Substrate ablation of low voltage areas (scarred areas are low voltage when mapped under sinus rhythm) has been gaining momentum in the last couple of years. I am not sure how it started but the germination of the idea probably has to do with the fundamental studies that imaged scars and how the scars behaved electrically compared to healthy tissue. Anyway, it has been proven over the last couple of years that disconnecting scar tissue either by thorough ablation (aka homogenisation) or box isolation increases long term success by a large margin for ischemic VT patients. I am not sure whether the idea was developed because of what is happening in VT ablation or it is being tested in AF ablation before VT. Below are a couple of papers that explain what is meant by substrate ablation. This idea is particularly germane to patients with late recurrence and complementary to the potential need for LAA ablation.
VT ablation - [
content.onlinejacc.org] (enlarge Figure 1 for explanation of protocol)
AF ablation - [
content.onlinejacc.org] (discussion of same concept as used in VT applied to AF with examples)
An important part of the concept is that the protocol would be best achieved by catheters that can do both mapping and ablation as the biophysics of the catheter doesn't change so that location identified by mapping is the same location contacted during ablation (after mapping).
Edited 1 time(s). Last edit at 01/07/2016 11:16AM by researcher.
