title: Abnormal atrial activation in young patients with lone atrial fibrillation.
abstract: OBJECTIVE
  Patients with a history of atrial fibrillation (AF) have previously been shown to have altered atrial conduction, as seen non-invasively using signal-averaged P-wave analysis. However, little is known about the P-wave morphology in patients in the early phases of AF with structurally normal hearts.
  
  
  RESULTS
  Thirty-six patients with lone AF were included before the age of 40 years (34±4 years, 34 men) and compared with age- and gender-matched control subjects. Standard 12-lead electrocardiogram (ECG) was recorded for at least 10 s. P-wave morphology and duration were estimated using signal-averaged P-wave analysis. Echocardiography was performed in association with the ECG recording. Heart rate (67±13 vs. 65±7 b.p.m., P=0.800) and PQ-interval (163±16 vs. 164±23 ms, P=0.629) were similar in AF cases and controls, as was P-wave duration (136±13 vs. 129±13 ms, P=0.107). The distribution of P-wave morphology differed between the AF cases and controls [33/58/0/8 vs. 75/25/0/0% (Type 1/Type 2/Type 3/atypical), P=0.001], with a larger proportion of patients with AF exhibiting signs of impaired interatrial conduction.
  
  
  CONCLUSIONS
  A significant difference in P-wave morphology distribution was seen between patients with early-onset, lone paroxysmal AF and age- and gender-matched healthy control subjects. This finding indicates that alterations in atrial electrophysiology are common in the early stage of the arrhythmia, and since it occurs in young patients without co-morbidity may well be the cause rather than the consequence of AF.
authors.affiliation: Department of Cardiology, Lund University, SE-221 85 Lund, Sweden. fredrik.holmqvist@med.lu.se
authors.forename: Fredrik
authors.initials: F
authors.lastname: Holmqvist
authors.forename: Morten S
authors.initials: MS
authors.lastname: Olesen
authors.forename: Arnljot
authors.initials: A
authors.lastname: Tveit
authors.forename: Steve
authors.initials: S
authors.lastname: Enger
authors.forename: Jari
authors.initials: J
authors.lastname: Tapanainen
authors.forename: Raija
authors.initials: R
authors.lastname: Jurkko
authors.forename: Rasmus
authors.initials: R
authors.lastname: Havmöller
authors.forename: Stig
authors.initials: S
authors.lastname: Haunsø
authors.forename: Jonas
authors.initials: J
authors.lastname: Carlson
authors.forename: Jesper H
authors.initials: JH
authors.lastname: Svendsen
authors.forename: Pyotr G
authors.initials: PG
authors.lastname: Platonov
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000503:physiopathology*; D001783:Blood Flow Velocity / Q000502:physiology; D016022:Case-Control Studies; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male