Cardiovascular Pathology Flashcards
what is arteriosclerosis
arteriosclerosis is the hardening and thickening of the wall of the arteries, occurs typically in old age and can happen due to inflammation
what is atherosclerosis
happens due to the deposition of cholesterol in the blood vessel wall
what is the most important risk factor in atherosclerosis
hyperlipidemia
how does an atheroma occur
there is chronic inflammation due to cholesterol deposition, there will also be a healing response but there is actually no healing and it is these processes that result in atheroma
what is the vascular pathology that happens due to atherosclerosis
either stenosis or obstruction or weakening of the walls leading to dilation/rupture
what are the non-modifiable risk factors for atherosclerosis
age
gender
genes
what is the gene that can affect risk factors for atherosclerosis
family hypercholesterolemia is mutation of the LDL receptor gene
what happens if there is a mutation of the LDL receptor gene
there is not as much cholesterol uptake meaning there is more circulating cholesterol which puts the person at higher risk of atherosclerosis from a young age
any lifestyle factors will also increase the risk
describe endothelial cells in the basal state
normal when BP is within a normal range
cells will be smooth and non adhesive
what factors can cause endothelial cells to change
lifestyle factors - smoke, lipid products etc
describe endothelial cells in the activated state
turbulent flow
change in the cells due to cytokine productions
encouragement of pro coagulation
can produce cytokines and growth factors which can cause a lot of different changes in the blood vessel
what are the two phases in the formation of an atheroma
chronic inflammatory phase
healing response phase
what is the chronic inflammatory response due to in the chronic inflammatory phase
response to lipoproteins
what happens in the chronic inflammation phase
endothelial cells change surface cell receptors and become more permeable to lipids
change cell adhesion molecules for monocytes so attach to endothelium and move into blood vessel walls
what are the monocytes in the chronic inflammatory phase
monocytes include macrophages and t cells
what level of the blood vessel wall do the lipids pass into
intima - first level
why do the macrophages do
they ingest lipid that is deposited into the wall and become big and pale colored - foam cells
what happens to the lipid that the macrophages ingest
it stays in the macrophages until death
as the macrophages die the lipid returns into the circulation
what is the healing response phase
there is proliferation of smooth muscle cells
fibrous tissue formation
growth factor production
fibro fatty plaque is formed with a central mass of lipid and necrotic tissue
neovascularisation may be seen at the periphery of the plaque
a hemorrhage can occur in the plaque
calcification of the lipid and necrotic tissue may sometimes occur
describe the 5 stages of the formation of an atheroma
1, chronic endothelial cell injury (may be genetic mutation, inherited, hypertension)
- permeability increases, lipid deposited in the intimal layers
- macrophages move in and become foam cells. fatty streaks form
- smooth muscle proliferation. macrophages produce IL-1 which activates T-cells. more cytokines, chemokine, ROS activate more inflammatory cells
- (healing phase). fibrous tissue formation, over the lipid and a fibre fatty atheroma is formed (plaque). dystrophic calcification may occur at late stages.
what are the effects of atherosclerosis
decreased blood supply to tissue/organ (ischemia)
complete occlusion of the blood vessel leads to infarction
thrombosis
embolism
how does thrombosis occur because of atherosclerosis
there is release of thrombogenic factors
coagulative process occurs
formation of blood cut on top of atheroma and completely cuts off blood supply
what happens in peripheral vascular disease
you can get ischemia which results in claudication
ischemia can cause gangrene (form of coagulative necrosis) and infection
what is an aneurysm
abnormal dilation
where can aneurysm occur
blood vessel or in the cardiac wall
what are the causes of aneurysm
can be factors such as developmental, degenerative or traumatic
what is an abdominal aortic aneurysm
commonest and results from atherosclerosis
how does aneurysm play a role in peripheral vascular disease
it is associated with macrophages in the blood vessel wall
MMP can breakdown fibres in the blood vessel wall widening it and can weaken the structure and this can happen in the cardiac wall as well
what are acute coronary conditions
angina pectoris
myocardial infarction
what happens in myocardial infection
loss of blood supply, oxygen nutrients ect
results in coagulation necrosis of the myocardial muscle
it cannot survive on anaerobic respiration
healing is by granulation tissue and this affects heart function as the new tissue does not have the same function as the myocardial tissue
what happens to the cells in coagulation necrosis
cell retain outline so can be identified cytoplasm becomes darker remains of nuclei striations lost neutrophils come into the tissue first and then macrophages come after granulation tissue is formed
how is granulation tissue formed
fibroblasts produce collagen
capillaries are formed to bring blood to rapidly dividing cells
gradually overtime the number of blood vessels decrease, inflammation decreases
what does congestive heart failure follow from
usually follows on from ischemic heart disease, hypertension or valvular heart disease
what does congestive heart failure result in
ventricular hypertrophy
edema
chronic venous congestion of lungs and liver
what is the pathophysiology of congestive heart failure
hypertrophy of myocyte (adaptation)
capillaries do not increase in number
increased metabolic demands can result in ischemia and this causes injury to the myocyte
the end result can be necrosis and heart failure
what are the different types of tumors of the blood vessels
hamartomas
kaposi sarcoma
angiosarcoma: rare, aggressive
what is a hemangioma
it is a hartoma
rapid growth during the first weeks of life
usually regress over the first 10 years
what are vascular malformations
common
present at birth and persist during life
may be more noticeable in the elderly as the mucosa becomes thinner
what are the types of vascular malformations
capillary
cavernous
sturge weber syndrome
what happens in sturge weber syndrome
the haemangion extend to the midline and the distribution follow the distribution of nerves
this person may have extensive haemangioma intra orally and they may also have hemangioma in their jaw bone - must be treated for invasive dentistry in hospital
what is the cause of kaposi sarcoma
herpes virus 8
what is kaposi sarcoma
multi-focal low grade sarcoma of lymphatics and blood vessels
what is the common patient with oral KS
HIV infected patients
what is the importance of kaposi sarcoma
with treatment, 90% of cases are controlled
the virus has the ability to produce this malignancy in those who are immune suppressed
what does immune deficiency have a role in
carcinogenesis
how common are cardiac tumors
rare
what are the benign cardiac tumors
myxoma
lipoma
what are the malignant cardiac tumors
angiosarcoma
what is valvular heart disease
congenital or acquired
if valvular heart disease is acquired what is it most likely because of
a result of other cardiac diseases such as ventricular hypertrophy
what can valvular heart disease pathology result in
stenosis (injury to valve)
insufficiency - closing of the valve will be impaired so there will be a regurgitation of blood back into the chamber
vegetations - growths of lumps upon cusps of valve
what is calcific aortic stenosis
commonest of all valvular conditions
dystrophic calcium deposits happen as a result of tissue inflammation
results in the narrowing of the valvular orifice and makes the valve stiff and hard to open
may require valve replacement
what should be kept in mind if a patient has a valve replacement
that they are on anticoagulants
what is rheumatic heart disease
results from rheumatic fever
mainly affects valves
host immune reaction against streptococcus A antigens that cross react with host proteins
damage is caused by a combination of type 2 and type 4 reactions
describe the pathology of rheatmic heart disease
inflammation of endocardium and valves results in fibroid necrosis
vegetations formed along the lines of closure
thickening and fusion results in the calcification of valves
can result in aortic dilation, atrial fibrillation, thrombi formed on the wall of the atrium
susceptible to developing infective endocarditis
what is infective endocarditis
microbial infection of heart valves
damaged or prosthetic valves are particaruly susceptible
oral pathogens may be implicated: s. viridens and s. aureus
vegetations formed on cusps contain fibrin, inflammatory cells, and infective pathogens
can cause infective emboli
