Ischemic heart disease causes irreversible effects in the cardiac muscle. Continued disruption of cardiac cell metabolism leads to circulatory failure and may be complicated by myocardial infarction.
This is a complication that is characterized by the death of cardiomyocytes and is the most common cause of cardiac arrest.
- 2 acute acute clinical picture
- 3.1 Electrocardiography
- 3.2 Echocardiography
- 4 Laboratory methods
- 5 Additional studies
Clinical presentation of the acute form
Symptoms that characterize myocardial infarction differ and depend on the form of the disease. Hypertensive crisis, excessive fatigue, severe physical stress or stress factors that contribute to the manifestation of the disease.
- Pre-infarction state of .It occurs only in half of cases of myocardial infarction. It manifests itself in unstable angina, which has a progressive course.
Acute condition of .The main symptom is a pain syndrome of varying severity. Its intensity depends on the area affected by the myocardium.
The pain is of a different nature:
- is searing;
The peculiarity of pain in myocardial infarction is that they radiate to the neck, collarbone, left shoulder, ear, lower jaw, teeth or under the scapula. Pain lasts from half an hour to several days and does not cease after taking nitrates.
- Acute condition of .There are signs of heart failure and hypotension. Pain passes, except when pericarditis is attached. Necrosis, inflammation and myomalation cause fever. The larger the area of necrosis. The higher and the longer the temperature rises.
- The sub-state of the .The patient feels better. No pain, body temperature is normal. Systolic murmur and tachycardia pass. Heart failure is not expressed.
- Post-infarction status of .Deviations in laboratory and physical parameters are not determined. Clinical symptoms are absent.
Atypical forms of myocardial infarction .In elderly patients with signs of atherosclerosis, atypical forms of infarction may occur. This clinical picture is often observed against a background of repeated myocardial infarction.
Atypicality is associated with unusual localization of pain or its absence:
- Symptoms of pancreatitis - pain in the upper abdomen and right upper quadrant, nausea, vomiting, hiccups, flatulence.
- Symptoms of an asthma attack - increasing dyspnea.
- Irradiation of chest pains in the shoulder, lower jaw, arm, ileal fossa.
- Pain-free ischemia in case of impaired sensitivity, for example, in diabetes mellitus.
- Neurological symptoms - dizziness, impaired consciousness.
- Symptoms of intercostal neuralgia in patients with osteochondrosis.
Pre-hospital diagnostic activities
A preclinical diagnosis is the questioning of a patient and the identification of symptoms. Features of the development of a heart attack include:
- atypically prolonged pain syndrome;
- no effect on nitrate intake;
- no dependence of pain on body position;
- high intensity of symptoms, in comparison with attacks that occurred earlier and did not end with a heart attack.
The basic diagnosis is instrumental research methods such as EGC and EchoCG.
ECG - is the most common method of detecting myocardial infarction, even in the case of its asymptomatic .The acute stage and the process of recovery are characterized by a negative T wave. With a large focal infarction, a pathological QRS complex or a Q wave is found. Healed myocardial infarction manifests itself in a decrease in the amplitude of the R wave and the preservation of the Q wave.
The photo-pictures below show variants of what the ECG changes look likemyocardial infarction with interpretation and description, signs by stages( from acute to postinfarction) and localization.
Click the picture above to see it in full.
Echocardiography reveals thinning of the ventricular wall and a decrease in its contractility. The accuracy of the study depends on the quality of the image.
There are changes in the biochemical blood counts of , so this analysis is performed in the diagnosis of myocardial infarction.
- The number of neutrophils increases in the first two days, reaching a peak on the third day. Then it returns to normal values.
- is growing.
- Increases the activity of hepatic enzymes-transferases AcAt and AlAt.
Such changes are explained by inflammation in myocardial tissue and scar formation. Also, changes in the level of enzymes and proteins are found in the blood, which is significant for the diagnosis.
- Increase in the amount of of myoglobin - within 4-6 hours after the onset of pain syndrome.
- Creatine phosphokinase ( CKF) increases by 50% in 8-10 hours after the onset of the disease. Two days later he returns to normal.
- Lactate dehydrogenase ( LDH) - the enzyme activity rises on the second day of the disease. Values return to normal after 1 to 2 weeks.
- Troponin is a contractile protein, the amount of which increases with unstable angina. Its isoforms are highly specific for myocardial infarction.
In some cases, the above studies may not be sufficient. For the final diagnosis or clarification of the nuances of the course of the disease, the following procedures may be required:
- Chest X-ray .Myocardial infarction can be accompanied by stagnation in the lungs. This is noticeable on the radiographic image. Confirmation of the complication requires adjustment of the treatment regimen.
- Coronarography .Angiography of the coronary artery helps to detect its thrombotic occlusion. Determines the degree of decrease in ventricular contractility. This study is conducted before surgery - angioplasty or aortocoronary bypass, which contribute to the restoration of blood flow.
To prevent a heart attack, should be treated with existing angina and ischemic heart disease , avoiding stress, excessive stress, physical and emotional fatigue.