TET2 and atrial fibrillation: Expansion of Tet-deficient hematopoietic cells inversely correlated with significant shortening of the RA APD (Figure S5E), mimicking the association between VAF and incident AF observed in human cohort studies and consistent with AF susceptibility with abbreviated AERP and APD.9,31,36,37 This is also consistent with murine models requiring significant alterations to elicit AF, and more pronounced phenotypes in mouse models of CHIP with loss of Tet2 in hematopoietic lineages.3,9,28,31,38