A heart attack is a sudden arisen circulatory failure of the myocardial layer of the heart, the formation of which is caused by thrombotic or spastic lesions of the vessels of the coronary segment followed by necrotizing myocardium in the trophic lesion zone.
Clinical death from a heart attack can be formed even during the first minutes from the debut of the clinical symptom complex, and the provocation of the fatal outcome in most cases is the presence of an extensive zone of myocardial infarction. According to the world statistics, acute heart attack takes the prevailing position as an etiopathogenetic factor provoking a fatal outcome in the general population of the population.
The consequences of a heart attack, as a rule, are irreversible, so early verification of this pathological condition and adequate prevention of repeated incidents are extremely important.
Causes of a heart attack
A reliable etiological factor in the development of a heart attack, as manifestations of pathological changes that occur in various cardiac pathologies, is the atherosclerotic lesion of blood vessels that supply the cardiac muscle. In cases where the metric parameters of the atherosclerotic plaque have small indices, the signs of a heart attack have a transient transient character, and with complete blockage of any segment of the lumen of the coronary vessel in the cardiac muscle, irreversible changes develop in the form of the formation of an ischemic and necrosis zone.
Partial obliteration of the lumen of the coronary vessel most often develops a heart attack at night in the form of a short-term pain syndrome in the projection of the retrosternal region. This form of heart attack clinicians describe the term " angina ", but these pathological conditions have a number of clinical differences (with a heart attack, the intensity of pain is more pronounced, lasting more than 30 minutes, not stopping by oral intake of Nitroglycerin). Thus, the main risk category for developing a heart attack is patients suffering from atherosclerotic and ischemic heart disease.
There are non-modifiable risk criteria for the development of a heart attack in the form of old age, gender, racial affiliation to the African-American race, and genetic determination. The so-called dismetabolic syndrome (increase in the level of atherogenic forms of cholesterol), decompensated diabetes mellitus, low tolerance to physical activity, prolonged intake of drugs of a group of non-steroidal anti-inflammatory drugs in high dosage should be attributed to the risk factors contributing to the development of a heart attack.
Symptoms and signs of a heart attack
The first signs of a heart attack are the appearance of a pronounced prolonged pain syndrome in the chest area, accompanied by a feeling of tightness in the chest and inability to perform full-fledged respiratory movements. In some situations, chest pain appears after prolonged pain in the area of the upper body, neck and shoulder girdle. The classic variant of the chest pain syndrome has a long-lasting character and can be blunt, aching, cutting, but more often patients describe this condition as "intense burning behind the sternum". Pain syndrome, even with a short flow can be accompanied by severe violations of the rhythm of cardiac activity, which is expressed as the appearance of sensations of interruptions in the work of the heart.
A typical course of a heart attack is impossible without the development of respiratory disorders of varying intensity, manifested in the form of progressive dyspnea, which occurs both after intense physical activity and in a state of absolute physical and psycho-emotional well-being.
The presence of such clinical manifestations as nausea and vomiting can simulate other pathological conditions that have nothing to do with the damage to the structures of the cardiovascular system, but these symptoms very often accompany the course of a heart attack. In this situation, the only criterion for conducting differential diagnosis is the lack of a connection between the appearance of these symptoms and the fact of eating. Frequent heart attacks have a very negative effect on the blood supply to the brain structures, which is why patients in the interictal period note marked weakness, inability to perform minimal physical activity and even short-term loss of consciousness.
In addition to the characteristic symptoms that indicate the development of a detailed clinical picture of a heart attack, there is a whole range of manifestations that act as its predecessors. Patients suffering from frequent heart attacks can foresee the onset of this pathological condition and take those medications with a heart attack that allow the pain syndrome to be shortened in a short time and prevent the development of complications. In each specific case, various clinical progenitor symptoms are observed, but in most cases there is a sharp increase in heart rate, insomnia and a feeling of "inner shivering".
When establishing a preliminary diagnosis of a "heart attack," the doctor should adhere to a differentiated approach to collecting anamnesis, clarifying the patient's complaints and evaluating the criteria for an objective examination, since there is a whole range of nosological forms accompanied by the development of similar clinical symptoms. Thus, with intercostal neuralgia, there is a pronounced pain syndrome in the chest, but in this situation, as a rule, there is no correlation between the development of pain syndrome and psychoemotional or physical exertion, which occurs in a heart attack. Despite the apparent differences in the symptomatology of these conditions, the most fundamental is a test with nitroglycerin, which stops the pain syndrome in a heart attack in the shortest time and does not have any effect on the pain syndrome in intercostal neuralgia.
To conditions aggravating the course of a heart attack and provoking repeated episodes of acute coronary insufficiency , provided there are no preventive measures, include: various forms of cardiac rhythm disturbance, cardiogenic shock and decompensated heart failure .
In most situations, a clear clinical picture and data of objective examination of the patient make it possible to correctly establish a preliminary diagnosis of a "heart attack" at the prehospital stage, but the data of the instrumental survey are reliable criteria for determining the cause of the development of this life threatening condition for the patient's life.
To establish the presence of ischemic damage to the myocardium as a pathogenetic basis for the development of a heart attack allows routine electrocardiographic examination, with specific electrocardiographic signs, both ischemia, and the development of irreversible necrotic changes in the myocardium. Echocardioscopy with a heart attack has practically no practical application, since in the early period of myocardial ischemia, there are no specific signs of damage to the heart muscle that have pathognomonic ultrasound sciology. The only laboratory method for diagnosing myocardial infarction as a background condition for the development of a heart attack is the determination of specific biological markers (troponins and creatine kinase), the level of which increases significantly with necrotic changes in the myocardium.
First aid for a heart attack
If the first signs of a heart attack are revealed, it is necessary to provide the patient with the maximum coordinated medical care even before the arrival of the specialists of the ambulance team, since this pathological condition is classified as rapidly progressive and prone to development of serious complications up to a lethal outcome.
The first steps to help a patient with a long acute pain in the chest region, which is the most important clinical criterion for a heart attack, is the patient's taking a single therapeutic dose of Nitroglycerin in aerosol or tablet form. In the absence of a visible positive effect in the form of arresting a pain attack and reducing the progression of dyspnea, it is permissible to repeatedly take a single dose of Nitroglycerin after 5-10 minutes.
In a situation where a heart attack develops for the first time in the patient, it is necessary to call a team of emergency medical care with subsequent hospitalization in the profile hospital, even if the pain relief syndrome at the prehospital stage is completely eliminated. Indications for the hospitalization of patients with a diagnosed pathogenetic form of a heart attack ( myocardial infarction , unstable angina, acute coronary syndrome) is a non-stopable pain syndrome and the progression of hemodynamic and respiratory disorders.
In order to eliminate the pathogenetic link of atherosclerosis and emergency lysis of the available thrombotic masses, patients in the pre-hospital stage are recommended oral Aspirin in a single dose of 500 mg. It is necessary to notify the doctor of the ambulance team about taking medicines at the prehospital stage, indicating not only the pharmacological group, but also the dosage. The composition of emergency therapy of a heart attack includes masochka oxygen therapy.
The relief of a pronounced prolonged pain syndrome in a heart attack is realized using the method of neuroleptanalgesia drugs (agents combining analgesic and neuroleptic effects). For this purpose, a 0.005% solution of Fentanyl in a dose of 1 ml should be used, as well as a 0.25% solution of Droperidol in a single dose of 2 ml by the intravenous-jet method. In a situation where intense pain syndrome is accompanied by increased excitability of the patient with a heart attack, it is advisable to use intravenous drug (1% morphine solution in a dose of 1 ml).
Treatment of a heart attack
The therapeutic measures used in a heart attack should be pathogenetically justified and etiologically directed. Drug treatment methods differ according to the principle of long-term admission. There are medicines for emergency medication correction of a heart attack, as well as for lifelong maintenance therapy.
Due to the fact that the formation of an obstruction to normal blood flow through the coronary vessels due to the development of blood clots in the lumen is the basis for the development of a heart attack, the elimination of thrombotic masses by any possible method is an indispensable condition for improving the patient's condition and reducing the risk of developing irreversible myocardial changes. The most effective method of eliminating intraluminal vessel obturation is the performance of angioplasty in the form of percutaneous coronary intervention. The effectiveness of this method directly depends on the timeliness of its use (no more than 90 minutes from the debut of a heart attack).
Numerous randomized trials have proven the absolute inefficiency and inappropriateness of the use of percutaneous coronary shunting to patients after more than three days from the debut of a heart attack. In 10% of cases after the angioplasty there is a complication in the form of restenosis, which is formed within half a year from the application of surgical treatment. In order to exclude the development of restenosis, a technique for the use of stents with a special coating (sirolimus, paclitaxel) has recently been developed. All patients who have been implanted with a stent are recommended not only in the postoperative period, but also for life to take Klopidogrel, 1 capsule in the evening.
In a situation where there is no possibility of performing an operative intervention, an alternative method is the use of an adequate scheme of thrombolytic therapy with the use of drugs whose effect is aimed at lysis of thrombotic masses and the restoration of normal blood flow. It should be borne in mind that the effectiveness of thrombolytic therapy is limited to time intervals, that is, it is necessary to use drugs of this category in the first three hours from the onset of a heart attack. Limiting factors for the use of thrombolytic therapy are: the elderly patient having anamnestic data for a stroke, pregnancy and acute massive blood loss, the patient's stomach ulcer, long-term use of anticoagulants.
In order to reduce the risk of progressing the formation of thrombotic complications, as well as preventing the formation of new blood clots, it is advisable to combine the appointment of anticoagulant and antiaggregant drugs. Currently, in terms of emergency treatment of a heart attack, Akteliz, Metaleze (100,000 to 250,000 units) is used. The most severe and frequent complication of the use of drugs of this pharmacological group is the development of hemorrhagic type of stroke.
In order to stimulate protein synthesis and improve metabolic processes in the body, the intensification of the scarring process in the necrotic zone uses drugs of the anabolic steroids group (Retabolil once in 10 days, 5% solution in a dosage of 1 ml, Fenobolin intramuscularly at a dose of 1 ml of 1% solution 1 time in Week). Absolute contraindications to the use of drugs of this pharmacological group are any cancer, pregnancy and severe hepatic insufficiency.
Patients who have a heart attack develop against a background of congestive heart failure, it is recommended to apply an adequate scheme of diuretic therapy with the parenteral route of administration in addition to standard medication (Furosemide intravenously 20 mg 1 -2 times a day).
Preventing a heart attack
The prognosis for a heart attack directly depends on the preventive measures that the patient applies in the post-attack period. The preventive measures used are aimed primarily at preventing a recurrent episode of a heart attack, as well as reducing the risk of developing a fatal outcome. According to statistical data, the development of acute coronary syndrome is provoked by the patient's non-compliance with the recommendations of the treating physician in full with regard to the prevention of a heart attack. In addition, provided there is no preventive treatment, a heart attack can provoke the development of severe forms of cardiac rhythm disturbance and damage to the valvular heart apparatus.
It should be borne in mind that in some situations the patient after the episode of a heart attack can develop a painless form of myocardial ischemia that is not accompanied by the formation of classical clinical symptoms and at the same time has a high risk of developing cardiovascular complications, up to a lethal outcome.
As a preventive measure should be considered dynamic monitoring of blood pressure and retention of these indicators at a level of not more than 140/90 mm Hg, for which all patients suffering from heart attacks in the presence of hypertension are recommended to take regular drugs of antihypertensive category and compliance rules for the correction of eating behavior (limiting the use of salt and compliance with the water regime). As an antihypertensive drug should be given to the group Beta-blockers (metoprolol in a daily dose of up to 200 mg orally), which are the drugs of choice in preventing the development of a second episode of myocardial infarction and heart attack. The mechanism of the positive effect of these drugs is realized by reducing the need for cardiac muscle in oxygen, reducing the heart rate.
The most recent randomized trials allow one to affirm the positive effect on the life expectancy of patients who have a history of a heart attack, the drugs of the antiplatelet group, provided they receive a regular lifelong admission (Clopidogrel, Cardiomagnin once a day, orally). In addition, the drugs of the statin group with prolonged intake level the possibility of progression of atherosclerotic vascular lesions of the coronary segment, which significantly reduces the risk of recurrent episodes of a heart attack (Atorvastatin in a maintenance dose of 20 mg for at least six months orally). When appointing patients to the category of statins should take into account their hepatotoxicity, in this connection, it is recommended that a preliminary study of the organs of the hepato-biliary system, as well as taking the drug with a constant laboratory control of liver samples.
? Heart attack - which doctor will help ? At the slightest suspicion of a heart attack, you should immediately seek advice from such specialists as a therapist or cardiologist.