title: Time-domain and morphological analysis of the P wave. Part II: effects of atrial pacing on P-wave features.
abstract: BACKGROUND
  The aim of this study was to compare time-domain and morphological descriptors of paced and spontaneous P wave in patients prone to atrial fibrillation (AF).
  
  
  METHODS
  Nineteen patients (nine women, aged 72 +/- 10 years) affected by paroxysmal AF and implanted with dual-chamber pacemakers (PM) were studied. Two 5-minute recordings were performed during spontaneous and paced rhythm. Electrocardiogram (ECG) signals were acquired using a 32-lead mapping system. Patients were grouped into two classes: no previous AF and previous AF groups, according to the number of AF episodes in the 6 months before the analysis.
  
  
  CONCLUSIONS
  During atrial pacing P wave appeared prolonged and morphologically more complex with respect to sinus rhythm. We also found that in patients at lower risk for AF, the atrial pacing changes the atrial activation to a greater extent than in patients at higher risk for AF. Finally, all time-domain and morphological descriptors of the P wave except one succeed in discriminating "no previous AF" and "previous AF" patients in spontaneous rhythm, while no significant differences have been observed during pacing for any parameters.
authors.affiliation: Department of Technologies and Health, Istituto Superiore di Sanità, Rome, Italy. federica.censi@iss.it
authors.forename: Frederica
authors.initials: F
authors.lastname: Censi
authors.forename: Chiara
authors.initials: C
authors.lastname: Ricci
authors.forename: Giovanni
authors.initials: G
authors.lastname: Calcagnini
authors.forename: Michele
authors.initials: M
authors.lastname: Triventi
authors.forename: Renato P
authors.initials: RP
authors.lastname: Ricci
authors.forename: Massimo
authors.initials: M
authors.lastname: Santini
authors.forename: Andrea
authors.initials: A
authors.lastname: Grammatico
authors.forename: Pietro
authors.initials: P
authors.lastname: Bartolini
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000517:prevention & control*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D013813:Therapy, Computer-Assisted / Q000379:methods*