CVPR Week 4: Atherosclerosis Flashcards
What is arteriosclerosis?
hardening and thickening of artery walls
Types of arteriosclerosis
3 listed
- Atherosclerosis
- Medial calcification
- Arteriolarsclerosis
What is atherosclerosis?
- medium to large arteries
- defined by intimal atheromas
What is medial calcification?
consequence of age
Calcium depositis in the media of the blood vessels
What is arteriolarsclerosis?
arteriosclerosis of small blood vessels less than 0.3 mm
2 different types
- hyperplastic intimal thickening
- Hyalin: acellular thickening (shown in this histologic section)
Atherosclerosis is defined by?
Intimal atheromas
What are Intimal atheromas?
a fatty collection within the blood vessel intima
Medial sclerosis AKA
Monckeberg’s sclerosis
What is this?
medial sclerosis
has calcium deposits in the muscular media of the blood vessel
What is this?
hyalin type arteriolarsclerosis
where there is acellular thickening in the intima of the very small blood vessel secondary to endothelial dysfunction
What is this?
Hyperplastic type Arteriolarsclerosis
where the intima thickening due to intima hyperplasia
hyalin type arteriolarsclerosis is associated with?
essential or common type HTN
Hyperplastic type Arteriolarsclerosis is associated with
malignant HTN or extremely high BPs
Atherosclerosis vessels that can be affected?
8 listed
Identify
What is this a depiction of?
gross view of atherosclerosis in the abdominal aorta, these brown spots are all ulcerating atherosclerotic plaques within the aorta
microscopic pathophysiology of atherosclerosis
8 listed
defined by intimal plaques
muscular media changes
- loss of smooth muscle cells
- increase of collagen fibers
- increase of ground substance
Adventitia changes
- fibrous thickening
- mild inflammation
What is this
atherosclerotic intimal plaque
Identify
How are atheromatous plaques initiated and formed
- atherosclerotic plaques are thought to arise from an initial endothelial dysfunction or injury
- the risk factors explain how the endothelial injury or dysfunction can arise such as high BP
- the endothelial dysfunction or injury allow monocytes migrate to the intima and become macrophages
- leukocytes and monocytes recruit smooth muscle cells from the media layer and these move into the intima and form a fibrous cap
What is this?
atherosclerotic plaque and fibrous cap
What is this?
lipids in atherosclerotic plaque and fibrous cap
what is the weakest part of the atherosclerotic plaque
the shoulder of the fibrous cap… this is important because
Atherosclerosis risk factors
10 listed
unchangeable atherosclerosis risk factors
- age
- sex
- genetics
Major reversible atherosclerosis risk factors
4 listed
- smoking
- diabetes
- HTN
- HLD
Minor reversible atherosclerosis risk factors
3 listed
- Obesity
- lifestyle
- personality
Pathogenesis of atherosclerosis
Clinical effects of atherosclerosis
4 listed
- arterial narrowing - organ ischemia or injury
- Thrombus if the plaque ruptures
- embolize if the plaque ruptures
- aneurysm formation from the weakening of blood vessels
Arterial narrowing causes
3 listed
shoulder regions are prone to rupture
Thrombosis cause by?
acute changes in plaque
- erosion or ulceration
- plaque hemorrhage
- plaque rupture
What is this?
arterial narrowing due to
- shown is atherosclerotic plaque
- huge Calcium deposit
- and the hemorrhage of into atheroma
Plaques most vulnerable to rupture
3 listed
- moderate luminal narrowing like 50% stenosis
- Lipid rich center
- Thin fibrous cap
What is this?
Thrombus in blood vessel from ruptured plaque
call lines of Zohn which are alternating fibrin and RBCs
What is this?
Embolism initiation, origin and destinations?
- rupture or erosion of plaque
- most from the aorta
- most go to kidneys, pancreas and spleen or the lower limbs and cause dry gangrene
What is this?
dry gangrene from an embolus
What is an aneurysm?
- an excessive localized enlargement of an artery caused by a weakening of the artery wall.
- Abnormal dilation of a blood vessel
Aneurysm Types
2 listed
- Atherosclerotic
- Dissecting
What is this?
gross histological image of an atherosclerotic aneurysm of the abdominal aorta
Atherosclerotic aneurysm common location
- abdominal aorta below the renal arteries
- Iliac arteries
Atherosclerotic aneurysm common in?
- Men > women
- >60 years old
Atherosclerotic aneurysm
Atherosclerotic aneurysm size?
becomes clinically significant when > 5cm in diameter
Dissecting aneurysm risk factors
- HTN
- Genetics: connective tissue disease such as (Marfan Syndrome)
Dissecting aneurysm types
- HTN or genetic such as marfans
- Both types have cystic medial degeneration
Dissecting aneurysm location
commonly starts in the arch of the aorta
What is this?
Aortic dissection gross histological image
What is this?
- outside relatively normal muscularis media
- inside cystic medial degeneration
- starts of an aneurysm
Marfan Syndrome Cause
Autosomal dominant mutation in FBN1 gene (Fibrillin-1 gene)
Marfan Syndrome epidemiology
1 in 5000
25% are new mutations
FBN1 description & pathology
3 listed
- Marfans Syndrome
- is an important component of the ECM
- normally affects these organ systems cardiovascular, ocular and skeletal system
- it provides scaffolding for elastic fibers in medium and large blood vessels
Marfan’s Syndrome diagnostic criteria
What is this?
- Marfan’s Syndrome
- Pectis caranadum (pigeon-beaked chest)
What is this?
- Marfan’s Syndrome
- Pectis excavitum (cavitated chest)
Hand signs of Marfan’s Syndrome
Marfan’s torso
Scoliosis of >20* is characteristic of Marfan’s Syndrome
What is this?
hyper or hypo elbow extension is common in Marfans
What is this?
Pes planus (flat feet) common in Marfans
Major skeletal system features of Marfan’s Syndrome
7 listed
What is this?
ectopia lentis (lense dislocation) is common in marfans
What is this?
Aortic root dilation in Marfan’s
What is this?
aortic dissection from a dilated aortic root which is common in Marfan’s
Major cardiovascular features of Marfans
Minor pulmonary features of Marfans
High risk for spontaneous pneumothorax absence of vascular markings on the left in this
apical blebs
Skin and integument features of Marfans
- lumbosacral dural cysts
- this is an expansion in the lumbosacral area
Marfan’s family history
2 listed
Major part of the diagnostic criteria
Pathology of Marfans
- Fibrillin-1 forms microfibers in the cardiovascular system and connective tissue
- makes up microfibrils in the ECM and helps to form the scaffolding for the elastic fibers
- Elastic fibers are one the main contributors of integrity to blood vessels
Fibrillin-1 mutations
Main coronary arteries
3 listed
Left coronary artery
Right coronary artery
circu?
Identify
Myocardial ischemia is a deficit in?
Amount of coronary blood flow
Causes of defect in amount of coronary flow
- Size/narrowing of coronary arteries
- hypotension
- development of the collateral circulation
- arrhythmias
Defects that can cause myocardial oxygen requirements
- Anemia
- Exercise/Excitement/fever/hyperthyroidism
MI concerns and contributing factors
6 listed
Identify grade of occlusion of coronary artery
grade 0
Identify grade of occlusion of coronary artery
3 listed
- grade 1
- 25% occlusion
- minimal occlusion
Identify grade of occlusion of coronary artery
4 listed
- grade 2
- 50% occlusion
- highest risk for plaque rupture
- Mild occlusion
Identify grade of occlusion of coronary artery
3 listed
- Grade 3
- 75% occlusion
- moderate occlusion
Identify grade of occlusion of coronary artery
3 listed
- Grade 4
- 90% occlusion
- marked occlusion
Identify grade of occlusion of coronary artery
- Grade 6 complete occlusion
- Complete occlusion
What is this?
moderate occlusion that ruptured grade 3 occlusion rupture at shoulder region
Main coronary arteries and areas perfused
3 listed
LAD: Anterior wall, apex, septum
Right Coronary: posterior base and posterior septum
Left circumflex: Lateral wall
What is this?
coronary artery thrombus
importance and consequences of developing collateral circulation
collaterals developed between right and left coronary artery collateral problem is if you get a thrombus in the right you may also get ischemia on the other side as well
Infract size and location
- the more proximal the infarct is then more likely to cause a large territory infarct
- if distal it is much more likely to cause a small area infarct
- also dependent upon the adequacy of collateral circulation
Recent thrombus and larger coronary artery typically
transmural large-territory infarct
Thrombus of an already narrowed artery typically
subendocardial infarct
What is this?
?
Sequela of infarct
5 listed
- death from arryththmia or CHF
- if survive
- Healing
- can result in an aneurysm commonly seen in apex and commonly involve LAD
- myocardial rupture can occur (most vulnerable 3-7 day window)
- postmyocardial syndrome (Dressler’s Syndrome)
Healing sequelae of MI
- first 12 hours neutrophils grow in density 1-3 days
- 3-7 days clean-up phase macrophages clean up dead neutrophils and myocytes
- 7-14 days repairative phase deposition of granulation tissue
- 2-8 weeks deposition of scar tissue
Most common postmyocardial syndrome
Dressler’s Syndrome
Dressler’s Syndrome description
- an immune-mediated event after underogoing a MI
- occurs 10-14 days after large-territory MI
- main manifestation (pericarditis or inflammation of pericardium)
- pericarditis can be Dx by EKG and signs and symptoms
What is this?
- most people that suffer cardiac sudden death don’t present with coronary artery thrombi
- they instead have multiple severe stenotic atherosclerotic lesions of the coronary arteries which precipitated an MI from which they died in minutes
What is this?
- large apical aneurysms following a large-territory MI
- can create thrombi which can cause end-organ damage
what is this?
large intramural thrombus in the left ventricle in an area of thrombus
thrombi develop here because aneurysms are akinetic and blood pools within the aneurysms
Infarct healing
Sudden Cardiac Death
Summary
