Vascular Disease Flashcards
What are the three general forms of arteriosclerosis?
- Atherosclerosis
- Monckeberg’s Medial Calcific Sclerosis
- HTN-induced arteriosclerosis
Atherosclerosis predominantly involves which arteries?
Elastic arteries (aorta, carotids, iliacs) Muscular arteries (popliteal, coronary, renal, mesenteric)
Modifiable Causes of Atherosclerosis
Hypertension Hyperlipidemia Cigarette Smoking Diabetes Inflammation
Non-Modifiable Causes of Atherosclerosis
Age
Male Gender
Family History
Genetics
Atherosclerosis is a chronic inflammatory response of the arterial wall to…
Endothelial injury
Describe the basic structure of an atheroma
Fibrous cap and a necrotic core formed int the intima between the IEL and the endothelium
What is the fibrous cap of an atheroma composed of?
Collagen, smooth muscle, foam cells, proteoglycans, elastin, ECM
What is the necrotic core of an atheroma composed of?
Cell debris, cholesterol (LDL), macrophages (foam cells), calcium deposition
What are some complications of atheromatous plaques?
Rupture/ulceration/erosion Emboli Hemorrhage Weakened media leading to aneurysm Calcification Lumen occlusion Thrombosus
What is Monckeberg’s Medial Calcific Sclerosis
Calcium deposition in the media, leading to hardening of the artery. Typically occurs in medium sized arteries
Does Monckeberg’s Medial Calcific Sclerosis cause any pathology?
No obstruction of the lumen
List the two types of HTN-induced arteriosclerosis
Hyaline arteriosclerosis
Hyperplastic arteriosclerosis
Hyaline Arteriosclerosis
What causes it? What happens? How does it appear on histology?
Longstanding HTN causing hemodynamic stress on the blood vessels. Allows plasma proteins to leak into the blood vessel walls. Give the vessels a PINK appearance. Can lead to narrowing of the lumen, which could cause ischemic injuries over time
Hyperplastic Arteriosclerosis
What causes it? What is the response? What is the appearance on histology?
Caused by severe acute blood pressure elevations, leading to endothelial injury.
Smooth muscle responds by duplicating and replicating, leading to luminal narrowing. Onion skin appearance on histology.
List some reasons for the formation of aneurysms
Atherosclerosis - weakening of the wall and less smooth muscle can lead to wall dilatation
Genetic abnormalities (Marfan’s syndrome - defective fibrillin; Ehlers Danlos Syndrome - defective type III collagen)
Altered balance of collagen deposition and synthesis (inflammation)
Trauma
What is Cystic Medial Degeneration?
Degeneration of elastin, leading to areas devoid of smooth muscle and elastin
What is the major cause of AAAs?
Atherosclerosis
Compression of the media leads to degeneration and necrosis, weakening the vessel wall and leading to an aneurysm
Where are AAAs located?
Infrarenal
Above aortic bifurcation
What are the classic clinical findings of AAA? Who is likely to get it?
Male smokers over the age of 50
Pulsatile abdominal mass
Complications of AAA
Compression of other structures Obstruction Embolism Rupture (think about treatment to avoid rupture when it grows above 5 cm)
Which STD could cause vascular disease later in life?
Syphilis.
In tertiary syphilis, the vaso vasorum is injured and the aortic wall becomes ischemic. Has a tree bark appearance and may dilate due to weakening of the wall
Aortic Dissection
Describe the main 3 classifications
DeBakey I - involving proximal and distal aorta
DeBakey II - involving proximal aorta only
DeBakey III - involving distal aorta only
What is the biggest risk factor for aortic dissection?
HTN
Causes narrowing of the lumen of the vaso vasorum and degenerative changes of the media. We don’t know exactly what causes the intimal tear leading to aortic dissection.
Connective tissue disorders and bicuspid aortic valves are also commonly associated with dissection.
What does aortic dissection commonly present as?
Stabbing pain in the chest
Radiates to the back
Treatment of Aortic Dissections
Requires surgery if dissection involves the proximal aorta. If DeBakey III, then need to control HTN to prevent further endothelial injury
