title: Changes in P-wave morphology after pulmonary vein isolation: insights from computer simulations.
abstract: OBJECTIVE
  Apparently conflicting clinical measurements of P-wave duration (PWD) pre- vs. post-ablation have been reported. To assist the interpretation of these clinical data, we used a computer model of the atria and torso to simulate P waves before and after pulmonary vein (PV) isolation.
  
  
  RESULTS
  Twenty ablation patterns were designed (segmental or ipsilateral ablation; five distances to PV sleeves; addition of a roof line or not). Possible PV reconnections were introduced as gaps in the ablation lines. PWD and area were measured during sinus rhythm in vectorcardiogram (VCG) magnitude signals and on the 16-lead ECG before and after ablation, and after PV reconnection. After PV isolation, biatrial activation time was prolonged by 0-5 ms without and by 48±5 ms with roof line. Yet PWD was shortened in lead V3 and V4 by up to 15 ms. The effect of ablation on P-wave morphology was stronger when larger PV areas were isolated. Segmental and ipsilateral PV isolation led to concordant results. P-wave area increased in V1 and decreased in V6. Changes in PWD and area on the VCG were sensitive to the threshold used for detecting the end of the P wave. The occurrence of PV reconnection was best identified on leads V3, V4, and V9.
  
  
  CONCLUSIONS
  PV isolation and reconnection induced measurable changes on the 16-lead ECG that might be used to improve patient follow-up after ablation.
authors.affiliation: Département de Physiologie Moléculaire et Intégrative, Institut de Génie Biomédical, Université de Montréal, Montréal, QC, Canada.|Centre de Recherche, Hôpital du Sacré-Cœur de Montréal, 5400 boul. Gouin Ouest, Montréal, QC H4J 1C5, Canada.
authors.forename: Mirabeau
authors.initials: M
authors.lastname: Saha
authors.affiliation: Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland.
authors.forename: Giulio
authors.initials: G
authors.lastname: Conte
authors.affiliation: Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland.
authors.forename: Maria Luce
authors.initials: ML
authors.lastname: Caputo
authors.affiliation: Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland.
authors.forename: François
authors.initials: F
authors.lastname: Regoli
authors.affiliation: Institute of Computational Science, Center for Computational Medicine in Cardiology, Università della Svizzera Italiana, Lugano, Switzerland.
authors.forename: Rolf
authors.initials: R
authors.lastname: Krause
authors.affiliation: Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland.|Institute of Computational Science, Center for Computational Medicine in Cardiology, Università della Svizzera Italiana, Lugano, Switzerland.
authors.forename: Angelo
authors.initials: A
authors.lastname: Auricchio
authors.affiliation: Département de Physiologie Moléculaire et Intégrative, Institut de Génie Biomédical, Université de Montréal, Montréal, QC, Canada vincent.jacquemet@umontreal.ca.|Centre de Recherche, Hôpital du Sacré-Cœur de Montréal, 5400 boul. Gouin Ouest, Montréal, QC H4J 1C5, Canada.
authors.forename: Vincent
authors.initials: V
authors.lastname: Jacquemet
mesh_terms: D000200:Action Potentials; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D004562:Electrocardiography; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D007700:Kinetics; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D066230:Patient-Specific Modeling; D011237:Predictive Value of Tests; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D060726:Torso / Q000033:anatomy & histology; D016896:Treatment Outcome
keywords: Activation map ; Atrial fibrillation ; Catheter ablation ; Computer modelling ; P-wave morphology; Pulmonary vein reconnection 