Electrical Remodeling of the Atrium in an Anatomic Model of Atrial Flutter

• Joseph B. Morton

  From the Royal Melbourne Hospital (J.B.M., J.M.K.), Department of Cardiology, Melbourne, Australia; Department of Medicine (M.J.B., J.M.P., J.B.M., J.M.K.), The University of Melbourne, Melbourne, Australia; and Department of Cardiac Surgery (J.R.), Austin and Repatriation Medical Centre, Melbourne, Australia.

• Melissa J. Byrne

  From the Royal Melbourne Hospital (J.B.M., J.M.K.), Department of Cardiology, Melbourne, Australia; Department of Medicine (M.J.B., J.M.P., J.B.M., J.M.K.), The University of Melbourne, Melbourne, Australia; and Department of Cardiac Surgery (J.R.), Austin and Repatriation Medical Centre, Melbourne, Australia.

• John M. Power

  From the Royal Melbourne Hospital (J.B.M., J.M.K.), Department of Cardiology, Melbourne, Australia; Department of Medicine (M.J.B., J.M.P., J.B.M., J.M.K.), The University of Melbourne, Melbourne, Australia; and Department of Cardiac Surgery (J.R.), Austin and Repatriation Medical Centre, Melbourne, Australia.

• Jai Raman

  From the Royal Melbourne Hospital (J.B.M., J.M.K.), Department of Cardiology, Melbourne, Australia; Department of Medicine (M.J.B., J.M.P., J.B.M., J.M.K.), The University of Melbourne, Melbourne, Australia; and Department of Cardiac Surgery (J.R.), Austin and Repatriation Medical Centre, Melbourne, Australia.

• Jonathan M. Kalman

  From the Royal Melbourne Hospital (J.B.M., J.M.K.), Department of Cardiology, Melbourne, Australia; Department of Medicine (M.J.B., J.M.P., J.B.M., J.M.K.), The University of Melbourne, Melbourne, Australia; and Department of Cardiac Surgery (J.R.), Austin and Repatriation Medical Centre, Melbourne, Australia.

書誌事項

タイトル別名

• Relationship Between Substrate and Triggers for Conversion to Atrial Fibrillation

抄録

Background — Atrial flutter (AFL) and atrial fibrillation (AF) frequently coexist, yet the specific relationship between these arrhythmias, and particularly whether sustained AFL leads to AF, is unknown. Methods and Results — We investigated the electrophysiological consequences of chronic AFL using an ovine anatomic right atrial Y-lesion model. AFL was induced in 7 animals, and 4 remained in sinus rhythm (controls). Sheep were monitored for spontaneous conversion of AFL to AF. Six of 7 sheep sustained AFL for 28 days. In 1 of 7 sheep, spontaneous conversion of AFL to AF occurred on day 5. AFL produced a highly significant fall in right and left atrial refractoriness (AERP, P <0.001), with 74±10% of the reduction occurring by day 3. Right atrial conduction velocity also fell significantly (baseline 89±9 cm/s versus day 28 64±14 cm/s, P <0.001) but over a slower time course. AERP and conduction velocity changes coincided with a characteristic biphasic decrease and increase in the AFL cycle length. The excitable gap (percent of AFL cycle length) increased from 13±3% at baseline to 46±8% by day 28 ( P <0.001). Sustained AF (>30 seconds) was not inducible at baseline but after 28 days of AFL could be induced in 6 of 6 sheep by critically timed single or multiple extrastimuli delivered either in sinus rhythm or AFL. There was no significant change in any parameter in control sheep. Conclusions — In this model, AFL produced electrical remodeling and the substrate for sustained AF. However, spontaneous conversion to AF was uncommon, and the development of AF was dependent on specific triggers.

収録刊行物

• Circulation

  Circulation 105 (2), 258-264, 2002-01-15

  Ovid Technologies (Wolters Kluwer Health)

キーワード

• Physiology (medical)
• Cardiology and Cardiovascular Medicine

詳細情報

• CRID: 1362825894222566016
• NII論文ID: 30022666871
• DOI: 10.1161/hc0202.102012
• ISSN: 15244539
• ISSN: 00097322
• Web Site: https://www.ahajournals.org/doi/full/10.1161/hc0202.102012
• データソース種別:
  • Crossref
  • CiNii Articles