PCSK9 and atherosclerosis: Cluster one is in red and contains 42 keywords, including: PCSK9, cardiovascular disease, familial hypercholesterolemia, atherosclerosis, gene expression, mutation, cholesterol, LDLR, etc. Cluster II is in green color and contains 35 keywords, including: PCSK9 inhibitor, evolocumab, alirocumab, statin therapy, cardiovascular risk, safety, efficiency, and so on.