Angina pectoris is a symptom of acute myocardial ischemia, expressed by an attack of chest pain. In the vast majority of cases, angina pectoris is a manifestation of coronary heart disease and stands out as one of its clinical forms. A classification of angina pectoris, based on the features of its course, is used.
The first arising angina pectoris. Angina pectoris conditionally refers to this form within 6 weeks from the moment the first attack occurs. In this case, the first attack may be the only one or during this period the attacks are repeated and by the end of the 6th week angina pectoris can be assessed as stable or progressive.
Stable angina is characterized by the periodic occurrence of pain attacks under specific conditions, in particular at a certain level of physical activity, depending on which four functional classes of stable angina are distinguished: class I - attacks occur only during extreme physical exertion and quickly pass on their own after its termination; Grade II - seizures occur during the usual load for the patient (for example, when walking in a flat place at a distance of more than 500 m, with a calm climb up the stairs more than one floor) or are provoked by a pronounced emotional stress; the probability of attacks increases in the morning, in cold windy weather; pain is often stopped only by taking nitroglycerin; Grade III - attacks are provoked even by insignificant physical exertion, pain appears when walking calmly on level ground for a distance not exceeding 500 m, with a slow rise to one floor; Grade IV - seizures occur with minimal physical exertion (getting up from a chair, torso when putting on shoes, slow walking on level ground to a distance of 100 m), as well as at rest (especially at night), sometimes when the patient moves from a vertical to a horizontal position (which is associated with a short-term increase in heart function due to an increase in venous inflow).
Progressive angina pectoris. It is characterized by an increase, elongation and increase in the intensity of pain attacks (often with a significant decrease in the effectiveness of nitroglycerin), a relatively rapid transition of angina to a higher functional class. Progressive angina pectoris does not always, although often, end with the development of myocardial infarction.
Spontaneous, or special, angina pectoris (sometimes referred to as variant angina pectoris) is characterized by the appearance of anginal attacks without a visible connection with any external provoking factors; seizures are more severe and longer than with stable angina, more resistant to nitroglycerin.
The pathogenesis of angina pectoris in its initial stages coincides with the pathogenesis of acute coronary insufficiency, which is based on a mismatch between the ability to deliver blood to the myocardium through the stenosed or spasmodic coronary artery and its oxygen and nutrient requirements, which increase due to physical activity or severe psychoemotional stress. In the origin of nocturnal attacks of angina pectoris, coronary spasm plays a role; also suggest the role of enhancing vagal influences at night. Pathogenesis of a pain attack, i.e. actually angina pectoris, is associated with irritation of the ends of the sensitive fibers of the sympathetic nerves of the heart with substances released during ischemia from myocardial cells. Impulses go to the ganglia of the cervicothoracic region, penetrate the spinal cord, spreading to the zones of somatic innervation, reach the subcortical structures and the cerebral cortex, forming a sensation of pain with localization in the innervation zones from the upper thoracic segments. The disappearance of angina pectoris sometimes noted after myocardial infarction is explained by the destruction of nerve endings in the necrosis zone.
The clinical picture . With angina pectoris, a pain attack occurs during physical (sometimes emotional) stress and usually disappears 1-2 minutes after its cessation. The duration of a severe attack can reach 20-30 minutes, with a longer duration, focal dystrophic or necrotic myocardial lesions usually develop. In the vast majority of cases, the pain is localized deep behind the sternum, most often at the level of the upper third of the sternum body. Sometimes the zone of the most severe pain is shifted somewhat to the left or right of the midline. Patients define pain as constricting, pressing, sometimes as breaking, bursting, or burning. The intensity of the pain is different: from intolerable to barely expressed, comparable to a feeling of discomfort. Irradiation of pain is not always observed; in typical cases, pain radiates to the left shoulder, left arm, shoulder girdle (right-sided irradiation is less characteristic) or to the neck, lower jaw, and interscapular space. Atypical irradiation of pain is rarely observed - in the epigastrium, the left half of the celiac region. At the time of the onset of the attack, the patient, as a rule, freezes; if the pain occurred while walking, he stops. Objectively, in a severe attack, hyperemia or pallor of the face, the appearance of droplets of sweat on it, sometimes increased sweating on the body, slight tachycardia , a slight increase or decrease in blood pressure, dilated pupils can be observed. Reception of nitroglycerin in the vast majority of cases completely stops the attack within 1-2 minutes.
With spontaneous angina pectoris, there is no connection between a pain attack and physical activity. In a number of patients, as in many patients with exertional angina, attacks are provoked by psycho-emotional stress. Attacks of spontaneous angina are very long (15 to 20 minutes), with them often observed ventricular extrasystole. The effectiveness of nitroglycerin for stopping the attack is small, the pain is more easily stopped by nifedipine (Corinfar, Adalat, Kordafen), the tablet (or capsule) of which should be chewed and kept in the mouth until completely resorbed.
The course of angina pectoris largely depends on the severity and rate of progression of coronary artery disease, which underlies coronary insufficiency. In some cases, the functional class of angina pectoris may remain unchanged for many years, in others there is a slow, but constant increase in symptoms. Angina pectoris of any functional class, as it first appeared, can, for reasons not always known, suddenly acquire a rapidly progressive course and result in myocardial infarction.
The diagnosis is based on the relationship of the pain attack with the load or other provoking factor, the paroxysmal nature of the pain syndrome with a clear onset and end of the attack, relatively short duration, quick (usually within 2 minutes) stopping the action of nitroglycerin. Additional signs - the nature of the pain, its localization and irradiation - may vary.
Despite the fact that in the overwhelming majority of cases, angina pectoris proceeds quite typically, to date errors related to its hyper- or hypodiagnosis are widespread. Pain in the chest can be associated with many diseases or pathological conditions (pericarditis, pleurisy , myalgia and myositis , plexitis , neuritis , neuralgia , esophagitis , diaphragmatic hernia, herpes zoster , etc.). However, in all these conditions, the pain is not clearly paroxysmal in nature, is not associated with such forms of load as walking or climbing stairs (with lesions of the nervous system or musculoskeletal system, it can occur or intensify with certain movements, for example, turning the body, raising the arms ), not inferior to the action of nitroglycerin.
A number of special methods are used to confirm the diagnosis. If it is possible to register a standard ECG at the height of a pain attack, then in most cases a characteristic ischemic (horizontal or oblique) depression of the ST segment is detected, which confirms the diagnosis. For this purpose, also use daily ECG monitoring.
In the diagnosis using methods based on the artificial provocation of an attack of angina pectoris. The bicycle ergometric test with a dosed stepwise increasing load is quite informative. The appearance of ST segment depression during the test objectifies the diagnosis. The physiological test used mainly in hospitals is a stress test on a treadmill (treadmill) with a changing speed and angle of inclination. For some concomitant diseases, carrying out bicycle ergometry or a treadmill test is impossible or the results of these tests are difficult to interpret. In such cases, transesophageal electrical stimulation of the atria is performed in cardiological hospitals with a smooth increase in incentives until the heart rate reaches which ECG changes characteristic of ischemia appear. To verify the diagnosis of spontaneous angina pectoris, the most informative continuous monitoring of ECG is with the help of portable devices, which is also used to diagnose angina pectoris. In the latter case, at the time of the attack, a horizontal or skew-downward shift of the ST segment down from the isoelectric line is recorded; and in the classic form of spontaneous angina (Prinzmetal angina), transient ST segment elevation is noted.
Treatment of angina pectoris includes urgent measures to relieve an attack and the constant implementation of medical recommendations by patients aimed at reducing the frequency and severity of angina attacks.
Relief of an attack with stable angina pectoris reduces to an immediate cessation of physical activity and obligatory taking nitroglycerin tablets under the tongue, even if the patient knows from his own experience that the pain goes away with the cessation of the load. The need for the use of nitroglycerin is dictated by the fact that according to the initial subjective manifestations of an anginal attack, one cannot predict how it will proceed and whether it will turn into an anginal status. The most convenient and effective tablet form of nitroglycerin; its effect reaches a maximum within 1 - 1.5 minutes after administration under the tongue. If taking one tablet of nitroglycerin did not stop the pain, after 2 to 3 minutes you need to take a second tablet; in this case, the patient should take a lying or reclining position. If nitroglycerin causes a very severe headache, you can recommend that the patient always have some sugar cubes with him, each of which is moistened with 6-8 drops of a 0.1% solution of nitroglycerin in a 3% alcohol solution of menthol (Votchal drops), and dissolve when pain occurs such a piece. Many patients prefer to take validol, but it is much less effective than nitroglycerin . If nitroglycerin is poorly tolerated, it is advisable to try to stop the seizures by resorption of a nitrosorbide tablet (10 mg) or chewing a Corinfar tablet (10 mg). The latter is the means of choice for stopping an attack of spontaneous angina pectoris, in which nitroglycerin is less effective.
With progressive angina pectoris, they try to stop a pain attack by all available means. Without waiting for the pain to intensify, it is necessary to immediately take a nitroglycerin tablet under the tongue and, if this is not enough, you need to take another 2 to 3 tablets with intervals between doses of about 2 minutes. The total daily dose of nitroglycerin is not limited. If nitroglycerin is ineffective, narcotic analgesics (promedol, omnopon , morphine, fentanyl) are administered parenterally for 15 to 20 minutes. Rapidly progressive angina pectoris, including the first occurrence, is an absolute indication for urgent hospitalization. Scheduled hospitalization is indicated for severe angina pectoris of functional tension class III — IV for the selection of therapy or the resolution of the issue of surgical treatment.
Continuous treatment of patients with angina pectoris is largely carried out under the subjective control of the patient himself, who must therefore be correctly informed about the nature of the disease and the criteria for evaluating its course, tactics of behavior during exacerbations and remissions of the disease. The patient needs to be told about the conditions in which the occurrence of an anginal attack is most likely, to emphasize that the disease has a chronic course and requires constant treatment. It is necessary in an accessible form, trying not to intimidate the patient, to explain to him that with an acute increase in frequency, lengthening and increase in severity of attacks, as well as with. development of their insensitivity to nitroglycerin, he must immediately seek emergency medical attention.
For the treatment of stable angina pectoris, a large number of drugs have been proposed for various chemical and pharmacological groups. The three drugs are most widely used: nitrates, beta-adrenoreceptor blockers and calcium ion antagonists.
Of the nitro drugs to prevent angina attacks, dosage forms of prolonged action nitroglycerin for parenteral use in the form of a patch, ointment, buccal plates, etc. are widely used. Such drugs as Sustak , Nitrong , Sustanit, are ineffective, since the nitroglycerin contained in them is almost completely destroyed when passing through the liver. For oral administration, isosorbide dinitrate preparations (nitrosorbide, isodinite retard, cardicet, etc.), isosorbide-5-mononitrate (isomak, etc.) are effective. Doses of these drugs vary widely, they are selected taking into account clinical efficacy. The main disadvantage of nitrates is a gradual decrease in their effectiveness with prolonged use ("addiction"), which, according to some reports, is less inherent in dosage forms for application to the skin (nitromaz, nitro plasters) or gums (trinitrolong). Nitrosorbide, the effect of a single dose of which lasts 4 to 6 hours, is recommended to be taken at least 4 times a day (10 to 80 mg per dose), prolonged forms of nitrates are sufficient to take 2 times a day. It is close to nitro drugs by the pharmacological action and in some cases replaces them with molsidomine , which is prescribed orally by 1-4 mg 3-4 times a day. All nitro drugs can cause severe headaches. In such cases, treatment begins with minimal doses, which are gradually increased. It is advisable to prescribe Votchala drops on sugar for 2 to 3 weeks before starting treatment with a nitrodrug (starting with 1-2 drops on a piece of sugar and gradually bringing a single dose to 8-10 drops 4 times a day). In angina pectoris of I-II functional classes, nitrates are used only “on demand” for the relief of pain attacks; III-IV functional classes - prolonged forms of drugs are taken continuously.
Beta-blockers are effective in treating angina pectoris, which reduce myocardial oxygen demand and increase patients' exercise tolerance. The properties of beta-blockers, such as their antiarrhythmic and anti-fibrillatory effect, and the ability in many cases to reduce high blood pressure, are very important for the treatment of patients with angina pectoris. The most widely used anaprilin (propranolol, inderal, obzidan) in doses of 10 to 40 mg 4-6 times a day. With angina pectoris, anaprilin is prescribed 4 times a day. Anaprilin refers to non-selective beta-blockers, the use of which is contraindicated in bronchospasm, as well as in obliterating and angioedema of limb vessels (atherosclerosis, endarteritis, Raynaud's disease, etc.). These contraindications are less significant for the so-called cardioselective drugs of this group, the effect of which in usual doses is limited by the blockade of mainly myocardial beta-adrenoreceptors (in high doses, the selectivity of action decreases). Selective beta-blockers include metoprolol (spesicor), atenolol . Atenolol has a longer duration of action (0.05 - 0.1 g of the drug is sometimes enough to take once a day), metoprolol is somewhat less prolonged (0.025 - 0.1 g 2 times a day). If the listed drugs cause severe bradycardia, it is advisable to try taking beta-blockers with the so-called internal sympathomimetic action, for example, sectral, which very rarely slows down and can even increase the heart rate. All beta-blockers are able to inhibit atrioventricular conduction, so treatment with them, especially at first, should be carried out under electrocardiographic control (additional suppression of impaired conduction may be absent). It is extremely important to take into account that a sudden cessation of beta-blockers can cause withdrawal syndrome - a sharp exacerbation of angina pectoris and even the development of myocardial infarction, therefore, if necessary, their withdrawal dose is reduced gradually, while supplementing drug therapy with drugs from other groups.
Of the drugs belonging to the group of calcium antagonists, verapamil (isoptin, finoptin) and nifedipine (corinfar) are most often used. Verapamil has moderate antiarrhythmic activity and is preferred when combining angina pectoris with cardiac arrhythmias. It is prescribed in a dose of 80-120 mg 3-4 times a day (isoptin retard - 1 time per day), and after 2 to 3 months after the start of treatment, the dose can be gradually reduced, bringing it to 160-120 g per day. Treatment with verapamil in high doses requires electrocardiographic monitoring, since inhibition of atrioventricular conduction is possible. Nifedipine at a dose of 10 - 20 mg 3-4 times a day is a means of choice in the treatment of spontaneous angina pectoris, in which nitro drugs are less effective, and the appointment of beta-blockers, according to some authors, is undesirable due to their possible development of angiospasm. For angina pectoris, a long-acting drug from the same group, amlodipine (norvask), which is prescribed 5 to 10 mg per day, is used.
Acetylsalicylic acid (aspirin) is used as an anti-aggregation agent, the use of which at 0.125 g once a day significantly reduces the risk of developing myocardial infarction in patients.
Treatment of patients with progressive angina pectoris is carried out only in a hospital with a stricter than usual restriction of the motor regime (loads that cause angina attacks should be completely excluded). Partial nutrition and a diet containing digestible foods are recommended. It is important to monitor the regularity of the stool, if necessary, use laxatives and enemas, since straining during bowel movements often causes a severe attack of angina pectoris. Doses of antianginal drugs are increased to the maximum tolerated by patients. To prevent myocardial infarction, acetylsalicylic acid must be prescribed. In many cases, the use of heparin under the control of blood coagulation gives a positive effect. A gradual decrease in the doses of antianginal drugs and the expansion of the motor regime are permissible only after the regression of symptoms and stabilization of the condition.
Forecast Stable angina pectoris often over the years has no tendency to progression. Patients with angina pectoris I — II functional class, as a rule, can perform work that does not require physical stress. With first-time and progressive angina, the prognosis is uncertain; progressive angina pectoris in more than half of cases ends with the development of myocardial infarction. Surgical treatment for angina of the III – IV functional class can improve the prognosis.
Prevention coincides with the prevention of coronary heart disease. Physical therapy (especially dosed walking) contributes to the creation of conditions for the development of collateral circulation in the system of coronary arteries of the heart. Patients with stable exertional angina are recommended daily walking (5-10 km) at a pace that does not cause seizures. It is very important to exclude smoking , but for long-term smokers this should be done with caution, since if a patient who smoked 20 cigarettes a day or more for many years immediately stops smoking, a sharp exacerbation of the disease and even the development of myocardial infarction are possible. In such cases, it is advisable to reduce the number of daily smoked cigarettes (cigarettes) gradually. Alcohol abuse is unacceptable.