State, when due to the termination of circulation in one of the sections of the heart, of the tissue of the heart muscle dies, is called a heart attack. Cell death starts, if the blood flow is completely blocked for 15 minutes. This condition is accompanied by severe pain. Method of immediate relief for myocardial infarction after the diagnosis - thrombolysis.
Causes of heart attack
The most pressing dynamics in the heart attack happens in apparently healthy patients with no previous history of heart problems. Regular heart starvation due to angina, for example, train this muscle, stimulates the formation of new blood vascular, can become an additional source of supply of tissues with blood.
One of the reasons for the cessation of the blood supply to the heart leading to heart attack, thrombosis. If the arteries there is even a small plaque rupture leads to thrombus formation - accumulation of platelets. This clot and blocks blood stream, leading to disaster.
As the muscular pump, Contracting rhythmically and in a coordinated manner, the heart pumps the blood throughout the body. If one of the sites has ceased to perform its functions, was killed during the attack, the cuts may not be strong enough or stopped altogether. Too slow movement of blood leads to congestion, seepage through the walls of blood vascular in organ tissue, causing pulmonary edema.
If the lesion of the infarction is extensive, the heart muscle can not withstand the load and break, without immediate surgery, the patient will die.
The symptoms of a heart attack
blockage of the arteries of the heart
When a patient experiences a heart attack crushing pain, a burning sensation behind the breastbone. Given the pain in the upper jaw, left arm, under the shoulder blade on the left side of the back. Available suffering from heart diseases nitroglycerin, does not stop the pain.
Sometimes the condition causes no symptoms, in other cases, they indirectly indicate the cause of the problem - swollen lower leg, shortness of breath and fear of death.
Diagnosis of heart attack
The main symptom for heart attack is severe pain does not stop after taking nitroglycerin. The condition can be identified by the ECG, but in most cases necessary for comparison with earlier records. A blood test allows you to see the substance, which in the normal state in the patient's blood is negligible, and the death of area of heart leads to their massive entry into the bloodstream. Heart ultrasound also allows us to identify dead tissue, but not the time of their death.
Treatment for heart attack
The goal of therapy is to restore circulation, cessationoxygen starvation of the myocardium. Needed and immediate pain relief as the pain really bothers patients when heart attack, sometimes causes confusion.
To restore circulation, apply the following:
- intravenous vasodilating agent (nitroglycerin);
- administered anticoagulant that contribute to the resorption of blood clot - thrombolysis.
Read more about the resorption of blood clots
Elimination of the thrombus restores blood flow to the vessel. If thrombolysis is performed in a timely manner, while a fresh thrombus, it can prevent the death of a large part of the heart muscle cells. Drugs that can dissolve the blood clot are injected into the vein, the infusion rate is minimal. The most common drug is streptokinase, but its repeated administration is undesirable due to possible allergic reactions. There are more expensive drugs, which is thrombolysis: tenecteplase, alteplase.
Effective and thrombolysis in ischemic stroke, the therapeutic window when the diagnosis is 3-4.5 hours.
The mechanism of action of absorbable drugs
Thrombolysis is approved for this drugs that facilitate the transformation of plasminogen to plasmin. The purpose of the procedure is the liberation of the channel of the artery, restoring its passing ability.
Earlier in cardiology was considered a success, the minimum patency of the vessel, now - thrombolysis should lead to the normal blood flow to the restriction zone of the infarct, preserving left ventricular function and a favorable prognosis for the patient.
Cardiologists prescribing thrombolysis, warned that very important first hour after closing clot artery during a heart attack. If during this time you start to enter trombolitik, it is possible to avoid immediate mortality and deaths during the first year after myocardial infarction. Thrombolytic therapy can avoid the rupture of the septum between the ventricles, ventricular arrhythmias, cardiogenic shock.
Started on for an hour thrombolysis, called early, the most effective. The time during which it is possible to save myocardial tissue - 1-3 hours. Thrombolytic therapy initiated for 3-6 hours is not so effective, but also reduces mortality. Even after 6-12 hours thrombolysis is not considered useless.
Especially if the pain persists. Particular importance is given to this procedure in front heart attack when ECG shows extensive damageof the myocardium. It is proven that thrombolysis affects survival in myocardial infarction, regardless of age.
Studies have accumulated enough data to conclude the following: late thrombolysis, restoring perfusion, has a positive effect on left ventricular function that improves survival. And the reason is not only the restriction zone, which is covered during a heart attack, and healing of the myocardium, its contractility, the bypass flow.
The heart area is not subject to critical stretching, less likely to have arrhythmias. In the so-called sleeping condition of the myocardium when its contractility is reduced, and the throughput is almost absent, it is possible to eliminate the stenosis.
The history of the use of thrombolytic therapy
The first report illustrating the effectiveness for survival, which showed thrombolysis was made in 1981. In the group of patients, where in the first hour from the onset of symptoms was used dissolving blood clots therapy, mortality decreased by 51%. If thrombolysis had begun for 1-3 hours, mortality decreased by 25%, 3-6 hours - 18%.
Later the results of the studies continued to accumulate and summarize. Treatment of more than 100 thousand patients showed a reduction in mortality of 10-50%. Thrombolytic therapy showed restoration of patency of the artery, limiting dead zones, preservation of the pump function of the left ventricle, reduce the number of cases of complications such as aneurysms, increasing the electrical stability of the myocardium.
Indications for therapy
Testimony, which is assigned to thrombolysis:
- likely a heart attack with severe angiogram syndrome for half an hour;
- blockade of conductive system of the heart (particularly left bundle branch block);
- the absence of contraindications.
Usually the interval between onset of symptoms and therapy - 12 hours.
Contraindications to the implementation of the lysis of blood clots
- internal bleeding that occurred in the last two weeks;
- high blood pressure greater than 200/120 mm Hg. post;
- traumatic brain or other injury, surgery in the last two weeks;
- a peptic ulcer in the active state;
- suspected pericarditis (bleeding in pericardial area), the threat of aortic aneurysm;
- Allergy to the drug with which it is planned to conduct thrombolysis.
- any operation or traumatic brain injury that occurred more than two weeksago;
- hemorrhagic diathesis (tendency to bleeding) as a response to thrombolysis;
- diabetes mellitus;
- liver or kidney failure;
- malignant tumors;
- the presence of active infection;
- the use of anticoagulants in the last six months.
How do we assess the effectiveness of therapy
Coreografia shows that thrombolysis is not in the form of a dry layer and a gradual decrease of the thrombus, and the emergence in it of holes. Simultaneously, the recovery process of a blood clot. Therapy is effective when thrombolysis is faster than restoring. In some patients when heart attack may experience repeated thrombosis.
giving the thrombolysis in the prehospital
Evaluation of effectiveness is possible through the analysis of blood, ECG. Positive dynamics is the reduction of pain. An hour and a half after the beginning of thrombolysis, angiography is performed. In most cases, it shows an increase in the patency of the affected coronary artery.
Thrombolytic therapy is assessed on a scale developed to assess the effectiveness of showing the recovery of blood circulation:
- degree 0 - the contrast is not visible below the site of thrombosis, blood flow is absent;
- grade 1 - a contrast substance penetrates only partially, a weak blood flow there, but it does not fill the channel of the artery;
- degree 2 - the contrast agent passes through the vein, blood flow is, but he slowed;
- degree 3 - the contrast material completely fills the lumen of the released artery patency is considered to be restored.
Effective thrombolysis depends on several factors. Chief among them is the early initiation of treatment and mode of administration.
The author of the article: Alex Burmistrov - cardiologist, specialist in the field of cardiovascular system.