Atherosclerosis is a chronic inflammatory disease of coronary arteries, affecting the structure and function of their wall. It is characterized by the progressive accumulation of lipids within the arterial wall, triggering a continuous inflammatory response. This process gradually leads to reduced arterial wall elasticity and lumen narrowing. Before clinical effects become visible, atherosclerotic plaques develop slowly and insidiously over decades (30-50 years). Investigating the plaque’s characteristics throughout its progression may provide valuable insights for preventing adverse events associated with long-term atherosclerosis. Intravascular optical coherence tomography (OCT) has revolutionised the understanding of atherosclerosis in coronary arteries, allowing early identification of vulnerable plaques.