Alternans amplification following a two-stimulus protocol in a one-dimensional cardiac ionic model of reentry: from annihilation to double-wave quasiperiodic reentry.
Electrical pacing is a common procedure in both experimental and clinical settings to study and/or annihilate anatomical reentry. A previous study [Comtois and Vinet, Chaos 12, 903 (2002)] has described new ways to terminate reentry in a one-dimensional loop model by a protocol consisting of only two stimulations. Annihilation of the reentrant activity was much more likely with these new scenarios than through a unidirectional block. This paper investigates the sensitivity of these scenarios of annihilation to the length of the pathway. It shows that double-pulse stimulation can stop the reentry if the circuit is shorter than a limiting length. Beyond this upper limit, stimulation rather yields sustained double-wave reentry. The same dynamical mechanism, labeled alternans amplification, is found to be responsible for these two types of post-stimulus dynamics.
Comtois
P
P
Research Centre, Montreal Heart Institute and Department of Pharmacology, McGill University, Montreal, Quebec, H3G 1Y6, Canada.
Vinet
A
A
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000628:therapy; D002304:Cardiac Pacing, Artificial / Q000379:methods* / Q000706:statistics & numerical data; D003198:Computer Simulation; D004594:Electrophysiology; D006321:Heart / Q000502:physiology; D006801:Humans; D007477:Ions / Q000378:metabolism; D008955:Models, Cardiovascular; D009206:Myocardium / Q000378:metabolism
D007477:Ions