title: Non-inducibility post-pulmonary vein isolation achieving exit block predicts freedom from atrial fibrillation.
abstract: OBJECTIVE
  This study evaluates whether non-inducibility of atrial fibrillation (AF) after achieving bi-directional electrical pulmonary vein (PV) isolation is a useful predictor of freedom from AF recurrence.
  
  
  RESULTS
  This study included 102 consecutive patients who underwent PV isolation for symptomatic paroxysmal (59%), persistent (32%), or permanent (9%) AF. Patients were followed for 16+/-10 months. Complete isolation of all four PVs was confirmed by demonstration of bi-directional block, defined by both loss of PV potentials and failure to capture the LA by pacing (at 10 mA) 10-14 bipolar pairs of electrodes on a circumferential catheter positioned at the entrance of the PV. Induction of AF by burst pacing on/off isoproterenol was attempted after PV isolation. Freedom from recurrent symptomatic or asymptomatic AF was present in 70% of patients at 6 months and 62% of patients at 12 months. In multi-variable analysis, non-inducibility post-PV isolation (OR=3.84, P=0.047) and paroxysmal AF (OR=4.80, P=0.012) predicted freedom from AF at 12 months.
  
  
  CONCLUSIONS
  Non-inducibility of AF after bi-directional PV isolation predicts maintenance of sinus rhythm. This finding suggests that routine extensive left atrial ablation may be unnecessary.
authors.affiliation: Harvard-Thorndike Electrophysiology Institute, Cardiovascular Division, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Baker 4, Boston, MA 02215, USA.
authors.forename: Vidal
authors.initials: V
authors.lastname: Essebag
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Baldessin
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Reynolds
authors.forename: Seth
authors.initials: S
authors.lastname: McClennen
authors.forename: Jignesh
authors.initials: J
authors.lastname: Shah
authors.forename: Kevin F
authors.initials: KF
authors.lastname: Kwaku
authors.forename: Peter
authors.initials: P
authors.lastname: Zimetbaum
authors.forename: Mark E
authors.initials: ME
authors.lastname: Josephson
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D006327:Heart Block / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011667:Pulmonary Veins / Q000601:surgery*; D012307:Risk Factors