Spatial Autocorrelation Dimension (D_i ) for the Characterisation of Atrial Fibrillatory Dynamics

AF may be considered as a state of spatiotemporal disorder. As such, the behaviour of well-studied disordered systems in nature could be used to understand and predict AF dynamics. In this paper we review the scientific basis of a novel means of quantifying disorder in AF, namely spatial autocorrelation dimension (D_i ), which reflects the ratio of system size to spatial synchronisation, and relate it to the clinical entity of AF. In disordered systems, system size and spatial synchronisation determine behaviour; similarly, atrial size is a key determinant of clinical outcomes in AF, and spatial synchronisation may be quantified using the self-similarity of nearby electrograms with increasing distance. The advantage of this approach over the established paradigms of AF dynamics is that it allows AF to be studied according to the principles of disordered systems, ubiquitous across nature. It permits us to emerge from limitations imposed by the traditional theories of understanding AF, which have led to stagnant clinical outcomes in recent decades.