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5.9.1. Diseases of the blood vessels

Diseases of the blood vessels

Some of the diseases of the blood vessels are:


The blood pressure is a measure of the blood pressure inside the arteries. When we measure the tension, two values ​​are given, since it is different in systole (the maximum) than in diastole (the minimum).

The blood pressure normal blood of a young adult is about 120 mmHg maximum, and 70 mmHg minimum.

If, due to different causes, such as tobacco or excessive salt consumption, hypertension occurs, there may be a risk of breaking blood vessels (effusion) or kidney failure, for example.

Mujer midiéndose su tensión arterial con un tensiómetro.

Para medir la tensión se emplea el tensiómetro. En este caso, la persona que aparece en la imagen no tiene hipertensión.


The arteriosclerosis is hardening of the arteries causing them to lose elasticity, which increases blood pressure and causes hypertension.


The atherosclerosis occurs the deposited, inside the arteries, plaques formed by the accumulation of fats and cholesterolThese plaques (atheromas) make the lumen of the artery increasingly narrow and the walls more rough, which makes it easier for platelets to adhere and form clots that prevent the passage of blood due to an artery obstruction.

La aterosclerosis se produce por el depósito de placas de ateroma

By NHLBI [Public domain], via Wikimedia Commons


An aneurysm is a dilation or bulging of a blood vessel. It occurs when, for example, due to atherosclerosis, the blood pressure that circulates through an artery causes a dilation that, if it stretches the artery so much that it breaks, can cause a  fatal hemorrhage.

Varicose veins

The veins are dilations of the veins due to the inability of the blood to return to the heart by an alteration of the venous valves.

When we move our legs or walk, the calf muscles press on the veins and push the blood, against gravity, towards the heart. The semilunar valves prevent the backward movement of the blood, but if they do not close properly, the blood accumulates in the veins causing them to dilate .

The most common varicose veins are those of the legs, but they also appear in other sites such as the esophagus (esophageal varices), anal region (hemorrhoids or piles, bulging veins in the anal area) or in the testicles (varicocele).


By National Heart Lung and Blood Institute. (Varicous veins.) [Public domain], via Wikimedia Commons


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