Venous thromboembolism (VTE) is a disease that involves both: deep vein thrombosis and pulmonary embolism. It is often a fatal condition that affects both patients in the hospital and those non-hospitalized. Often repeated, often overlooked and can cause long-term complications including chronic bronchial pulmonary hypertension and post-thrombotic syndrome.
Venous thromboembolic disease is a result of a combination of inherited and acquired risk factors, known as thrombophilia or hypercoagulable states – states with increased susceptibility to blood clotting and blood clots (thrombus). Arterial and in particular venous thrombosis occur under certain conditions. Over a hundred years ago Rudolf Virchow described triad of factors that are thought to contribute to thrombosis. This triad remain the basis for the understanding of the formation process of thrombosis.
Virchow’s triad:
1. Injured vessel walls
2. Cessation of blood flow, the stagnation of blood in the veins
3. Change in blood coagulation, i.e. increased activation of clotting factors
Thromboembolism is a multifactorial disease, in which multiple factors contribute to the formation of blood clot. Among the risk factors for thromboembolic disease are:
- Higher age
- Smoking
- Obesity
- Long-term immobility
- Oral contraceptives and hormone replacement therapy
- Cancer
- Operation
- Bone fractures of the legs
- Pregnancy
- Polytrauma
- Varicose veins
- Heart Failure
- Arrhythmias (atrial fibrillation)
Thromboembolism and its consequences
After the formation of a blood clot in a vein or artery, its release can follow resulting in embolization according to the original location of clots:
- It can affect the lungs causing a pulmonary embolism.
or
2. It affects the brain causing a stroke.
Both of these complications are life threatening. Embolization may cause also an acute arterial or venous closure.
Venous thromboembolic disease is a major problem worldwide, causing more than half a million deaths every year in the European Union.