SOD2 and cardiac arrhythmia: Infarct size ↓; CK-total and CK-MB ↓; inflammatory cell infiltrate, fibrotic area, and total collagen ↓; ST-segment, heart rate, and QTc interval ↓; Ca2+ ↓; mitochondrial density and ROS generation ↓; enzymatic activity of GPX, total SOD, Mn-SOD, and Cu–Zn-SOD activities ↑; LVDP and +dp/dt ↑; arrhythmia score ↓