Temporal complexity of early ventricular fibrillation (VF) is re-assessed t
hrough measuring the correlation dimension D-2. entropy K-2 and high-dimens
ional component sigma from electrocardiogram (ECG) recordings using the Gau
ssian kernel algorithm. Seven representative ECG tracts of induced VF among
53 pig subjects are selected for analysis. VF is found to have 80-90% low-
dimensional deterministic dynamics with D-2 varying around 5 and 10-20% hig
h-dimensional extents. (C) 2000 Elsevier Science B.V. All rights reserved.