2. Definitions

ASCVD refers to all clinical conditions of atherosclerotic origin, including acute coronary syndrome (ACS), myocardial infarction (MI), stable or unstable angina, coronary artery disease documented using angiography, coronary or other arterial revascularization (coronary artery bypass graft surgery, femoral-popliteal bypass graft surgery, etc), stroke, transient ischemic attack, documented carotid disease, peripheral artery disease, and abdominal aortic aneurysm. Statin-indicated condition refers to any condition for which pharmacotherapy with statins is indicated, and consists of all documented ASCVD conditions, as well as other high-risk primary prevention conditions in the absence of ASCVD, such as most patients with diabetes, those with chronic kidney disease (CKD), and those with an LDL-C ≥ 5.0 mmol/L or a diagnosis of familial hypercholesterolemia (FH). This concept was first introduced in the 2016 guidelines and continues to be used in this update. Primary prevention refers to all efforts aimed at either populations or individuals to prevent or delay the onset of ASCVD. Secondary prevention refers to the efforts to treat known, clinically significant ASCVD, and to prevent or delay the onset of disease manifestations.