CASP7 and atrial fibrillation: Palmitic acid is one of the most abundant free fatty acids (FFAs) in plasma, accounting for 27% of total plasma FFA.[42] Palmitic acid can activate caspase-3 and caspase-7 in cardiomyocytes, leading to cardiomyocyte apoptosis.[43] It was also found that the levels of palmitic acid in the AF and AF + CHD groups were significantly higher than those in the CHD and NC groups.