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DY: Fachverband Dynamik und Statistische Physik

DY 81: Nonlinear Dynamics, Synchronization, Chaos II

DY 81.5: Vortrag

Freitag, 16. März 2018, 11:15–11:30, BH-N 243

Mechanism of underdrive pacing for low-energy defibrillation — •Pavel Buran, Markus Bär, and Thomas Niedermayer — Physikalisch-Technische Bundesanstalt (PTB), Berlin

Rotating excitation waves and electrical turbulence in cardiac tissue are associated with arrhythmias such as life-threatening ventricular fibrillation. Experimental studies have shown that a sequence of low-energy electrical far-field pulses is able to terminate fibrillation more gently than a single high-energy pulse. During this low-energy antifibrillation pacing (LEAP), only tissue near sufficiently large conduction heterogeneities, such as large coronary arteries, is activated. Theoretical approaches to understand LEAP have often focussed on unpinning and removal of a small number of stable spirals and suggest LEAP protocols using overdrive or underdrive pacing or combinations of it. In this talk, we demonstrate that for typical cellular models, which exhibit stable pinned spirals, the process of unpinning and drift of spirals does not appear during successful LEAP. We present an alternative mechanism of underdrive pacing, which explains both the termination of stable spirals and spatiotemporal chaos.