Lessons from computer simulations of ablation of atrial fibrillation

Abstract

This paper reviews the simulations of catheter ablation in computer models of the atria, from the first attempts to the most recent anatomical models. It describes how postulated substrates of atrial fibrillation can be incorporated into mathematical models, how modelling studies can be designed to test ablation strategies, what their current trade-offs and limitations are, and what clinically relevant lessons can be learnt from these simulations. Drawing a parallel between clinical and modelling studies, six ablation targets are considered: pulmonary vein isolation, linear ablation, ectopic foci, complex fractionated atrial electrogram, rotors and ganglionated plexi. The examples presented for each ablation target illustrate a major advantage of computer models, the ability to identify why a therapy is successful or not in a given atrial fibrillation substrate. The integration of pathophysiological data to create detailed models of arrhythmogenic substrates is expected to solidify the understanding of ablation mechanisms and to provide theoretical arguments supporting substrate-specific ablation strategies.

Figure 1. Schematic recapitulation of the types of ablation patterns tested and compared in computer models

The horizontal axis symbolises the evolution of the substrate from paroxysmal (left) to persistent/permanent AF (right) and the vertical axis corresponds to the type of ablation patterns with increasing complexity (from top to bottom). Each circle represents a family of tested patterns. The number of patterns in each family is written within the circle. The lines connecting the circles indicate that a statistical comparison between the patterns has been performed. The value of n is the number of AF episodes simulated per group. The number of patients is reported in the case of patient‐specific models. PVI: pulmonary vein isolation.