Abstract W P194: Improved Efficacy of ICM Detection of Atrial Fibrillation in Cryptogenic Stroke Patients with MRI-Defined Infarcts: Preliminary Results from the SPIDER Registry
Introduction: Recent trials have demonstrated the efficacy of the implantable cardiac monitor (ICM) in detecting atrial fibrillation (AF) in cryptogenic stroke (CS) patients. However, these trials have included patients with TIAs or no CT or MRI imaging of the brain. We hypothesized that the AF detection rate in CS patients would be improved by requiring the presence of an embolic-appearing infarct on MRI.
Methods: All CS patients within the Promedica Stroke Network were considered for inclusion in the SPIDER (Stroke Prevention through the Improved Detection of AF) registry. All patients were monitored by inpatient telemetry for AF for a minimum of 48 hours, and received brain MRI with or without angiography. Patients with no AF, a negative transesophageal echo for ASD/PFO, and an embolic-appearing MRI infarct (wedge infarct, multiple vascular distributions) were offered an ICM (Reveal or Reveal LINQ™) for AF detection (minimum of 10 seconds).
Results: 64 patients have been enrolled to date and followed for 223 days. Mean age was 66.9 ± 12.8 years and 40.6% were female with a median NIH stroke score of 5.2 on presentation. AF episodes were detected in 11 patients, resulting in an AF detection rate of 17.2% and a median time to AF detection of 35 days. While both mean follow-up and time to AF detection were comparable to the data from CRYSTAL-AF (6 months, 41 days), AF detection rate was increased nearly two-fold.
Conclusions: Here we show that restricting ICM implantation for AF detection in CS patients to those with MRI-defined embolic-appearing infarcts improves efficacy, with an increase of 8.3% in detection at six months, when adjusted for follow-up time. Explanations for this higher detection rate might include a slightly higher age (66.9 vs 61.5 years of age), a more liberal cutoff for AF (10 vs 30 seconds), and, likely, a more highly selected patient population. Such an approach might both improve access to this important technology and help preserve health care resources.
Author Disclosures: K. Joseph: Speakers' Bureau; Modest; Medtronic. S. Wanjiku: None. M. Jumaa: None. M. Richards: Speakers' Bureau; Modest; Medtronic, Biotronik, Boehringer-Ingleheim. Speakers' Bureau; Significant; Janssen, Pfizer, Bristol-Myers Squibb. Consultant/Advisory Board; Modest; Biotronik, Boston Scientific.
- © 2015 by American Heart Association, Inc.