If you are suddenly worried about severe chest pain, you should seek the help of a doctor. With a certain set of symptoms, the patient is hospitalized, suggesting a heart attack, and already in the hospital, having specific equipment, the diagnosis is clarified. In the cardiology department, they will do tests for markers of myocardial infarction, as well as take ECG indicators and analyze patient complaints. Take into account that in the acute stage, an electrocardiogram may not give information about the coronary syndrome.
Note!
An informative ECG is more often found in elderly patients or in women. In most cases, such patients feel rather mild pain, and in some it is completely absent, which greatly complicates the diagnosis of the condition. Perhaps a deviation from the standard course and in the presence of impaired functionality of the endocrine system.
Doubting the exact diagnosis, needing additional information, the doctor will definitely take blood for the detection of markers of acute myocardial infarction. This method of clarifying the condition allows you to prevent medical error even in the case when the clinical picture is very blurry.
Markers: what are they?
Diseases of the heart and blood vessels are directly related to a violation of the quality of blood flow. Doctors found that the probability of a fatal outcome in case of malfunctions is higher if the patient suffers from vascular blockage, heart failure or a disturbance in the rhythm of contraction of the heart muscle. It was also established that the best prognoses for those patients who turned to the hospital on time for a heart attack and the doctors were able to immediately make the correct diagnosis. Quickly making an accurate diagnosis and taking steps to heal the patient helps minimize the likelihood of complications. When clarifying the diagnosis, blood must be checked, revealing the presence of biological markers in it.
Markers of myocardial infarction in the blood are protein structures, from the concentration and condition of which it can be concluded how difficult the patient's condition is. The state of the markers changes over time, which also helps to identify how long the heart attack began. In the analysis, you can determine whether angina pectoris occurs, whether necrotic processes have begun. Therefore, the diagnosis will be made accurately, which means that the treatment program is correctly selected.
The nuances of the question
Cardiac markers of myocardial infarction are highly specific, sensitive to necrotic processes in the heart muscle. A sufficient number of markers in the circulatory system for diagnosis is observed, and pronounced symptoms of a pathological condition hardly appear. A level sufficient to clarify the diagnosis remains for a long time.
Nowadays, doctors do not have information about the existence of a universal marker of myocardial infarction, an indicator that would give accurate information about the patient’s condition at the very beginning of the development of myocardial infarction, and as it progresses. The early markers, as you know, are observed only in the first few hours after the development of a heart attack, while the later ones manifest themselves after 9 hours and beyond. To clarify the diagnosis, it is necessary to analyze both groups of indicators.
Biochemistry and indicators
Markers of myocardial infarction in time is the first parameter to check the blood of a patient who enters the cardiology department. In particular, myoglobin, a pigment localized in soft tissues, points to an early process. Normally, the weight of the substance is about 18 kDa. In the first two hours of a heart attack, the concentration of this compound increases sharply, and after a day it is completely excreted through urine. Modern technologies are such that the determination of the concentration of the specified pigment is possible in just 10 minutes.
It should be borne in mind that myoglobin is concentrated primarily in skeletal muscle, and the concentration of this compound is determined by the effectiveness of the functioning of the kidneys. Myoglobin gives a certain idea of necrotic processes in the heart muscle, but the data are not complete and accurate, so in practice it is rarely used as the main early marker of myocardial infarction.
What else do you have?
A marker of myocardial infarction is creatine phosphokinase (CPK). This substance is normally found in the muscles, therefore it is rarely used to determine a heart attack and only as an additional signal - the CPK parameter alone cannot give an accurate idea of the ongoing processes. Normally, CPK is observed in blood plasma 4 hours after the onset of an acute pathological condition.
You can suspect a heart attack at an early stage if the tests show a cardiac protein. Checking for this parameter is mandatory if you suspect a heart attack. In the presence of cardiac protein, one can confidently talk about necrotic processes in the body. Doctors specified that the protein structure is necessary for the connection of carboxylic acids. In the heart muscle, this protein is contained in a sufficiently high concentration if a heart attack begins, but in a healthy state its content is much lower. The specificity of cardiac protein as a marker of myocardial damage is higher than the previously mentioned compounds.
Status Progress
Later markers of myocardial damage are biochemical indicators that allow us to clarify necrotic processes. Usually they can be detected six hours after the onset of the pathological condition, some later. One of the classic markers is lactate dehydrogenase (LDH). This is a cytosal protein structure, which is currently one of the main indicators that help the doctor detect cell damage characteristic of a heart attack. At an early stage, analysis on LDH does not make sense, since the concentration in the circulatory system sufficient for diagnosis is observed quite late. The presence of LDH helps to distinguish between heart attack and angina pectoris.
Another important biochemical marker of myocardial infarction is aspartate aminotransferase. Quite high rates of concentration of the compound are characteristic of skeletal tissues, heart muscle, liver, and kidneys. Necrotic susceptibility of the substance is relatively low, therefore, it is not used as the main indicator for the detection of a heart attack.
Nuances of analysis
Cardiac protein structures involved in contractile processes, and especially troponins, should be noted as standard laboratory markers of myocardial infarction. Due to the high specificity, the determination of these structures in the analysis helps to quickly diagnose a heart attack, and therefore, provide the patient with qualified help earlier. Based on the indicators of the content of these structures, the doctor can predict the development of the condition, assess the patient's chances of survival and cure.
When determining a clinical myocardial infarction, it must be remembered that the activity of enzymes is not always explained by just such a condition, but may indicate other disorders in the functioning of the heart, as well as non-cardiac diseases. Only a comprehensive examination allows you to establish a diagnosis accurately and differentiate it from conditions explained by medical interventions (some examination methods and injectable drugs). A sudden increase in the number of enzymes is possible with thrombolytic therapy, since biologically active structures are washed out of cardiac tissues. In order for the analyzes to be as accurate and detailed as possible, the activity of different substances should be determined for some time. Several research methods are known - in each clinic, doctors decide on their own in favor of turning to a particular work option.
Indicators and change over time
The earliest marker of myocardial infarction, myoglobin, grows in the first couple of hours after an attack, and reaches its highest levels after 6 hours. After a day, the parameter returns to normal.
CPK rises after 4 hours, the highest rates are observed after 16 hours. After two days, the values return to normal.
AcAb is a marker of myocardial infarction, increasing after (on average) 10 hours, and reaching a maximum by the second day. By the seventh day, the indicators return to normal.
LDH reacts later than others. The enzyme is activated approximately 24 hours after the initial attack, and the highest rates are detected on average 4 days after it. Closer to the 14th day, the LDH content decreases to a stably normal value.
Mandatory analysis for KFK-MV-isoenzyme, I and T troponins. The rapid detection of heart attack is often practiced through immunological studies to determine the parameters of troponin-T. This protein structure is observed in the muscle fibers responsible for the contraction, in the fluid inside the cells. In analyzes, the maximum values can usually be observed already three hours after the attack, and on the third day there is a second peak value. After 1.5-2 weeks, the value stabilizes and drops to normal.
It's important to know!
The method for studying the patient's condition described above allows determining markers of myocardial infarction, indicating not only large, but also small lesions. This is especially important, given that doctors are regularly forced to work with people with angina pectoris in an unstable form - analysis of markers helps to make an accurate diagnosis and formulate a prognosis. It is known, for example, that at normal troponin-T concentrations, up to 95% survive, and during a period of stationary observation of an acute heart attack does not occur.
To make an analysis, 150 μl of blood is needed. The liquid is applied to the strip intended for this and after 20 minutes the results are checked. With a heart attack, the protein is detected in an amount of 0.2 ng / ml and above, that is, the strip will have two lines. With one line, the result is considered negative. To eliminate the erroneous result, the study is repeated after a few hours. It is allowed to do such testing before placing a person in a hospital of a cardiology clinic.
Relevance of the issue
In heart disease, the predominant percentage of deaths occurs in acute coronary syndrome and heart failure, as well as the presence of blood clots that block blood vessels and destabilize the rhythm of heart contraction. Clinical myocardial infarction with a minimal degree of probability leads to such complications if it is established early, for sure. The best prognosis for a patient who came to the clinic and received qualified help. The approach to stabilization should be chosen individually.
To formulate the most relevant recommendations for myocardial infarction, blood is taken for analysis, during which the biochemical markers discussed above are determined. Based on the indicators of concentration, we can understand what are the features of the pathology in a particular case. Even if the condition is relatively mild, a heart attack requires urgent treatment, and in the future, prevention of a repeat situation.
Markers: so different, but all important
It is possible to formulate adequate recommendations for myocardial infarction, assessing the state of the markers, since they are characterized by a fairly high sensitivity to necrotic processes. If symptoms increase rapidly, markers are also soon observed in the circulatory system in quantities where an accurate diagnosis is possible. Such parameters remain for a sufficiently long period, so doctors have enough time to determine the diagnosis.
A serious problem of medicine is the lack of information about some universal marker that would give an idea of the pathological condition both at an early stage and at a later date. Late indicators are considered more accurate.
Problem: where and why?
A heart attack and necrotic processes often begin due to a blood clot blocking the bloodstream. A blood clot appears due to an atherosclerotic plaque. The heart muscle does not receive the necessary nutritional components, primarily oxygen, which significantly reduces viability: on average, it is estimated at 30 minutes. If you have time to help the patient during this period, the muscle can be saved. You can only help in the conditions of resuscitation, in intensive care of the cardiology department of the clinic. In the absence of such support, tissue degeneration, necrotic processes progress, it is impossible to reverse them. Five hours after a heart attack, the affected area completely dies.
Clarification of the diagnosis of a heart attack in many cases is complicated by mixed symptoms and the absence of typical manifestations. The classic picture suggests pain in the left half of the chest, manifestations of failures on the cardiogram and the presence of biochemical markers. Clarification of the diagnosis is possible with a violation of the frequency and rhythm of the heartbeat, breathing difficulties and cold sweat. In patients, the skin turns pale, pain is given to the neck, ovens and hands, cramps are felt in the abdomen, shortness of breath is disturbing. In the absence of accurate conclusions in the initial diagnosis, a biochemical blood test is necessary. In the course of such a study, it is precisely established how difficult the process is, how large the area of damage.
How it works?
One of the indicators of a heart attack is resorption-necrotic syndrome. It is explained by the entry into the circulatory system of substances produced during aseptic necrosis. The presence of specific enzymes provokes a fever, is reflected in blood tests by a shift in the concentration of different components. Enzymes leave myocytes, whose vital activity has come to an end. In the presence of such phenomena, to confirm a heart attack, it is necessary to take an analysis for cardio-specific enzymes. If their level grows, while correlating with the dates identified by scientists, we can confidently talk about a heart attack.
Correct and quick clarification of the situation helps to differentiate heart attack sufferers from other people who have heart pain. Markers, as you know at the current level of development of medicine, are the most reliable way to identify a diagnosis. The information thus obtained is more accurate than a cardiogram.
Heart attack: what is it about?
A heart attack is an acute pathological condition due to blockage of blood flow in the coronary vessel. After some time, necrotic processes begin (for the heart muscle - about 30 minutes). Areas of necrosis are called ischemia. The cells located here cannot conduct impulses, contract and function in any other way, that is, the element becomes inert, which leads to disruption of the entire organ. The larger the focus, the more important cells for vital activity were affected, the stronger the heart attack will affect a person’s future.
With a heart attack, there is a risk of death in the first minutes of an acute condition, but some carry it without going to a doctor, and do not even suspect their illness. Specific features depend on the shape. There are two main classes: small foci and large. Large is also known for Q-infarction, since a specific tooth appears on the cardiogram, which is absent in a healthy person. It indicates a deep violation of the functionality of the heart structures. Sometimes this same condition is called transmural infarction, that is, a pathology in which necrosis spread along the wall in its entire thickness. Full recovery even after a long time is impossible: a scar appears. As a rule, pathology provokes severe consequences.
Small focal infarction (non-transmural) is diagnosed when necrotic processes do not penetrate the myocardial wall, and there is no characteristic tooth on the ECG. Some patients after such a heart attack fully recover, the heart works, as before the pathology. Others have consequences, but quite easy.
There are several options for localizing a site of necrosis: in the ventricle of the right or on the left, in the atrium. The latter is the least common, and the most typical variant is a lesion of the ventricle on the left. Perhaps a violation of the integrity of one of the sections of this area or several crystals. The most dangerous is a circular heart attack, that is, a condition that covers all the ventricular walls at the same time.