Figure 3.

The Box: Adequate exclusion of the entire posterior LA. A satisfactory result with long-term efficacy relies on isolation of the entire posterior LA. Specifically, a box-shaped area of tissue, incorporating the ostia of all PVs and the intervening posterior LA wall, must be electrically excluded via a continuous and fully transmural circumferential line of ablation. Note that this box does not need to be made with a single application of a device, but can be constructed from a number of applications.