Microangiopathy


Microangiopathy is an angiopathy affecting small blood vessels in the body. It can be contrasted to macroangiopathy, or large vessel disease.
Cerebral small vessel disease refers to a group of diseases that affect the small arteries, arterioles, venules, and capillaries of the brain. Age-related and hypertension-related small vessel diseases and cerebral amyloid angiopathy are the most common forms.
Coronary small vessel disease is a type of coronary heart disease that affects the arterioles and capillaries of the heart. Coronary small vessel disease is also known as microvascular angina, microvascular dysfunction, non-obstructive coronary disease, or in the past, cardiac syndrome X.

Pathophysiology

One cause of microangiopathy is long-term diabetes mellitus. In this case, high blood glucose levels cause the endothelial cells lining the blood vessels to take in more glucose than normal. They then form more glycoproteins on their surface than normal, and also cause the basement membrane in the vessel wall to grow abnormally thicker and weaker. Therefore they bleed, leak protein, and slow the flow of blood through the body. As a result, some organs and tissues do not get enough blood and are damaged, for example, the retina or kidney. Nerves and neurons, if not sufficiently supplied with blood, are also damaged, which leads to loss of function.
Massive microangiopathy may cause microangiopathic hemolytic anemia.

Therapy

See therapy of arteriosclerosis.
Laser therapy of diabetic retinopathy.
A number of medicines, such as calcium dobesilate, are being marketed for the specific treatment of microangiopathy. The efficacy of calcium dobesilate has been described e.g. in patients with diabetic retinopathy or diabetic nephropathy.