Varicose veins are a disease that is based on the irreversible expansion of the diameter of the veins and loss of function of the venous valves.
Where is the second heart
To understand the causes of varicose veins, it is necessary to turn to the peculiarities of the structure and functioning of the venous system.
Veins refer to blood vessels that carry blood from tissues and organs. Unlike the arteries that move blood from the heart and distribute it from top to bottom, most veins in the body run from bottom to top. The main driving force in the arteries is the energy of heart contractions. On the way to the organs, it is consumed almost completely and cannot provide a stable return of blood to the heart.
The structural features of the venous system help maintain full blood circulation. They can be divided into:
- central;
- peripheral.
Central are the residual blood pressure that is transmitted to the veins after the blood passes through the arterial system and the suction action of the diaphragm. This is the muscular barrier that separates the thoracic cavity from the abdomen. The large venous vessels pass through the diaphragm. When you inhale, it descends, squeezing the venous vessels, and when you exhale, it rises. These movements work like a pump, helping the blood to flow up the veins to the heart.
Peripheral factors include:
- muscle-venous pump;
- venous valves;
- venous tone.
The role of these factors in blood flow is so great that they are called the second heart of the body.. . . Dysfunction of any of them can be a starting point in the development of varicose veins.
Muscle-venous pump
The main force that makes the blood move from the organs to the heart is the contraction of the muscles around the veins. This is the so-called musculoskeletal pump. During walking, exercise muscle fibers contract, this leads to narrowing of the lumen of the venous vessels, as a result of which blood is pushed into the upper extremities.
Venous valves
There are valves in the veins to prevent the return of blood when the muscle fibers relax. They are growths on the inner surface of the vessel wall, which are a thin elastic plate. The flap valves are aimed at the heart.
The principle of their work is as follows: when the muscle fibers relax and the blood tends to return downward by gravity, it enters the space formed by the flap sheet and the vessel wall. The pressure created by the blood in this area causes the valves to close, which prevents it from returning.
Venous tone
Venous tone ensures the maintenance and regulation of vascular capacity. It is provided by the connective tissue and muscle fibers that make up the venous wall. Special nerve cells, which are located in the thickness of blood vessels, respond to blood pressure by signaling muscle cells and connective tissue fibers. The lumen of the vein is reduced, as a result of which the blood moves to the heart.
Thus, the stable functioning of the venous system depends on the proper functioning of all its components. Understanding these mechanisms means making the treatment of varicose veins most effective.
Between cause and effect
To date, there is no single theory for the development of varicose veins. The biggest difficulty is to separate the direct cause of the disease and the conditions that only contribute to its manifestation.
Varicose veins are a genetic disease that occurs only when exposed to certain adverse factors.
In people prone to varicose veins, there is a congenital disorder of the structure of the vessel wall and a decrease in the number of valves. As a result, the two most important mechanisms of blood flow from the organs to the heart suffer: venous tone decreases and the valvular apparatus does not work.
The simplified development of the disease in this case is as follows. The blood that is pushed through the vessels due to muscle contraction tends to down during the relaxation phase of the muscle fibers under the influence of gravity. If there are few venous valves or their valves are not able to effectively block the lumen of the vessel, the blood returns to the lower extremities. In case of insufficient elasticity and elasticity of the venous wall, a marked expansion of the vessel diameter is observed. As a result, the valve teeth move further away from each other, allowing even more blood to flow down. A pathological vicious circle is developing. These are varicose veins.
However, in a healthy body, even in the presence of congenital changes in the venous vessels, the development of the disease does not occur. For this mechanism to work, the impact of one or more adverse factors is required. They include:
- Lifestyle;
- hypodynamia;
- obesity;
- hormonal imbalance;
- pregnancy.
Lifestyle
Lifestyle characteristics lead to increased pressure in the veins, which leads to increased stress on the vascular wall.
This is most often observed during prolonged standing or sitting and during work involving constant weight lifting. The development of varicose veins is provoked by tight underwear, jeans, which compress large veins at the level of the inguinal folds. Nutrition is also important: the consumption of refined foods, the lack of fresh fruits and vegetables in the daily menu - sources of fiber. Such a diet leads to the development of constipation, which increases intra-abdominal pressure.
Hypodynamia
As you know, muscles are the second heart for veins, because of their contraction the walls of the vessels compress and the blood moves. With a sedentary lifestyle, this mechanism of blood circulation is lost. The degree of muscle development also plays an important role - the better the muscle is developed, the easier it is to do the work of promoting blood. This is the reason for the rare occurrence of varicose veins in athletes.
obesity
Obesity is a reliable risk factor for the development of varicose veins in women. At the same time, such dependence was not detected in men.
Hormonal imbalance
Female sex hormones - estrogen, progesterone - in quantities exceeding physiological norms, affect the vein wall and reduce its tone. This is due to the gradual destruction of the connective fibers, which provide its strength and elasticity. Hormonal contraceptives, hormonal drugs for the treatment of menopause play an important role in the development of varicose veins.
Pregnancy
The increase in the volume of circulating blood, the compression by the uterus of the large veins that pass behind its posterior wall, the increase in intra-abdominal pressure make pregnancy one of the main causes of varicose veins in women.