Thrombolysis: Description, Where It Is Used, Indications And Complications

2024 Author: Josephine Shorter | [email protected]. Last modified: 2023-12-16 21:43

Thrombolysis: indications and complications

The vessels of the human body are subject to aging in the same way as other tissues. The metabolism slows down, due to age-related changes, blood clotting increases. The presence of somatic diseases exacerbates the situation. As a result, an elderly person develops thrombosis - the formation of blood clots in the vessels that completely or partially block the blood flow.

A thrombus can provoke myocardial infarction, stroke or cerebral infarction, other equally serious problems. To provide such a patient with effective help, a thrombolysis technique, or thrombolytic therapy (TLT), has been developed. The essence of the technique with which you can save a life and carry out a complete recovery is to remove a blood clot in the most radical way.

Thrombolytic drugs are used in the treatment of myocardial infarction, ischemic stroke, deep vein thrombosis, pulmonary embolism.

Types of thrombolytic therapy:

• Selective thrombolysis. A drug is injected into the pool of the damaged artery that dissolves blood clots. The method can be applied no later than 6 hours from the moment the vessel is blocked by a thrombus.
• Non-selective (intravenous) thrombolysis. The method is applied no later than 3 hours after the vascular accident.

Content:

• Thrombolysis in cerebral infarction
• Heart and thrombolysis
• Thrombolysis methods
• What is used for thrombolysis
• Complications after thrombolytic therapy
• Thrombolysis before hospitalization

Thrombolysis in cerebral infarction

A stroke, or an acute cerebrovascular accident, which causes massive neurological complications, sounds like a sentence for many patients. Until recently, in Russia, during the first month, at least 50% of patients died, most of the survivors lost their ability to work and became disabled.

In countries where thrombolytic therapy is used, mortality from ischemic stroke does not reach 20%. The rest of the patients restore the functioning of the central nervous system.

The thrombolysis procedure is not very difficult. It consists in the introduction into the vessel of special enzymes that dissolve the thrombus.

Contraindications to TLT:

• Bleeding of any localization at the time of thrombolysis, since not only blood clots of a pathological nature are subject to dissolution, but also those that have formed to protect against blood loss during bleeding.
• Aortic dissection.
• Tumors of brain tissue of any etiology.
• Arterial hypertension.
• Liver disease.
• Pregnancy.
• Hemorrhagic stroke.
• History of operations on the brain.

Thrombolytic therapy is performed for patients of any age. Some of the contraindications are relative, the most important among them is bleeding. In case of bleeding, thrombolysis is not performed.

To carry out this most important event, it is important to keep within the time allotted for TLT - 3-6 hours from the onset of the stroke. It is important to pay attention to its signs in a timely manner:

• Numbness of a limb on one side of the body;
• Articulation disorders;
• Inability to perform the simplest facial movements with the muscles of one half of the face.

The simplest test for determining the onset of a stroke is to ask the patient to stretch out their arms and say something. If he cannot do this, urgent medical attention is required, because there is not much time left to save a person!

Heart and thrombolysis

As a result of blockage by a thrombus of a coronary vessel, the patient develops myocardial infarction.

This process does not arise spontaneously, it is preceded by general violations:

• Slow blood flow;
• Reduction in blood levels of heparin and fibrinolysin, which have an anticoagulant effect;
• An increase in the content of blood clotting components;
• Ulceration of atherosclerotic plaques;
• Roughness of the inner wall of the vessel;
• Slowing down the blood flow, thickening it.

In case of myocardial infarction, to restore the blood supply to the heart muscle, it is necessary to promptly remove the blood clot that has blocked the coronary vessel. If you do not first conduct a thorough examination of the patient, the procedure is fraught with complications.

Necessary studies to determine the localization of the thrombus and clarify the site for drug administration:

• Duplex scanning;
• Angiography;
• CT (computed tomography);
• Doppler ultrasound.

Comprehensive research helps to significantly reduce the risk of complications.

In case of urgent indications, the cardiological ambulance team can perform thrombolysis in an emergency order to save the patient's life. The duration of the procedure takes from 10 minutes to 2 hours. Just as in the relief of the effects of a stroke, bleeding is the most important contraindication.

The cost of a complex of drugs for thrombolytic therapy can go up to 50-60 thousand rubles, but these costs are included in the rates of medical insurance.

Thrombolysis methods

There are two main ways to administer thrombolytic therapy:

• Systemic method - drugs are injected into a vein without taking into account the localization of the thrombus, they reach the blood clot and begin to dissolve it. To increase the effectiveness of the systemic method, a high concentration of the drug is required, which negatively affects the circulatory system.
• Local method - drugs are injected much more accurately than in the previous method, directly into the area of the vessel blockage. To do this, use a catheter moving through a vein, so the method is called catheter thrombolysis. Control over this minimally invasive procedure is carried out using X-rays. It is used even with relative contraindications.

What is used for thrombolysis

Drugs of choice for thrombolytic therapy:

• Streptokinase. One of the cheap thrombolytics, which are not very compatible with the human body, often causes allergic reactions. For effective action, a slow administration of streptokinase is required, the drug can cause hemorrhagic complications.
• Urokinase. Protein contained in small amounts in urine, tissues and organs of the human body. Has a higher cost compared to Streptokinase. When using Urokniaza, simultaneous intravenous administration of Heparin is required.
• Anistreplaza. It has a high cost, is injected by a jet, intravenous administration of Heparin is not required.
• Alteplaza. Has a high cost, provokes cerebral hemorrhage. The use of Alteplase improves patient survival.

Complications after thrombolytic therapy

The most common complication of thrombolysis is the appearance of bleeding of varying intensity, from minor to massive and voluminous. Can provoke a sharp drop in blood pressure.

Other complications:

• Heart failure, manifested by a violation of myocardial contraction;
• Hemorrhagic stroke that occurs in elderly patients, as a side effect of streptokinase;
• Rash, fever, chills;
• Various manifestations of allergy to drug components;
• Reperfusion arrhythmia - occurs in 50% of patients;
• Coronary artery reocclusion - occurs in 20% of patients.

Thrombolysis before hospitalization

Even a healthy person may show signs of impaired cerebral blood supply:

• Headache;
• Decreased vision, cognitive functions;
• Dizziness.

These symptoms are a sign of the onset of the disease, especially if they occur in older people. In order not to miss fatal changes, you need to conduct the following research:

• Duplex scanning of the carotid arteries;
• Ultrasound of the vessels of the brain;
• Examination of the coronary vessels;
• MRI of the brain (indicated for patients with arterial hypertension, diabetes mellitus, obesity, heart failure).

When the first signs of thrombosis appear, it is important to start thrombolysis in a timely manner, without waiting for the onset of a heart attack or stroke. This measure reduces hospital mortality by 17-19%, because "the disease is easier to prevent than to cure."

If thrombolytic therapy is available prior to hospitalization, it should be used. This requires qualified health workers, the ability to immediately conduct and decipher the cardiogram. Thrombolysis can be fully carried out within half an hour after examining the patient.

It is important to apply the thrombolytic therapy method no later than 3-6 hours from the onset of the first symptoms. Delay with the use of TLT will lead to the necrosis of myocardial cells and the cessation of the functioning of the cells of the medulla.

The author of the article: Volkov Dmitry Sergeevich | c. m. n. surgeon, phlebologist

Education: Moscow State University of Medicine and Dentistry (1996). In 2003, he received a diploma from the Educational and Scientific Medical Center of the Presidential Administration of the Russian Federation.