Thrombolysis: Meaning (information, definition, explanation, facts)

Thrombolysis is the breakdown (lysis) by pharmacological means, of blood clots. It is colloquially referred to as clot busting for this reason.

Agents

Thrombolysis requires the use of thrombolytic drugs, which are either derived from Streptomyces spp. or (more recently) the effect of recombinant technology, where human activators of plasminogen (e.g. tissue plasminogen activator, tPA) are manufactured by bacteria.

Some commonly used thrombolytics are streptokinase, urokinase and alteplase (recombinant tissue plasminogen activator or rtPA).

Formation of blood clots lies at the basis of a number of serious diseases (see below). By breaking down the clot, the disease process can be arrested, or the complications reduced. While other anticoagulants (such as heparin) decrease the "growth" of a clot, thrombolytic agents actively reduce the size of the clot.

All thrombolytic agents work by activating the enzyme plasminogen, which clears the cross-linked fibrin mesh (the backbone of a clot). This makes the clot soluble and subject to further proteolysis by other enzymes, and restores blood flow over occluded blood vessels.

Diseases where thrombolysis is used:

• Myocardial infarction
• Cerebrovascular accident
• Massive pulmonary embolism