Arteriosclerosis - Definition
Often, the terms arteriosclerosis and atherosclerosis are used interchangeably as synonyms. In reality, these are two different and not perfectly superposable conditions:
the term arteriosclerosis identifies all forms of hardening, thickening and loss of elasticity of the arterial wall, such as atherosclerosis, arteriolosclerosis and calcific sclerosis of Mönckeberg: it is therefore a general term.
Atherosclerosis
Atherosclerosis is characterized by the formation of atheromas (plaques of lipid, protein and fibrous material) in the large and medium caliber muscle arteries (coronary, carotid and femoral) and in the elastic ones such as the aorta or pulmonary artery. Atherosclerosis, therefore, is a specific type of arteriosclerosis and - among all - it is the most frequent and clinically important form (first cause death in the western world); hence the widespread use of the two terms as synonyms.
Metabolic syndrome is the main factor predisposing atherosclerosis; further information is provided in this article.
Arteriolosclerosi
Arteriolosclerosis affects small-caliber arteries, particularly those of the kidney, spleen, liver and pancreas. Unlike atherosclerosis it does not involve the formation of lipid deposits, but of abnormal proliferation of some cells of the intimate habit (endothelium in direct contact with the blood) and of the average one (formed by smooth muscle); the resulting thickening of the wall causes the arteriolar lumen to narrow. Hypertension and diabetes mellitus are important predisposing factors.
Calcific sclerosis of Mönckeberg
The calcific sclerosis of Mönckeberg is a particular type of arteriosclerosis, characterized by focal calcifications of the average tunic - generally on the middle and small caliber muscle arteries - up to the formation of bone tissue.
