Description, signs, classification and treatment of unstable angina

Description of the disease

My patients at the first visit often ask the question: "What is unstable angina pectoris: a syndrome, a separate disease or a stage of exacerbation of chronic coronary artery disease?" The most accurate definition will be the following: this is an acute myocardial ischemia, which does not lead to necrosis, that is, death, of heart cells.

The sudden development of symptoms is similar to the clinic of a heart attack, therefore, in modern cardiology, unstable angina pectoris is included in the concept of acute coronary syndrome (ICD-10 code - I20.0). This diagnosis is "working", urgent and should be clarified in the next few hours after the patient is admitted to the hospital. The final word here belongs to laboratory tests: if the markers of myocardial necrosis are elevated, this is a heart attack, if not, unstable angina pectoris.

Etiology

At the heart of unstable angina, however, like any other form of ischemic heart disease, is atherosclerosis - the deposition of cholesterol in the vessel wall, leading to the formation of plaques. They can grow and penetrate inside it, which ultimately leads to narrowing of the arteries and, as a result, hypoxia (oxygen starvation of cells). The clinic is especially pronounced with an increase in heart rate, for example, when walking fast, climbing stairs.

A vulnerable atherosclerotic plaque leads to unstable angina pectoris: the membrane covering its lipid core becomes thinner under the influence of various factors. This triggers a chain of reactions - inflammation, thrombus formation. A characteristic clinical symptom is pain, which is accompanied by low exercise tolerance, shortness of breath.

Symptoms of unstable angina

Most patients come to me with a typical set of complaints and symptoms.

These include:

• pain behind the sternum or in the region of the heart (sometimes in the epigastrium, back, neck);
• discomfort occurs with minimal physical activity and even at rest;
• "Nitroglycerin" (symptomatic) does not help.

A vivid example from practice: if earlier the patient had pain when climbing four floors and was removed with nitrates (a sign of angina pectoris), with an unstable form, the symptom appears after one flight of stairs, requires two or three doses of "Nitroglycerin" and does not always go away completely.

As an examination, I advise my patients to perform an electrocardiogram, ultrasound of the heart, take blood for markers of myocardial necrosis.

On the ECG, changes will be visible during an attack: depression of the ST segment, negative T wave, arrhythmia is also possible. In the interictal period, the film may be normal.

On ultrasound, we are looking for areas of impaired myocardial contractility, which indicate ischemia.

Classification

In clinical practice, I (like most cardiologists) use the Braunwald classification of unstable angina (C. Hamm, E. Braunwald).

It helps:

• assess the severity of the patient's condition;
• identify the risk of developing myocardial infarction and sudden death;
  • determine which department (intensive care unit, cardiology) to hospitalize the patient and how to carry out his treatment.

The classification uses 2 parameters: the time of onset of pain and the condition.

By date:

• Class I - includes new-onset and progressive angina pectoris. Pain syndrome in such a patient developed for the first time in his life, or the characteristics of previously existing attacks changed. Symptoms appeared 1-2 months before the time of treatment.
• Class II - anginal attacks occurred 4 weeks ago, but over the past 2 days, the state of health has not deteriorated.
• III class - This is an acute chest pain that the patient notes in the last 1-2 days, but not earlier.

Depending on the conditions, 3 classes are also distinguished:

• A - secondary unstable angina pectoris. This form occurs under the influence of external factors that are not directly related to the heart: anemia, thyrotoxicosis, fever, hypertension, infections, etc. For example, a week ago one of my patients developed pain syndrome without visible damage to the coronary vessels, but in general on a blood test, I determined that he had a decrease in the number of erythrocytes and hemoglobin levels. There was an episode of gastrointestinal bleeding a week before the detection of unstable angina.
• V - primary unstable angina pectoris. The reason for this form is the thinning of the lining of the atherosclerotic plaque, its vulnerability; doctors call this option "true angina" (there is no action of external (non-cardiac) factors).
• WITH - postinfarction angina pectoris. The most unfavorable variant of the disease develops in the first 2 weeks after a heart attack. These patients have a very high risk of sudden death.

The risk of sudden death and other fatal complications with the class of angina pectoris increases: from minimal with IA (an outpatient treatment option is possible) to maximum with IIIC (intensive care unit).

Since unstable angina is considered one of the variants of acute coronary syndrome without ST elevation, I recommend using the GRACE scale (Global Registry of Acute Coronary Events) to assess the prognosis and risk of cardiovascular death. It is the gradation of the severity of the condition in points that should play a decisive role in the choice of treatment tactics (interventional intervention or drug option), and not the clinical picture of the disease: a high score is the rationale for emergency coronary angiography.

First emerging form

Among the classes of unstable angina pectoris, I consider it important to single out the first one that has arisen. Already from the name it becomes clear that it develops in a person who was previously unfamiliar with this problem.

In my practice, there have been cases when patients regarded pain as a manifestation of problems with the spine, were treated by an osteopath, or blamed everything on heartburn. Unfortunately, myocardial infarction became a frequent result of such "ordeals". But this could have been avoided. How?

What is the algorithm for providing assistance before the arrival of the medical team?

Lay the patient down, provide rest, access to air, give a tablet of acetylsalicylic acid to chew, if any, dissolve "Nitroglycerin" by placing it under the tongue.

What should the ambulance do upon arrival at the call (prehospital stage)?

• Anesthetize the patient with narcotic analgesics.
• Introduce an anticoagulant ("Heparin").
• Give a loading dose of the second antiplatelet agent (Clopidogrel, Ticagrelor, Prasugrel).
• Start infusion of "Nitroglycerin" taking into account the level of blood pressure.
• Give beta blockers intravenously.
• If necessary (low blood gas concentration) start oxygen inhalation.

What is the difference between unstable and stable

Stable and unstable angina pectoris can alternate in the same patient. Differential diagnosis (difference) between them lies in the nature and duration of pain, the provoking factor and reaction to "Nitroglycerin".

In patients with stable angina pectoris angina ("angina" is the Latin name of the disease) attacks occur when performing the same physical work and stop after taking "Nitroglycerin" or cessation of the load. Patients get used to this: they know what actions can trigger an attack, and they take the medicine beforehand.

With unstable angina, episodes of pain:

• occur more often;
• last longer;
• provoked by minimal exertion or developed during rest;
• do not always stop after taking Nitroglycerin.

These symptoms should cause anxiety in the patient, as they indicate the instability of the plaque and the threat of a heart attack.

Treatment

Treatment of unstable angina pectoris involves 2 tasks:

• improve the patient's prognosis and reduce the risk of cardiovascular complications;
• remove the symptoms of the disease.

I am actively fighting against the "reappointment" of drugs, so in my practice I use only those that prolong the patient's life and improve its quality.

To improve the prognosis, drugs are used that have proven efficacy and safety in large clinical trials.

These include:

• antiplatelet agents;
• statins;
• beta blockers;
• ACE inhibitors.

Antiplatelet agents are a mandatory group of drugs and are used to prevent blockage of blood vessels. The standard of care for unstable angina is dual antiplatelet therapy (DAPT) up to 12 months after the condition develops. The duration of admission depends on whether there was an intervention on the coronary arteries. The following drugs for DATT are available on the Russian pharmaceutical market: acetylsalicylic acid, Clopidogrel, Ticagrelor, Prasugrel. When prescribing a combination, one of the components will necessarily be "Aspirin", and the choice of the second depends on the clinical situation.

Prophylactic administration of proton pump inhibitors (Pantoprazole, Esomeprazole) to protect the stomach in patients receiving two antiplatelet agents is not indicated. The exception is when a person has had an episode of bleeding or peptic ulcer disease.

Are statins needed?

Statins are the most talked about class of drugs on the Internet. Many argue that they are harmful, but there is no evidence of this fact. Indeed, there are situations where the prescription of cholesterol-lowering agents is not justified. But, if a doctor is dealing with coronary heart disease (in particular, with unstable angina pectoris), he is obliged to prescribe a statin, since the drug is included in national treatment recommendations and international protocols.

The effect of the drug is not only to lower blood cholesterol levels, but also to stabilize the plaque. In addition, statins have anti-inflammatory effects. This is very important given the fact that endothelial dysfunction and systemic inflammation underlie atherosclerosis. It has been proven that long-term administration of high doses of the drug can lead to plaque regression. Recommended for use are: "Simvastatin", "Atorvastatin", "Rosuvastatin", "Pitavastatin".

Beta-blockers have an anti-ischemic effect, decrease heart rate, lengthen diastole. Their early prescription for unstable angina pectoris significantly improves the prognosis of life in patients. I often use "Metoprolol succinate", "Bisoprolol", "Carvedilol" in practice.

ACE inhibitors are prescribed for patients with arterial hypertension, chronic heart failure, or in case of myocardial infarction. The positive result of their action is to prevent left ventricular hypertrophy. With ischemic heart disease, "Perindopril" and "Ramipril" have proven their effectiveness.

If we talk about drugs to reduce symptoms, then in the case of unstable angina, nitrates will be the means of choice. In the hospital, they are administered intravenously, the dose is taken by the patient slowly, with a reference to the level of blood pressure.

In addition to drug treatment methods, intracoronary interventions - stenting - are widely used. Having revealed hemodynamically significant stenosis (narrowing of the artery by more than 70%) with coronary angiography, it is possible to perform stent placement in one procedure. A metal structure is placed in the modified section, which is a hollow tube of a cellular structure. Such percutaneous intervention protects against severe cardiovascular catastrophe - heart attack.

Forecast: is there a chance to recover

The answer to this question sounds disappointing: absolute recovery cannot be achieved. But don't be in a rush to panic. In the 21st century, almost all diseases have a chronic course: hypertension, diabetes mellitus, obstructive pulmonary disease, and so on. The causes of these pathologies are not bacteria, with which doctors have successfully learned to fight, but the way of life and the ecological situation.

At the heart of coronary heart disease is atherosclerosis, which begins to develop with the birth of a person. Unstable angina is an acute manifestation of this process. By removing the symptomatology by stenting, we do not eliminate the root cause. To prevent new exacerbations, it is necessary to constantly take medications that prevent pathologies from progressing.

All patients want to keep their pharmaceuticals to a minimum, and some will stop treatment after they feel better. Discharge from the hospital in their understanding means freedom from drugs, because there is no more pain. Alas, such a decision often turns against them with dire consequences - a hospital bed and life-threatening complications.

In conclusion, I would like to add that cardiovascular diseases cannot always be defeated, but it is quite possible to prevent them. Weight control, smoking cessation, regular physical activity, and normal cholesterol and glucose levels will help you fight for your health.

Patient education is an important part of my work. Everyone does their own thing, and mine is to help people get rid of heart problems.Since this can be done only at the early stages of the development of pathology or at the stage of the formation of a predisposition to it, I pay a lot of attention to issues of nutrition, lifestyle and screening. Only in this way - together - can we significantly improve the health of the nation.