A paradigm shift in myocardial stunning.

this lateralization may result in a change in anisotropy, which was supported by our rat model. In that model a higher degree of lateralization was seen than observed in human chronic AF. However, it is difficult to extrapolate from the rat experiments to the human immunostaining results, for we cannot know how much of the protein positively staining for connexins resembles functional channels. In the rat model did we observe both lateralization and changes in anisotropy. However, we completely agree with van der Velden and colleagues that inhomogenicities in connexin distribution as described in their study in a goat model (3) should have a high impact on the biophysics of the tissue. In contrast to our findings in humans, they describe a decrease in Cx40, which from our point of view might either be due to species difference or to the fact that they investigated goat atria during the first 16 weeks of sustained pacing, while we investigated chronic AF of one-year duration in patients.