- Damage (such as high blood pressure) occurs to usually smooth endpthelium, white blood cells are attracted to site, mostly macrophages and lipids, they clump under the lining on the artery- forming fatty streaks
- They build up over time and harden to form a fibrious plaque- the atheroma
- Plaque cells die, causing surface to roughen, platelets dhere to damaged site and a blood clot forms
- Blood clot partially blocks lumen, restricting blood flow, causing blood pressure to increase
-It is a ballon like sweeling of the artery.
1. Atheroma plaquedamages and weakens arteries, narrowing them which in turn increases blood pressur.
2. When blood travels through the weakened artery at high presure, it may push the inner lining of the artery through the outer elastic layer.
3. It can burst, causing a haemorrhage.
1. Atheroma plaque can rupture the endothelium of an artery, damaging the artery wall and leaving a rough surface.
2. Platelets and fibrin (a protein) accumulate at site of damage and form a blood clot- thrombosis
3. Blood clot can cause complete bloackage of the artey, or can damage and block artery elsewhere.
4. Debris from rupture can cause another blood clot to form further down the artery.
Myocardial Infarction- Heart attack
1.Endothelium is damaged, white blood cells attatch to the area, and atheroma plaque begins to form, lipids deposit under the endothelium
2. Repair of damage causes thicker artery walls & rougher plaque surface, which results in more fatty materials to build up.
3. Blood clot forms, and gets stuck in narrowed lumen.
4. Blood flow stopeed by blood clot.
5. No Oxygen or glucose can get to patch of caridac muscle fed by that artery
6. Muscle cells die
7. Result in a heart attack, heart beat becomes uncoordinated