Mechanisms of vortices termination in the cardiac muscle
We propose a solution to a long standing problem: how to terminate multiple vortices in the heart, when the locations of their cores and their critical time windows are unknown. We scan the phases of all pinned vortices in parallel with electric field pulses (E-pulses). We specify a condition on pacing parameters that guarantees termination of one vortex. For more than one vortex with significantly different frequencies, the success of scanning depends on chance, and all vortices are terminated with a success rate of less than one. We found that a similar mechanism terminates also a free (not pinned) vortex. A series of about 500 experiments with termination of ventricular fibrillation by E-pulses in pig isolated hearts is evidence that pinned vortices, hidden from direct observation, are significant in fibrillation. These results form a physical basis needed for the creation of new effective low energy defibrillation methods based on the termination of vortices underlying fibrillation.
The research leading to the results has received funding from Max Planck Gesellschaft, the European Community Seventh Framework Pro- gramme FP7/2007-2013 under Grant Agreement 17 No. HEALTH-F2-2009-241526, EUTrigTreat (DH, TB, SB, VIK, SL), and from EPSRC (UK) grant EP/I029664 (VNB).We also acknowledge support from the German Federal Ministry of Education and Research (BMBF) (project FKZ 031A147, GO-Bio), the German Research Foundation (DFG) (Collaborative Research Centres SFB 1002 Project C3 and SFB 937 Project A18), the Ger- man Center for Cardiovascular Research (DZHK e.V.) (DH, TB, SB, VIK, SL), Science & Engineering Research Board of Department of Science & Technology, Govern- ment of India (TKS), EPSRC (UK) grant EP/N014391 (VNB) and U.S. NIH Grant No. R01HL089271 (NFO).