CASP3 and atrial fibrillation: In this study, we also found that AF cell apoptosis ratio, caspase-3/9 activity, and expression of proapoptotic molecules (Bax, caspase-3, cleaved caspase-3, and cleaved PARP) in the TNF-α group were significantly increased compared with those in the control group, confirming that inflammatory cytokine TNF-α can induce disc AF cell apoptosis.