title: Pacing lead implantation without live fluoroscopy: feasibility of acute success in the live canine model.
abstract: BACKGROUND
  Fluoroscopic visualization for transvenous pacing lead placement necessitates lead shielding to minimize radiation exposure. An electromagnetic (EM) navigation system that integrates real-time intracardiac tracking within an anatomic navigation environment may provide an effective alternative for lead delivery that obviates live fluoroscopy. We assessed feasibility of pacing lead implantation with electromagnetic tracking guided solely by radiographic virtual navigation and compared this to fluoroscopy-guided implants in a canine model.
  
  
  METHODS
  Seven mongrel dogs with normal hearts were randomized to 47 pacing lead placements in the right atrium (RA) or right ventricle (RV) guided by single-plane fluoroscopy, or an experimental EM navigation system guided by registered fluoroscopic snapshots obtained before implant (EMN). Ability to achieve successful lead delivery acutely was assessed, and pacing parameters as well as fluoroscopy and implant times were measured. Means were compared using a paired t-test.
  
  
  RESULTS
  All lead delivery attempts were acutely successful. One atrial lead dislodged with EMN, resulting in 46 successful pacing attempts. There was no statistical difference in pacing parameters and time for lead placement between the approaches (EMN vs fluoroscopic navigation [mean +/- SD]: RA threshold 1.15 V +/- 0.98 V vs 1.95 V +/- 0.98 V [P = NS], RV threshold 1.18 V +/- 0.58 V vs 1.42 V +/- 0.63 V [P = NS], implant time 4:38 +/- 2:37 minutes vs 4:44 +/- 2:38 minutes [P = NS]). No live fluoroscopy was required for EMN implants.
  
  
  CONCLUSIONS
  Pacing lead placement with an EM system guided by preprocedural fluoroscopic views is feasible and comparable to fluoroscopic navigation, and avoids the use of live fluoroscopy.
authors.affiliation: Electrophysiology Laboratories of Aurora Sinai/Aurora St Luke's Medical Centers, University of Wisconsin School of Medicine, Milwaukee, Wisconsin, USA.
authors.forename: Indrajit
authors.initials: I
authors.lastname: Choudhuri
authors.forename: David
authors.initials: D
authors.lastname: Krum
authors.forename: John
authors.initials: J
authors.lastname: Hare
authors.forename: Jim
authors.initials: J
authors.lastname: Kelley
authors.forename: David
authors.initials: D
authors.lastname: Becker
authors.forename: M Eyman
authors.initials: ME
authors.lastname: Mortada
authors.forename: Masood
authors.initials: M
authors.lastname: Akhtar
authors.forename: Jasbir
authors.initials: J
authors.lastname: Sra
mesh_terms: D000818:Animals; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004285:Dogs; D005240:Feasibility Studies; D005471:Fluoroscopy; D023421:Models, Animal; D010138:Pacemaker, Artificial; D019919:Prosthesis Implantation / Q000379:methods*; D013997:Time Factors