title: Predictors of cerebral microembolization during phased radiofrequency ablation of atrial fibrillation: role of the ongoing rhythm and the site of energy delivery.
abstract: BACKGROUND
  Pulmonary vein isolation with phased radiofrequency current and use of a pulmonary vein ablation catheter (PVAC) has recently been associated with a high incidence of clinically silent brain infarcts on diffusion-weighted magnetic resonance imaging, and a high microembolic signal (MES) count detected by transcranial Doppler. We investigated the potential effects of the ongoing rhythm and the target vein during energy delivery (ED) on MES generation during PVAC ablations.
  
  
  RESULTS
  A total of 735 EDs during 48 PVAC ablations were analyzed. MES counts were recorded for each ED and time-stamped for correlation with the ongoing rhythm and the target vein for each ED. Significantly higher MES counts were observed during ablations of the left-sided as compared with the right-sided pulmonary veins (P = 0.0003). Similarly, higher MES counts were detected during EDs in atrial fibrillation as compared with sinus rhythm when the temperature was >56°C (P < 0.0001). The ongoing rhythm had no effect on the number of MESs at lower temperatures during ablation.
  
  
  CONCLUSIONS
  Both the ongoing rhythm during ED and the site of ablation influence microembolus generation during PVAC ablation procedures.
authors.affiliation: Institute of Cardiology, University of Debrecen, Debrecen, Hungary.
authors.forename: Edina
authors.initials: E
authors.lastname: Nagy-Balo
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kiss
authors.forename: Catherine
authors.initials: C
authors.lastname: Condie
authors.forename: Mark
authors.initials: M
authors.lastname: Stewart
authors.forename: Istvan
authors.initials: I
authors.lastname: Edes
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Csanadi
mesh_terms: D001281:Atrial Fibrillation; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012189:Retrospective Studies
keywords: GENius generator; PVAC catheter; atrial fibrillation; pulmonary vein isolation