Pathology Of Cardiovascular Disease Flashcards
(18 cards)
What is a cardiovascular disease?
It’s the name given to any disease affecting the heart, blood vessels or blood pressure
What is cardiovascular disease caused by?
Atherosclerosis
What is atherosclerosis?
The accumulation of fatty material(consisting mainly of cholesterol, fibrous material and calcium) forming an atheroma or plaque beneath the endothelium
As the atheroma grows the artery thickens and loses its elasticity
The diameter of the lumen becomes reduced and blood flow becomes restricted resulting in increased blood pressure
What cardio vascular diseases is atherosclerosis the root cause of?(4)
Angina
Heart attack(myacardial infarction)
Stroke
Peripheral vascular disease
What is thrombosis?
The events leading to a myocardial infarction or stroke
What are the 6 stages of thrombosis?
Atheroma may rupture damaging the endothelium
The damage releases clotting factors that activate reactions resulting in the conversion of the enzyme prothrombin to its active form thrombin
Thrombin causes molecules of the plasma protein fibrinogen to form threads of fibrin
The fibrin threads form a mesh work that clots the blood, seals the wound and provides a scaffold for the formation of scar tissue
The formation of a clot(thrombus) is referred to as thrombosis
In some cases a thrombus can break loose- this is then called an embolus, which travels through the blood stream until it blocks a vessel
What does a thrombosis of the coronary artery lead to?
A myocardial infection/heart attack
What does thrombosis in an artery in the brain lead to?
A stroke
The cells are deprived of oxygen leading to death of the tissues
What is peripheral vascular disease?
It’s the narrowing of the arteries due to atherosclerosis, deep vein thrombosis or pulmonary embolism due to blood clots
These affect all areas of the body other than the heart and the brain
What does PVD most commonly affect?
The arteries of the legs are most commonly affected
Pain develops due to a limited supply of oxygen
What is a deep vein thrombosis(DVT)?
It’s a blood clots These affect that forms in a deep vein, most commonly the leg
This can break off and result in a pulmonary embolism in the lungs
What is cholesterol?
A type of lipid found in the cell membrane
It’s also used to make sex hormones-testosterone, oestrogen, progesterone
What is cholesterol synthesised by?
It’s synthesised by all cells, although 25% of total production takes place in the liver
What does a diet in high saturated fats or cholesterol cause?
An increase in cholesterol levels in the blood
What is the role of high density lipoproteins(HDL)?
They transport excess cholesterol from the body cells to the liver for elimination
This prevents the accumulation of cholesterol in the blood
What is the role of low density lipoproteins(LDL)?
They transport cholesterol to body cells.
Most cells have LDL receptors that take LDL into the cell where it releases cholesterol
Once a cell has sufficient cholesterol a negative feedback system inhibits the synthesis of new LDL receptors and LDL circulates in the blood where it may deposit cholesterol in the arteries forming atheromas
What will a higher ratio of HDL to LDL result in?
Lower blood cholesterol and reduced chance of atherosclerosis
(Better for health)
How can you increase your HDL levels?
Regular physical activity tends to raise HDL levels
Reducing your total fat intake by doing diet changes, changing intake of saturated fats to unsaturated fats
Using drugs called STATINS to reduce blood cholesterol
Statins function by inhibiting the synthesis of cholesterol by liver cells
