Coronary artery disease (CAD) is one of the major diseases that threaten human health, and clinically, there is a tendency to classify the disease into two major categories: acute coronary syndromes and chronic ischemic syndromes. Although the underlying etiology of the disease is not well understood, extensive and in-depth studies conducted over half a century on common coronary artery atherosclerosis have shown that the disease is multi-causal (i.e., caused by multiple factors acting on different links) and that its causative (risk) factors are relatively clear, the most important of which are hypertension, dyslipidemia (various), impaired glucose metabolism, obesity, smoking, lack of exercise and The most important factors are hypertension, dyslipidemia (various), impaired glucose metabolism, obesity, smoking, lack of exercise and psychological stress (in recent years, obesity, dyslipidemia, hypertension, type 2 diabetes and abnormal glucose tolerance are called “metabolic syndrome”); as people’s living standards continue to improve, unhealthy lifestyles have increased the relative and absolute incidence of the disease, and it is now among the leading causes of death in the population. Premature coronary artery disease (PCAD) is a special form of coronary artery disease (CAD), defined as CAD occurring at the age of <55 years for men and <65 years for women, and domestic and international studies have shown that the incidence of premature coronary artery disease is occurring at a significant rate in young people. The impact of early-onset coronary artery disease is not only huge for the patients themselves, but also for their families, and has a certain socio-economic impact. This raises a question for medical practitioners: how to recognize and detect the risk factors of early-onset coronary heart disease early, especially those that can be changed, so that changes can be made before they happen and prevention can be made before they happen; in this way, even when early-onset coronary heart disease occurs, the most active and effective measures can be provided to minimize its harm, so it is necessary to strengthen the research on early-onset coronary heart disease. There is a greater aggregation of cardiovascular risk factors in patients with early-onset coronary artery disease, and most of these risk factors can be controlled and improved. For those with a family history of early-onset coronary heart disease, more aggressive primary prevention is advocated, starting with children to promote a healthy lifestyle of no smoking, no alcohol consumption, and a low-salt, low-fat, low-saturated fatty acid diet. Although patients with early-onset coronary artery disease have mainly single-branch lesions and less severe lesions than patients with late-onset coronary artery disease, due to the relatively short disease duration of patients with early-onset coronary artery disease, the atherosclerotic plaques are mainly composed of lipid components with fewer fibrous components and thinner fibrous caps (i.e., soft plaques), which are prone to rupture and lead to acute adverse cardiovascular events, and because of the mild lesions and short disease duration, the collateral circulation is rare or not yet formed. Once acute coronary events occur, the prognosis may be poor due to the lack of compensation of collateral circulation, so early diagnosis and early intervention in patients with early-onset coronary artery disease are especially important.