It is difficult to overestimate the role of the circulatory system, which is the connecting link that allows all parts of the body to function normally. The liquid state of the blood and its normal flow ensure proper metabolism in the tissues , and, therefore, support its vital activity and the performance of vital functions. Any change, in particular the formation of a blood clot, seriously affects the functioning of the organ and can cause irreversible and very dangerous consequences.
The fluid state of the blood is maintained thanks to the coordinated work of the coagulation and anticoagulation systems. Under unfavorable circumstances, discoordination of their activities with the occurrence of bleeding or thrombosis is possible.
Thrombosis is the process of intravital formation of blood clots in the lumens of blood vessels or chambers of the heart. Each of us has encountered this phenomenon, since the formation of blood clots is aimed primarily at stopping bleeding. With the most minor injuries, scratches, cuts in the area of tissue damage and vessel walls, blood clotting is inevitably activated to prevent bleeding. This is a kind of protective mechanism invented by nature to preserve life, but often this process takes on the features of pathology.
To maintain the fluid state of the blood, there is an anticoagulation system. Through various enzymes, it breaks down fragments of already formed thrombotic masses, fibrin complexes and cellular aggregates that can cause blockage of blood vessels, but it may not be able to cope with large or multiple rapidly appearing clots formed in various pathologies.
With various diseases of the circulatory system, pathology of the vascular wall, hemostasis, metabolic disorders, prerequisites for thrombus formation arise, then clots can be found in veins, arteries of different diameters and even in the cavities of the heart.
Thrombi, being in the lumen of the vessel, impede the movement of blood, and this contributes to hypoxic and ischemic disorders in the tissues. If the bundle covers more than 90% of the vascular lumen, then infarctions with necrosis of organ or tissue cells are possible. It is easy to guess that a heart attack in the heart, brain tissue, intestines and other organs can not only cause a disruption in the functions they perform, but also cause death.
To understand the essence of thrombosis, it is necessary to find out what are the main causes of blood clots, why exactly this phenomenon is dangerous and what consequences can occur after thrombosis.
Among the causes of thrombosis are:
atherosclerosis is a process that promotes thrombus formation in the arteries
A healthy, smooth vascular wall is the key to good blood flow, however, with various damage to it, the coagulation system is activated and thrombosis occurs. On the one hand, this is a protective mechanism in case of injury, on the other hand, it is a pathological condition with various kinds of changes in the internal lining of the vessel. Thus, inflammatory processes (vasculitis) and the very common atherosclerosis are often the causes of pathological thrombus formation outside of traumatic injuries. Surgical interventions, infectious diseases, and malignant neoplasms are also accompanied by thrombosis.
A change in the coordinated functioning of the coagulation and anticoagulation systems provokes the activation of a number of enzymes and protein fractions, causes aggregation of formed elements, and the consequence is thrombosis in a variety of tissues and organs. Such conditions are often accompanied by autoimmune disorders, severe infections, tumors of the hematopoietic system, shock and even genetic defects.
A change in the nature of blood flow through a vessel affects the state of the inner lining (endothelium), which can be damaged, causing thrombosis. These phenomena can be observed especially clearly in the areas of branching of large vessels, where laminar blood flow is replaced by turbulent one, and blood under high pressure and at high speed seems to hit the vascular wall at the mouths of other vessels, damaging the endothelium (inner layer). If there are any changes in such areas (atherosclerosis, for example), then thrombus formation will occur more intensely.
To a large extent, the appearance of blood clots in the vessels is facilitated by a slowdown in blood flow and its stagnation, which can be observed with varicose veins of the legs (venous insufficiency), chronic heart failure, prolonged immobilization of the patient after surgical operations, and in bedridden patients.
Heart rhythm disturbances (atrial fibrillation, various types of blockades, etc.) lead to thrombosis not only of peripheral vessels, but also of the chambers of the heart. In addition, intracardiac thrombi often accompany valve lesions in rheumatic or atherosclerotic diseases; they form after implantation of artificial valves or other cardiac interventions. Often in such cases, a blood clot breaks away from the site of its formation and circulates with the blood, reaching other organs and causing dangerous consequences in them.
An increased tendency to thrombosis is found in pregnant women, as well as when taking contraceptives. This possibility must be taken into account, and a coagulogram will help to identify a blood clotting disorder in time.
Smoking, a sedentary lifestyle, the presence of cardiovascular pathology, autoimmune diseases, as well as hereditary predisposition are risk factors for possible thrombosis.
Venous thromboses occupy a special place during air travel, and according to some data, at least one passenger on each flight develops them during the journey. This is facilitated by pressure fluctuations, stagnation of blood in the vessels of the legs, and prolonged exposure to an uncomfortable position, so if you have varicose veins or heart problems, you need to be extremely careful when planning long trips by plane.
The process of blood clot formation is very complex, consisting of many sequential reactions involving blood cells, a large number of enzymes, proteins, biologically active substances and trace elements. Only a specialist hemostasiologist or laboratory diagnostics doctor can reproduce the entire cascade of these reactions, but for most general doctors this will be quite problematic.
Depending on which vessel the thrombus occurred in, it is customary to distinguish between venous and arterial thrombosis. The nature of the clots, the speed of their formation and even their appearance will differ.
thrombosis and embolism (thromb rupture) using the example of leg veins
In general terms, the process of thrombus formation in pathology consists of a number of sequential stages, with each previous one triggering the next one:
The resulting blood clot is firmly fixed to the site of endothelial damage, however, in some cases, the entire blood clot or its fragments can break off and enter other tissues and organs, leading to circulatory disorders. The phenomenon in which a blood clot or its fragment comes off is called thromboembolism , and a clot moving with the blood is called thromboembolus . When it blocks another vessel, they speak of embolothrombosis. This condition is extremely dangerous due to the development of a heart attack - tissue necrosis in the area of blood supply to the blocked vessel.
The reasons for the detachment of a blood clot can be very diverse: the rapid speed of blood flow through the vessel, the large size of the clot, progressive vascular disorders at the site of attachment of the blood clot, the inflammatory process, excessive physical activity, and when the clots are localized on the heart valves - their constant movement and high pressure during every contraction of the myocardium.
Thrombotic masses differ in their appearance, composition, and their sizes can vary from microscopic to quite massive (in the aorta, vena cava, heart cavities).
Depending on the composition and appearance, the so-called white , red blood clots, mixed structures and hyaline convolutions are distinguished.
the structure of the most typical arterial thrombus - mixed thrombus. Consists of a white thrombus (head), a mixed zone (body) and a red thrombus (tail)
White blood clots are made of platelets, fibrin protein and leukocytes, and are found in arteries where blood flow is quite intense. Red blood clots contain a significant amount of red blood cells, giving them a red color, and they can be found in the venous bed. Mixed convolutions consist of areas of both white and red thrombus, and hyaline ones are characteristic of small vessels of microcirculation.
If the thrombus completely closes the lumen of the vessel, it is called occlusive , and if it is located near the wall and does not interfere with blood flow, it is called parietal .
Signs of thrombosis are determined by its location and the degree of obstruction of the blood vessel. The main symptom is always pain in an organ with impaired blood flow.
Most often, blood clots appear in the arterial vessels of the brain. The causes may be atherosclerotic plaques, vasospasm against the background of a hypertensive crisis, the presence of an aneurysm or vascular malformation.
Clinical signs of thrombosis of a large cerebral artery are reduced to the symptoms of a stroke: intense headache, loss of sensitivity and motor function in certain parts of the body, impaired speech, vision, memory, etc. If the thrombosis is partial with incomplete closure of the lumen of the vessel, then the changes will be of a chronic ischemia with signs of discirculatory encephalopathy, dementia.
thrombosis of a large cerebral artery - actually a stroke or micro-stroke with corresponding symptoms and consequences
Embolism of blood vessels in the brain is also possible when detached blood clots from another location penetrate into them with the bloodstream. Signs of such embolism are also most often caused by necrosis of nervous tissue (stroke), and among the causes may be damage to the valve leaflets of the heart, which occurs with rheumatism, atherosclerosis, syphilis, and septic endocarditis.
In addition to the arterial one, a venous thrombus may also occur in the head. Most often, the sinuses of the dura mater and the veins that carry blood from the brain are affected. The causes of thrombosis are septic conditions with the presence of purulent foci in the skull or outside it. Venous thrombosis is also possible in pregnant women and after childbirth. Symptoms of venous sinus thrombosis include severe headache, nausea, vomiting, dysfunction of the cranial nerves, paresis, paresthesia, paralysis, and fever. The described changes threaten the lives of patients and require emergency neurosurgical care and intensive treatment in the intensive care unit.
The classic manifestation of coronary thrombosis against the background of atherosclerotic lesions is coronary heart disease. If the clot does not completely block the lumen of the artery, then chronic ischemic heart disease develops in the form of angina pectoris with heart pain and shortness of breath. If the lumen of the vessel is completely closed, a heart attack will develop: blood will not move through the affected artery and the area of the heart muscle will undergo necrosis (death).
The symptoms of myocardial infarction are familiar to many: intense pain in the heart area, shortness of breath, a feeling of fear of death, cyanosis, cardiac arrhythmias, and others.
A blood clot in the heart can be located both on the inner walls of its chambers and on the valve flaps. During various inflammatory processes (endocarditis), atherosclerotic lesions, damage occurs to the inner lining of the heart - the endocardium, which inevitably leads to activation of the blood coagulation system and thrombus formation. The presence of a foreign body in the form of an artificial valve also triggers such mechanisms.
Intracardiac thrombosis is dangerous not only by the development of acute or chronic heart failure, but also by the so-called thromboembolic syndrome, when detached clots rush into the systemic circulation, settling in the vessels of the brain, kidneys, spleen, intestines and causing necrotic changes in them.
blocking of the vein lumen by a thrombus
Vascular thrombosis of the lower extremities is often associated with vein pathology, when varicose veins, blood stagnation, and changes in hemostasis contribute to thrombus formation. An arterial thrombus in the leg or arm can form due to injuries, atherosclerotic lesions, or inflammation in the arteries.
Symptoms of thrombosis of the blood vessels of the legs are reduced to intense pain, swelling, blueness of the skin, changes in skin temperature with massive damage. Closure of one of the veins is accompanied by swelling and minor pain in the calf muscles, while the general condition of the patients is satisfactory. When the bundle is localized in the superficial veins, it is possible to palpate the dense contents in a certain area of the vessel.
Elderly people, patients suffering from diabetes mellitus, and those who are overweight are highly susceptible to thrombosis of the deep veins of the lower extremities. The risk group includes people who have undergone long-term surgical interventions, as well as pregnant women.
The danger of venous thrombosis of the legs lies not only in local circulatory disorders, but also in the possibility of a blood clot breaking off and impairing blood flow in the lungs. Migrating from the veins of the lower extremities to the inferior cava, then through the right half of the heart, blood clots rush into the pulmonary trunk and its branches, blocking blood flow in the pulmonary circulation. This condition is called pulmonary embolism.
As mentioned above, the most common cause of pulmonary vascular thrombosis is embolism from the deep veins of the lower extremities. Blocking the blood flow at the level of the pulmonary trunk inevitably leads to the death of the patient if the thrombus is not urgently removed. Most often, patients do not have time to receive timely help, since thromboembolism occurs suddenly outside a medical institution. Thrombosis of the lobar branches of the pulmonary artery leads to exclusion of the entire lobe from the breathing process. The mechanism of the pathological effect of massive thrombosis comes down to a reflex spasm of the coronary arteries, which leads to acute heart failure.
mechanism of pulmonary embolism and risk areas for thrombus formation with subsequent embolism
Symptoms of thromboembolism of the branches of the pulmonary artery consist of sudden acute pain in the chest, severe shortness of breath up to respiratory arrest, cyanosis, and cardiac dysfunction. Thrombosis of small vessels of the lungs can be chronic and recurrent, especially in patients suffering from atrial fibrillation, and their symptoms include shortness of breath, dry cough and chest pain.
Arterial thrombosis of mesenteric vessels is not uncommon in patients with atherosclerosis. In this case, against the background of characteristic changes in the vascular wall in the form of fibrous plaques with rupture, atheromatosis, local hypercoagulation occurs, and the lumen of the vessel or the mouth is blocked by a thrombus. The first symptoms will be abdominal pain, vomiting, diarrhea, then, as necrosis of the intestinal wall develops, symptoms of intoxication will increase, and peritonitis is possible. Without timely surgery, such changes inevitably lead to death.
Separately, it is necessary to say about such a dangerous condition as thromboembolic syndrome. The source of thrombosis in this case can be the veins of the legs, pelvis, affected heart valves or parietal endocardium.
Symptoms of a blood clot rupture will be reduced to signs of damage to the organ in whose vessels the thromboembolism has stopped. This may be acute pulmonary heart failure with shortness of breath, cough, arrhythmias up to respiratory and circulatory arrest, signs of stroke, myocardial infarction, renal failure or intestinal necrosis.
In order to determine the presence of a blood clot, the doctor will find out in detail the nature of the complaints, the time of their appearance, the connection with various external factors, as well as the presence of pathologies of the cardiovascular and other systems. After a detailed questioning, the patient will be examined and palpated, if this is possible and appropriate for the given location of thrombosis.
As a rule, the clinical picture is quite enough to suspect thrombosis of a particular location.
To confirm the diagnosis, a coagulogram is usually prescribed to determine APTT, INR, prothrombin index, D-dimers, etc.
You can also check blood vessels for blood clots using instrumental methods, for example, ultrasound. Ultrasound with Dopplerography allows you to determine the location and size of blood clots in the veins of the extremities, and the state of blood flow in the vessels.
Phlebography consists of the introduction of a radiopaque substance followed by X-ray examination. This method is applicable for thrombosis of blood vessels in the legs.
blood clots in the vessels of the legs on an MRI image
If damage to various organs is suspected, CT, MRI, X-ray of the lungs, ultrasound of the abdominal organs, heart, etc. are performed.
Thrombosis can be treated both in a hospital and at home. Tactics are determined by the location and extent of vascular damage.
Methods to combat blood clots include:
Patients with thrombosis of any location are prescribed bed rest, and most often treatment is carried out in a hospital.
Drug therapy involves the prescription of anticoagulants. One of the most famous and long-used direct anticoagulants is heparin, however, its use is associated with a large number of side effects (allergic reactions, bleeding) and requires careful constant monitoring of hemostasis, so currently preference is given to low molecular weight heparins - fraxiparin, clexane, fragmin. These drugs give significantly fewer adverse reactions, are very convenient to use and can be administered independently by the patient.
Indirect anticoagulants, for example, an anti-blood clot medicine such as warfarin, prevent thrombosis and are usually prescribed for an increased risk of thrombosis in patients with an implanted artificial valve, chronic heart failure with damage to the valve leaflets, as well as after acute thrombosis, starting from the third day. The use of such drugs must be accompanied by mandatory monitoring of a coagulation indicator such as INR, which should not exceed three units.
For preventive purposes, patients with cardiovascular diseases, with an increased risk of thrombosis due to other reasons, are often prescribed aspirin in a small dose.
Thrombolytic drugs (streptokinase, urokinase) are designed to dissolve formed blood clots in the vessels. Their prescription and administration is carried out intravenously and only in a hospital setting under the supervision of a physician. Small clots dissolve during thrombolysis, so their administration is effective in the early stages of the disease, since their later use is fraught with fragmentation of large clots with the risk of pulmonary embolism.
vena cava filter prevents thrombus embolism into vital vessels
Surgical treatment consists of an operation to remove the blood clot (thrombectomy) or install a vena cava filter. During thrombectomy, the clot is removed by inserting a catheter into the vessel. A vena cava filter is a special device that is installed in the inferior vena cava and prevents the penetration and further spread of blood clots into the vessels of the lungs, heart, etc. This operation is especially effective for a floating thrombus, which is fixed at one end to the vessel wall and free at the other located in the lumen, creating a threat of embolism.
Among non-drug methods of combating thrombosis, elastic bandaging is widespread. Currently, it can be replaced by wearing compression hosiery, which is sold in specialized stores and pharmacies, or is made individually. The degree of compression is determined by a phlebologist, and such underwear should be worn in the morning before getting out of bed.
It should be noted that it is possible to clear blood vessels from blood clots only with proper treatment using anticoagulants, thrombolytics, and also through surgery. Self-medication in the case of thrombosis of any location can be very dangerous.
In case of thrombus formation in the vessels of the heart, lungs, and brain, in addition to thrombolytic therapy, other measures are taken to maintain and correct the function of these organs.
The consequences of thrombosis are often unfavorable and are caused by impaired blood flow in organs and tissues. With arterial thrombosis, the development of gangrene or heart attack (heart, brain, intestines, limbs) is possible; with venous thrombosis, especially in the vessels of the legs and pelvis, there is a high probability of pulmonary embolism. On the part of the blood clot itself, it may become inflamed with involvement of the vein wall (thrombophlebitis), fragmentation, or secondary infection.
To avoid thrombosis and its complications, you need to follow simple rules for preventing this dangerous condition:
Thrombosis is a rather dangerous phenomenon, but following simple rules of work and rest, a healthy lifestyle, and timely preventive measures will help to avoid it.
What is thrombophlebitis? Inflammatory reactions in the venous walls, accompanied by the formation of blood clots in their lumens, are called thrombophlebitis (thrombosis) in medicine. In 90% of cases, the disease affects the vessels of the legs - the superficial and deep venous networks and the perforating veins connecting them.
As a closely related disease, we can note phlebothrombosis, characterized by the same signs (thrombi in the venous cavities), but without the influence of inflammatory reactions. This disease does not have a long course, because any vascular pathology always ends with inflammation and the development of thrombophlebitis.
Most often, the pathology manifests itself as thrombosis of the superficial saphenous veins, which develops accompanied by varicose veins or CVI syndrome (impaired venous outflow). In this case, the disease often recurs, progresses, and is fraught with various complications.
Until the middle of the last century, the formation of blood clots inside blood vessels was an absolute mystery. Why does the same blood, in some cases, flow through the vessels unhindered, while in others it clogs their lumen with clots?
The famous German doctor, Rudolf Vikhrov, working at the Berlin Charité clinic, studied various mechanisms affecting changes in the structure of plasma cells and identifying the prerequisites for the development of thrombosis.
He identified the main components of the development of the disease, which remain in the practice of modern medicine under the definition of Vikhrov’s trinity (Trias). Its component is due to:
1. Changes in the vascular structure, directly in the internal lining of blood vessels
An important factor is any destructive changes in the inner choroid, including traumatic effects. It has been observed that the accumulation of blood clots always occurs in areas of obvious structural changes in the vascular walls. The initially smooth, healthy surface of the endothelium becomes rough in painful and damaged areas.
Small blood clots, floating by, attach to the rough surface and settle on the wall of the vessel. Clots accumulate and intertwine with each other, forming a thrombus that completely blocks the vascular lumen. Pathological changes in the endothelium can cause various reasons:
Microorganisms of various infections contribute to destructive changes in the epithelial intravascular layer. Due to the entry of a huge toxic mass into the blood plasma, the possibility of blood clots sharply increases, which may well cause thrombophlebitis
development of thrombophlebitis, photo
Dr. Vikhrov established: the most common places in the vascular beds where clots form are zones of uneven flow of blood plasma and a change in its speed. For example, the flow in the central part of the lumen is fast, and along the edges of the vessel the flow slows down, forming turbulence.
This feature of blood flow is typical in areas of narrowed or expanded areas of the vascular bed. Which could be a consequence of an aneurysm or varicose veins. The most prone to the formation of thrombosis are places of vascular branches, where turbulence in the blood flow is a frequent occurrence.
Impaired blood flow speed is caused by:
3. Hyperviscose syndrome (thick blood)
Vikhrov named “thick blood” as another cause of thrombophlebitis of the lower extremities. Today there is no such term in medicine; it refers to the level of its viscosity. There are no standard standards; each of us has a different viscosity level. But, there are circumstances when one patient has different viscosity of blood plasma in different vascular areas.
The main cause of thrombophlebitis is abnormal loss of fluid due to insufficient intake or excessive excretion: heavy sweating, heavy exercise causing thirst, or illness accompanied by fever. In addition, the development of thrombophlebitis is influenced by the indicators of plasma factors of the anticoagulation and coagulation system.
Under completely identical circumstances, the level of hypercoagulation (clotting) can show different indicators - very high, increased or decreased, each specific case is due to the special properties of hematopoiesis (hematopoiesis), metabolic processes, the lack of a specific protein that delays the process of plasma coagulation (sometimes this is an innate defect).
A common cause of thrombophlebitis is blood with impaired hemostasis (dissolution of blood clots). Hemostasis dysfunction is caused by:
By their nature, thrombophlebitis can be infectious or non-infectious (aseptic). Which in turn manifest themselves in various types.
The infectious form of the disease manifests itself:
Non-infectious (aseptic) form:
According to the nature of the clinical picture - acute thrombophlebitis and a form of chronic course.
According to the zone of manifestation (localization) - damage to the superficial and deep network of veins on the extremities, a form of iliofemoral lesion
manifestations of thrombophlebitis, photo
The onset of the disease may appear unexpectedly - with excellent health, the first signs of thrombophlebitis quickly form.
If treatment is not started in time at this stage, inflammatory reactions quickly spread throughout the vascular bed, significantly worsening the patient’s condition.
It should be noted that there are thromboses classified as “silent” forms that do not manifest any symptoms at all. The patient’s condition worsens after the fact – when a blood clot completely blocks the vascular lumen.
The picture of the clinical manifestation of the disease mainly depends on the location of the blood clot, the extent of the inflammatory reaction, and the level of damage to surrounding tissues.
Symptoms of saphenous vein damage
Already existing large nodular varicose formations aggravate the situation, manifesting themselves in structural changes in the vascular walls. The nodes are susceptible to soldering to the skin, injury and scratching, which causes trophic changes in the skin, facilitating easy penetration of infection. As a result, inflammatory processes form and thrombophlebitis of the superficial veins develops. Symptoms are characterized by:
The venous network of the thigh and lower leg is most affected. There is widespread swelling of the ankle and enlargement of the inguinal lymph nodes. Usually the general condition is not disturbed, pain during movement is moderate, and does not interfere with the patient’s ability to work.
In advanced cases, the spread of inflammatory reactions exacerbates the symptoms of thrombophlebitis. There is a sharp increase in pain and an increase in temperature to high levels. The persistence of acute symptoms can last up to one and a half months.
Subcutaneous migrating thrombosis deserves special attention. The nature of the disease is due to the formation of a large number of thrombotic clots in the subcutaneous vessels. Symptoms are characterized by moderate manifestations without affecting general well-being.
The positive aspect is due to the absence of any trophic changes or traces. After a certain time, the inflammatory reaction migrates to another area of the extremities, which fully justifies the name of the disease.
Signs of damage to the deep network of veins
The development of such a pathology is typical for victims of bone fractures in the area of the thighs or lower legs, the treatment of which was carried out using surgical techniques. Or during abdominal operations and surgical treatment of chest pathologies. The formation of thrombosis is facilitated by an increase in the coagulation factor, which is necessary to prevent bleeding during surgery.
Symptoms of thrombophlebitis when localized in the deep venous system appear:
With the background accompaniment of the disease (varicose veins), frequent relapses are observed each time, aggravating trophic changes in tissues and disruption of the circulatory process. If there are obvious symptoms of thrombophlebitis, it is not advisable to postpone treatment.
The main threat is purulent complications in the form of phlegmon, abscess or sepsis. As well as the development of thromboembolism. The outcome can be expressed in two ways - obstruction of small blood vessels or blockage of vital arteries, which leads to mortality.
The effectiveness of treatment depends on accurate diagnosis, which includes:
Treatment is based on an integrated approach combining medical and surgical techniques.
The method of conservative treatment of thrombophlebitis includes:
If conservative therapy fails, radical and minimally invasive surgery is used.
All these methods are quite effective. Allow patients to return to a normal, pain-free life.
Compression garments for thrombophlebitis
The gold standard for the treatment of thrombosis during pregnancy is compression garments. Its wearing is due to the effect of squeezing the superficial venous system, causing an increase in pressure in it, which improves venous outflow.
A varicose area compressed by tights or stockings will not allow a blood clot to settle in it, which will sharply reduce the risk of developing inflammatory reactions and the formation of thrombosis.
When using compression garments, swelling and cramps are eliminated, the legs practically do not get tired and pregnancy is not complicated in any way. Pregnant women are recommended:
To avoid swelling, it is not recommended to consume large amounts of liquid and drugs that affect the vascular system (phlebotonics). The selection of compression garments for thrombophlebitis should be carried out on the recommendation of a doctor, taking into account the type and degree of compression of the products.
From this article you will learn about the appearance of a blood clot in the leg: symptoms, why it occurs, and what types of treatment are used. Complications of the disease and prognosis for life.
The concept of “thrombus in the leg” includes several types of diseases, their basis is the formation of a clot in the vessels. There are:
Venous thrombosis is characterized by the formation of a clot “in situ”: under the influence of causative factors, a blood clot forms on the vessel wall, which can disintegrate into fragments and migrate through the vessels.
Arterial thrombosis is characterized by the migration of a clot from large vessels to small ones, where they completely block the blood flow.
The principles of thrombus formation are the same for the entire vascular system, regardless of the location of the clot (limbs, heart vessels, etc.).
Blood clots on the legs, depending on the type of affected vessel, have different clinical manifestations:
The danger comes from clots in the arteries and deep veins. Disruption of blood flow when the artery is turned off leads to loss of a limb if blood flow is not restored within 1–1.5 hours (depending on the time of year). Asymptomatic and mobile clots in the venous vessels are the cause of blockage of the pulmonary arteries. Impaired blood flow in small branches leads to inflammation of the lung tissue, and complete shutdown of large trunks is the cause of sudden death.
Pathology is treated by vascular surgeons (angiologist, phlebologist), and in regional centers by general surgeons.
Complete cure is possible for blood clots in the arteries and deep veins of the legs; thrombophlebitis against the background of varicose veins is prone to frequent relapses. The causes, symptoms and treatment of all types of blood clots in the legs are discussed in detail below.
Considering the mechanisms of formation, the reasons for the formation of clots in the arterial and venous beds differ.
Disorders of the development of venous valves in the prenatal period
Compression of large venous trunks from the outside (pregnancy, volumetric processes in the pelvis, enlarged lymph nodes)
Severe forms of dehydration (infectious processes, alcohol abuse);
Oncological diseases (typical for tumors of the pancreas, stomach)
Taking tablet contraceptives
Infectious and inflammatory processes in the structures surrounding the vessel
The formation of clots in the venous system of the lower extremities rarely occurs for one, isolated reason, more often the factors act together.
Group of reasons and more detailed description:
Infectious and inflammatory lesions of the inner lining of the heart (endocarditis)
Valve defects, especially after surgical correction
Signs of a blood clot in the leg depend on the type of vessel and the degree of blockage in its lumen. In case of incomplete disruption of blood flow in a vein, there are no clinical manifestations; only the complications of the disease that arise allow one to suspect and diagnose the pathology. Thrombosis of an arterial vessel is always accompanied by specific symptoms.
Excluding the asymptomatic course, the presence of a clot in a vessel has a number of characteristic signs.
3rd degree: pronounced swelling of tissues, their necrosis.
Severe pain when touched
Redness of the skin over the vein and surrounding tissues
Damage to the iliofemoral region:
With atherosclerotic lesions of the lower extremities, 70% of patients have no clinical manifestations for a long time. 20% note the progressive nature of the pathology with a gradual disruption of the usual quality of life. In 10%, arterial thrombosis ends in limb amputation.
In 90% of cases, thrombophlebitis is a complication of varicose veins, the remaining 10% occur due to the formation of clots in the deep veins and are post-traumatic. General health does not suffer. Thrombophlebitis associated with chronic insufficiency of venous circulation often recurs and is complicated by the transition of thrombus formation to the deep veins.
The formation of clots in the deep veins, associated with the short-term effect of a causative factor (surgery, pregnancy, etc.), is curable with timely treatment. Hereditary and chronic causes (thrombophilia, cancer) lead to relapses of the disease, a high risk of massive damage to the blood vessels of the lung tissue. With thrombosis of the vessels of the lower leg, the general state of health remains satisfactory. The formation of clots in large veins of the femoral and pelvic region accompanies a serious condition from the first hours. Every year, 1 person per 1000 of the world's population dies from blood clots in the vessels of the lungs.
What a blood clot usually looks like on a leg: its composition is a mixture of platelets, fibrin fibers, white and red blood cells. The loose mass of formed elements is prone to disintegration in the first 10 days of formation (maximum risk of clot migration along the vascular bed), after which connective tissue fibers develop in the thrombus, and it grows tightly to the vessel wall.
Externally (from the outside), the thrombus is not visible in any way, because it is located inside the vessel.
The diagnostic standard for suspected blood clots in the legs includes:
If damage to the deep venous vessels of the leg is suspected, a series of tests are performed, during which pain is noted (maximum dorsiflexion of the foot, circular pressure in the lower part of the leg, etc.)
Coagulogram: increase in fibrinogen level, shift in indicators towards increased coagulability
Determination of increased D-dimer: a specific marker of thrombosis
Solving the question of the possibility of endovascular treatment
Any thrombosis must be treated in a surgical (vascular) hospital. Timely and complete therapy leads to the resorption of clots. Complete cure is possible in the absence of a primary circulatory disorder and a good response to treatment. With chronic insufficiency of vascular function (arterial or venous), there is a high risk of disease relapse.
What is done for therapy:
In the absence of a chronic disturbance of blood flow in the vessels of the legs, 70–80% of patients achieve complete recovery; the rest develop postthrombotic disease in the first year after recovery, requiring further treatment.
Pulmonary artery block occurs in 20% of patients, and in 3–5% it is fatal.
Thrombosis as a complication of chronic vascular insufficiency often recurs, and complete cure is impossible. Therapy includes ongoing prevention of clot formation.
The group of vascular diseases includes thrombosis of the veins of the lower extremities. Oxygen-poor blood flows from the extremities to the heart. When blood flow slows, blood clots form, which can clog veins and cause specific symptoms.
Venous thrombosis of the lower extremities is an acute disease of a non-infectious nature, characterized by thickening of the blood and the formation of blood clots. The latter are dense clots that are firmly attached to the inner wall of the vessels. The first days the blood clots are unstable. There is a risk of their separation and blockage of the main veins (pulmonary trunk).
This can cause a person's death. More than a billion people from all over the world have risk factors for developing thrombosis, but not everyone gets it. The annual incidence of this disease is 160 cases per 100 thousand people. About 240 thousand patients are diagnosed annually in Russia. Vascular thrombosis is predominantly a disease of women.
The reason is lifestyle and hormonal characteristics. Thrombosis is rarely detected in children and adolescents. This is possible after abdominal surgery. This disease mainly affects people over 40 years of age. The risk group includes obese people whose weight exceeds the norm. The concept of acute thrombosis should not be confused with the simple formation of blood clots.
Every person constantly forms blood clots in the body, but they do not cause blockage of blood vessels and quickly resolve. Thrombosis of superficial and deep veins is distinguished. The last option is the most dangerous, because detached blood clots can enter the main veins. Very often this pathology is combined with phlebitis. This is inflammation of the vein wall.
The causes of blood clots and vein blockage can be external or internal. The following reasons for the development of superficial thrombosis of the lower extremities are identified:
Risk factors for the development of superficial thrombosis of the lower extremities include: old age, compression of blood vessels, a lying, standing or sedentary lifestyle, hypokinesia (lack of physical activity), occupational hazards (working while standing in one place), insufficient fluid intake, dehydration, acute or chronic diarrhea, bed rest, use of diuretics, use of hormonal contraceptives, alcoholism and smoking.
Acute thrombosis often develops in patients with diabetes mellitus, allergic pathology and systemic vasculitis. The causes of damage to the deep veins are due to insufficiency of the valve apparatus, congenital underdevelopment of the internal and muscular walls of blood vessels, and varicose veins.
Impaired blood clotting is possible due to cancer, hormonal changes, obesity, difficulty moving due to paralysis or paresis of the legs. Stagnation develops during long flights and transfers. The risk group includes bedridden patients, the elderly and blind people, people who stand or sit in one place for a long time (truck drivers, salespeople, consultants, pharmacists, doctors, security guards, operators).
Acute thrombosis often occurs unnoticed by the patient. This is its danger. With superficial thrombosis of the lower extremities, the following symptoms are observed:
If the cause of thrombosis is varicose veins, then the altered vessels can be identified visually. Due to the overflow of the vein with blood, the vascular wall can be determined. It has a blue tint. During palpation, it is often revealed that the affected vein does not collapse when pressed. Its color does not change, whereas normally in a healthy person it turns pale.
The general condition of patients most often does not change. If superficial thrombophlebitis develops, severe pain appears. Swelling occurs in the affected area. Most often they are localized in the ankle area. Thrombosis in combination with inflammation is manifested by fever and deterioration in general health. As the disease progresses, the veins may become swollen.
If there is deep vein thrombosis of the lower extremities, the symptoms are always milder. This is due to the fact that the vessels are located far from the surface of the skin. Patients often have the following signs of the disease:
Symptoms of venous thrombosis of the lower extremities include increased body temperature. This is observed with the development of phlebitis. The peculiarity of pain with deep thrombosis is that it is felt along the inner edge of the limb. Most often, only one leg is affected. In some people, deep thrombosis develops against the background of superficial thrombosis. This is a more dangerous condition.
A distinctive sign of deep thrombosis from subcutaneous thrombosis is that swelling can appear in different places. It is possible to enlarge the entire limb. Fresh blood clots are unstable, and they can break off and enter the general venous bloodstream. This can cause pulmonary embolism (PE). In this situation, shortness of breath, tachycardia, chest pain, intestinal dysfunction appear, bulging of the veins near the neck, and arterial hypotension are observed.
Sometimes patients are bothered by hemoptysis, fever, and vomiting. Thromboembolism can lead to fainting, coma and even death of the patient. If a blood clot is suspected, hospitalization is necessary. If the pulmonary artery is blocked, emergency care is needed.
Before treating thrombosis of the lower extremities, a comprehensive examination of patients is required. The following studies are needed:
Doppler ultrasound is the most informative. It reveals the following changes in the veins of the legs:
The study is carried out on both legs. With unilateral lesions, differences are revealed between the movement of venous blood in the left and right extremities. Often a dye is injected into the affected vein. This test is called contrast venography. Thrombosis reveals a defect in the filling of the vessel. The contrast penetrates poorly or does not penetrate the vein at all.
Narrowing of the lumen and uneven contours are often detected. In the image, blood clots are identified as rounded areas fused to the vessel wall, without contrast. When deep veins are blocked, positive functional tests are determined (marching, Loveberg, Homans, Pratt). In case of thrombosis of superficial veins of the legs, Brodie-Troyanov-Trendelenburg and Hackenbruch symptoms are detected. The results of a survey and examination of the patient are of great importance in making a diagnosis.
Not everyone knows how to treat thrombosis. Often patients are hospitalized and undergo surgery. Radical treatment is used when complications develop and in the case of floating blood clots, since there is a high probability of their breaking off. The most frequently performed operations are:
Deep vein thrombosis must be treated with complete rest. It is necessary to limit physical labor. This is necessary in order to fix the blood clot. The duration of bed rest varies from 3 to 12 days.
For superficial and deep thrombosis of the veins of the lower extremities, treatment involves the use of anticoagulants, antiplatelet agents, thrombolytics, enzyme preparations, NSAIDs, drugs that improve blood flow and increase the tone of the veins.
The treatment regimen includes Heparin, Warfarin, Fragmin. In case of acute thrombosis, it is possible to use thrombolytics (Streptokinase, Urokinase). If the patient has varicose veins, Detralex, Venarus, Troxevasin or Phlebodia-600 are indicated. They strengthen the walls of veins and increase their elasticity. To eliminate inflammation and pain, NSAIDs (Diclofenac) are indicated.
Symptoms and treatment are interrelated. If the temperature rises, antipyretics may be prescribed. All patients are prescribed a diet. The diet should be dominated by foods rich in vitamins and microelements (citrus fruits, fresh vegetables, berries, cereals, nuts, herbs, seafood, fish, fresh, lean meat). Prevention of thrombosis consists of changing lifestyle (increasing activity), avoiding fatty foods, alcohol and cigarettes, treating varicose veins, and avoiding injuries.
Thus, thrombosis is a dangerous condition. It is possible to prevent it by adhering to the right lifestyle. If varicose veins have developed, then this disease must be treated promptly.