AGT and atrial fibrillation: COX-2 is the major source of prostaglandins in inflammatory conditions and diseases such as cardiovascular disease.[54] The upregulation of COX-2 level was related to the release of atrial natriuretic peptide/brain natriuretic peptide and myocardial hypertrophy, and inhibition of COX-2 could reduce myocardial hypertrophy induced by angiotensin II.[55,56] In the AF + CHD group, an increase in 12-oxo-LTB4 was observed in the study.