Thrombolysis and Inferior Vena Cava Filter Placement


Thrombolysis is performed when there is a thrombus that needs to be dissolved, which is accomplished by the administration of the pharmaceutical drugs that stimulate degradation of the clot.

Thrombolysis offers non invasive way to restore pulmonary blood flow in cases of pulmonary embolism. While anticoagulants like heparin stop further growth of the clot, thrombolitics actually dissolve and reduce its size.

Thrombolitic drugs work by activating plasminogen, the enzyme that is reponsible for degradation of the fibrin mesh, which supports the structure of the thrombus. In this way the thrombus is made soluble and goes through the process of further proteolysis which is executed by the other enzymes in the process of clot dissolution. This process helps restore the blood flow in affected blood vessel and decrease the possibility of further complications.

After fibrin has been broken down by the fibrin, numerous parts of fibrin mesh are released into the blood stream. These are called Fibrin Degradation Products (FDP). Some of FDPs are used for diagnostic purposes, particularly D-dimer (small protein fragment) which is used to test for DVT and pulmonary embolism.

Some commonly used thrombolytics are: Streptokinase (Streptase), Urokinase, Alteplase etc.

Wikipedia: Fibrinolysis (simplified). Blue arrows denote stimulation, and red arrows inhibition.

Wikipedia: Fibrinolysis (simplified). Blue arrows denote stimulation, and red arrows inhibition.

Inferior Vena Cava Filter (IVC Filter) is a type of vascular filter used to prevent pulmonary embolism by catching the emboli before it reaches the heart. In patients with diagnosed deep vein thrombosis part of the thrombus can detach and travel from the affected vein toward the heart causing pulmonary embolism. IVC filter is used when there is a contraindication for anticoagulant therapy (cerebral hemorrhage) or if the anticoagulation treatment proved to be ineffective. An IVC filter is catheter-guided and implanted in the inferior vena cava below the renal veins. IVC filter reduces the risk of acute or subacute thromboembolitic complications, and can be placed on a temporary or permanent basis.