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Atherosclerosis and Thrombus Formation
Plaque Fissuring and Formation
 The
mechanisms of plaque destabilization (fissuring and rupture,
followed by thrombus formation) are not fully understood.
Study of plaques in the coronary arteries that have undergone
fissuring indicate that the majority are composed of eccentrically
situated lipids (i.e., located in an area where the vessel
bifurcates) that do not have an internal lattice of collagen
supporting the cap of the plaque.
The vulnerability of such a structure to fissuring
appears to be related to circumferential stress on the plaque
cap in systole, as well as infiltration of the cap tissue
with foam cells (with reduction of total collagen content
and a concomitant fall in tensile strength) [Davis MJ, 1994].
It is unclear whether foam cells weaken the tissue by passively
distorting the spatial arrangement of the connective tissue
matrix or by actively destroying connective tissue matrix
protein by lytic mechanisms.
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Stroke Education
