Conclusion
Charge density mapping facilitates identification of complex patterns of wavefront propagation during atrial fibrillation. Although irregular activation patterns characterised by changing wavefront direction, and high frequency focal firing are spatially stable, rotational activations are transient and meandering, with low spatial stability. The duration of mapping recording used significantly impacts the results obtained. A minimum duration of 20s is required to identify regions of repetitive but transient rotational activation whilst shorter segments will accurately reveal regions with high frequency irregular and focal activation. These stable regions of irregular activation may best reflect underlying atrial structural abnormalities and represent important sites for catheter ablation approaches.