Vascular pathology part 2 (atherosclerosis) Flashcards
Describe the differences between athero, arterio, & Monckberg medial calcific- sclerosis (SIMPLE definitions) i.e. size or vessel & type of blockage
Atherosclerosis = Plaques obstruct blood flow (large-med arteries)
Arteriosclerosis = Narrowed arterioles due to thickened vessel walls (small arteries)
Monckberg medial calcific sclerosis = non-obstructive calcification of the media of muscular (medium) arteries
Describe the make up of an intimal plaque in atherosclerosis
a necrotic lipid core (cholesterol) with a fibromuscular cap that undergoes dystrophic calcification
What are some risk factors for atherosclerosis?
(Modifiable/lifestyle):
- Hypertension
- Hypercholesterolemia
- Smoking
- Diabetes
(Nonmodifiable):
- Age
- Gender (males)
- Genetics
Describe the pathogenesis/formation of atherosclerotic plaques
- damaged endothelium leaks lipids into the intima
- Lipids are oxidized & eaten by macrophages turning them into foam cells (Fatty streaks)
- The inflammation & healing due to the damage leads to deposition of ECM & proliferation of smooth muscle which trap the foam cells forming plaques
- damaged endothelium leaks lipids into the intima
- Lipids are oxidized & eaten by macrophages turning them into foam cells (Fatty streaks)
- The inflammation & healing due to the damage leads to deposition of ECM & proliferation of smooth muscle which trap the foam cells forming plaques
This describes the process of which condition?
Atherosclerosis
Complications of atherosclerosis:
Atherosclerosis of popliteal artery leads to ______
Peripheral vascular disease
Complications of atherosclerosis:
Atherosclerosis of Coronary artery leads to ______
Angina
Complications of atherosclerosis:
Atherosclerosis of mesenteric arteries leads to ______
Ischemic bowel disease
Complications of atherosclerosis:
Atherosclerotic plaque rupture results in
MI (Coronary artery)
Stroke (Middle cerebral artery)
Complications of atherosclerosis:
Atherosclerotic plaque rupture with embolization results in
Atherosclerotic emboli characterized by crystals within the embolus
Complications of atherosclerosis:
Atherosclerosis leading to weakened vessel wall can result in
Aneurysm (abdominal aorta)
Describe the pathogenesis of hyaline arteriosclerosis (causes & what happens)
Caused by long-standing Benign hypertension or diabetes, it’s when proteins leak into the vessel wall causing it to thicken (very pink on microscopy)
What is a consequence of hyalin arteriosclerosis (leads to a major organ failure!)
The thickened arteriole has less caliber (smaller lumen) causing ischemia this results in:
- Glomerular scarring (arteriolonephrosclerosis) that can progress to renal failure
Describe the pathogenesis of hyperplastic arteriosclerosis (causes & what happens)
Due to malignant hypertension, it causes hyperplasia of the arterioles giving it an “onion skin” appearance & reduced vessel caliber (smaller lumen) causing ischemia:
- Can lead to fibrinoid necrosis of the vessel wall with hemorrhage (renal failure with “flea bitten” appearance)
Due to malignant hypertension, it causes hyperplasia of the arterioles giving it an “onion skin” appearance & reduced vessel caliber (smaller lumen) causing ischemia:
- Can lead to fibrinoid necrosis of the vessel wall with hemorrhage (renal failure with “flea bitten” appearance)
pathogenesis of hyperplastic arteriosclerosis
The thickened arteriole has less caliber (smaller lumen) causing ischemia this results in:
- Glomerular scarring (arteriolonephrosclerosis) that can progress to renal failure
consequence of hyalin arteriosclerosis
What’s the condition? (sclerosis type)
Hyperplastic arteriosclerosis
Describe the pathogenesis of Mockeberg medial calcification (what is it?)
Non-obstructive calcification of the media layer of muscular/medium sized arteries (Not clinically sig) you can see it on x-ray or mammography
What is the condition? (sclerosis type)
Mockeberg medial calcific sclerosis
What’s the condition
Mockeberg medial calcific sclerosis via mammogram
Describe what an aortic dissection is & what usually causes it & what’s the leading cause of death?
Usually due to Hypertension (older) or defective CT (i.e Marfan’s younger) which leads to an intimal tear with dissection through the media layer of the aorta the consequent leading COD is cardiac tamponade
Patient with long-standing hypertension presents with a sharp tearing pain that radiates to the back
1. What’s the likely diagnosis?
- Aortic dissection
Complications of aortic dissection:
- Pericardiac tamponade (Most common cause of death)
- Rupture with fatal hemorrhage
- Obstruction of branching arteries coronary or renal causing end organ ischemia
How does hypertension in older patients lead to aortic dissection?
The hypertension causes hyaline arteriosclerosis of the vasa vasorum which reduces blood flow to the media of the aorta (atrophy) weakening it eventually causing dissection
How do defects in CT in younger patients with Marfan’s/Elher-Danlos lead to aortic dissection?
Weak CT in the media of the aorta leads to cystic medial necrosis then eventually leading to dissection
Aortic dissection due to an inherited CT disorder (Marfan’s or Elher-Danlos)
Cystic medial necrosis
Aortic dissection due to hypertension more common in older patients
Hyaline arteriosclerosis of the vasa vasorum causing atrophy of the aortic media layer
Describe the most common cause of thoracic aneurysm
Atherosclerosis causes weakness in the aortic wall (a balloon-like aneurysm)
Describe what infection is classically seen in thoracic aneurysm
Patient with atherosclerosis classically has tertiary syphilis leading to endarteritis of the vasa vasorum (luminal narrowing of aorta) & atrophy giving aorta a tree bark app
What gives the aorta a tree bark appearance?
Atherosclerosis & syphilis infection combine to cause endarteritis of the vasa vasorum (luminal narrowing of aorta) & atrophy
What is a major complication of Thoracic aneurysm?
Dilation of the aortic valve root which causes aortic valve insufficiency
What are the additional complications (less common) of thoracic aneurysm?
- Compression of mediastinal structures like the airway or esophagus
- Thrombosis or embolism
Describe the causes of an aortic abdominal aneurysm
A balloon-like dilation of the abdominal aorta that usually arises below the renal arteries & above the aortic bifurcation
What is a major complication of an abdominal aortic aneurysm, what is the classical triad that presents.
Rupture is the major complication especially when the AA is over 5cm in diameter
Triad:
1. Hypotension
2. Pulsatile abdominal mass
3. Flank pain
What are the other complications of an abdominal aortic aneurysm
- Compression of nearby things i.e ureters
- Thrombosis or embolism
Atherosclerosis (slow) or Thrombus/embolus (fast) both lead to which type of damage?
Atrophy/infarction
Weakened blood vessel walls lead to which type of damage?
Dilation, Dissection, or Rupture
What conditions does atherosclerosis lead to?
- Ischemic heart disease (Acute MI & Angina Pectoris)
- Cerebral infarction (Stroke)
- Gangrene (lower extremities)
What are the 3 key characteristic lesions of atherosclerosis?
Any of these:
1. Atheroma
2. Atheromatous
3. Fibrofatty plaque
What are the arteries most commonly involved in atherosclerosis?
** Abdominal aorta
Coronary arteries
Popliteal arteries
Descending thoracic aorta
Internal carotid artery
Highest artery at risk of atherosclerosis
Abdominal aorta (anything over 5cm has a super high rupture risk)
Aldosterone is secreted via
Glomerulosa
Glomerulosa secretes
Aldosterone
Cortisol is secreted by
Fasciculata
Fasciculata secretes
Cortisol
Androgens (DHEA) are secreted via
Reticularis
Reticularis secretes
Androgens (DHEA)
An acute increase in BP (Malignant hypertension)
BV has an onion skin appearance
Hyperplastic arteriosclerosis
Describe the pathophysiology of hyperplastic arteriosclerosis
An acute increase in BP (Malignant hypertension) causes a proliferation in smooth muscle cells (onion skin app) this reduces blood flow causing renal failure with a flea bitten appearance
Increased protein deposition in BV walls can be due to
Hyalin arteriosclerosis due to
1. hypertension (more intraluminal pressure pushes proteins into wall)
2. Diabetes (Non enzymatic glycosylation of proteins makes them more permeable to leak into the BV wall)
Both processes result in glomerular scarring due to reduced blood flow & cause arterionephrosclerosisn
How can diabetes lead to hyalin arteriosclerosis?
Diabetes (Non enzymatic glycosylation of proteins makes them more permeable to leak into the BV wall)
How does tertiary syphilis lead to aortic aneurysm?
It causes inflammation of the vasovasorum (blood supply to the aorta) which causes ischemia & fibrosis of the aorta giving it a tree bark app
Signs hypotension
Pulsatile mass (abdomen)
Back/flank pain
Why is there a diastolic murmur associated with syphilitic induced aortic aneurysms
the aortic valve root dilates which causes aortic insufficiency (regurgitation) during diastole
Describe what superior vena cava syndrome is & what causes it?
It’s when the SVC gets compressed usually by a Pancoast (SCLC) or mediastinal lymphoma
Look out for increased jugular venous pressure
Hypertension with increased renin & aldosterone
We’ll see this in renal stenosis because the reduced blood flow will trick our kidneys into thinking we have low BP so renin & aldosterone will be increased
Usually one kidney is fine the other is fucked
Seen in
Atherosclerosis (Older)
Fibromyalgia (Younger)
How does hypertension cause aortic dissection?
Hypertension leads to arteriosclerosis of the vasa vasorum of the aorta which atrophies the tunica media leading to a weak spot where intimal tears can happen
Once torn the number one COD is pericardiac tamponade due to rupture of the aortic root!
Atherosclerosis
A 80 yr old male smoker presents to the clinic for flank pain. Upon examination hypotension & a pulsatile mass are noted. Judging by the size & history of discomfort the mass has likely been growing over time. What is the diagnosis?
Abdominal aortic aneurysm
