Mönckeberg's arteriosclerosis
Definition
Medial calcific sclerosis a form of arteriosclerosis in which extensive calcium deposits are found
in the tunica media of the artery with little obstruction of the lumen.
Also called medial arteriosclerosis. and Mönckeberg's arteriosclerosis
Signs and symptoms
Typically, Monckeberg’s arteriosclerosis is not associated with symptoms unless complicated by atherosclerosis, calciphylaxis, or accompanied by some other disease However presence of Monckeberg’s arteriosclerosis is associated with poorer prognosi. This is probably due to vascular calcification causing increased arterial stiffness, increased pulse pressure and resulting in exaggerated damage to the heart and kidneys.
Diagnosis
Often Monckeberg’s arteriosclerosis is discovered as an incidental finding in an X ray radiograph; in autopsy; or in association with investigation of some other disease, such as diabetes mellitus or chronic kidney disease.
Typically calcification is observed in the arteries of the upper and
lower limb although it has been seen in numerous other medium size
arteries
In the radial or ulnar arteries it can cause "pipestem" arteries, which
present as a bounding pulse at the end of the calcific zone. It may
also result in "pulselessness." Epidemiological studies have used the
ratio of ankle to brachial blood pressure (ankle brachial pressure index,
ABPI or ABI) as an indicator of arterial calcification with ABPI
>1.3 to >1.5 being used as a diagnostic criterion depending on the
study
Cause
Minor degrees of calcification of the cardiovascular system are common in elderly people and the prevalence of vascular calcification is increased by some diseases , Vascular calcification results from the deposition of calcium phosphate crystals (hydroxyapatite)
as a consequence of disordered calcium phosphate regulation in the
blood vessel. Hydroxyapatite is secreted in vesicles that bleb out from
vascular smooth muscle cells or pericytes in the arterial wall. The mechanism of vascular calcification is not fully understood, but
probably involves a phenotypic change in the vascular smooth muscle
cells in the wall with activation of bone-forming programs. Numerous
regulators of calcification such as osteopontin, osteoprotegerin, matrix
gla protein and fetuin-A, receptor activator of NF-kappa-B, receptor
activator of NF-kappa-B ligand and tumour necrosis factor (TNF)-related
apoptosis-induceing ligand protein have been implicated in this process.
It is unclear whether Monckeberg's arteriosclerosis is a distinct
entity or forms part of a spectrum of vascular calcification that
includes atherosclerosis and calcification in the inner layer of the
artery wall (tunica intima), calcification of the internal elastic lamina, calcification of cardiac valves and widespread soft tissue calcification.
The existence of Monckeberg's arteriosclerosis has been disputed and it
has been proposed that it is a part of a continuum of atherosclerotic
disease: the majority of atherosclerotic plaques contain some calcium deposits and calcification of the internal elastic lamina is common in pathological specimens labelled as Monckeberg's arteriosclerosis.
However studies in animals suggest that a predominantly medial pattern
of vascular calcification reflects different underlying mechanisms of
disease,and despite involvement of the internal elastic lamina, evidence of inflammation is rare in Monckeberg's arteriosclerosis.
Reference
"Mönckeberg arteriosclerosis" at Dorland's Medical DictionaryCategory: M


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