Forms of myocardial infarction
Last reviewed: 07.06.2024
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Myocardial infarction is one of the leading causes of human mortality in most of our planet. Especially high mortality rates are often associated with incorrect preliminary diagnosis and, consequently, delayed therapeutic response to an acute attack. The fact is that the forms of myocardial infarction are different: they differ in their clinical picture and in many cases are "masked" under other pathologies, significantly complicating diagnosis.
Almost any medical professional (doctor, paramedic, nurse or trained paramedic) who has the ability to record and decipher electrocardiogram data can suspect one or another form of myocardial infarction. If it is not possible to interpret the results competently directly near the patient, it is necessary to provide emergency remote consultation - there is no time to lose at the time of an acute attack. Thus, the initial diagnosis should be based not only on the existing clinical manifestations, but also on changes in electrocardiogram parameters.
Why is it important to know about the forms of myocardial infarction?
Representatives of international cardiology communities have adopted a unified classification of myocardial infarction based on clinical, morphological and other features of the disease. Thus, infarction can be developing (initial period - from 0 to six hours), acute (from six hours to seven days), scarring (from 1 to 4 weeks) and healed (more than 29 days). This division is relative, but it is convenient for statistics and research work.
The preinfarction stage often occurs suddenly, without a clear prodromal period. Only when the patient is interviewed in detail, it is possible to establish that the "first bells" were still present, although they were interpreted by the patient incorrectly or were not taken seriously. Some patients with initial symptoms do not seek medical help at all, and those who do, in atypical cases receive an incorrect diagnosis and incorrect treatment. Unfortunately, the incidence of misdiagnosis is quite extensive. A common mistake is failure to perform ECG on a patient in situations requiring differential diagnosis.
Often the development of any form of myocardial infarction is preceded by angina pectoris, which suddenly changes its course dramatically. The attacks may become more frequent (sometimes they are repeated with an interval of several minutes), increase their intensity, change or expansion of the area of pain recoil (irradiation), occurrence of attacks even with little or no load. Tension angina is transformed into resting angina, there are "nocturnal" attacks. Particularly dangerous in this situation are considered prolonged (more than 15 minutes) heart pain, combined with arrhythmia, strong autonomic response, increasing symptoms of heart failure. This form of the disease is referred to as "unstable".
In some patients, the prodromal stage of myocardial infarction reveals itself by nonspecific symptoms that are not characteristic of the classical course of heart failure. For example, many patients indicate the appearance of severe unreasonable fatigue, weakness, etc. To correctly interpret such a picture is quite difficult even for an experienced specialist, and the true cause of the ailment can be suspected only after performing diagnostic electrocardiography.
There are several most common forms of myocardial infarction, about which every person, even those who have nothing to do with medicine, should know. After all, problems with cardiac activity often require urgent treatment, and delayed referral to a doctor can cause an unfavorable development of events, up to the death of the patient.
Typical form of myocardial infarction
Despite the fact that all forms of myocardial infarction are well studied, and cardiologists have in their arsenal of elaboration of all possible options for the development of events and treatment schemes, difficulties can appear against the background of rapid development of irreversible myocardial damage. To provide first aid, the medic may have only minutes. And during this time, the specialist must correctly orient in the situation and immediately suspect one or another form of infarction.
In myocardial infarction, extremely severe cardiac ischemia occurs, and the threat to the patient's life increases literally "before your eyes". There is a failure of blood circulation in the heart muscle, a zone of cell necrosis is formed. Spasm or blockage of the vascular lumen contribute to the deterioration of blood flow. Since the myocardium is the main functional part of the heart, the main load falls on it. Why does pathology develop?
None of the forms of myocardial infarction occur "out of nowhere". If a person is completely healthy, then the heart muscle does not suffer. The development of the disease is promoted:
- Vascular atherosclerosis provoking myocardial ischemia due to occlusion of a blood supply vessel;
- formation of a blood clot in a coronary vessel, with complete or partial blockage of the lumen;
- other cardiovascular pathologies, including heart defects.
In some patients, it is possible that several factors may be affected simultaneously - for example, the problem occurs when a vessel affected by atherosclerotic plaques spasm.
The generally accepted classification of the disease involves not only dividing it by forms (typical and atypical myocardial infarction). Pathology can be:
- small-focal, with the formation of several necrotic areas in the myocardium;
- large-focal (the area of tissue necrosis is single, but quite large).
There are also differences in the depth of the debridement focus (trans and intramural, subendo and subepicardial myocardial infarction).
The infarction that first occurred is called primary, the one following it is called recurrent. The third and subsequent infarct attacks are recurrent pathologies.
The different forms of myocardial infarction differ, among other things, in their clinical symptomatology.
The classic start of the infarct state is manifested by an attack of pain of appropriate localization (in the heart area, behind the sternum). The character of pain is similar to angina pectoris, but in most cases differs in intensity and duration. A typical sign of a heart attack: the pain syndrome cannot be completely eliminated with Nitroglycerin or analgesics (including narcotic drugs).
In some patients the pain is aching, not severe, but in most patients it is still intense and even unbearable.
The nature of pain: squeezing, burning, squeezing. Many patients indicate a feeling of a "heavy stone" behind the sternum. There may be "recoil" (irradiation) to the left upper extremity, left shoulder joint, neck or back (left scapula), etc. If pain is detected not in the heart area, but only in the zone of irradiation, it is most often an atypical form of myocardial infarction.
The pain syndrome may be aching, but more often it is wavy. Duration - from 20-25 minutes to several hours.
Additional possible sensations: fear, agitation, panic, anxiety, signs of autonomic nervous system (increased sweating).
Relatively rare signs are considered to be:
- isolated breathing difficulties;
- choking episodes;
- Vomiting (with or without nausea);
- pain in other parts of the body;
- sudden weakness;
- impaired consciousness, fainting;
- the sensation of your own heartbeat.
If we consider the manifestations of the typical form of the disease by stages, it will look as follows:
- Prodromal stage. In half of the cases, the attack occurs abruptly, without a prodromal stage. If it is still present, it is manifested by increased frequency and intensification of cardiac pain, deterioration of general well-being, a feeling of anxiety and fear.
- Exacerbation stage. It is characterized by intense pain attack with location behind the sternum, with possible "recoil" to the left upper extremity, shoulder joint or clavicle, or left scapula. The attack is sharp, stabbing, constant or wavy.
- Acute stage. Painful squeezing is weakening, blood pressure values fall slightly (approximately by 20%), rhythm failure is noted.
- Subacute stage. The condition gradually normalizes, the rhythm of cardiac activity is restored, breathing is facilitated.
- Postinfarction stage. With a single small focus of lesion, the signs of heart failure disappear. With a pronounced myocardial lesion, cardiac deficit progresses and worsens.
It is not easy to list absolutely all manifestations of myocardial infarction, since they can be different, depending on both the period of development of the violation and the individual characteristics of the patient. Many patients are distinguished by their own "set" of clinical symptomatology, which most often indicates an atypical form of the problem.
Atypical forms of myocardial infarction
Atypical, or unusual course of pathology requires special attention on the part of physicians, because in such a situation it is much more difficult to recognize myocardial infarction among the symptoms that are not characteristic of a classic attack.
The most common are such atypical forms of the pathologic process:
- The asthmatic form is more characteristic of recurrent myocardial infarction. The problem occurs more often in elderly patients and old people who already had chronic heart failure. It is noteworthy that in the asthmatic variant, the pain syndrome may be mild or absent, and a cardiac asthmatic attack or pulmonary edema may act as the only clinical manifestation of infarction.
- The abdominal form is predominantly observed in patients with diaphragmatic myocardial infarction. Abdominal pain and dyspepsia (nausea, abdominal bloating, other digestive disorders) are typical for this variant. When probing the abdomen, it is even possible to detect tension in the abdominal muscles. Symptomatology can falsely direct the specialist to the thoughts of acute pathology of the gastrointestinal tract, which leads to errors in the choice of therapeutic tactics. Cardiologists insist: in such a situation, before making a preliminary diagnosis, it is necessary to perform electrocardiography on the patient.
- The arrhythmic form is diagnosed if the symptomatology includes heart rhythm failures and conduction disturbances - in particular, we may be talking about complete atrioventricular block, or paroxysms of supraventricular or ventricular tachycardia. In the arrhythmic course, pain is not always present and is often mild. If severe arrhythmias appear simultaneously with a typical pain attack, then here about atypicality is not a question: the doctor makes a note of the complicated course of myocardial infarction. It is important to note that sometimes heart rhythm disorders can complicate the main diagnosis.
- Cerebrovascular form is inherent in elderly patients who initially had stenosis of intracranial or extracranial arteries, cerebral circulation disorders. Pathology reveals itself with disorders of consciousness, dizziness, accompanying nausea (sometimes - to vomiting), stroke symptomatology (developing in parallel). Cerebral ischemia can occur due to a decrease in minute cardiac volume, which is caused by a lesion of the left ventricle, or a violation of the rhythm and conduction of the heart. Sometimes the problem is provoked by thromboembolism of cerebral vessels as a result of thrombophragmentation in the left ventricle, which, in turn, is a consequence of extensive infarction. In such a situation, it is more appropriate to speak not about the primary attack, but about its complication.
- The painless form is a fairly common phenomenon, so often traces of heart muscle damage are found in the process of autopsy in patients who died for other reasons. Such a "hidden" form is inherent in people suffering from diabetes mellitus, as well as female patients, elderly patients who have suffered a circulatory disorder in the brain.
There are other atypical forms of pathology, which are particularly rare. They become a major factor in diagnostic errors and prevent the timely initiation of proper treatment of acute disease. The degree of lethality in patients with atypical forms is much higher than in people with a typical course of infarction. Therefore, physicians insist on the importance and necessity of priority electrocardiography - and this is especially true for such patients as the elderly and the elderly, persons with cardiovascular diseases and diabetes mellitus.
In any suspicion of myocardial damage, it is necessary to clarify the presence of ischemic heart disease (previous heart attacks, angina pectoris), determine the risk factors for cardiovascular diseases (atherosclerosis, arterial hypertension, bad habits, diabetes mellitus, obesity, etc.). It is also necessary to find out whether before the attack there was excessive physical or emotional stress, infectious and inflammatory diseases, injuries, etc.
Differential diagnosis is also made with pulmonary embolism, aortic aneurysm, acute pericarditis or myocarditis, pleuropneumonia, intercostal neuralgia, digestive diseases, hepatic colic, mesenteric thrombosis, stress-induced type of cardiomyopathy.
Next, we will look at some atypical forms of heart muscle pathology in more detail.
Abdominal form of myocardial infarction
Abdominal type of pathology is noted in about 1-2% of cases, and more often it is manifested by gastralgia, less often - dyspepsia. Symptomatology of this form of the disease is often found in the elderly and women. Patients, as a rule, late seek medical help, which again can be associated with an atypical clinical picture. This becomes the cause of a more unfavorable prognosis. Thus, the degree of hospital mortality in the typical form is about 13%, and in the abdominal form it reaches 50%.
Symptoms of the abdominal variant are represented by abdominal pain and/or dyspeptic disorders. As a consequence, the patient is suspected of any acute pathology of abdominal organs, wrong therapeutic tactics are applied, hospitalization in a non-core department, and sometimes even unwarranted surgical intervention is performed. An even more unpredictable situation occurs if myocardial infarction develops against the background of an acute disease of the abdominal cavity. In such a case, the risks of patient death increase significantly, both due to extensive myocardial damage and as a result of the underlying cause of abdominal manifestations: massive internal bleeding, dissecting aneurysm, etc.
Thus, medical specialists need to conduct not just emergency diagnosis, but also emergency differential diagnosis of acute myocardial infarction and acute surgical pathologies.
The abdominal form of the disease can mislead both the doctor and the patient. If a person suffers from chronic gastritis or cholecystopancreatitis, he will not be able to identify the signs of abdominal infarction. Such a patient will continue to take his usual medications, although they will not lead to relief.
The development of abdominal variant is associated with the localization of the zone of infarct necrosis in close proximity to the diaphragm. This leads to the fact that the pain begins to irradiate to the abdomen. True, after some time, pain sensations are still shifted to the sternum area, blood pressure decreases. However, by this time, precious time can already be lost.
When a patient is admitted to a surgical or infectious disease unit, even with clear signs of dyspepsia and abdominal pain, electrocardiography should be ordered to rule out the dangerous abdominal form of infarction. This procedure is mandatory, standardized and uncomplicated.
Cardiographic criteria for a heart attack may include:
- disruption or arcuate ST segment elevation, which can merge with a positive T, or even change to a negative T;
- formation of pathologically disturbed Q with decreased amplitude of R, and in some cases - complete loss of R with formation of QS;
- formation of negative T plaque, often with symmetrical localization.
An indirect manifestation of the development of acute circulatory failure in the myocardium may be acute Hiss bundle branch block. Additionally, markers of cardiac muscle damage are detected. The level of troponin in the blood is significantly increased (initial 5 hours from the moment of infarction and further up to 12 days). Among the diagnostic procedures of the auxiliary order, echocardiography is possible.
Gastralgic form of myocardial infarction
One of the variants of the abdominal form of pathology - gastralgic infarction - is noted predominantly with posterior (diaphragmatic) myocardial damage. The problem is manifested by severe pain in the epigastric zone, less often - in the right subcostal area. The pain syndrome can be accompanied by nausea (with or without vomiting), frequent liquid stools. In some patients there is gastrointestinal bleeding associated with the formation of a stress (acute) mucosal ulcer. Palpation of the abdomen reveals pain in the epigastrium, local manifestations of peritoneal irritation.
All patients with acute abdominal pathology should undergo an electrocardiography procedure! If available, doctors compare the electrocardiogram taken at the time of the attack with the cardiogram taken earlier. It is important to understand that the final diagnosis of infarction is made by a series of ECGs, since in many cases infarct signs are manifested only a few days after the start of the pathological process.
Among additional diagnostic methods, the following procedures may be used:
- Echocardiography is a two-dimensional study that records local contractility disorders of the heart muscle and allows to assess the degree of spread of the pathological process, the quality of contractile function. In addition, it is possible to detect wall thrombi in cardiac cavities, areas of vascular dissection, ruptures or pericarditis, as well as to differentiate infarction from thromboembolism, dissecting aneurysm, hypertrophic cardiomyopathy.
- Radioisotope myocardial scintigraphy helps to determine the presence of acute infarction when the mass of necrotized tissue is not less than 3 g. The effectiveness of the method is due to the ability to accumulate the substance only by viable heart muscle, and the absence of such accumulation in the focus of necrosis.
- Positron emission tomographic study - involves the use of short-lived isotopes and helps to determine myocardial perfusion at different sites, clarify viability and find necrotized and ischemic foci.
- Daily ECG monitoring - prescribed to monitor rhythm and conduction abnormalities.
If the patient has pain in the epigastrium, the doctor must necessarily make a differential diagnosis with gastralgic form of myocardial infarction, and with diseases of the esophagus and the digestive tract in general, with pneumonia and diaphragmatic pleurisy. If the pain extends to the right subcostal area, it is necessary to exclude also liver and gallbladder disease, pleuropneumonia, subdiaphragmatic abscess.
Anginoid form of myocardial infarction
One of the basic signs of myocardial infarction is a pain syndrome with localization in the chest, behind the sternum, in the heart area. Most often we are talking about intense (sometimes - very strong), squeezing, cramping, baking pain. The most common pain zone: the sternum, or to the left of it (it can also be on the right, but much less often). Irradiation to the lower jaw, neck and throat, back (left scapula and interscapular area), upper abdomen is possible. The character of the pain syndrome is extensive, diffuse, not limited and not point. More typical is a wave-like course, with periodic increases and easing, resumption and disappearance. Duration of the angina period - from 15-20 minutes to several hours.
Angina form of myocardial infarction is represented by this main sign - pain. Other background symptoms are also possible - severe weakness, increased sweating (cold, sticky sweat), tremor and chills, feeling of shortness of breath, coughing (associated with dyspnea), dizziness and disorders of consciousness. However, among these many signs, pain occupies a special place: patients report it first.
Due to the intense pain sensations, the patient may become emotionally agitated, his behavior changes. Psychosis may develop.
The listed pathological manifestations can be combined with each other, or absent. However, chest pain in the anginoid form of pathology is the main, dominant symptom that appears due to acute oxygen deficiency of the myocardium or its limited area, which is most often a consequence of stenosis or blockage of the artery with a thrombus or atherosclerotic plaque.
Angina pain is not just a painful sensation. It is characterized by intensity and burning sensation. There is a feeling that the heart is squeezed and squeezed, and there is a big heavy stone on the chest: this is how many patients describe their condition. At the same time with such pain, there is shortness of breath and a special, inner fear - a person feels the possibility of death.
A typical gesture of a patient with an anginous form of attack - the palm of the hand is pressed against the heart area. Such a state in myocardial infarction can last at least 20-30 minutes. At this time, it is necessary to correctly orient and immediately take the patient to a medical institution, or otherwise provide assistance from a cardiologist, therapist, paramedic.
The patient is urgently referred to a cardiac intensive care unit, where measures are taken to restore adequate blood circulation, limit the spread of tissue necrotic changes, prevent the development of complications. Bed rest, round-the-clock monitoring of cardiac activity, medication support with the use of thrombolytics, anticoagulants, antiaggregants, beta-adrenoblockers (prescribed individually) is mandatory. After stabilization of the patient's condition, he is transferred to the cardiology department of the hospital, where he will stay for 2-3 weeks. This period can be different, which depends on the presence and absence of complications, the size and location of the pathological necrotic focus, the general condition and age of the patient.
According to statistics, the anginosis form is diagnosed most often, which is due to the intense and typical symptomatology of the attack. It is important to pay timely attention to a sharp deterioration in the patient's well-being and provide immediate medical intervention. The speed of care is the key to a favorable outcome for both health and life.
An "emergency ambulance" should definitely be called if:
- the angina attack was the first time
- pain increases and lasts more than 5-10 minutes, accompanied by respiratory distress, nausea, increased sweating, severe weakness;
- pain does not stop after swallowing a tablet of Nitroglycerin, or even intensifies (for 5 minutes).
If taking Nitroglycerin led to the disappearance of heart pain, the patient also needs to perform electrocardiography to find out the cause of the problem (possible coronary spasm, etc.).
The response to an attack should be prompt, without delay.
Asthmatic form of myocardial infarction
Among the many atypical forms of myocardial infarction, one of the most dangerous and unpredictable is considered to be the asthmatic variant. In infarction, the heart muscle is no longer supplied with oxygen in the volumes necessary for adequate vital functions. For this reason, foci are formed in the myocardium, in which the tissue dies off. In many cases, this pathological process is accompanied by typical manifestations, but in some cases, infarction is "masked", "hides", pretending to be other pathologies, which "confuses" both the patient and the medical specialist. In elderly people, as well as in persons who are often exposed to stress, often occurs dangerous asthmatic form of acute attack. What is it dangerous? Not only the development of a massive heart attack. The problem can grow into the development of cardiac asthma and pulmonary edema: as a consequence - lethal outcome. Such a form is manifested by atypical symptoms: a suffocating attack, cough with the formation of thick foamy sputum of pinkish color.
Chest pain characteristic of infarction is not noted. Symptomatology fully resembles a bronchial asthma attack: severe breathing difficulties, deep cough with sputum. Deterioration of the condition is usually combined with a decrease in blood pressure, heart rhythm disturbance. Sometimes a "gallop" rhythm is observed. Most often, the asthmatic form is diagnosed in patients who have previously suffered a myocardial infarction. Usually these are elderly and elderly patients, especially often - persons with previous chronic heart failure, repeated heart attacks. Heart pain may be absent at all, or be of low intensity. At the same time, an episode of cardiac asthma or pulmonary edema becomes the initial and sometimes the only clinical sign of myocardial focal necrosis.
In patients with the classic form of pathology, the pain syndrome in the heart area is usually so pronounced that the problem is impossible not to notice and relatively easy to identify. In the asthmatic form, pain recedes into the background, or is not noticeable to a person at all, which is not the case with the symptomatology of an asthmatic attack. This "veiled" variant often leads to diagnostic errors and becomes the reason for the delayed start of proper treatment. Lethality in this group of patients is certainly higher than in patients with typical infarct clinic. To avoid errors in diagnosis, it is very important to qualitatively and timely examine people coming in with such symptoms. It is necessary, first of all, to perform electrocardiography and promptly perform differential diagnosis with all similar diseases.
The clinical picture of asthmatic form of myocardial infarction is due to pulmonary stasis of blood. Pathology is dangerous and can become the cause of sudden death, so it is important to contact a medical specialist at the first pathological signs. The main manifestations to which attention should be paid:
- prolonged exhalation and difficulty in inhaling air, resulting in obvious discomfort and severe shortness of breath (the person literally suffocates);
- The shortness of breath is accompanied by a persistent, agonizing cough;
- the skin is pale;
- protruding veins in the neck;
- profuse sweating appears (sweat is sticky, cold);
- noted lividity of the nasolabial triangle, fingers of the upper extremities.
If the infarction develops during the night, the patient wakes up abruptly because of increasing breathing problems. This can be the cause of a panic attack. Often a person rushes to the window, trying to "breathe" air, although such actions do not alleviate his condition.
The onset of a seizure is often preceded by:
- psycho-emotional stress;
- general fatigue;
- overeating before bed;
- increased blood pressure.
What should be done when an asthmatic form of infarction develops:
- to call the emergency room;
- Open a window in the room, unbutton the patient's clothing to facilitate air access;
- help the person to take a comfortable position (put pillows or a rolled-up blanket under the back, lower the legs below body level);
- remove accumulated foam (if any) from the mouth;
- put a tablet of Nitroglycerin under the patient's tongue.
Asthmatic form is a dangerous variant of pathology, so recognizing the problem should be paid special attention, carefully monitoring all available symptoms.
Painless form of myocardial infarction
The low-symptomatic, asymptomatic or painless form is very difficult to diagnose. These variants of myocardial infarction with a Q-tooth can often be observed in patients with diabetes mellitus, in elderly people and the elderly, in persons who have recently undergone surgical intervention, as well as in patients with mental illness or cognitive disorders.
In some situations, the development of the painless form may be due to a relatively small degree of myocardial damage (so-called small-focal infarction). Diagnostic detection of this variant of pathology is usually difficult, characteristic changes on the electrocardiogram may be absent, and the diagnosis is made only on the basis of information obtained during the troponin test.
In the absence of pain syndrome, the doctor should collect the most complete anamnestic picture, perform an examination to identify other objective signs of the pathological process in the myocardium. Attention should be paid to such symptoms:
- disorders of consciousness;
- lividity of the fingers, lips and nasolabial triangle;
- difficulty breathing;
- profuse sweating;
- fever, chills;
- low blood pressure, or low pulse blood pressure;
- ballooning of the venous vessels in the neck area;
- slowing or speeding up of the heartbeat;
- the onset of new heart murmurs;
- abnormal III, IV heart tone;
- low oxygen levels in the blood;
- swelling in one lower extremity;
- discrepancy in blood pressure readings on the left and right arm;
- pericardial or pleural friction murmurs;
- weakness or lack of breathing on one side of the lungs;
- the onset of pulmonary wheezing;
- focal neurological symptoms;
- pain when you feel your abdomen.
Even if at least one of the above manifestations is detected, the person should be hospitalized as an inpatient.
A common heart attack situation is as follows:
- pain is absent, but suddenly decreases blood pressure, dizziness is noted;
- his eyes go dark, cold sweat breaks out.
In such a situation, you should immediately call "emergency help", put the person on a bed with an elevated headboard, open the window and loosen clothes, exclude any physical activity, categorically exclude smoking, food and alcohol. Nitroglycerin can be placed under the tongue or injected with Isoket.
Unfortunately, it is far from always possible to detect a painless form of infarction. According to statistics, in a quarter of all cases of myocardial damage, infarction becomes an incidental finding during the autopsy of a deceased person. Some of these cases, most likely, occur in conditions when there is no possibility to perform a full and high-quality diagnosis, or the patient simply does not seek medical help, not realizing the seriousness and danger of his condition.
Arrhythmic form of myocardial infarction
Arrhythmia is a sign characteristic of any form of myocardial infarction. However, in some cases, this symptom comes to the forefront, completely displacing other manifestations, including pain. Among the many different rhythm disturbances in patients with acute infarction may occur:
- Arrhythmias due to lack of electrical stability of the damaged area of myocardium (ventricular extrasystole, ventricular tachycardia, accelerated rhythm - ventricular and AV junction).
- Arrhythmias associated with acute heart failure and high tone of the sympathetic nervous system, which, in turn, is explained directly by the acute infarction (atrial fibrillation, sinus tachycardia, paroxysmal atrial tachycardia, atrial extrasystole).
- Bradysystolic arrhythmias (sinus bradycardia, intraventricular and atrioventricular blockades, substitution rhythms from the atrioventricular junction).
In most cases, severe types of arrhythmias occur in the acute and acute period of infarction. Often the problem appears even before the moment of hospitalization of the patient, so it is important that at the stage of pre-hospital care, the medical specialist has everything necessary to provide adequate care to a person with an arrhythmic form of attack.
The state of central hemodynamics plays a major role in the dominance of rhythm and conduction disorders. Failure of the systolo-diastolic left ventricular mechanism is characterized by a decrease in cardiac output, the development of sinus tachycardia, which maintains the minute volume of blood flow. At the same time, cardiac hemodynamic load increases, which explains the appearance of arrhythmia.
Arrhythmic form of myocardial infarction is a die-off of a zone of muscle tissue of the heart (most often caused by detachment of atherosclerotic plaque or thrombus from the wall of a coronary vessel with subsequent occlusion of its lumen), which is manifested mainly by heart rhythm disturbance. Atrial fibrillation is most often found in patients with infarction. Additional symptoms:
- the sensation of your own heartbeat;
- shortness of breath;
- feelings of anxiety and fear.
If not treated at any stage of an attack, cardiac arrest can occur, so it is important to get the patient qualified medical attention as soon as possible.
Cerebral form of myocardial infarction
Cerebral or cerebrovascular form of the pathology is diagnosed mainly in elderly people with stenoses of intracranial and/or extracranial arterial vessels. Many of them have previously experienced episodes of circulatory disorders in the brain.
The cerebral form is more often manifested by disturbances of consciousness, fainting, dizziness, attacks of nausea (possibly with vomiting). Some patients have symptoms of transient cerebral circulation disorder, up to severe manifestations and background development of stroke.
The main symptoms of cerebral myocardial infarction:
- pain in the head (sudden, dull);
- dizziness;
- disorders of consciousness (stunned, pre-syncope, up to fainting);
- tinnitus;
- Increased fatigue and general severe weakness;
- numbness of the limbs, face, head, other parts of the body;
- seizures;
- painful sensations in the neck, chest, ribs, back;
- trembling fingers, paresis;
- impaired speech (pronunciation difficulties, incomprehensibility of speech - as if "tongue-tied");
- hypertrophied feelings of anxiety, sometimes tearfulness, certainty of a bad outcome;
- sudden apathy, indifference.
Often cerebrovascular manifestations are combined with heart pain, digestive disorders (abdominal pain, nausea, "nervous" diarrhea), heaviness of breathing, loss of voice.
The situation requires immediate hospitalization of the patient in a cardiology or neurology department, where he will undergo quality diagnosis and emergency medical care.
Ischemic processes in the brain occur due to a decrease in minute cardiac volume provoked by left ventricular damage or rhythm and conduction disorders. In some cases, we are talking about Morgagni-Adams-Stokes attacks, which are accompanied by loss of consciousness, respiratory dysfunction, convulsions. The appearance of this syndrome is explained by acute oxygen deficiency of the brain, which is associated with a sharp decrease in cardiac output.
In some patients, cerebral ischemia occurs as a result of cerebral thromboembolism due to the formation of blood clots in the left ventricle (during the development of extensive myocardial infarction). In this situation, it is more often said not about the cerebral form of myocardial infarction, but about its complicated course.
Hemorrhagic strokes occurring against the background of myocardial infarction occupy a special place. Such events occur in about 1% of patients and are a consequence of intensive and insufficiently controlled antithrombotic treatment.
Collaptoid form of myocardial infarction
The collaptoid variant is manifested by the abrupt development of collapse - the most dangerous condition in which there is a sudden arterial hypotension, dizziness, cold sweat, darkening of the eyes. The clinical picture is completely similar to the phenomena of cardiogenic shock.
Such development of events is found in 6% of patients and ends unfavorably in almost half of cases. Patients have an acute disruption of vascular perfusion, rapid disorder of peripheral and microorgan hemodynamics. There is a failure of blood circulation, metabolism and water-electrolyte balance is disturbed, tissue hypoxia increases, multi-organ failure develops.
The collaptoid form is typical of patients with extensive cardiac muscle damage, patients with arterial hypertension and diabetes mellitus, individuals with prior heart failure, left bundle branch block and impaired left ventricular ejection fraction.
The pathophysiologic mechanism of collaptoid form of myocardial infarction is quite complex, different organs and systems with different degrees of adaptation are involved in the process. Myocardial tissue damage and necrosis provokes systolic dysfunction, vascular contractility decreases, arterial pressure drops, peripheral perfusion deficit occurs. Increasing hypotension contributes to the aggravation of ischemic processes, which is accompanied by pronounced changes in the electrocardiogram and ultrasound monitoring.
Ischemia provokes fluid and sodium retention in an attempt to maintain perfusion by increasing intravascular volume. This compensatory response leads to increasing pulmonary edema, impaired cardiac function and hypoxia.
Extremely severe critical condition without timely emergency medical care ends in the death of the patient.
It is important to realize that in many cases, an intense attack of heart pain is not the main sign of myocardial infarction. There are many forms of atypical clinical course of the pathological process. Therefore, when making a diagnosis, you can not be guided solely by symptomatology. Additional significance has such signs:
- acute ischemic changes on the electrocardiogram;
- occurrence of abnormal Q teeth on the electrocardiogram;
- visualization of myocardial zones with loss of viability or impaired local contractility in the form of signs characteristic of ischemia;
- Detection of intracoronary thrombi during coronary angiography.
In addition, an important criterion for the detection of myocardial necrosis is an increase in the level of relevant markers in the blood. Cardiac troponin is preferred and should be determined as soon as possible.
The heart is an organ that is particularly sensitive to ischemic changes. Lack of adequate collateral circulation in case of occlusion of a major coronary vessel after half an hour leads to death of cardiac muscle cells. Such dynamics of myocardial necrosis and explains the need for the earliest possible measures for diagnosis and treatment of myocardial infarction. A preliminary diagnosis should be established already at the first contact of a medical specialist with the patient. In turn, the health care provider should be able to perform and interpret the electrocardiogram. If the specialist is unable to interpret, a remote consultation should be performed as a matter of urgency.
Regardless of the form of myocardial infarction, electrocardiography is mandatory: diagnosis based on clinical symptoms alone is not possible.
Literature
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