title: Reducing Radiation Exposure During CRT Implant Procedures: Single-Center Experience With Low-Dose Fluoroscopy Settings and a Sensor-Based Navigation System (MediGuide).
abstract: BACKGROUND
  Cardiac resynchronization therapy (CRT) implant procedures are often complex and prolonged, resulting in substantial ionizing radiation (IR) exposure to the patient and operator. We assessed the impact of lower-dose fluoroscopy settings and a sensor-based electromagnetic tracking system (MediGuide™, MDG) on reducing IR exposure during CRT implantation.
  
  
  METHODS
  A single-center 2-group cohort study was conducted on 348 consecutive patients, age 66.4 ± 11.0 years, 80.4% male, with CRT implant procedures from 2013 to 2015. Patients were arbitrarily assigned to MDG (N = 239) versus no MDG (N = 109) guidance. Lower-dose fluoroscopy settings were adopted in January 2015 (3 instead of 6 fps; 23 instead of 40 nGy/pulse; N = 101).
  
  
  RESULTS
  Overall, MDG was associated with an 82.1% reduction in IR exposure (393 μGray·m2vs. 2191 μGray·m2, P < 0.001). Lower-dose fluoroscopy resulted in a 59.5% reduction in IR-exposure without MDG (1055 μGray·m2vs. 2608 μGray·m2, P < 0.001) and 81.8% reduction with MDG (108 μGray·m2vs. 595 μGray·m2, P < 0.001). Low-dose fluoroscopy combined with MDG was associated with a 95.9% lower exposure to IR when compared to standard fluoroscopy without MDG (108 μGray·m2vs. 2608 μGray·m2, P < 0.001). Procedures with MDG were shorter (96 minutes vs. 123 minutes, P < 0.001) and associated with a trend towards a higher success rate (94.6% vs. 89.0%, P = 0.062), with fewer coronary sinus cannulation failures (2.1% vs. 6.4%, P = 0.040).
  
  
  CONCLUSIONS
  Low-dose fluoroscopy settings are highly effective (>50%) in reducing IR exposure during CRT implant procedures. When combined with MDG, >95% reduction in IR exposure is achieved. Moreover, MDG shortens procedural duration and may improve acute procedural outcomes.
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Bernard
authors.initials: B
authors.lastname: Thibault
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Blandine
authors.initials: B
authors.lastname: Mondésert
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Laurent
authors.initials: L
authors.lastname: Macle
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Dubuc
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Katia
authors.initials: K
authors.lastname: Dyrda
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Mario
authors.initials: M
authors.lastname: Talajic
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Denis
authors.initials: D
authors.lastname: Roy
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Léna
authors.initials: L
authors.lastname: Rivard
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Guerra
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Jason G
authors.initials: JG
authors.lastname: Andrade
authors.affiliation: Electrophysiology Service, Montreal Heart Institute and the Department of Medicine, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Paul
authors.initials: P
authors.lastname: Khairy
keywords: cardiac resynchronization therapy; cardiovascular imaging; implantation; radiation dosing; radiation risk