Dresden 2009 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 1: Dynamic Processes and Pattern Formation

BP 1.1: Hauptvortrag

Montag, 23. März 2009, 10:15–10:45, HÜL 186

Taming a Heart Gone Wild — •Stefan Luther — Biomedical Physics Group, Max Planck Insitute for Dynamics and Self-Organization, Bunsenstrasse 10, 37073 Goettingen, Germany

Spatiotemporally chaotic wave dynamics underlie a variety of debilitating crises in extended excitable systems such as heart and brain. It is well known that control of spatiotemporal chaos requires multiple control sites. Creating such sites in living tissue, however, is a long-standing problem. Here we show that natural anatomical heterogeneities within cardiac tissue can provide a large and adjustable number of control sites for low-energy termination of malignant wave dynamics. This allows us to terminate ventricular fibrillation in canine cardiac tissue using small amplitude pulsed electric fields with up to two orders of magnitude lower energies than those used for defibrillating shocks. We quantify the physical mechanism underlying the creation of control sites using fully time resolved high-spatial resolution imaging of wave emission, high-resolution magnetic resonance imaging of cardiac structure, and cell culture experiments. Our method avoids the invasive implantation of multiple electrodes and, more importantly, has the potential to control the tissue where the chaotic state is most susceptible, i.e., at rotating wave cores. This approach promises to significantly enhance current technologies for the termination of life-threatening cardiac arrhythmias, a leading cause of mortality and morbidity in the industrialized world. Moreover, the method should be capable of regulating wave dynamics in other excitable systems, including the nervous system.