title: Bipolar electrograms characteristics at the left atrial-pulmonary vein junction: Toward a new algorithm for automated verification of pulmonary vein isolation.
abstract: BACKGROUND
  Verification of pulmonary vein isolation (PVI) is challenging because of the coexistence of PV and far-field potentials in bipolar electrograms recorded at the left atrial-pulmonary vein (LA-PV) junction.
  
  
  OBJECTIVE
  The purpose of this study was to characterize algorithmically LA-PV potentials before and after PVI and to develop an algorithm to differentiate nonisolated from isolated PVs.
  
  
  METHODS
  In 61 patients, we characterized-by type (morphology) and parameters-1440 electrograms recorded during sinus rhythm before and after PVI. Based on vein-dependent prevalence of a given type before and after PVI (first step) and based on vein- and type-dependent cutoff values in parameters specific for recordings before and after PVI (second step), we developed a 2-step algorithm to differentiate nonisolated from isolated PVs. We prospectively validated this algorithm in another dataset of 20 patients.
  
  
  RESULTS
  Characteristics before and after PVI were as follows: low voltage (10% ± 7% vs 36% ± 15%), monophasic (13% ± 4% vs 27% ± 9%), biphasic (18% ± 4% vs 21% ± 9%), triphasic (22% ± 5% vs 11% ± 13%), multiphasic (26% ± 7% vs 3% ± 3%), double potentials (11% ± 5% vs 2% ± 1%), peak-to-peak amplitude (0.97 ± 0.21 mV vs 0.35 ± 0.23 mV), maximal slope (0.179 ± 0.033 mV/ms vs 0.071 ± 0.029 mV/ms), minimal slope (0.030 ± 0.003 mV/ms vs 0.024 ± 0.002 mV/ms), and sharpest peak (1.82° ± 0.26° vs 3.45° ± 0.85°, P < .01 for all except biphasic). Overall sensitivity and specificity of the 2-step algorithm was 100% and 87%, respectively.
  
  
  CONCLUSIONS
  We algorithmically characterized LA-PV potentials before and after PVI in a large dataset (library of types and parameters). This library enabled us to develop an accurate 2-step algorithm to automatically differentiate nonisolated from isolated PVs. The 2-step algorithm is objective and reliable for assessing PV isolation without the need for pacing maneuvers.
authors.affiliation: Ghent University Hospital, Heart Center, Ghent, Belgium. Electronic address: milad.elhaddad@ugent.be.
authors.forename: Milad
authors.initials: M
authors.lastname: El Haddad
authors.affiliation: Applied Biomedical Systems, Maastricht, The Netherlands.
authors.forename: Richard
authors.initials: R
authors.lastname: Houben
authors.affiliation: Sint-Jan Hospital Bruges, Department of Cardiology, Bruges, Belgium.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Berte
authors.affiliation: Ghent University Hospital, Heart Center, Ghent, Belgium.
authors.forename: Frederic
authors.initials: F
authors.lastname: Van Heuverswyn
authors.affiliation: Ghent University Hospital, Heart Center, Ghent, Belgium.
authors.forename: Roland
authors.initials: R
authors.lastname: Stroobandt
authors.affiliation: Sint-Jan Hospital Bruges, Department of Cardiology, Bruges, Belgium.
authors.forename: Yves
authors.initials: Y
authors.lastname: Vandekerckhove
authors.affiliation: Sint-Jan Hospital Bruges, Department of Cardiology, Bruges, Belgium.
authors.forename: Rene
authors.initials: R
authors.lastname: Tavernier
authors.affiliation: Ghent University Hospital, Heart Center, Ghent, Belgium; Sint-Jan Hospital Bruges, Department of Cardiology, Bruges, Belgium.
authors.forename: Mattias
authors.initials: M
authors.lastname: Duytschaever
mesh_terms: D000368:Aged; D000465:Algorithms; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation; D015331:Cohort Studies; D004562:Electrocardiography; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Ablation; Algorithm; Atrial fibrillation ablation; Electrogram; Pulmonary vein isolation; Pulmonary vein potential