2.7 Flashcards
Cardiovascular disease is
Any disease that affects the heart or circulatory system. EG angina, heart attack, stroke
What is atherosclerosis
The blockage and hardening of arteries caused by formation of an atheroma under the endothelium of the artery. This blockage causes narrowing of lumen, making heart have to work harder to circulate blood
What is atheroma made up of
The atheroma that starts to narrow the lumen is made up of fat calcium cholesterol and other fibrous material found in blood.
Effects of narrowing lumen on artery
An increase in blood pressure as heart works harder to supply same area with oxygen. Loses elasticity and becomes harder.
Causes of atherosclerosis
High blood pressure
Carbon monoxide in cigarettes
Diabetes
High blood cholesterol
High fat diet
Low exercise regime
What is clot formed by atheroma increasing in size
Thrombus.
What is thrombus
A clot formed by atheroma increasing in size and blood finding it impossible to pass through the lumen.
Process of atherosclerosis
Damage to endothelium of artery causes accumulation of calcium, fat, cholesterol under the endothelium - atheroma
As atheroma enlarges into the smooth muscle wall, the walls became brittle and the artery hardens.
Atheroma continues to grow and reduces size of lumen
Blood pressure increases as heart works harder to pass blood through small lumen
Process of thrombus formation
When endothelium is damaged platelets in the blood sense this and release clotting factors
Clotting factors activate a dormant enzyme called prothrombin, this activation causes prothrombin to become thrombin
Thrombin starts converting a soluble protein in blood called fibrinogen into sticky, threaded insoluble compound called fibrin
Sticky fibrin threads knit together, catching RBCs and WBCs. This forms a clot. If inside artery it is called a thrombus.
What issues does thrombus bring
A thrombus blocking an artery prevents oxygen and nutrients getting to the tissue that the vessel supplies. This can result in tissue death.
Thrombus can also cause an embolus of blood pressure around thrombus get’s high enough, this can cause myocardial infection and stroke
What is a myocardial infarction
Also known as a heart attack. An embolus forms a clot in a coronary artery. Oxygen is cut off from the muscle, heart can no longer beat in correct rhythm
What is a stroke
If an embolus travels and blocks artery in brain, stroke can occur. Brain needs oxygen and it’s cut off if embolus. Lack of oxygen means brain tissue dies.
What is peripheral vascular disease
The narrowing of arteries outside of the heart and brain. Atherosclerosis is the cause of this disease.
What is a pulmonary embolism
A blood clot in the arteries of the lungs. Restricts oxygen intake and can cause other clots to form.
Deep vein thrombosis
A blood clot (thrombus) in a vein (usually leg)
