title: Detection of previously undiagnosed atrial fibrillation in patients with stroke risk factors and usefulness of continuous monitoring in primary stroke prevention.
abstract: The detection of undiagnosed atrial tachycardia/atrial fibrillation (AT/AF) among patients with stroke risk factors could be useful for primary stroke prevention. We analyzed newly detected AT/AF (NDAF) using continuous monitoring in patients with stroke risk factors but without previous stroke or evidence of AT/AF. NDAF (AT/AF >5 minutes on any day) was determined in patients with implantable cardiac rhythm devices and ≥1 stroke risk factors (congestive heart failure, hypertension, age ≥75 years, or diabetes). All devices were capable of continuously monitoring the daily cumulative time in AT/AF. Of 1,368 eligible patients, NDAF was identified in 416 (30%) during a follow-up of 1.1 ± 0.7 years and was unrelated to the CHADS(2) score (congestive heart failure, hypertension [blood pressure consistently >140/90 mm Hg or hypertension treated with medication], age ≥75 years, diabetes mellitus, previous stroke or transient ischemic attack). The presence of AT/AF >6 hours on ≥1 day increased significantly with increased CHADS(2) scores and was present in 158 (54%) of 294 patients with NDAF and a CHADS(2) score of ≥2. NDAF was sporadic, and 78% of patients with a CHADS(2) score of ≥2 with NDAF experienced AT/AF on <10% of the follow-up days. The median interval to NDAF detection in these higher risk patients was 72 days (interquartile range 13 to 177). In conclusion, continuous monitoring identified NDAF in 30% of patients with stroke risk factors. In patients with NDAF, AT/AF occurred sporadically, highlighting the difficulty in detecting paroxysmal AT/AF using traditional monitoring methods. However, AT/AF also persisted for >6 hours on ≥1 days in most patients with NDAF and multiple stroke risk factors. Whether patients with CHADS(2) risk factors but without a history of AF might benefit from implantable monitors for the selection and administration of anticoagulation for primary stroke prevention merits additional investigation.
authors: Medtronic Inc., Minneapolis, Minnesota, USA. paul.david.ziegler@medtronic.com
authors: Paul D
authors: PD
authors: Ziegler
authors: Taya V
authors: TV
authors: Glotzer
authors: Emile G
authors: EG
authors: Daoud
authors: Daniel E
authors: DE
authors: Singer
authors: Michael D
authors: MD
authors: Ezekowitz
authors: Robert H
authors: RH
authors: Hoyt
authors: Jodi L
authors: JL
authors: Koehler
authors: James
authors: J
authors: Coles
authors: D George
authors: DG
authors: Wyse
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D058406:Cardiac Resynchronization Therapy / Q000379:methods; D015331:Cohort Studies; D003131:Combined Modality Therapy; D017147:Defibrillators, Implantable; D057210:Delayed Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010138:Pacemaker, Artificial; D012307:Risk Factors; D012720:Severity of Illness Index; D017678:Sex Distribution; D020521:Stroke / Q000453:epidemiology* / Q000503:physiopathology / Q000517:prevention & control*; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents