title: Imaging and Right Ventricular Pacing Lead Position: A Comparison of CT, MRI, and Echocardiography.
abstract: BACKGROUND
  Right ventricular nonapical (RVNA) pacing may reduce the risk of heart failure. Fluoroscopy is the standard approach to determine lead tip position, but is inaccurate. We compared cardiac computed tomography (CT), magnetic resonance imaging (MRI), two-dimensional and three-dimensional transthoracic echocardiography (TTE), and chest x-ray (CXR) to assess which provides the optimal assessment of right ventricular (RV) lead tip position.
  
  
  METHODS
  Eighteen patients with MRI-conditional pacemakers (10 RVNA and eight apical [RVA] leads) underwent contrast CT, MRI, TTE, and a standard postimplant posteroanterior and lateral CXR. To compare images, the RV was arbitrarily partitioned into three long-axis segments (right ventricular outflow tract, middle, and apex), and two short-axis segments (septal and nonseptal). Agreement between modalities was assessed.
  
  
  RESULTS
  RV lead tip position was identified in all patients on CT, TTE, and CXR, but was not identified in seven (39%) patients on MRI due to device-related artifact. Of 10 leads deemed to be nonapical/septal during implant, 70% were identified as nonapical on CXR, 60% on CT, 60% on MRI, and 80% on TTE. On CT imaging only 10% were truly septal, 20% on MRI, 30% on CXR, and 80% on TTE. Agreement was better between modalities when assessing position of the designated RVA leads.
  
  
  CONCLUSIONS
  During implant leads intended for the septum are not confirmed as such on subsequent imaging, and marked heterogeneity is apparent between modalities. MRI is limited by artifact, and discrepancy exists between TTE and CT in identifying septal lead position. CT gave the clearest definition of lead tip position.
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Moore
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Coucher
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Stanley
authors.initials: S
authors.lastname: Ngai
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.|School of Medicine, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Tony
authors.initials: T
authors.lastname: Stanton
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Sudhir
authors.initials: S
authors.lastname: Wahi
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.|School of Medicine, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Gould
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Cameron
authors.initials: C
authors.lastname: Booth
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.
authors.forename: Jit
authors.initials: J
authors.lastname: Pratap
authors.affiliation: Princess Alexandra Hospital, Brisbane, Queensland, Australia.|School of Medicine, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Gerald
authors.initials: G
authors.lastname: Kaye
mesh_terms: D004452:Echocardiography / Q000379:methods; D004567:Electrodes, Implanted; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D019919:Prosthesis Implantation / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: echocardiography; electrocardiogram; imaging; pacing