Guadalajara BJF

Language: Spanish
References: 27
Page: 30-40
PDF size: 559.56 Kb.

ABSTRACT

The heart is an hydraulic pump whose function is to provide oxygenated blood to all tissues, and to send unsaturated blood back to the lungs to maintain life; is an organ which pumps tireless since before birth; it is estimated that a 75 year old man heart has had more than 550 million beats in his lifetime.
Traditionally the heart was considered as formed by differentiated cells, which means that en old age, the heart has the same myocells it had at birth, but recent investigations confirm that heart is a dynamic organ, and between the years 20 an 100, its cell compartment has been replaced from 10 to 15 times.
Today the heart physiology and pathophysiology of the myocardial cells is better understood, as well as the role of the final portions of chromosomes, named telomers, which shorten its terminal ends as they replicate; nevertheless, they are able to restore its function through the enzyme transcriptase reverse telomerase; when the telomers reduce its length to a critical point, this loss of function induce endothelial dysfunction; the shortening of the telomers length is directly related to the heart senescence.
Several chronic diseases affect the heart: high blood pressure, diabetes mellitus, atherosclerosis, etc., therefore it is important to detect them early and to treat them accordingly, for a secondary prevention may avoid further disorders.

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