Varicose veins are a disease based on the irreversible enlargement of the diameter of the veins and the 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 the blood vessels that carry blood from tissues and organs. Unlike arteries, which move blood from the heart and distribute it up and down, most veins in the body flow from the bottom up. The main driving force of the arteries is the energy of the heart's contractions. On the way to the organs, it is almost completely consumed and cannot provide a stable return of blood to the heart.
The structural features of the venous system help maintain full circulation. They can be divided into:
- central;
- peripheral.
The central ones are the residual arterial pressure, which is transmitted to the veins after the blood passes through the arterial system, and the suction action of the diaphragm. It is a muscular septum that separates the thoracic cavity from the abdomen. The great venous vessels traverse the diaphragm. When you inhale, it descends compressing the venous vessels, and when you exhale, it rises. These movements work like a pump, helping blood flow through the veins to the heart.
Peripheral factors include:
- muscle-venous pump;
- venous valves;
- venous tone.
The role of these factors in the bloodstream is so important that they are called the second heart of the body.. . . The dysfunction of any of them can be the starting point in the development of varicose veins.
Muscle-venous pump
The main force that moves blood from the organs to the heart is the contraction of the muscles that surround the veins. This is the so-called muscle-venous pump. When walking, exercising, muscle fibers contract, this leads to a narrowing of the lumen of the venous vessels, as a result of which the blood is pushed into the overlying sections.
Venous valves
To prevent blood from flowing back at the time the muscle fibers relax, there are valves in the veins. They are outgrowths on the inner surface of the vascular wall, which are a thin elastic plate. The flaps of the valves are directed toward the heart.
The principle of their work is as follows: when the muscle fibers relax and the blood tends to go back down by the force of gravity, it enters the space formed by the valve leaf and the wall of the vessel. The pressure created by the blood in this area causes the valves to close, preventing it from flowing backward.
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, found in the thickness of blood vessels, react to blood pressure by sending signals to muscle cells and connective tissue fibers. The lumen of the vein is reduced, as a result of which the blood moves towards the heart.
Therefore, the stable functioning of the venous system depends on the correct functioning of all its constituent parts. Understanding these mechanisms means making varicose vein treatment the most effective.
Between cause and effect
To date, there is no single theory about the development of varicose veins. The greatest difficulty is the separation of the direct cause of the disease and the conditions that only contribute to its manifestation.
Varicose vein disease is a genetically determined disease that manifests itself only when exposed to certain unfavorable factors.
In people susceptible to varicose veins, a congenital disorder of the structure of the vascular wall and a decrease in the number of valves were found. As a result, the two most important mechanisms of blood flow from the organs to the heart suffer: the venous tone decreases and the valve apparatus does not work.
The simplified development of the disease in this case is as follows. The blood, which is pushed through the vessels due to muscle contraction, tends downward during the relaxation phase of the muscle fibers under the influence of gravity. In the event that there are few venous valves or their valves cannot effectively block the lumen of the vessel, the blood flows back to the lower sections. With insufficient elasticity and elasticity of the venous wall, a pronounced expansion of the diameter of the vessel occurs. As a result, the valve cusps are further separated from each other, allowing an even greater volume of blood to flow downward. A pathological vicious cycle develops. 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 necessary. These include:
- Lifestyle;
- hypodynamics;
- obesity;
- hormonal imbalance;
- the pregnancy.
Lifestyle
Lifestyle characteristics lead to increased pressure in the veins, resulting in increased tension on the vascular wall.
This is most often seen when standing or sitting for a long time and during work associated with constant weight lifting. The development of varicose veins is provoked by tight underwear, jeans, which squeeze the large veins at the level of the inguinal folds. Nutrition is also important: the consumption of refined foods, the absence of fresh fruits and vegetables in the daily menu, sources of fiber. Such nutrition leads to the development of constipation, which increases intra-abdominal pressure.
Hypodynamics
As you know, the muscles are the second heart of the veins, due to their contraction, the walls of the vessels are compressed and the blood moves. With a sedentary lifestyle, this circulatory mechanism is lost. The degree of muscle development also plays an important role: the better the muscle develops, the easier it is to cope with the work of promoting blood. This is the reason for the rare appearance of varicose veins in athlete-athletes.
Obesity
Obesity is a reliable risk factor for the development of varicose veins in women. At the same time, such dependence was not revealed in men.
Hormonal imbalance
Female sex hormones (estrogens, progesterone) in amounts that exceed physiological norms affect the wall of the vein and reduce its tone. This is due to the gradual destruction of the connective fibers that give it strength and elasticity. Hormonal contraceptives, hormonal drugs for the treatment of menopause, play an important role in the development of varicose veins.
The pregnancy
An increase in the volume of circulating blood, compression by the uterus of the large veins that pass behind its posterior wall, an increase in intra-abdominal pressure make pregnancy one of the main causes of varicose veins in women.