Comparison to prior work on conductive materials
It is important to consider these findings in light of prior data on the impact of conductive materials on cell-cell interaction in the heart. We have previously reported data on the use of 3D-printed patches to restore conduction across disrupted areas of myocardial activation(12). This has similarly been demonstrated by others. However, scar and arrhythmogenic circuits are often multi-dimensional and not simply reflected along a single surface. Thus, identifying ways to enhance conduction not just along the surface (whether endocardially or epicardially) but transmurally may be critical when developing a solution that may be antiarrhythmic. Each will have theoretical benefits and limitations – a patch may be less invasive, reversible, and easier to apply with a lower risk of complications due to lack of need to inject directly into myocardial tissue. However, injection approaches may more directly address the conduction heterogeneity attributable to 3-dimensional complexity that is likely seen in most cases of scar-related arrhythmia.
Furthermore, prior work has suggested that other materials aside from carbon nanotubes may allow for enhanced conduction between otherwise electrically disconnected myocytes. We did not directly compare the effects of our material with these other materials. However, most work has been on creating a surface over which cells are placed and then evaluating conduction rather than methods that may facilitate enhanced conduction transmurally. Determination of the optimal conductive materials based on chronic maintenance of conduction and biocompatibility will require further study.