title: Feasibility of extended ambulatory electrocardiogram monitoring to identify silent atrial fibrillation in high-risk patients: the Screening Study for Undiagnosed Atrial Fibrillation (STUDY-AF).
abstract: BACKGROUND
  Identification of silent atrial fibrillation (AF) could prevent stroke and other sequelae.
  
  
  OBJECTIVE
  Screening for AF using continuous ambulatory electrocardiographic (ECG) monitoring can detect silent AF in asymptomatic in patients with known risk factors.
  
  
  METHODS
  We performed a single-center prospective screening study using a wearable patch-based device that provides up to 2 weeks of continuous ambulatory ECG monitoring (iRhythm Technologies, Inc.). Inclusion criteria were age ≥55 years and ≥2 of the following risk factors: coronary disease, heart failure, hypertension, diabetes, sleep apnea. We excluded patients with prior AF, stroke, transient ischemic attack, implantable pacemaker or defibrillator, or with palpitations or syncope in the prior year.
  
  
  RESULTS
  Out of 75 subjects (all male, age 69 ± 8.0 years; ejection fraction 57% ± 8.7%), AF was detected in 4 subjects (5.3%; AF burden 28% ± 48%). Atrial tachycardia (AT) was present in 67% (≥4 beats), 44% (≥8 beats), and 6.7% (≥60 seconds) of subjects. The combined diagnostic yield of sustained AT/AF was 11%. In subjects without sustained AT/AF, 11 (16%) had ≥30 supraventricular ectopic complexes per hour.
  
  
  CONCLUSIONS
  Outpatient extended ECG screening for asymptomatic AF is feasible, with AF identified in 1 in 20 subjects and sustained AT/AF identified in 1 in 9 subjects, respectively. We also found a high prevalence of asymptomatic AT and frequent supraventricular ectopic complexes, which may be relevant to development of AF or stroke. If confirmed in a larger study, primary screening for AF could have a significant impact on public health.
authors: Department of Cardiology, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.|Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.
authors: Mintu P
authors: MP
authors: Turakhia
authors: Department of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.
authors: Aditya J
authors: AJ
authors: Ullal
authors: Department of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.
authors: Donald D
authors: DD
authors: Hoang
authors: Department of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.
authors: Claire T
authors: CT
authors: Than
authors: Department of Medicine, Division of Cardiology, Johns Hopkins School of Medicine, Baltimore, Maryland.
authors: Jared D
authors: JD
authors: Miller
authors: Department of Cardiology, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.|Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.
authors: Karen J
authors: KJ
authors: Friday
authors: Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.
authors: Marco V
authors: MV
authors: Perez
authors: Department of Cardiology, Yale University School of Medicine, New Haven, Connecticut.
authors: James V
authors: JV
authors: Freeman
authors: Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.
authors: Paul J
authors: PJ
authors: Wang
authors: Department of Cardiology, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.|Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.
authors: Paul A
authors: PA
authors: Heidenreich
mesh_terms: D000368:Aged; D058070:Asymptomatic Diseases; D001281:Atrial Fibrillation / Q000175:diagnosis*; D015716:Electrocardiography, Ambulatory / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D010045:Outpatients; D011446:Prospective Studies; D020521:Stroke / Q000517:prevention & control