Coronary Artery Atherosclerosis: Types And Lesion Characteristics

Coronary artery atherosclerosis is typically best understood through post-mortem examination, especially in patients who have passed away due to complications of the disease. However, with advancements in medical technology, certain in vivo diagnostic tools such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT) now allow physicians to analyze the composition and structure of arterial plaques to some extent while the patient is still alive.

Classification Of Atherosclerotic Plaques

When categorizing the pathology of atherosclerosis, stable plaques can generally be divided into three main types. The most common and prevalent type is fibrous plaque, which tends to be less volatile and more structurally stable. Another type, calcified plaque, is less common overall but more frequently observed in elderly patients. These plaques contain hardened, calcium-rich deposits that can grow within the vessel wall and contribute to narrowing or even blockage of the artery.

Microscopic And Advanced Plaque Development

In most patients, the plaques observed are microscopic in size. However, approximately one-third of individuals, especially those of advanced age, may develop calcified plaques that resemble small stones in texture. These harder plaques can significantly impact treatment planning, influencing decisions regarding interventions such as angioplasty, stenting, or coronary artery bypass grafting (CABG).

Lipid-Rich Plaques And Their Risks

Lipid plaques refer to larger accumulations of fatty deposits within the arterial wall. These plaques appear softer on imaging studies and are composed primarily of cholesterol and other lipids. When a patient experiences an acute cardiovascular event, such as a heart attack, it is often due to the rupture of a lipid-rich plaque followed by the formation of a thrombus (blood clot). This process can severely restrict or completely block blood flow, leading to life-threatening complications.