Deep vein thrombosis (DVT) is a disease of the deep venous system, which is caused by complete or partial closure of vein by thrombus. The annual incidence of deep vein thrombosis of the lower limbs is estimated at 1-2 cases per 1000 inhabitants. In the first thirty years of life, deep vein thrombosis is ten times less frequent and the risk gradually increases with age. In rare cases it affects children. Occurrence, regardless of gender, but the average age at which men develop deep venous thrombosis is lower (66 years) than women (72 years). Question of seasonal incidence of DVT remains unresolved.
Risk factors for deep vein thrombosis
- Long immobility – hospitalization with bed rest, gypsum, long travel
- Injury – especially fracture of long bones
- Knee surgery or hip
- Pregnancy and postpartum
- Hormonal drugs – hormonal contraceptives, hormone replacement therapy
- Central venous catheter
- Obesity
- Sarcomas
- Lack of internal anticoagulants – protein C, protein S, antithrombin III
- Antiphospholipid antibodies
- Nephrotic syndrome
- Hyper viscosity of blood (, thickening of blood”) – increased number of red blood cells or leukocytes, elevated levels of blood proteins or dehydration
- Leiden mutation
- Dysfibrinemia
- Prothrombin gene mutation
- Homocysteinemia – mutations in the MTHFR gene
Symptoms of Deep venous thrombosis
Symptoms of DVT are usually:
- sudden swelling of limbs
- convulsive pain in the calf or pain and tenderness of the entire limb
- painful limbs with an increase in venous pressure
- pallor or cyanosis (bluish) of the limb
- numbness
- possible redness and warm skin at the site of thrombosis
Further, fever may be present or fever and acceleration of pulse rate. In rare cases there might be a positive sign of a plantar fasciitis (pain on pressure in the middle of the foot) and Homans’s sign (calf pain at dorsiflexion of the foot).
Iliofemoral thrombosis
Ileofemoral thrombosis (in the hip and thigh area) and thrombosis in the pelvic might cause creation of venous collaterals, which replace thrombosed vessel of deep vein system in the groin area or can be seen in the abdomen known as Medusa head – caput medusae. Deep iliofemoral thrombosis may manifest itself uncharacteristically, e.g. through abdominal pain. Mostly the left leg is affected. On a limb you can see formed collateral vessels. Thrombosis in the area of mediastinum may manifest by Superior vena cava syndrome with edema and erythema in the upper part of the chest, neck and face. Venous thrombosis at the site of cannulation and ports will be manifested with swelling, pain and redness in the course of blood vessels.
Phlegmasia cerulea dolens (literally: painful blue edema) is an uncommon severe form of deep venous thrombosis which results from extensive thrombotic occlusion (blockage by a thrombus) of the major and the collateral veins of an extremity. It is characterized by sudden severe pain, swelling, cyanosis and edema of the affected limb. The patient may be hypotensive (low blood pressure) or in a shock. The color of the leg can turn bluish and blood flow deteriorates even in arteries. In the subcutaneous tissue of the limb there may be bruising termed petechiae – tiny purple bruises.
Unusual symptoms of deep vein thrombosis
Warning: Deep venous thrombosis can manifest uncharacteristically. Symptoms may not fully correspond to the above-description and for e.g. may occur only swelling – relatively suddenly developed in a few days without any other symptoms – even in this case you should immediately contact a physician.
Unfortunately, it can also happen that you get to a doctor, who will not provide the correct diagnosis. If you feel that you want the opinion of another physician, find another doctor and talk to him. There were cases when the correct diagnosis and treatment was not carried out until the third doctor was consulted. Some patients, especially young people, in whom this complication is not expected, paid with their lives. Early diagnosis is extremely important.
What is the danger of deep vein thrombosis?
Deep vein thrombosis is dangerous because of the risk of serious complications like – pulmonary embolism, chronic venous insufficiency and post-thrombotic syndrome. Pulmonary embolism can lead to death of the patient, chronic venous insufficiency with post-thrombotic syndrome may lower the quality of patient’s life. It is therefore important not only to diagnose and adequately treat deep vein thrombosis, but also to focus on a thorough prevention in high risk populations.
Every thrombophiliac should learn the risk factors causing thrombosis, plan appropriate lifestyle and be actively avoiding risks.