Atheroma's, Thrombosis, Embolism Flashcards
What is an atheroma?
- Intimal lesion (beneath endothelium)
- Protrudes into the vessel wall
- Necrotic centre - fat and debris
- with a Fibrous Cap
What makes up the necrotic centre of an atheroma?
Cholesterol and cholesterol esters
Foam cells
Calcium
Cell debris
What makes up a fibrous cap?
SMCs
Collagen
Macrophages …
Where do atheroma’s commonly form? (6)
¥ Bifurcations (sites of turbulent flow) ¥ Abdominal aorta ¥ Coronary arteries ¥ Popliteal arteries ¥ Carotid vessels ¥ Circle of Willis
What are C-reactive proteins?
proteins produced by the liver in response to inflammation influx
Males or females are more predisposed to atheromas?
Males
It is thought that atheroma develop in response to…?
Vessel wall injury
What are the 5 steps of the response-to-injury hypothesis?
- Chronic endothelial injury
- Vascular permability & Endothelial dysfunction
- Macrophage activation and Smooth Muscle Cell activation
- Macrophages and Smooth Muscle cells engulf
- Cap formation
Name 4 common complications of atheromas
¥ Rupture, ulceration or erosion
¥ Haemorrhage out of plaque- blood loss and hypotension
¥ Atheroembolism- formation of thrombus
¥ Aneurysm formation- dislodge and embolise
What is a Thrombus?
A blood clot lodged onto a vessel wall
What is the mechanism of arterial thrombus’ formation?
Forms as a result of rupture of atherosclerotic plaque
Common locations of arterial thrombus’
Left chamber of heart, arteries
What is the mechanism of venous thrombus’?
Combination of the following :
Endothelial injury, hypercoagulability, abnormal blood flow
What are the factors of Virchow’s triad?
- endothelial injury
- hyper coagulability
- abnormal blood flow
What is claudication?
pain caused by too little blood flow common during exercise
3 common arterial thrombus diseases
- Acute coronary syndrome
2. Ischaemic stoke 3. Claudication
Common diseases associated with Venous thrombus’
DVT and Pulmonary embolism
Main composition of venous thrombus
Fibrin
Main composition of arterial thromboses
Platelet
Examples of Antplatelet agents
clopidogrel
Examples of Anticoagulants
heparin and warfarin
Homeostatic plug define
A blood clot forms at the site of vascular injury
Platelets are not involved in clot or thrombus formation?
Clot formation
Colour of venous thromboses
Red
Colour of arterial thromboses
Pale
Embolism
- Mass of material in vascular system
* Able to lodge in vessel and block it
Can be solid, liquid or gas and can cause harm to circulatory system
Embolism
