| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Physics Department, Hofstra University, Hempstead, NY, USA
2 Physics Department, Hofstra University, Hempstead, NY, USA; The Heart Institute, Beth Israel Medical Center, New York, NY, USA
* To whom correspondence should be addressed. E-mail: fenton{at}presto.physics.neu.edu.
In this paper, we examine the utility of the action potential duration (APD) restitution curve slope in predicting the onset of electrical alternans when electrotonic and memory effects are considered. We develop and use two ionic cell models without memory that have the same restitution curve with slope greater than one but different action potential shapes, and therefore different electrotonic effects. We also study a third cell model that incorporates short-term memory of previous cycle lengths, so that it has a family of S1- S2 restitution curves as well as a dynamic restitution curve whose slope is greater than one. Our results indicate that both electrotonic and memory effects can suppress alternans even when the APD restitution curve is steep. In the absence of memory, electrotonic currents related to the shape of the action potential as well as conduction velocity (CV) restitution can affect how alternans develops in tissue and in some cases can prevent its induction entirely even when isolated cells exhibit alternans. When short-term memory is included, alternans may not occur in isolated cells despite a steep APD restitution curve, and may or may not occur in tissue depending on CV restitution. We show for the first time that electrotonic and memory effects can prevent conduction blocks and stabilize reentrant waves in 2D and 3D. Thus, we find that the slope of the APD restitution curve alone does not always well predict the onset of alternans, and incorporating electrotonic and memory effects may provide a more useful alternans criterion.
This article has been cited by other articles:
|
|
 |
|
  C. L. del Rio, T. A. Dawson, B. D. Clymer, D. J. Paterson, and G. E. Billman Effects of acute vagal nerve stimulation on the early passive electrical changes induced by myocardial ischaemia in dogs: heart rate-mediated attenuation Exp Physiol, August 1, 2008; 93(8): 931 - 944. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. H. Keldermann, K. H. W. J. ten Tusscher, M. P. Nash, R. Hren, P. Taggart, and A. V. Panfilov Effect of heterogeneous APD restitution on VF organization in a model of the human ventricles Am J Physiol Heart Circ Physiol, February 1, 2008; 294(2): H764 - H774. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. E. Bondarenko and R. L. Rasmusson Simulations of propagated mouse ventricular action potentials: effects of molecular heterogeneity Am J Physiol Heart Circ Physiol, September 1, 2007; 293(3): H1816 - H1832. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. M. Pitruzzello, W. Krassowska, and S. F. Idriss Spatial heterogeneity of the restitution portrait in rabbit epicardium Am J Physiol Heart Circ Physiol, March 1, 2007; 292(3): H1568 - H1578. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. A. Ng, K. E. Brack, V. H. Patel, and J. H. Coote Autonomic modulation of electrical restitution, alternans and ventricular fibrillation initiation in the isolated heart Cardiovasc Res, March 1, 2007; 73(4): 750 - 760. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. M. Cherry and F. H. Fenton A tale of two dogs: analyzing two models of canine ventricular electrophysiology Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H43 - H55. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. C. Knollmann, T. Schober, A. O. Petersen, S. G. Sirenko, and M. R. Franz Action potential characterization in intact mouse heart: steady-state cycle length dependence and electrical restitution Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H614 - H621. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. H. W. J. ten Tusscher and A. V. Panfilov Alternans and spiral breakup in a human ventricular tissue model Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1088 - H1100. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Allouis, F. Le Bouffant, R. Wilders, D. Peroz, J.-J. Schott, J. Noireaud, H. Le Marec, J. Merot, D. Escande, and I. Baro 14-3-3 Is a Regulator of the Cardiac Voltage-Gated Sodium Channel Nav1.5 Circ. Res., June 23, 2006; 98(12): 1538 - 1546. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. M. Narayan T-Wave Alternans and the Susceptibility to Ventricular Arrhythmias J. Am. Coll. Cardiol., January 17, 2006; 47(2): 269 - 281. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. N. Healy and A. D. McCulloch An ionic model of stretch-activated and stretch-modulated currents in rabbit ventricular myocytes Europace, January 1, 2005; 7(s2): S128 - S134. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. Qu Dynamical effects of diffusive cell coupling on cardiac excitation and propagation: a simulation study Am J Physiol Heart Circ Physiol, December 1, 2004; 287(6): H2803 - H2812. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
