Three-dimensional organisation of re-entrant propagation during experimental ventricular fibrilation

V.N. Biktashev, A.V. Holden , S.F. Mironov, A.M. Pertsov, A.V. Zaitsev

Published: CSF 13(8): 1713-1733, 2002

Ventricular fibrillation is believed to be produced by the breakdown of re-entrant propagation waves of excitation into multiple re-entrant sources. These re-entrant waves may be idealised as spiral waves in two dimensional, and scroll waves in three dimensional excitable media. Optically monitored, simultaneously recorded endocardial and epicardial patterns of activation on the ventricular wall not always show spiral waves. Analysis of optically recorded irregular electrical wave activity on the surface of the heart during experimentally induced fibrillation reveals a strong local temporal periodicity. The spatial distribution of the dominant temporal frequencies of excitation has a domain organization. The domains are large (~1cm^2) and they persist for minutes. We show that numerical simulations, even with a simple homogeneous excitable medium, can reproduce the key features of the simultaneous endo- and epicardial visualisations of propagating activity, and so these recordings may be interpreted in terms of scroll waves within the ventricular wall.