Angiopathy
Encyclopedia
Angiopathy is the generic term for a disease of the blood vessel
s (arteries
, vein
s, and capillaries
). The best known and most prevalent angiopathy is diabetic angiopathy, a common complication
of chronic
diabetes.
and microangiopathy. In macroangiopathy, atherosclerosis
and a resultant blood
clot forms on the large blood vessels, sticks to the vessel walls, and blocks the flow of blood
. In microangiopathy, the walls of the smaller blood vessels become so thick and weak that they bleed, leak protein
, and slow the flow of blood through the body. The decrease of blood flow through stenosis
or clot formation impairs the flow of oxygen
to cell
s and biological tissue
s (called ischemia
) and leads to cellular death (necrosis
and gangrene
, which in turn may require amputation
). Thus, tissues which are very sensitive to oxygen levels, such as the retina
, develop microangiopathy and may cause blindness
(so-called proliferative diabetic retinopathy
). Damage to nerve
cells may cause peripheral neuropathy, and to kidney
cells, diabetic nephropathy
(Kimmelstiel-Wilson syndrome).
Microangiopathy, on the other hand, may cause other complications, such as ischemic heart disease, stroke
and peripheral vascular disease which contributes to the diabetic foot ulcers and the risk of amputation.
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
s (arteries
Artery
Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries....
, vein
Vein
In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...
s, and capillaries
Capillary
Capillaries are the smallest of a body's blood vessels and are parts of the microcirculation. They are only 1 cell thick. These microvessels, measuring 5-10 μm in diameter, connect arterioles and venules, and enable the exchange of water, oxygen, carbon dioxide, and many other nutrient and waste...
). The best known and most prevalent angiopathy is diabetic angiopathy, a common complication
Complication (medicine)
Complication, in medicine, is an unfavorable evolution of a disease, a health condition or a medical treatment. The disease can become worse in its severity or show a higher number of signs, symptoms or new pathological changes, become widespread throughout the body or affect other organ systems. A...
of chronic
Chronic (medicine)
A chronic disease is a disease or other human health condition that is persistent or long-lasting in nature. The term chronic is usually applied when the course of the disease lasts for more than three months. Common chronic diseases include asthma, cancer, diabetes and HIV/AIDS.In medicine, the...
diabetes.
By caliber
There are two types of angiopathy: macroangiopathyMacroangiopathy
-Pathophysiology:In macroangiopathy, fat and blood clots build up in the large blood vessels, stick to the vessel walls, and block the flow of blood....
and microangiopathy. In macroangiopathy, atherosclerosis
Atherosclerosis
Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol...
and a resultant blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
clot forms on the large blood vessels, sticks to the vessel walls, and blocks the flow of blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
. In microangiopathy, the walls of the smaller blood vessels become so thick and weak that they bleed, leak protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
, and slow the flow of blood through the body. The decrease of blood flow through stenosis
Stenosis
A stenosis is an abnormal narrowing in a blood vessel or other tubular organ or structure.It is also sometimes called a stricture ....
or clot formation impairs the flow of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
to cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
s and biological tissue
Biological tissue
Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
s (called ischemia
Ischemia
In medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...
) and leads to cellular death (necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
and gangrene
Gangrene
Gangrene is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies . This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood...
, which in turn may require amputation
Amputation
Amputation is the removal of a body extremity by trauma, prolonged constriction, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for...
). Thus, tissues which are very sensitive to oxygen levels, such as the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
, develop microangiopathy and may cause blindness
Blindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
(so-called proliferative diabetic retinopathy
Retinopathy
Retinopathy is a general term that refers to some form of non-inflammatory damage to the retina of the eye. Frequently, retinopathy is an ocular manifestation of systemic disease.-Pathophysiology:Causes of retinopathy are varied:...
). Damage to nerve
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
cells may cause peripheral neuropathy, and to kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
cells, diabetic nephropathy
Nephropathy
Nephropathy refers to damage to or disease of the kidney. An older term for this is nephrosis.-Causes:Causes of nephropathy include administration of analgesics, xanthine oxidase deficiency, and long-term exposure to lead or its salts...
(Kimmelstiel-Wilson syndrome).
Microangiopathy, on the other hand, may cause other complications, such as ischemic heart disease, stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
and peripheral vascular disease which contributes to the diabetic foot ulcers and the risk of amputation.
By condition
It is also possible to classify angiopathy by the associated condition:- Diabetic angiopathyDiabetic angiopathyDiabetic angiopathy is a form of angiopathy associated with diabetes mellitus. While not exclusive, the two most common forms are Diabetic retinopathy and Diabetic nephropathy, whose pathophysiologies are largely identical.-Pathophysiology:...
- Congophilic angiopathyCongophilic angiopathyCerebral amyloid angiopathy , also known as congophilic angiopathy, is a form of angiopathy in which amyloid deposits form in the walls of the blood vessels of the central nervous system...