant/Advisory Board; Modest; Questcor Pharmaceuticls, Liliy Pharmaceuticals, Abbott Pharmaceuticals. D.M. Charytan: Other Research Support; Modest; Medtronic. Consultant/Advisory Board; Modest; Kerryx, Tengion, Affymax, Medtronic, RAS Scientific, Boehringer Ingelheim.
- © 2014 by American Heart Association, Inc.