title: Safety of serial MRI in patients with implantable cardioverter defibrillators.
abstract: OBJECTIVE
  While patients with cardiac implantable electronic devices could benefit from magnetic resonance (MR) imaging, the presence of such devices has been designated as an absolute contraindication to MR. Although scanning algorithms are proposed for cardiac implantable electronic devices, their safety remains uncertain. To address this issue, the safety of serial cardiac MR scans was evaluated in patients with implantable cardioverter defibrillators (ICDs).
  
  
  METHODS
  Three serial cardiac MR scans were prospectively performed at 1.5 T on 10 patients (9 men) of median age 56 years (range 51-68) with ICDs. ICD interrogation was performed before and after the MR scan and at a follow-up of median 370 days (range 274-723). Image quality was also assessed.
  
  
  RESULTS
  In all patients MR scanning occurred without complications. There were no differences between pre- and post-MR pacing capture threshold, pacing lead or high voltage lead impedance, or battery voltage values. During follow-up there were no occurrences of ICD dysfunction. Although most patients had image artifacts, the studies were generally diagnostic regarding left ventricular function and wall motion. Delayed enhancement imaging was of good quality for inferior wall and inferolateral infarcts, but ICD artifacts often affected the imaging of anterior wall infarcts.
  
  
  CONCLUSIONS
  Serial MR scans at 1.5 T in patients with ICDs, when carefully performed in a monitored setting, have no adverse effects on either patient or device. When required, single or multiple MR scans at 1.5 T may therefore be considered for clinical diagnostic purposes in these patients.
authors.affiliation: Division of Cardiology, Miller School of Medicine, University of Miami, Florida, USA.
authors.forename: M Juhani
authors.initials: MJ
authors.lastname: Junttila
authors.forename: Joel E
authors.initials: JE
authors.lastname: Fishman
authors.forename: Gustavo A
authors.initials: GA
authors.lastname: Lopera
authors.forename: Pradip M
authors.initials: PM
authors.lastname: Pattany
authors.forename: Darcy L
authors.initials: DL
authors.lastname: Velazquez
authors.forename: Adam R
authors.initials: AR
authors.lastname: Williams
authors.forename: Barry H
authors.initials: BH
authors.lastname: Trachtenberg
authors.forename: Cristina
authors.initials: C
authors.lastname: Sanina
authors.forename: Jacques
authors.initials: J
authors.lastname: Mather
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Hare
mesh_terms: D000368:Aged; D017147:Defibrillators, Implantable; D004869:Equipment Safety; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors