Discriminating at-risk post-MI patients by fractal dimension analysis of the late potential attractor

A novel and reliable approach which quantifies the degree of complexity of late potential (LP) activity in the time domain is presented. By defining the LP attractor in the microvoltage, 3-dimensional space, and then computing the fractal dimension (δ) of the attractor´s trajectory, the degree of complexity of LP can be quantified with a single parameter. δ may indicate the chaotic behaviour of the terminal activity of the ventricular depolarisation process. The fractal dimension of the LP Attractor in post-MI subjects that are at risk is significantly higher than in post-MI subjects with low LP activity (p<0.001). δ may be considered as the criterion for discrimination. Fractal dimension analysis on LP is a novel diagnostic approach aimed at quantifying their complexity in the microvoltage 3-D space, and may be interpreted as a measure of their chaotic behaviour triggering a catastrophic arrhythmic episode