The goal of this observational cohort study is to establish a risk prediction model for adverse events in Chinese individuals under 45 years old with premature coronary artery disease. The main questions it aims to answer are:
* What are the major risk factors for poor prognosis in Chinese patients with premature coronary artery disease?
* What is the difference in the prognosis of patients with premature coronary heart disease with different phenotypes? Participants taking no mandatory intervention will be followed up for 2 year, with blood tests at 1 year and outpatient or telephone interviews at other timepoints.