Diseases of Blood Vessels

Diseases of Blood Vessels

Atherosclerosis

This is disease of the arteries. There is patchy changes which develop in the tunica media of arteries. There is accumulation of cholesterol compounds & calcium deposits. This makes the lumen narrower and thereby obstructing blood flow. Obesity & sedentary life style can lead to this.

Hypertension

The term hypertension is used to describe blood pressure that is sustained at a higher level than the normal level of 120/80 mmHg. The normal value differs as per age group. Prolonged hypertension affects the heart, brain & kidneys.

Cardiac failure

This is otherwise heart failure which occurs when the muscles of the ventricles are unable to maintain the circulation of sufficient blood to meet the needs of the body.

Related Notes -

 Blood vessels

There are several kinds of blood vessels. Arteries and arterioles always carry oxygenated blood from the heart, the exception being the pulmonary arteries which carry venous blood.

Venules and veins carry impure blood towards the heart except the pulmonary veins which carry pure blood.

Capiliaries are very minute blood vessels in which arterioles terminate and venules begin. They form a delicate network of vessels which ramify in most parts of the tissues of the body.

Working of the heart

The heart is a pump and the events which occur in the heart during the circulation of blood are spoken of as the cardiac cycle. In a normal heart beat the two auricles contract simultaneously while the two ventricles relax and vice versa. The term systole refers to the phase of contraction. Diastole is the phase of relaxation. A cardiac cycle consists of the systole and diastole of both auricles and the ventricles.