Click on image to view larger version.

Figure 2 (Upper panels) Effects of 48 h of atrial fibrillation (AF) on atrial effective refractory period (AERP) in normal and dilated atria at pacing intervals between 400 and 200 ms (n = 7). In dilated atria, electrical remodeling shortened the AERP to a similar extent as in normal atria. (Lower panels) The time course of electrical remodeling (changes in AERP₃₅₀) during the first 48 h of AF in normal and dilated atria. *p < 0.05; **p < 0.01; ***p < 0.001.