A fatty streak is the first grossly visible (visible to the naked eye) lesion in the development of atherosclerosis. It appears as an irregular yellow-white discoloration on the luminal surface of an artery. It consists of aggregates of foam cells, which are lipoprotein-loaded macrophages, [1] located in the intima, the innermost layer of the artery, beneath the endothelial cells that layer the lumina through which blood flows. Fatty streaks may also include T cells, aggregated platelets, and smooth muscle cells. Although fatty streaks can develop into atheromas (atheromatous plaques), not all are destined to become advanced lesions. [2]
Almost all children older than 10 in developed countries have aortic fatty streaks, with coronary fatty streaks beginning in adolescence. [3] [4] [5]
In 1953, a study was published that forever changed the understanding of the development of heart disease. The study examined the results of 300 autopsies performed on U.S. soldiers who had died in the Korean War. Despite the fact that the average age of the soldiers was just 22 years old, 77% of them had visible signs of coronary atherosclerosis. This study showed that heart disease could affect people at a young age and was not just a problem for older individuals. [6] [7] [8]
In 1992, a report had shown that microscopic fatty streaks were noticed in the left anterior descending artery in over 50% of children aged 10–14. And 8% had more notable accumulations of extracellular lipid. [9]
In a 2005 study carried out between 1985–1995, it was found that around 87% of aortas and 30% of coronary arteries in age group 5–14 years had fatty streaks. [10]
Atherosclerosis is a pattern of the disease arteriosclerosis, characterized by development of abnormalities called lesions in walls of arteries. These lesions may lead to narrowing of the arteries' walls due to buildup of atheromatous plaques. At onset there are usually no symptoms, but if they develop, symptoms generally begin around middle age. In severe cases, it can result in coronary artery disease, stroke, peripheral artery disease, or kidney disorders, depending on which body parts(s) the affected arteries are located in the body.
A thrombus, colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of cross-linked fibrin protein. The substance making up a thrombus is sometimes called cruor. A thrombus is a healthy response to injury intended to stop and prevent further bleeding, but can be harmful in thrombosis, when a clot obstructs blood flow through healthy blood vessels in the circulatory system.
Arteriosclerosis is a vascular disorder characterized by abnormal thickening, hardening, and loss of elasticity of the walls of arteries; this process gradually restricts the blood flow to one's organs and tissues and can lead to severe health risks brought on by atherosclerosis, which is a specific form of arteriosclerosis caused by the buildup of fatty plaques, cholesterol, and some other substances in and on the artery walls.
Microangiopathy is a disease of the microvessels, small blood vessels in the microcirculation. It can be contrasted to macroangiopathies such as atherosclerosis, where large and medium-sized arteries are primarily affected.
The endothelium is a single layer of squamous endothelial cells that line the interior surface of blood vessels and lymphatic vessels. The endothelium forms an interface between circulating blood or lymph in the lumen and the rest of the vessel wall. Endothelial cells form the barrier between vessels and tissue and control the flow of substances and fluid into and out of a tissue.
Infarction is tissue death (necrosis) due to inadequate blood supply to the affected area. It may be caused by artery blockages, rupture, mechanical compression, or vasoconstriction. The resulting lesion is referred to as an infarct (from the Latin infarctus, "stuffed into").
Coronary thrombosis is defined as the formation of a blood clot inside a blood vessel of the heart. This blood clot may then restrict blood flow within the heart, leading to heart tissue damage, or a myocardial infarction, also known as a heart attack.
An atheroma, or atheromatous plaque, is an abnormal accumulation of material in the inner layer of an arterial wall.
A vulnerable plaque is a kind of atheromatous plaque – a collection of white blood cells and lipids in the wall of an artery – that is particularly unstable and prone to produce sudden major problems such as a heart attack or stroke.
In vascular diseases, endothelial dysfunction is a systemic pathological state of the endothelium. Along with acting as a semi-permeable membrane, the endothelium is responsible for maintaining vascular tone and regulating oxidative stress by releasing mediators, such as nitric oxide, prostacyclin and endothelin, and controlling local angiotensin-II activity.
Dactylitis or sausage digit is inflammation of an entire digit, and can be painful.
Vasospasm refers to a condition in which an arterial spasm leads to vasoconstriction. This can lead to tissue ischemia and tissue death (necrosis). Cerebral vasospasm may arise in the context of subarachnoid hemorrhage. Symptomatic vasospasm or delayed cerebral ischemia is a major contributor to post-operative stroke and death especially after aneurysmal subarachnoid hemorrhage. Vasospasm typically appears 4 to 10 days after subarachnoid hemorrhage.
Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes.
An arteriovenous fistula is an abnormal connection or passageway between an artery and a vein. It may be congenital, surgically created for hemodialysis treatments, or acquired due to pathologic process, such as trauma or erosion of an arterial aneurysm.
Arteriolosclerosis is a form of cardiovascular disease involving hardening and loss of elasticity of arterioles or small arteries and is most often associated with hypertension and diabetes mellitus. Types include hyaline arteriolosclerosis and hyperplastic arteriolosclerosis, both involved with vessel wall thickening and luminal narrowing that may cause downstream ischemic injury. The following two terms whilst similar, are distinct in both spelling and meaning and may easily be confused with arteriolosclerosis.
Foam cells, also called lipid-laden macrophages, are a type of cell that contain cholesterol. These can form a plaque that can lead to atherosclerosis and trigger myocardial infarction and stroke.
In pathology, Anitschkowcells are often cells associated with rheumatic heart disease. Anitschkow cells are enlarged macrophages found within granulomas associated with the disease.
Fat necrosis is a form of necrosis that is caused by the action of lipases on adipocytes.
The chronic endothelial injury hypothesis is one of two major mechanisms postulated to explain the underlying cause of atherosclerosis and coronary heart disease (CHD), the other being the lipid hypothesis. Although an ongoing debate involving connection between dietary lipids and CHD sometimes portrays the two hypotheses as being opposed, they are in no way mutually exclusive. Moreover, since the discovery of the role of LDL cholesterol (LDL-C) in the pathogenesis of atherosclerosis, the two hypotheses have become tightly linked by a number of molecular and cellular processes.
Russell Ross (1929–1999) was an American professor of pathology, known for research on the pathogenesis of atherosclerosis.