Question

Me. K. is a 57- year - old man who consulted his physician after noticing marked leg pain while playing golf. He had previously noticed increasing fatigue and discomfort in his legs associated with moderate exercise. when sitting for extended periods with legs became red, and sometimes his feet felt numb. His history indicated he smokes cigarettes and is chronically overweight. His blood cholesterol and other lipid levels are abnormal, and his physician suspects peripheral atherosclerosis as the cause of his discomfort.

discussion questions

1. Discuss the development of atherosclerosis, including the predisposing factors in this case the pathophysiological changes(see Atherosclerosis )

Discuss the complications that might develop in this patient. (see Atherosclerosis - Pathophysiology, Signs and Symptoms )

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Answer 1

Atherosclerosis is derived from the Greek words athlete and skleros which means fatty mush and hard respectively. Hence, it is considered to be as the hardening which occurs in the arteries. It mainly affects the coronary arteries.

The development of atherosclerosis is triggered mainly by:

- the lipid deposition withing the intima part of the artery.

- injury of the endothelial tissue and inflammation of it.

Etiological factors:

- normally the endothelial tissue of the arteries are non reactive to various factors such as platelets and leukocytes, coagulation, fibrinolytic and also the complement factors.

- but the injury to the endothelial can occur due to tobacco use.

- hyperlipidemia- hypertension

- toxins

- diabetes

- hyperhomocysteinemia

- local inflammatory reaction which is caused by infection.

Pathophysiology:

- due to etiological factors

Leads to

- injury to the endothelial as well as inflammation to it

Leads to

- development of the atherosclerosis occurs

Leads to

- stages of development of atherosclerosis:

1. Fatty streak:

* Is the earliest lesion seem in the atherosclerosis

* It is characterized by the smooth muscle cells which are filled with lipids

* Forms a yellow coloured tinge

* Increase of the amount of areas surface involved increases along with age

2. Fibrous plaque:

* Is the beginning which shows the progressive changes in the endothelium of the walls of artery.

* Normally the repairment of the injury in the endothelium takes place but itself.

* But not in the case of coronary artery disease

* The LDLS and other triggering factors like growth factor which is release from platelets triggers the proliferation of the smooth muscle of the arteries and also the thickening of the arterial wall tales place.

* After the injury occurs, the lipoprotein transports the cholesterol as well as other lipids into the intima of the arteries.

* Then the fatty streak is covered with the formation of collagen over it forming a fibrous plaque and is in grey or white colour.

* Can be in circular manner which involves the entire lumen or in one part of the artery

* Characteristic of the plaque is smooth or irregular borders with edges which is rough and jagged

* This will lead to narrowing down of the vessel lumen and it will lead to the reduction of the blood flow to the distal part of the tissue

3. Complicated lesion:

* It is the final stage of the disease

* It is the most dangerous lesion

* With the growth of the fibrous tissue or plaque continuation in the inflammation takes place resulting in the instability, ulceration and rupture in the plaque.

* As soon as the artery wall's integrity is compromised, the platelets accumulate in large number which will lead to the formation of the thrombus

* Adherence of the thrombus to the wall of the artery takes place* this leads to further narrowing down or total occlusion of the artery

* This process will lead to the activation of the exposed platelets* this will lead to expression of the glycoprotein I1b/IIIa receptors which will bind the fibrinogen

* This will lead to further platelet aggregation and adhesion

* Leads to further enlargement of the thrombus

Complications:

- death if not treated on time

- permanent damage to the arteries

- coronary spasm

- severe ischemia

- cardiac infarction