Circulatory system: Diseases of Blood vessels.

 

 Circulatory system: Diseases of Blood vessels.

 

Blood Vessels

The human body has a network of blood vessels all over it. The tissues are supplied oxygenated and nutrient rich blood through these vessels, and deoxygenated blood containing metabolites is drained away from these tissues through the venous channels.

 

Based on the structure, the blood vessels are of the following three types:-

 

1.Artery: It is a blood vessel that carries blood from the heart to the body. It contains oxygenated blood except for the pulmonary artery, which carries deoxygenated blood  from the right side of the heart to the lungs.

2.Vein: It is a blood vessel that carries blood from the body to the heart. It contains deoxygenated blood except for the pulmonary veins that carry oxygenated blood from the lungs to the heart.

3.Capillaries:These are  minute vessels which are found, where the arteries end the veins begin. They are in the form of a network.

 

Comparison of Artery and Vein

 

Variable	Artery	Vein
Valves	Present	Absent
Nature of blood flow	Pulsatile, forceful, high pressure.	Continuous, slow, low pressure.
Nature of blood	Oxygenated	Deoxygenated.
Colour of blood	Red	Bluish-red.
Direction of blood flow	Away from the heart.	Towards the heart.
Nature of hemorrhage in case of trauma	Pulsatile, forceful and severe.	Mild to moderate and Non pulsatile.

 

 

Diseases of Arteries

 

Definition

It is a condition characterized by progressively increasing thickening of and reduction in elasticity of vessel wall.

Aetiology

 

1.Age: Middle age and elderly.

2.Heredity and genetic predisposition.

3. Diabetes mellitus.

4.Hypertension.

5.Diet with high contents of fats in various forms.

 

Pathology

 

1.It is a degenerative disease.

2.The inner lining of thearterial wall becomes thicker, so that the lumen becomes narrower.

3.There is deposition of fat on the inner lining of the arterial wall, which further reduces the size of the lumen.

4. Due to  involvement of the small arteries, the blood supply to muscles and organs, which causes their dysfunction.

5.Loss of the fat deposits from some areas results in formation of scar. The rough surface of such scars predisposes  to the development of blood clots(thrombi).

6.Such an effect on the valves of the aorta may result in aortic stenosis or aortic incompetence. 

 

Clinical features

 

The clinical features vary, according to the blood vessels involved, as shown in the following table:-

 

Blood vessel	Features
Coronary artery	.Angina pectoris. .Myocardial infraction.
Cerebral artery	.Hemiplegia. .Monoplegia. .other cerebrovascular accidents.
Leg arteries	.Intermittent claudication. .peripheral vascular disease.                                                     .Gangrene.
Aortic valve	.Aortic stenosis or incompetence.

 

 

Treatment

 

1.Reduction in the dietetic content of the following:-

                  .Oil.

                  .Ghee.

                  .Animal fat.

2.Giving up the following:-

                  .Smoking.

                  .Drinking.

3.Adequate exercise.

4.Control  of diabetes.

5.Surgical treatment of the arterial occlusion ,if involves a critical organ.