© 2000 by European Society of Cardiology
Copyright © 2000, European Society of Cardiology
Dynamics of wavelets and their role in atrial fibrillation in the isolated sheep heart
aDepartment of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, USA
bDepartment of Pediatrics (Cardiology), SUNY Upstate Medical University, Syracuse, NY, USA
cUniversity of London, London, Ontario Department of Medicine (Cardiology), London, Canada
dDepartment of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
* Corresponding author. Tel.: +1-315-464-7949; fax: +1-315-464-8000 jalifej{at}upstate.edu
Background: The multiple wavelet hypothesis is the most commonly accepted mechanism underlying atrial fibrillation (AF). However, high frequency periodic activity has recently been suggested to underlie atrial fibrillation in the isolated sheep heart. We hypothesized that in this model, multiple wavelets during AF are generated by fibrillatory conduction away from periodic sources and by themselves may not be essential for AF maintenance. Methods and results: We have used a new method of phase mapping that enables identification of phase singularities (PSs), which flank individual wavelets during sustained AF. The approach enabled characterization of the initiation, termination, and lifespan of wavelets formed as a result of wavebreaks, which are created by the interaction of wave fronts with functional and anatomical obstacles in their path. AF was induced in six Langendorff-perfused sheep hearts in the presence of acetylcholine. High resolution video imaging was utilized in the presence of a voltage sensitive dye; two-dimensional phase maps were constructed from optical recordings. The major results were as follows: (1) the critical inter-PS/wavelet distance for the formation of rotors was 4 mm, (2) the spatial distribution of wavelets/PSs was non-random. (3) the lifespan of PSs/wavelets was short; 98% of PSs/wavelets existed for <1 rotation, and (4) the mean number of waves that entered our mapping field (15.7±1.6) exceeded the mean number of waves that exited it (9.7±1.5; P<0.001). Conclusions: Our results strongly suggest that multiple wavelets may result from breakup of high frequency organized waves in the isolated Langendorff-perfused sheep heart, and as such are not a robust mechanism for the maintenance of AF in our model.
KEYWORDS Acetylcholine; Arrhythmia (mechanisms); Mapping; Conduction (block); Supraventr. arrhythmias
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  K. Lemola, D. Chartier, Y.-H. Yeh, M. Dubuc, R. Cartier, A. Armour, M. Ting, M. Sakabe, A. Shiroshita-Takeshita, P. Comtois, et al. Pulmonary Vein Region Ablation in Experimental Vagal Atrial Fibrillation: Role of Pulmonary Veins Versus Autonomic Ganglia Circulation, January 29, 2008; 117(4): 470 - 477. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. R Kuo and N. A Trayanova Action potential morphology heterogeneity in the atrium and its effect on atrial reentry: a two-dimensional and quasi-three-dimensional study Phil Trans R Soc A, June 15, 2006; 364(1843): 1349 - 1366. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Zou, J. Kneller, L. J. Leon, and S. Nattel Substrate size as a determinant of fibrillatory activity maintenance in a mathematical model of canine atrium Am J Physiol Heart Circ Physiol, September 1, 2005; 289(3): H1002 - H1012. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Kneller*, J. Kalifa*, R. Zou, A. V. Zaitsev, M. Warren, O. Berenfeld, E. J. Vigmond, L. J. Leon, S. Nattel, and J. Jalife Mechanisms of Atrial Fibrillation Termination by Pure Sodium Channel Blockade in an Ionically-Realistic Mathematical Model Circ. Res., March 18, 2005; 96(5): e35 - e47. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. R de Groot and R. Coronel Acute ischemia-induced gap junctional uncoupling and arrhythmogenesis Cardiovasc Res, May 1, 2004; 62(2): 323 - 334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Sarmast, A. Kolli, A. Zaitsev, K. Parisian, A. S Dhamoon, P. K Guha, M. Warren, J. M.B Anumonwo, S. M Taffet, O. Berenfeld, et al. Cholinergic atrial fibrillation: IK,ACh gradients determine unequal left/right atrial frequencies and rotor dynamics Cardiovasc Res, October 1, 2003; 59(4): 863 - 873. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Xie, Z. Qu, A. Garfinkel, and J. N. Weiss Electrical refractory period restitution and spiral wave reentry in simulated cardiac tissue Am J Physiol Heart Circ Physiol, July 1, 2002; 283(1): H448 - H460. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Kneller, R. Zou, E. J. Vigmond, Z. Wang, L. J. Leon, and S. Nattel Cholinergic Atrial Fibrillation in a Computer Model of a Two-Dimensional Sheet of Canine Atrial Cells With Realistic Ionic Properties Circ. Res., May 17, 2002; 90 (9): e73 - e87. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Jalife, O. Berenfeld, and M. Mansour Mother rotors and fibrillatory conduction: a mechanism of atrial fibrillation Cardiovasc Res, May 1, 2002; 54(2): 204 - 216. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Nattel Therapeutic implications of atrial fibrillation mechanisms: can mechanistic insights be used to improve AF management? Cardiovasc Res, May 1, 2002; 54(2): 347 - 360. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. G. Kleber The fibrillating atrial myocardium. What can the detection of wave breaks tell us? Cardiovasc Res, November 1, 2000; 48(2): 181 - 184. [Full Text] [PDF]
|
|