CD44 and atrial fibrillation: The regions that correspond to the Sca-1+-CD44+ subgroup, which stand for MSCs, are indicated on the Gaussian curves for the Non-Rec cells (average values of 595.3 ± 11.8 Pa, 674.0 ± 19.2 Pa and 39.6 ± 1.4 nN for CS, TS and AF, respectively) and the Rec cells (average values of 641.3 ± 21.2 Pa, 700.3 ± 31.1 Pa and 43.8 ± 1.9 nN for CS, TS and AF, respectively) (Figure 2D,E and F).