Acute coronary insufficiency

Disease classification

Acute coronary insufficiency is a state of inadequacy of myocardial oxygen demand and its actual supply to the heart muscle. The heart receives an insufficient amount of blood, ischemia occurs. A person feels pain, shortness of breath, a burning sensation behind the breastbone.

An attack (paroxysm) of heart failure is provoked by psychoemotional stress and physical activity of the patient, but it can also occur at rest. In accordance with this, two types of exacerbation of the coronary syndrome are distinguished:

• Exertional angina.
• Rest angina.

With physical exertion, the consumption of blood by the heart muscle increases. In case of psychological stress, the adrenal glands secrete hormones adrenaline and cortisol, which narrow the lumen of the coronary arteries that feed the myocardium.

The cause of angina pectoris is myocardial ischemia due to pathological narrowing of the coronary arteries.

Stenosis of the coronary arteries occurs due to the development of an atherosclerotic process in them. With atherosclerosis of coronary arteries, low-density cholesterol is deposited on their inner wall, forming fatty strips. Further, the oxidation of the lipid layer occurs, which leads to the appearance of properties alien to the body. The immune system attacks the altered cholesterol, which is absorbed by macrophages, which then become foam cells. They are located under the inner lining of the artery - the intima, which becomes the lining of the plaque that lies between the intima and the media - the middle membrane.

A seal is formed that blocks the lumen. In the future, due to the rapid flow of blood, it can be damaged - the process of intravascular blood coagulation starts, creating a blood clot.

The damaged endothelium is covered with fibrin and collagen threads, overgrown with connective tissue. Fibrous changes cause thickening and thickening of the walls of the coronary arteries, narrowing of their lumen. Vessels become inelastic. A torn off plaque can clog the vessel.

In addition to the atherosclerotic process, some infectious, autoimmune and allergic diseases contribute to the narrowing of the lumen of the coronary arteries. With infections (especially chlamydia, systemic vasculitis), parietal blood clots appear in the coronary vessels as a result of intravascular blood coagulation. It is possible to partially block the coronary arteries by a thrombus, or to organize a blood clot with the formation of connective tissue in its place.

Stenosis also develops when:

• Accumulation of amyloid on the wall of coronary arteries in amyloidosis.
• Aortic stenosis.
• Myocardial hypertrophy.

With an increase in the load on the cardiovascular system (as a result of stress or physical exertion), the need for oxygen increases. Narrowed coronary arteries provide inadequate blood supply to the myocardium. The release of adrenaline in response to cold or stress causes spasm of the coronary vessels, which leads to the development of the disease.

There are such forms of pathology:

• Stable angina.
• Unstable angina.
• Myocardial infarction.

Stable angina is an acute insufficiency of the coronary circulation, which is stopped by the intake of nitrates or the cessation of physical activity, which caused the pain syndrome.

Unstable angina pectoris is a more severe violation of myocardial circulation, a pre-infarction state. The attack is not stopped by stopping physical activity and threatens the development of a heart attack with the death of areas of the heart muscle, which the narrowed artery should provide with blood.

There are several types of unstable angina:

• For the first time, the period is 28-30 days from the onset of symptoms.
• Progressive - increasing the dose of nitroglycerin, which relieves chest pain.
• Spontaneous - the appearance at rest of seizures that are not eliminated by nitrates. The duration of the attack is over 15 minutes. The attacks are repeated.
• Variant, Prinzmetalla - during an attack on the ECG, elevation (elevation) of the ST segment is observed, indicating serious ischemia and myocardial damage, similar to a heart attack.
• Postinfarction - the appearance of attacks 24 hours after the appearance of a necrosis focus in the heart, but not later than 8 weeks.
• A heart attack is a condition when a prolonged (more than 20 minutes) ischemic attack leads to the death of muscle tissue. This is accompanied by impaired excitability, contractility, and conduction of the heart. The condition is irreversible and can lead to heart failure and cardiogenic shock if the lesion is extensive.

Sudden death syndrome

Sudden death from coronary artery disease occurs within 24 hours of chest pain and other symptoms. Sometimes, this is the only manifestation of acute coronary insufficiency.

In 1964, the World Health Organization proposed to call this definition death that developed 6 hours after the onset of the first attacks.

At the moment, sudden death is the death of a patient within 24 hours after an ischemic attack, not complicated by cardiogenic shock, heart rupture or cardiac asthma.

The reason for this outcome may be a complete cardiac arrest, which has arisen due to damage to the conducting system, which provides rhythmic contraction. It is also extensive necrosis of cardiomyocytes, making it impossible for an adequate blood supply to the brain. Due to prolonged hypoxia due to heart failure, the brain dies and biological death occurs.

This syndrome often occurs in elderly and middle-aged patients with cold spasm, severe stress. In young athletes, it is caused by vasospastic angina pectoris, triggered by stress combined with high physical exertion. This category of persons uses antihypoxic drugs that reduce myocardial oxygen demand and increase resistance to hypoxia. However, Prinzmetall's angina pectoris, even in this case, can cause death.

The factors that increase the risk of sudden death are:

• Metabolic syndrome (glucose tolerance, overweight, hypertension).
• Eating an excess of fat and salt.
• The presence of a large atherosclerotic plaque in combination with high blood pressure.
• Smoking, alcohol abuse.
• Systemic vasculitis (lupus) and other conditions characterized by increased blood clotting and intravascular coagulation.

How to define coronary insufficiency?

The disease manifests itself in the form of retrosternal burning pains that can radiate to the left scapula and shoulder, lower jaw and neck. Sometimes there are back pains that mimic the symptoms of osteochondrosis.

A painless form of the disease is also possible, especially in those who suffer from diabetes mellitus.

Ischemic attack is accompanied by anxiety and fear of death, and sometimes nausea and vomiting. Pain attacks are triggered by low air or water temperature (when diving into an ice hole), physical activity and stress.

It is also possible to develop pulmonary edema due to heart failure (cardiac asthma). In this case, the patient exudes pink foam from the mouth.

For diagnostics, ECG, EchoEG, coronary angiography are used. Blood sampling is carried out for biochemical analysis for troponin, lactate dehydrogenase, in case of a heart attack - for creatine phosphokinase.

First aid for exacerbation

Emergency care consists in an urgent appeal to a medical institution for hospitalization of a patient. To try to stop the attack of pressure in the chest, it is necessary to lay the patient down and unfasten the buttons on the clothes that make it difficult to breathe, and loosen the tie. In this case, a person should be in a well-ventilated, but warm room.

Nitroglycerin and other nitrates are used to relieve stenosis of the coronary lumen. When combined with arterial hypertension, it is advisable to use beta-blockers to reduce the oxygen demand of myocardial tissue.

If the attack persists for more than 20 minutes, the patient is given aspirin to chew to eliminate the thrombosis.

In a hospital for thrombosis of coronary vessels, anticoagulants are used ("Clexan", "Heparin"), as well as fibrinolytic enzymes that dissolve clots - "Alteplaza", "Urokinase". These drugs restore vascular patency.

As drugs to increase resistance to ischemia, "Trimetazidin", "Riboxin", "Preductal" ("Midronat") are prescribed. In severe cases, coronary artery bypass grafting is indicated.

Therefore, acute coronary insufficiency is a dangerous and painful condition in which timely diagnosis and treatment is important. Most patients avoid early death only thanks to timely first aid.