Atherosclerosis is the foundational pathology of coronary artery disease (CAD). It is a progressive inflammatory disease characterized by lipid deposition within the intima of the arterial wall, triggered by chronic endothelial injury from factors like tobacco smoking, hypertension, hyperlipidemia, and diabetes. The disease progresses through three key developmental stages over several decades:

1. Fatty Streak: The earliest lesions, consisting of lipid-filled smooth muscle cells that appear yellow, starting in coronary arteries by age 20.
2. Fibrous Plaque: Appearing by age 30, lipoproteins transport lipids into the intima, where collagen covers them to form a grayish-white plaque. This narrows the vessel lumen and reduces distal blood flow.
3. Complicated Lesion: ...