RCQ CH 3 Flashcards
(47 cards)
name of the outer layer of coronary artery
adventitia
function of adventitia
collagenous fibers that provide basic support structure
houses vasa vasorum
name of the middle layer of coronary artery
media
composition of the media
layers of smooth muscle cells that are separated by an elastic membrane
what is the lamina
elastic membrane that separates the smooth muscle cells in the media
function of the media
luminal diameter control
-vasoconstriction/dilation
smooth muscle cells in the media do this as well as constricting/dilating
synthesize:
collagen
elastin
glycosaminoglycans
in response to physical/chemical stimuli
name of the inner layer of coronary arteries
intima
composition of intima
endothelial layer
basement membrane
isolated smooth muscle cells
collagen/elastin fibers
the arterial endothelium is _____ and this is important because
selectively permeable to LDLs
- lipoproteins and fibrinogen are likely to accumulate there
atherosclerosis
progressive hardening and narrowing of the coronary, cerebral and peripheral arteries
atherosis initial sign
fatty streak
- deposits of lipid laden macrophages and smooth muscle cells
what are foam cells
clusters of monocytes between endothelial cells that accumulate lipids
what happens in an intima-based lesion? what is the result of that?
underlying CT is exposed to circulation
platelets aggregate and a thrombus forms
what causes end-organ damage
not pure atherosis alone, will need sclerosis to cause end damage
sclerosis
reduction of blood vessel compliance due to increased collagen and decreased elastin
what causes sclerosis
subendothelial structures exposed to thrombus formation
encrustation
formation of fibrous cap over advanced plaques in the endothelial lining
role of platelet derived growth factor in sclerosis
Stimulates replication of CT cells in the intima
acts as a chemoattractant
—attracts smooth muscle cells to migrate from the media to intima
differences between variant and stable angina
Associated with the ST segment elevation instead of depression
Occurs at rest rather than activity
Not associated with any preceding increase in myocardial oxygen demand
Those with variant angina will be able to perform high levels of work later in the day without symptoms, those with unstable angina will not be able to
similarities of variant and stable angina
nitroglycerin/vasodilators aid symptoms
proposed origin of variant angina
Vasospastic nonlesion that will constrict instead of relaxing when stimulated
hyperreactivity of coronary smooth muscle due to a reduction in the release of nitric oxide
characteristics of chronic stable angina
Predictable mode of symptom provocation (certain level of myocardial oxygen demand)
Reduction of intensity or nitroglycerin
Slight variability in tolerance of activity (good/bad days)
characteristics of sudden cardiac death
- 40-50% of patients –
related to atherosclerosis
tachycardia
ventricular fibrillation
cessation of cardiac output
AED within 10 min is only hope
