Among the malformations of the cardiovascular system: dextrocardia occupies a special place.This anomaly or go unnoticed for many years (sometimes lifelong), or - lead to death shortly after birth.It all depends on its combination with a mirror arrangement of internal organs
normal structure of the cardiovascular system
human cardiovascular system has two main components:
- Heart.Central Authority.It provides blood flow through the vessels.
- vessels.The hollow tubular bodies in which the blood moves.
Heart.Its length varies between 10-15 cm. The base has a width of 8 to 10 cm. Then the upper part is not wider than 7.6 cm. Body weight of an adult is 250-300 grams (males is greater than for women).And it is not less than 1/3 of it falls on the left ventricle.Since it bears the greatest burden among the other parts of the heart and is the most developed muscle layer.
daily cuts heart about 86 thousand times / day at an average rate of 60-90 beats per minute.This provides a continuous blood flow thr
vessels.Accordingly, the principle of blood flow direction of all the vessels are divided into arterial (carry blood from the heart) and venous carry blood to the heart).The number and size of vessels vary greatly from a few centimeters (from aorta) to micrometers (in capillary).
Since the cardiovascular system is a closed, a schematic arrangement of blood vessels can be represented as the following chain:
- vena cava.Most large vessels, venous type.They bring blood to the heart.
For the most part the structure of the veins and arteries as different.The first vessels are so-called capacitive type.They have a greater ability to stretch due to a weak (as compared to arteries) of the muscle layer.As veins are provided with valves to provide a one-sided flow of blood.The exception is the pulmonary circulation.But more about this later.
circulation provides blood distribution in the body.It should be recalled that the oxygen content of whole blood is divided into two groups.
- Arterial.Rich oxygen atoms.Usually it moves from the heart (the exception - the vessels of the pulmonary circulation).
human circulatory system is closed.And for the uninterrupted supply of the body with oxygen and nutrients, there are two circulation.
- Small circulation.Its main purpose is blood oxygen saturation.It starts from the right ventricle, from the blood through the pulmonary artery (although it carries venous blood) goes into the lungs.Where the artery splits up to the capillaries and densely twist around the broncho-pulmonary system.Due to which gas exchange occurs.The blood then goes on pulmonary vein into the left atrium.
- Large circulation provides blood flow throughout the body.Starting from the left ventricle from the arterial blood out into the aorta.From her blood moves into smaller vessels and ensures the supply of the whole organism.Then it through the system of the vena cava flows into the right atrium.
This is important!Heart disease consisting in fully mirror the location of the heart is called dextrocardia.It is as follows: the right heart as if roles are reversed with the Left.There are three possible options for further human development.
isolated dextrocardia leads to the fact that the right half of the left act as the circulation departments.The right ventricle is the largest due to the significant development of the muscular wall.In this case it goes from the pulmonary artery.
The left ventricle is the opposite - fall vena cava.Accordingly, from the left ventricle, which has a structure of the right ventricle comes from a healthy heart the aorta.
vnutriututrobnogo During development, this situation has practically no effect on the child, because it depends largely on the circulation of the mother.But in the recent months may begin dilation of the left departments.At birth, it achieves a considerable size, which leads to early death.The fact that the left ventricle and atrium are arranged as well as a normal right heart sections.But carry the load of the left departments.This leads to their rapid "amortization".
dextrocardia heart vessels without bias.Deadly option.During fetal development can only be observed fetal malnutrition, because gas exchange occurs in the placenta.But immediately after the birth of a child dies, as not capable of independent life.According to the pulmonary artery is the arterial blood, and into the systemic circulation - venous.But as the veins have valves, and liver, and all other non-paired organs located on the usual for a normal person experiences a strong local blood flow obstruction.
dextrocardia with a mirror arrangement of internal organs and blood vessels.Due to internal organs which are arranged specularly relative to a conventional man.This option is absolutely nothing like not manifest itself throughout life.