Atheroma 粥腫

Atheroma

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Atheroma
Classification and external resources
Atherosclerotic plaque from a carotid endarterectomy specimen. This shows the bifurcation of the common into the internal and external carotid arteries.
ICD-10	I70.9
ICD-9	440
DiseasesDB	1039
MeSH	C14.907.137.126.307

In pathology, an atheroma (from ἀθήρωμα (athērōma)=“tumor full gruel-like matter”) is an accumulation and swelling in artery walls that is made up of (mostly macrophage cells), or debris, that contain lipids (cholesterol and fatty acids), calcium and a variable amount of fibrous connective tissue. In the context of heart or artery matters, atheromata are commonly referred to as atheromatous plaques. It is an unhealthy condition, but is found in most humans.^[1]

These anatomic lesions usually begin in some children younger than age 1 year and all children older than age 10 regardless of geography, race, sex or environment. Veins do not develop atheromata, unless surgically moved to function as an artery, as in bypass surgery. The accumulation (swelling) is always between the endothelium lining and the smooth muscle wall central region (media) of the arterial tube, see IMT. While the early stages, based on gross appearance, have traditionally been termed fatty streaks by pathologists, they are not composed of fat cells, i.e. adipose cells, but of accumulations of white blood cells, especially macrophages that have taken up oxidized low-density lipoprotein (LDL). After they accumulate large amounts of cytoplasmic membranes (with associated high cholesterol content) they are called foam cells. When foam cells die, their contents are released, which attracts more macrophages and creates an extracellular lipid core near the center to inner surface of each atherosclerotic plaque. Conversely, the outer, older portions of the plaque become more calcific, less metabolically active and more physically stiff over time.

Collectively, the process of atheroma development within an individual is called atherogenesis and the overall result of the disease process is termed atherosclerosis or "hardening of the arteries."