10.1063/5.0033813.1

Default Digital Object Group

Abstract

Excitable media sustain circulating waves. In the heart, sustained circulating waves can lead to serious impairment or even death. To investigate factors affecting the stability of such waves, we have used optogenetic techniques to stimulate a region at the apex of a mouse heart at a fixed delay after the detection of excitation at the base of the heart. For long delays, rapid circulating rhythms can be sustained, whereas for shorter delays, there are paroxysmal bursts of activity that start and stop spontaneously. By considering the dependence of the action potential and conduction velocity on the preceding recovery time using restitution curves, as well as the reduced excitability (fatigue) due to the rapid excitation, we model prominent features of the dynamics including alternation of the duration of the excited phases and conduction times, as well as termination of the bursts for short delays. We propose that this illustrates universal mechanisms that exist in biological systems for the self-termination of such activities.

Authors 8

1. Valentina Biasci

   University of Florence

   Affiliation as printed

   Division of Physiology, Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy

2. Leonardo Sacconi

   University of Freiburg · National Institute of Optics · National Research Council

   Affiliation as printed

   Institute for Experimental Cardiovascular Medicine, University of Freiburg, Freiburg,Germany

   National Institute of Optics, National Research Council, 50125 Florence, Italy

3. Eric N. Cytrynbaum

   University of British Columbia

   Affiliation as printed

   Department of Mathematics, UBC, Vancouver British Columbia V6T 1Z2, Canada

4. Daniël A. Pijnappels Aachen Department of Cardiology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Cardiology, Leiden University Medical Center, Albinusdreef 2 2333 ZA Leiden, The Netherlands

5. Tim De Coster Aachen Department of Cardiology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Cardiology, Leiden University Medical Center, Albinusdreef 2 2333 ZA Leiden, The Netherlands

6. Alvin Shrier

   McGill University

   Affiliation as printed

   Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montreal, Quebec H3G 1Y6, Canada

7. Leon Glass corresponding

   McGill University

   Affiliation as printed

   Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montreal, Quebec H3G 1Y6, Canada

8. Gil Bub

   McGill University

   Affiliation as printed

   Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montreal, Quebec H3G 1Y6, Canada