Atheroma and Complications Flashcards
Arteriolosclerosis
Thickening and hardening of an arteriole wall
Atherosclerosis vs Arteriosclerosis
Arteriosclerosis is the thickening and hardening of an artery wall while atherosclerosis is arterioscleosis due to an atheroma
Most common causes of arteriosclerosis in large & medium arteries vs small arteries & arterioles
Atheroma is the most common cause of arteriosclerosis in LARGE & MEDIUM arteries
High BP is the most common cause of thickening/hardening of walls of small arteries & arterioles
Changes that occur in hypertensive arteriosclerosis
Hypertrophy of Media
Fibroblastic thickening of intima
Elastic lamina reduplication
Change that occurs in hypertensive arteriolosclerosis
Replacement of wall structures by amorphus hyaline material
Consequences of hypertensive vascular changes
Reduction of vessel lumen leads to reduced flow and thus ischaemia in supplied tissue
Increased rigidity of vessel wall leads to loss of elasticity and contractility and so the vessels lose response to normal vessel control agents
Atheroma and which vessel layers are affected
Disease of large and medium arteries that only occurs in high BP systems (ie not venous system)
Disease of tunica intima initially but later affects tunica media
What does an expansion of tunica intima during atheroma lead to
Reduction of lumen size and reduced blood flow/oxygenation of tissue
Consequence of ulceration during atheromas
Fatty tissue is exposed and a thrombus can be formed as the nasty components are exposed (Vessel occlusion)
Consequence of muscle fibre replacement during atheroma
Elasticity is lost and the vessel can undergo thinning & stretching, leading to an aneurysm
What can coronary artery atheroma lead to (besides MI)
Angina
What condition is predisposed when a patient gets atheromas
Thrombosis as a damaged and ulcerated endothelium may lead to thrombus formation
Aneurysm and what is its most common cause
Abnormal permanent focal dilatation of an artery
Most common type is secondary to atherosclerosis
How might damage caused to the tunica media by an atheroma lead to an aneurysm
Enlarging initial atheroma plaque leads to media atrophy and replacement of muscle/elastic fibres with collagen
Collagen is strong but neither contractile nor capable of elastic recoil; thus each systolic pulse leads to the stretching and thinning of arteries, particularly when BP is elevated
Three main types of aneurysms
**Blood leaks around in dissecting
What type of aneurysm is this
Abdominal aneurysm (abdominal aorta)
