title: Relation between projection positions and X-ray radiation doses during placement of the coronary sinus mapping electrode.
abstract: OBJECTIVE
  To reduce X-ray radiation injury, we investigated the relation between projection positions and X-ray radiation doses when a coronary sinus mapping electrode was placed.
  
  
  METHODS
  There were 400 patients in whom a coronary sinus mapping electrode was placed for intracardiac electrophysiologic examination or radio-frequency catheter ablation in our hospital between 1 June 2008 and 31 May 2011. The doctors who placed the coronary sinus mapping electrode and the projection positions including posteroanterior, left anterior oblique 45°, and right anterior oblique 30° projection positions were randomly selected. X-ray doses were recorded when the coronary sinus mapping electrode was placed, and then, these were compared between the three projection positions.
  
  
  RESULTS
  The X-ray dose was significantly lower in the right anterior oblique 30° projection position (50.01 ± 11.38 mGy) than in the posteroanterior projection position (68.05 ± 18.85 mGy, q = 12.924, p = 0.000) and the left anterior oblique 45° projection position (71.66 ± 16.95 mGy, q = 15.214, p = 0.000). There were no statistical significances in X-ray doses between the posteroanterior and the left anterior oblique 45° projection positions (p = 0.066) and different operators (p = 0.985).
  
  
  CONCLUSIONS
  Based on the results of this study, we suggest that in placing the coronary sinus mapping electrode, the right anterior oblique 30° projection position should be first adopted because it can allow the electrode to be easily placed and reduce the X-ray radiation dose as much as possible.
authors.affiliation: Cardiovascular Medical Department, The First People's Hospital of Nantong, Nantong 226001, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Lin
authors.forename: Jian-Fei
authors.initials: JF
authors.lastname: Huang
authors.forename: Hui-He
authors.initials: HH
authors.lastname: Lu
authors.forename: Lin-Sheng
authors.initials: LS
authors.lastname: Shi
authors.forename: Jue
authors.initials: J
authors.lastname: Wang
authors.forename: Shu-Qing
authors.initials: SQ
authors.lastname: Zhang
mesh_terms: D000704:Analysis of Variance; D017115:Catheter Ablation; D054326:Coronary Sinus / Q000000981:diagnostic imaging* / Q000601:surgery*; D004566:Electrodes; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000517:prevention & control*; D015641:Radiography, Interventional / Q000009:adverse effects / Q000379:methods*; D014965:X-Rays