title: Electrophysiological mapping and histological examinations of the swine atrium with sustained (> or =24 h) atrial fibrillation: a suitable animal model for studying human atrial fibrillation.
abstract: OBJECTIVE
  Interventional elimination of chronic persistent atrial fibrillation (AFib) remains difficult. An animal model mimicking the clinical situation is important.
  
  
  RESULTS
  Twenty-five adult pigs were implanted with a high-speed atrial pacemaker. After continuous pacing at 600 bpm for 6 weeks, 20 (91%) of the 22 survivals developed sustained AFib lasting for at least 24 h. Epicardial dense mapping revealed multiple coexisting reentrant wavelets in the left and the right atrium (LA and RA, respectively; 10.6 +/- 2.9 vs. 7.6 +/- 2.4 wavelets/cm(2)/s; p < 0.002). The mean local A-A intervals were 87.2 +/- 14.6 ms in the LA and 103.3 +/- 19.0 ms in the RA (p < 0.0002). Acute termination of sustained AFib was successful in 3 of the 5 pigs by propafenone, but in none of the 6 by dl-sotalol. Epicardial cryothermal ablation failed to terminate any AFib by compartmentalization of the RA free wall alone (4 pigs) or together with the LA appendage (4 pigs). Electron microscopic examination demonstrated diffuse perinuclear myolysis, myofibrillar fragmentation and mitochondrial crystal disruption in the atrium.
  
  
  CONCLUSIONS
  Pacing-induced sustained AFib (> or =24 h) in adult pigs is a feasible and efficient animal model with electrophysiological and histological characteristics closely similar to those seen in humans.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC. jiunn@ha.mc.ntu.edu.tw
authors.forename: Jiunn-Lee
authors.initials: JL
authors.lastname: Lin
authors.forename: Ling-Ping
authors.initials: LP
authors.lastname: Lai
authors.forename: Chih-Shen
authors.initials: CS
authors.lastname: Lin
authors.forename: Chao-Cheng
authors.initials: CC
authors.lastname: Du
authors.forename: Tsu-Juey
authors.initials: TJ
authors.lastname: Wu
authors.forename: Shih-Ping
authors.initials: SP
authors.lastname: Chen
authors.forename: Wen-Chuan
authors.initials: WC
authors.lastname: Lee
authors.forename: Ping-Cheng
authors.initials: PC
authors.lastname: Yang
authors.forename: Yung-Zu
authors.initials: YZ
authors.lastname: Tseng
authors.forename: Wen-Pin
authors.initials: WP
authors.lastname: Lien
authors.forename: Shoei K Stephen
authors.initials: SK
authors.lastname: Huang
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D018780:Body Surface Potential Mapping; D002304:Cardiac Pacing, Artificial; D003452:Cryosurgery; D004195:Disease Models, Animal; D004452:Echocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D008854:Microscopy, Electron; D008955:Models, Cardiovascular; D032383:Myocytes, Cardiac / Q000473:pathology; D010138:Pacemaker, Artificial; D011405:Propafenone / Q000627:therapeutic use; D013318:Stroke Volume / Q000502:physiology; D016019:Survival Analysis; D013552:Swine; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; D011405:Propafenone