title: Electromagnetic interference with implantable cardioverter-defibrillators at power frequency: an in vivo study.
abstract: BACKGROUND
  The number of implantable cardioverter-defibrillators (ICDs) for the prevention of sudden cardiac death is continuing to increase. Given the technological complexity of ICDs, it is of critical importance to identify and control possible harmful electromagnetic interferences between various sources of electromagnetic fields and ICDs in daily life and occupational environments.
  
  
  RESULTS
  Interference thresholds of 110 ICD patients (1-, 2-, and 3-chamber ICDs) were evaluated in a specifically developed test site. Patients were exposed to single and combined electric and magnetic 50-Hz fields with strengths of up to 30 kV·m⁻¹ and 2.55 mT. Tests were conducted considering worst-case conditions, including maximum sensitivity of the device or full inspiration. With devices being programmed to nominal sensitivity, ICDs remained unaffected in 91 patients (83%). Five of 110 devices (5%) showed transient loss of accurate right ventricular sensing, whereas 14 of 31 (45%) of the 2- and 3-chamber devices displayed impaired right atrial sensing. No interference was detected in 71 patients (65%) within the tested limits with programming to maximum sensitivity, whereas 20 of 110 subjects (18%) exhibited right ventricular disturbances and 19 of 31 (61%) subjects exhibited right atrial disturbances.
  
  
  CONCLUSIONS
  Extremely low-frequency daily-life electromagnetic fields do not disturb sensing capabilities of ICDs. However, strong 50-Hz electromagnetic fields, present in certain occupational environments, may cause inappropriate sensing, potentially leading to false detection of atrial/ventricular arrhythmic events. When the right atrial/right ventricular interferences are compared, the atrial lead is more susceptible to electromagnetic fields.
  
  
  BACKGROUND
  http://clinicaltrials.gov/ct2/show/NCT01626261. Unique identifier: NCT01626261.
authors.affiliation: Department of Internal Medicine I (Cardiology, Pneumology, Angiology) (A.N., C.K., M.Z., B.B., N.M., P.S.) and Research Center for Bioelectromagnetic Interaction at the Institute of Occupational Medicine; former at the Institute of Hygiene and Environmental Medicine (S.J., D.S., J.S.), University Hospital RWTH Aachen, Aachen, Germany; and Department of Cardiology, Maastricht University Medical Center, Maastricht, The Netherlands (C.K.).
authors.forename: Andreas
authors.initials: A
authors.lastname: Napp
authors.forename: Stephan
authors.initials: S
authors.lastname: Joosten
authors.forename: Dominik
authors.initials: D
authors.lastname: Stunder
authors.forename: Christian
authors.initials: C
authors.lastname: Knackstedt
authors.forename: Matthias
authors.initials: M
authors.lastname: Zink
authors.forename: Barbara
authors.initials: B
authors.lastname: Bellmann
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Marx
authors.forename: Patrick
authors.initials: P
authors.lastname: Schauerte
authors.forename: Jiri
authors.initials: J
authors.lastname: Silny
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000628:therapy*; D016757:Death, Sudden, Cardiac / Q000517:prevention & control; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004574:Electromagnetic Fields / Q000009:adverse effects*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D012189:Retrospective Studies; D018570:Risk Assessment
keywords: defibrillators, implantable; electromagnetic fields; power sources; threshold limit values