Thrombolytic therapy is a type of pharmacological therapy aimed at restoring blood flow in a vessel due to lysis of a blood clot inside the vascular bed.
Content
Principle of Operation
Activation of fibrinolytic blood activity due to the transfer of plasminogen into its active form - plasmin.
Preparations for thrombolytic therapy are called thrombolytics, fibrinolytics or plasminogen activators (synonyms).
Unlike heparins , which only slow down the formation of thrombotic masses, this therapy contributes to their destruction and restoration of blood flow through clogged vessels.
Thrombolytic therapy is most effective up to 3 hours from the formation of a blood clot.
History
The prerequisites for the development of this type of therapy appeared in 1933 , when a daughter dies in the hands of a Tillet WS doctor. Even then, he was able to connect the illness of his daughter with non-clotting blood in a Petri dish in which she spat sputum. In 1938, the allocation of the streptokinase enzyme by Ξ²-hemolytic group A streptococcus was proved. In 1940, the mechanism of action of the enzyme was described, based on its binding to plasminogen in the blood, leading to its translation into the active form - plasmin .
1976 is considered the year of birth of thrombolytic therapy, when the article by E. Chazov on intracoronary thrombus lysis using Streptase was first published. Later, in 1979 , this data was confirmed by Rentrop KT
The main disadvantages of streptokinase:
- its foreignness to the human body, and, consequently, a large number of allergic reactions
- short half-life , which requires a long (within 60 minutes) of its introduction
- nonspecific plasminogen activation - a large number of hemorrhagic complications and depletion of the anticoagulant system.
All of these factors led to the development of new tools that do not have these shortcomings.
Thrombolytic Agents Used
To date, the following agents are known [1] :
1st generation drugs:
- Streptokinase (SK)
- Urokinase (UK)
2nd generation drugs:
- Alteplase (tissue plasminogen activator, Aktilize, t-PA)
- Prourokinase (Purolase, u-PA, pro-UK)
3rd generation drugs:
- Tenecteplase (Metalysis, TNK-tPA)
- Retaplase (Retavase, r-PA)
Applications
- Acute coronary syndrome ( myocardial infarction ) with an ST segment elevation on an ECG
- Ischemic stroke
- Pulmonary embolism
- Deep vein thrombosis of the lower extremities
- Cardiac valvular thrombosis
Notes
- β Maksimenko A.V. Cardiological biopharmaceuticals in the concept of directed drug transport: practical results and research prospects. ACTA NATURAE. - 2012. - Volume 4. - No. 3. - S. 76-86.