title: Clinical safety of the ProMRI pacemaker system in patients subjected to head and lower lumbar 1.5-T magnetic resonance imaging scanning conditions.
abstract: BACKGROUND
  Permanent cardiac pacemakers have historically been considered a contraindication to magnetic resonance imaging (MRI).
  
  
  OBJECTIVE
  The purpose of the ProMRI/ProMRI AFFIRM Study, which was a multicenter, prospective, single-arm, nonrandomized study, was to evaluate the clinical safety of the Biotronik ProMRI Pacemaker System under specific MRI conditions.
  
  
  METHODS
  The ProMRI Study (in the United States) and the ProMRI AFFIRM study (outside the United States) with identical design enrolled 272 patients with stable baseline pacing indices implanted with an Entovis or Evia pacemaker (DR-T or SR-T) and Setrox or Safio 53-cm or 60-cm lead. Device interrogation was performed at enrollment, pre-MRI and post-MRI scan, and 1 and 3 months post-MRI. End-points were (1) freedom from MRI- and pacing system-related serious adverse device effects (SADEs) through 1 month post-MRI, (2) freedom from atrial and ventricular MRI-induced pacing threshold increase (>0.5 V), and (3) freedom from P- and R-wave amplitude attenuation (<50%), or P wave <1.5 mV, or R wave <5.0 mV at 1 month post-MRI.
  
  
  RESULTS
  Two hundred twenty-six patients completed the MRI and 1-month post-MRI follow-up. No adverse events related to the implanted system and the MRI procedure occurred, resulting in an SADE-free rate of 100.0% (229/229, P <.001). Freedom from atrial and ventricular pacing threshold increase was 99.0% (189/191, P = .003) and 100% (217/217, P <.001), respectively. Freedom from P- and R- wave amplitude attenuation was 99.4% (167/168, P <.001) and 99.5% (193/194, P <.001), respectively.
  
  
  CONCLUSIONS
  The results of the ProMRI/ProMRI AFFIRM studies demonstrate the clinical safety and efficacy of the ProMRI pacemaker system in patients subjected to head and lower lumbar MRI conditions.
authors: Louisiana Heart Rhythm Specialists and Lafayette General Medical Center, Lafayette, Louisiana. Electronic address: wbailey@heartrhythmmd.com.
authors: William M
authors: WM
authors: Bailey
authors: University of Massachusetts Medical School, Amherst, Massachusetts.
authors: Lawrence
authors: L
authors: Rosenthal
authors: Private Practice, Cumberland, Maryland.
authors: Lameh
authors: L
authors: Fananapazir
authors: Washington University School of Medicine, St. Louis, Missouri.
authors: Marye
authors: M
authors: Gleva
authors: University of Iowa Hospitals and Clinics, Iowa City, Iowa.
authors: Alexander
authors: A
authors: Mazur
authors: St. Thomas, London, United Kingdom.
authors: C A
authors: CA
authors: Rinaldi
authors: Krankenhaus der Stadt Linz, Linz, Austria.
authors: Alexander
authors: A
authors: Kypta
authors: Semmelweis University Heart Center, Budapest, Hungary.
authors: Béla
authors: B
authors: Merkely
authors: Washington University School of Medicine, St. Louis, Missouri.
authors: Pamela K
authors: PK
authors: Woodard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006257:Head; D006801:Humans; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects; D011446:Prospective Studies
keywords: Bradycardia pacing; Clinical trial; Entovis; Evia; Magnetic resonance imaging; Pacemaker; ProMRI; Safety