title: Radiofrequency catheter ablation of atrioventricular nodal reentrant tachycardia guided by magnetic navigation system: a prospective randomized comparison with conventional procedure.
abstract: BACKGROUND
  Atrioventricular nodal reentrant tachycardia (AVNRT) is one of the most common paroxysmal supraventricular tachyarrhythmias. The aim of the study was to prospectively compare the characteristics of radiofrequency catheter ablation of AVNRT guided by a magnetic navigation system with the conventional procedure.
  
  
  METHODS
  Patients with AVNRT diagnosed by electrophysiological tests were randomized into two groups. In the conventional technique group (CMT), a common 4-mm-tip quadrapolar temperature-controlled ablation catheter was used. In the magnetic navigation system guidance group (MNS), a magnetic 4-mm-tip quadrapolar temperature-controlled ablation catheter was used. The following parameters were collected and compared between the two groups: ablation procedure time, patient fluoroscopy time, operator fluoroscopy time, energy delivery numbers, maximal energy per deployment, success rate, complication rate and operative cost.
  
  
  RESULTS
  Forty patients were enrolled and randomized into CMT and MNS groups. The age, gender, tachycardia history and basic cardiovascular diseases of the two groups were comparable (P > 0.05). All procedures were conducted successfully without complications. No tachycardia recurred during the follow-up period of (9.3 ± 2.6) months. In the MNS group, the patient and operator fluoroscopy times ((11.5 ± 4.3) min, (4.2 ± 1.5) min), energy delivery numbers (3.2 ± 0.9), and maximal energy per deployment ((16.9 ± 3.4) W) were shorter or lower than those of the CMT group ((14.3 ± 6.2) min, (13.6 ± 3.5) min, 6.3 ± 2.1, (23.7 ± 1.3) W, respectively) (P < 0.05). But the operative cost for the MNS group was higher than that of the CMT group (P < 0.01).
  
  
  CONCLUSIONS
  Magnetic navigation system guided radiofrequency catheter ablation of AVNRT has the advantages of shorter fluoroscopy time and lower energy delivery numbers and maximal energy per deployment compared to the present conventional ablation technique.
authors.affiliation: Institute of Geriatric Cardiology, Chinese People's Liberation Army General Hospital, Beijing 100853, China.
authors.forename: Yu-Xiao
authors.initials: YX
authors.lastname: Zhang
authors.forename: Cai-Yi
authors.initials: CY
authors.lastname: Lu
authors.forename: Qiao
authors.initials: Q
authors.lastname: Xue
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Yan
authors.forename: Sheng-Hua
authors.initials: SH
authors.lastname: Zhou
mesh_terms: D017115:Catheter Ablation / Q000379:methods*; D006801:Humans; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000601:surgery*; D016896:Treatment Outcome