Causes of chest pain

The main causes of chest pain:

• diseases of the musculoskeletal system: costal chondritis, rib fracture;
• cardiovascular diseases: ischemia of the heart caused by atherosclerosis of the vessels of the heart; unstable / stable angina pectoris; cardiac ischemia caused by coronary vasospasm (angina pectoris); mitral valve prolapse syndrome; cardiac arrhythmia; pericarditis.
• gastrointestinal diseases: gastroesophageal reflux, esophageal spasm, stomach and duodenal ulcers, gallbladder disease;
• anxiety states: vague anxiety or "stress", panic disorder;
• pulmonary diseases: pleurodynia (pleuralgia), acute bronchitis, pneumonia;
• neurological diseases;
• uncharacteristic definite or atypical chest pain.

Chest pain is not limited to a specific age group, but is more common in adults than in children. The highest percentage is observed among adults over 65 years old, followed by male patients aged 45 to 65 years.

Frequency of diagnosis, by age and sex

Floor	Age group (years)	Most common diagnoses
Men	18-24	1. Gastroesophageal reflux
		2. Muscle pain of the chest wall
	2 & 44	1. Gastroesophageal reflux
		2. Muscle pain of the chest wall
		3. Costal chondritis
	45-64	1. Angina pectoris, unstable angina pectoris, myocardial infarction
		2. Muscle pain of the chest wall
		3. "Atypical" chest pain
	65 and more	1. Muscle pain of the chest wall
		2. "Atypical" chest pain or coronary arterial disease
Women	18-24	1. Costal chondritis
		2. Anxiety / stress
	25-44	1. Muscle pain of the chest wall
		2. Costal chondrite
		3. "Atypical" chest pain
		4. Gastroesophageal reflux
	45-64	1. Angina pectoris, unstable angina pectoris, myocardial infarction
		2. "Atypical" chest pain
		3. Muscle pain of the chest wall
	65 and more	1. Angina pectoris, unstable angina pectoris, myocardial infarction
		2. Muscle pain of the chest wall
		3. "Atypical" chest pain or costal chondritis

No less difficult is the position of the doctor in the initial interpretation of pain, when he tries to associate it with the pathology of a particular organ. The observation of clinicians of the last century helped them formulate assumptions about the pathogenesis of pain - if an attack of pain occurs without a cause and stops on its own, then the pain is probably of a functional nature. There are few works devoted to the detailed analysis of chest pain; groupings of pains offered in them are far from perfect. These shortcomings are due to the objective difficulties in analyzing the patient's feelings.

The complexity of the interpretation of pain in the chest is also due to the fact that the detected pathology of one or another organ of the chest or musculoskeletal formation does not mean that it is she who is the source of pain; in other words, the identification of a disease does not mean that the cause of the pain is precisely determined.

When evaluating patients with chest pain, the clinician must weigh all relevant options for potential causes of pain, determine when intervention is necessary, and choose from a virtually limitless number of diagnostic and therapeutic strategies. All of this needs to be done while simultaneously responding to the distress experienced by patients concerned with a life-threatening illness. The difficulty in diagnosis is further complicated by the fact that chest pain is often a complex interplay of psychological, pathological and psychosocial factors. This makes it the most common problem in primary care.

When considering chest pain, there are (at least) the following five elements: predisposing factors; characteristics of an attack of pain; duration of painful episodes; a description of the pain itself; pain relieving factors.

With all the variety of reasons that cause pain in the chest, pain syndromes can be grouped.

The approaches to groupings can be different, but basically they are built on the nosological or organ principle.

Conventionally, 6 following groups can be distinguished:

1. Pain due to heart disease (called heart pain). These painful sensations can be the result of damage or dysfunction of the coronary arteries - coronary artery pain. The "coronary component" is not involved in the origin of non-coronary pain. In the future, we will use the terms "heart pain syndrome", "heart pain", understanding their connection with one or another heart pathology.
2. Pain caused by pathology of large vessels (aorta, pulmonary artery and its branches).
3. Pain caused by pathology of the bronchopulmonary apparatus and pleura.
4. Pain associated with pathology of the spine, anterior chest wall and muscles of the shoulder girdle.
5. Pain due to the pathology of the mediastinal organs.
6. Pain associated with diseases of the abdominal organs and pathology of the diaphragm.

Pain is also divided into acute and long-term, with a clear cause and no apparent reason, "harmless" and pains that serve as a manifestation of life-threatening conditions. Naturally, the first step is to establish whether the pain is dangerous or not. "Dangerous" pains include all types of anginal (coronary) pain, pain in pulmonary embolism (PE), dissecting aortic aneurysm, spontaneous pneumothorax. To "non-dangerous" - pain in the pathology of intercostal muscles, nerves, bone-cartilaginous formations of the chest. "Dangerous" pains are accompanied by a suddenly developed serious condition or severe disorders of the heart or breathing, which immediately allows you to narrow the range of possible diseases (acute myocardial infarction, PE, dissecting aortic aneurysm, spontaneous pneumothorax).

The main life-threatening causes of acute chest pain are:

• cardiological: acute or unstable angina pectoris, myocardial infarction, dissecting aortic aneurysm;
• pulmonary: pulmonary embolism; tense pneumothorax.

It should be noted that the correct interpretation of chest pain is quite possible with a routine physical examination of the patient using a minimum number of instrumental methods (conventional electrocardiographic and X-ray examination). An erroneous initial idea of the source of pain, in addition to increasing the period of examination of the patient, often leads to serious consequences.

History and physical examination to determine the cause of chest pain

Anamnesis data	Diagnostic category
	Cardiac	Gastrointestinal	Musculoskeletal
Predisposing factors	Male. Smoking. High blood pressure. Hyperlipidemia. Family history of myocardial infarction	Smoking. Alcohol consumption	Physical activity. A new kind of activity. Abuse. Repetitive actions
Characteristics of a pain attack	With high levels of tension or emotional stress	After eating and / or on an empty stomach	When active or after
Duration of pain	Minutes	From min. Until hours	From hours to days
Pain characteristic	Pressure or "burning"	Pressure or boring "pain"	Acute, localized, caused by movement
Factors Filming Pain	Recreation. Nitro preparations under the tongue	Taking food. Antacids. Antihistamines	Recreation. Analgesics. Non-steroidal anti-inflammatory drugs
Supporting data	With attacks of angina pectoris, rhythm disturbances or noises are possible	Soreness in the epigastric region	Pain on palpation at the paravertebral points, at the exit sites of the intercostal nerves, tenderness of the periosteum

Cardialgia (non-anginal pain). Cardialgias caused by certain heart diseases are very common. By its origin, significance and place in the structure of the morbidity of the population, this group of pains is extremely heterogeneous. The causes of such pain and their pathogenesis are very diverse. Diseases or conditions in which cardialgias are observed are as follows:

1. Primary or secondary cardiovascular functional disorders - the so-called neurotic-type cardiovascular syndrome or neurocirculatory dystonia.
2. Diseases of the pericardium.
3. Inflammatory diseases of the myocardium.
4. Dystrophy of the heart muscle (anemia, progressive muscular dystrophy, alcoholism, vitamin deficiency or starvation, hyperthyroidism, hypothyroidism, catecholamine effects).

As a rule, non-anginal pain is benign, since it is not accompanied by coronary insufficiency and does not lead to the development of ischemia or myocardial necrosis. However, in patients with functional disorders leading to an increase (usually short-term) in the level of biologically active substances (catecholamines), the likelihood of ischemia still exists.

Chest pains of neurotic origin. We are talking about pain in the pain of the heart, as one of the manifestations of neurosis or neurocirculatory dystonia (vegetative-vascular dystonia). Usually these are pains of a aching or stabbing nature, of varying intensity, sometimes long-term (hours, days) or, conversely, very short-term, instantaneous, piercing. The localization of these pains is very different, not always constant, almost never retrosternal. Pain can increase with physical exertion, but usually with psychoemotional stress, fatigue, without a clear effect of the use of nitroglycerin, it does not decrease at rest, and sometimes, on the contrary, patients feel better when moving. The diagnosis takes into account the presence of signs of a neurotic state, autonomic dysfunction (sweating, dermographism, subfebrile condition, fluctuations in the pulse and blood pressure), as well as the young or middle age of patients, mainly female. These patients have increased fatigue, decreased exercise tolerance, anxiety, depression, phobias, pulse fluctuations, blood pressure. In contrast to the severity of subjective disorders, objective research, including using various additional methods, does not reveal a specific pathology.

Sometimes, among these symptoms of neurotic origin, the so-called hyperventilation syndrome is revealed. This syndrome is manifested by an arbitrary or involuntary increase and deepening of respiratory movements, tachycardia, arising in connection with unfavorable psychoemotional influences. In this case, chest pains may occur, as well as paresthesias and muscle twitching in the limbs in connection with the resulting respiratory alkalosis. There are observations (incompletely confirmed), indicating that hyperventilation can lead to a decrease in myocardial oxygen consumption and provoke coronary spasm with pain and ECG changes. It is possible that it is hyperventilation that can cause pain in the heart area during exercise testing in individuals with vegetative-vascular dystonia.

To diagnose this syndrome, a provocative test with induced hyperventilation is performed. The patient is asked to breathe more deeply - 30-40 times per minute for 3-5 minutes or until the symptoms usual for the patient appear (chest pains, headaches, dizziness, shortness of breath, sometimes fainting). The appearance of these symptoms during the test or 3-8 minutes after its completion with the exclusion of other causes of pain has a very definite diagnostic value.

Hyperventilation in some patients may be accompanied by aerophagia with the appearance of pain or a feeling of heaviness in the upper part of the epigastric region due to distension of the stomach. These pains can spread upward, behind the sternum, into the neck and the area of the left shoulder blade, simulating angina pectoris. Such pains increase with pressure on the epigastric region, in the prone position, with deep breathing, and decrease with belching with air. With percussion, an expansion of the Traube space zone is found, including tympanitis over the area of absolute dullness of the heart, with fluoroscopy - an enlarged gastric bladder. Similar pain can occur when the left corner of the colon is distended with gases. In this case, the pain is often associated with constipation and is relieved after a bowel movement. A careful history usually helps to determine the true nature of the pain.

The pathogenesis of cardiac pain in neurocirculatory dystonia is unclear, due to the impossibility of their experimental reproduction and confirmation in the clinic and experiment, in contrast to anginal pain. Perhaps, in connection with this circumstance, a number of researchers generally question the presence of pain in the heart in neurocirculatory dystonia. Such tendencies are most common among representatives of the psychosomatic direction in medicine. According to their views, we are talking about the transformation of psychoemotional disorders into a painful sensation.

The origin of pain in the heart in neurotic conditions is also explained from the standpoint of the cortico-visceral theory, according to which, when the autonomic devices of the heart are irritated, a pathological dominant arises in the central nervous system with the formation of a vicious circle. There is reason to believe that heart pain in neurocirculatory dystonia occurs due to a violation of myocardial metabolism against the background of excessive adrenal stimulation. At the same time, there is a decrease in the content of intracellular potassium, activation of dehydrogenation processes, an increase in the level of lactic acid and an increase in myocardial oxygen demand. Hyperlactatemia is a well-proven fact in neurocirculatory dystonia.

Clinical observations showing a close relationship between pain in the region of the heart and emotional influences confirm the role of catecholamines as a trigger for pain. This position is supported by the fact that with intravenous administration of izadrin to patients with neurocirculatory dystonia, they experience pain in the region of the heart such as cardialgia. Obviously, catecholamine stimulation can also explain the provocation of cardialgia by a test with hyperventilation, as well as its occurrence at the height of respiratory disorders in neurocirculatory dystonia. This mechanism can also be confirmed by the positive results of the treatment of cardialgia with breathing exercises aimed at eliminating hyperventilation. A certain role in the formation and maintenance of cardiac pain in neurocirculatory dystonia is played by the flow of pathological impulses coming from the zones of hyperalgesia in the area of the muscles of the anterior chest wall to the corresponding segments of the spinal cord, where, according to the "portal" theory, the phenomenon of summation occurs. In this case, a reverse flow of impulses is noted, causing irritation of the thoracic sympathetic ganglia. Of course, the low threshold of pain sensitivity in vegetative-vascular dystonia is also important.

In the onset of pain, such factors, as yet insufficiently studied, can play a role, such as impaired microcirculation, changes in the rheological properties of blood, an increase in the activity of the kininkallikrein system. It is possible that with the long-term existence of severe vegetative-vascular dystonia, its transition to ischemic heart disease with unchanged coronary arteries is possible, in which pain is caused by spasm of the coronary arteries. In a directed study of a group of patients with proven coronary artery disease with unaltered coronary arteries, it was found that all of them in the past suffered from severe neurocirculatory dystonia.

In addition to vegetative-vascular dystonia, cardialgia is observed in other diseases, but the pain is less pronounced and usually never comes to the fore in the clinical picture of the disease.

The origin of pain in case of damage to the pericardium is quite understandable, since there are sensitive nerve endings in the pericardium. Moreover, it has been shown that irritation of certain zones of the pericardium gives different localization of pain. For example, irritation of the pericardium on the right causes pain along the right mid-clavicular line, and irritation of the pericardium in the region of the left ventricle is accompanied by pain that spreads along the inner surface of the left shoulder.

Pain with myocarditis of various origins is a very common symptom. Their intensity is usually low, but in 20% of cases they have to be differentiated from pain caused by coronary artery disease. Pain in myocarditis is probably associated with irritation of the nerve endings located in the epicardium, as well as with inflammatory myocardial edema (in the acute phase of the disease).

Even more uncertain is the origin of pain in myocardial dystrophies of various origins. Probably, the pain syndrome is caused by a violation of myocardial metabolism, the concept of local tissue hormones convincingly presented by N.R. Paleev et al. (1982) may also shed light on the causes of pain. In some myocardial dystrophies (due to anemia or chronic carbon monoxide poisoning), pain can be of mixed origin, in particular, the ischemic (coronary) component is essential.

It is necessary to dwell on the analysis of the causes of pain in patients with myocardial hypertrophy (due to pulmonary or systemic hypertension, valvular heart disease), as well as in primary cardiomyopathies (hypertrophic and dilated). Formally, these diseases are mentioned in the second heading of anginal pain caused by an increase in myocardial oxygen demand with unchanged coronary arteries (the so-called non-coronary forms). However, with these pathological conditions, in a number of cases, unfavorable hemodynamic factors arise, causing relative myocardial ischemia. It is believed that the angina-type pain observed in aortic regurgitation depends primarily on low diastolic pressure and, consequently, low coronary perfusion (coronary blood flow occurs during diastole).

With aortic stenosis or idiopathic myocardial hypertrophy, the appearance of pain is associated with impaired coronary circulation in the subendocardial regions due to a significant increase in intramyocardial pressure. All painful sensations in these diseases can be designated as metabolic or hemodynamically caused anginal pain. Despite the fact that they do not formally belong to ischemic heart disease, one should bear in mind the possibility of developing small focal necrosis. At the same time, the characteristics of these pains often do not correspond to classical angina pectoris, although typical attacks are also possible. In the latter case, the differential diagnosis with coronary artery disease is especially difficult.

In all cases of detection of non-coronary causes of chest pain, it is taken into account that their presence does not at all contradict the simultaneous existence of coronary artery disease and, accordingly, requires an examination of the patient in order to exclude or confirm it.

Chest pain caused by the pathology of the bronchopulmonary apparatus and pleura. Pain quite often accompanies a variety of pulmonary pathologies, occurring in both acute and chronic diseases. However, it is usually not the leading clinical syndrome and is easily differentiated.

The source of pain is the parietal pleura. From pain receptors located in the parietal pleura, afferent fibers are part of the intercostal nerves, so the pain is clearly localized on the affected half of the chest. Another source of pain is the mucous membrane of the large bronchi (which is well proven with bronchoscopy) - afferent fibers from the large bronchi and trachea are part of the vagus nerve. The mucous membrane of the small bronchi and pulmonary parenchyma probably does not contain pain receptors, therefore, pain in the primary lesion of these formations appears only when the pathological process (pneumonia or tumor) reaches the parietal pleura or spreads to the large bronchi. The most severe pains are noted during the destruction of lung tissue, sometimes acquiring high intensity.

The nature of pain sensations to some extent depends on their origin. Pain with damage to the parietal pleura is usually stabbing, clearly associated with coughing and deep breathing. Dull pain is associated with stretching of the mediastinal pleura. Severe, persistent pain, aggravated by breathing, movement of the arms and shoulder girdle, may indicate the growth of a tumor into the chest.

The most common causes of pulmonary pleural pain are pneumonia, lung abscess, tumors of the bronchi and pleura, pleurisy. With pain associated with pneumonia, dry or exudative pleurisy during auscultation, wheezing in the lungs, pleural friction noise can be detected.

Severe pneumonia in adults has the following clinical features:

• moderate or severe depression of respiratory function;
• temperature 39.5 ° C or higher;
• confusion of consciousness;
• respiratory rate - 30 per minute or more;
• pulse 120 beats per minute or more;
• systolic blood pressure below 90 mm Hg. Art.;
• diastolic blood pressure below 60 mm Hg. Art.;
• cyanosis;
• over 60 years of age - features: confluent pneumonia, is more severe with concomitant severe diseases (diabetes, heart failure, epilepsy).

NB! All patients with signs of severe pneumonia should be referred to hospital immediately! Hospital referral:

• severe pneumonia;
• patients with pneumonia from socio-economically disadvantaged segments of the population, or who are unlikely to follow doctor's prescriptions at home; who live very far from the medical facility;
• pneumonia in combination with other diseases;
• suspicion of SARS;
• patients who do not respond positively to treatment.

Pneumonia in children is described as follows:

• retraction of the intercostal spaces of the chest, cyanosis and inability to drink in young children (from 2 months to 5 years) also serves as a sign of a severe form of pneumonia, in which an urgent referral to the hospital is required;
• it is necessary to distinguish pneumonia from bronchitis: the most valuable sign in the case of pneumonia is tachypnea.

Pain in the defeat of the pleura almost does not differ from those in acute intercostal myositis or injury to the intercostal muscles. With spontaneous pneumothorax, there is an acute unbearable chest pain associated with damage to the bronchopulmonary apparatus.

Chest pain, difficult to interpret due to its uncertainty and isolation, is observed in the early stages of bronchogenic lung cancer. The most excruciating pain is characteristic of the apical localization of lung cancer, when damage to the common trunk of the CVII and ThI nerves and brachial plexus develops almost inevitably and rapidly. The pain is localized mainly in the brachial plexus and radiates along the outer surface of the arm. Horner's syndrome (constriction of the pupil, ptosis, enophthalmos) often develops on the side of the lesion.

Pain syndromes also occur with mediastinal localization of cancer, when compression of the nerve trunks and plexuses causes acute neuralgic pain in the shoulder girdle, upper limb, and chest. This pain gives rise to an erroneous diagnosis of angina pectoris, myocardial infarction, neuralgia, plexitis.

The need for differential diagnosis of pain caused by damage to the pleura and bronchopulmonary apparatus, with coronary artery disease arises in cases when the picture of the underlying disease is unclear and pain comes to the fore. In addition, a similar differentiation (especially in acute unbearable pain) should be carried out with diseases caused by pathological processes in large vessels - PE, stratifying aneurysm of various parts of the aorta. Difficulties in identifying pneumothorax as the cause of acute pain are associated with the fact that in many cases the clinical picture of this acute situation is erased.

Pain associated with the pathology of the mediastinal organs is caused by diseases of the esophagus (spasm, reflux esophagitis, diverticula), mediastinal tumors and mediastinitis.

Pain in diseases of the esophagus usually has a burning character, is localized behind the fudina, occurs after eating, and intensifies in a horizontal position. Such common symptoms as heartburn, belching, swallowing disorders may be absent or mild, and chest pains, often occurring during physical exertion and inferior to the action of nitroglycerin, come to the fore. The similarity of these pains with angina pectoris is complemented by the fact that they can radiate to the left half of the chest, shoulders, arms. On closer inquiry, however, it turns out that pain is more often associated with food, especially plentiful, and not with physical activity, usually occurs in the supine position and disappears or is relieved when moving to a sitting or standing position, when walking, after taking antacids. For example soda, which is uncommon for ischemic heart disease. Often, palpation of the epigastric region intensifies these pains.

Chest pain is also suspicious for gastroesophageal reflux and esophagitis. To confirm the presence of which 3 types of tests are important: endoscopy and biopsy; intraesophageal infusion of 0.1% hydrochloric acid solution; monitoring of intraesophageal pH. Endoscopy is important to detect reflux, esophagitis, and to rule out other pathologies. X-ray examination of the esophagus with barium reveals anatomical changes, but its diagnostic value is considered relatively low due to the high frequency of false-positive signs of reflux. With the perfusion of hydrochloric acid (120 drops per minute through a probe), the appearance of pain common to the patient is important. The test is considered highly sensitive (80%), but not specific enough, which, if the results are unclear, requires repeated studies.

In case of unclear results of endoscopy and perfusion of hydrochloric acid, monitoring of intraesophageal pH can be carried out using a radiotelemetric capsule placed in the lower part of the esophagus for 24-72 hours. Really a criterion for the origin of esophageal pain.

Chest pains, similar to angina pectoris, may also be the result of an increase in the motor function of the esophagus with achalasia (spasm) of the cardiac region or diffuse spasm. Clinically, in such cases, there are usually signs of dysphagia (especially when taking solid food, cold liquids), which, in contrast to organic stenosis, has an unstable character. Sometimes chest pains of varying duration come to the fore. Difficulties in differential diagnosis are also due to the fact that this category of patients is sometimes helped by nitroglycerin, which relieves spasm and pain.

Radiographically, with achalasia of the esophagus, an expansion of its lower part and a retention of barium mass in it are found. However, X-ray examination of the esophagus in the presence of pain is not very informative, or rather, it is not very indicative: false-positive results were noted in 75% of cases. It is more effective to conduct esophageal manometry using a three-lumen probe. The coincidence in the time of the onset of pain and the increase in intraesophageal pressure has a high diagnostic value. In such cases, there may be a positive effect of nitroglycerin and calcium antagonists, which reduce smooth muscle tone and intraesophageal pressure. Therefore, these drugs can be used in the treatment of such patients, especially in combination with anticholinergics.

Clinical experience suggests that with esophageal pathology, ischemic heart disease is often misdiagnosed. In order to make a correct diagnosis, the doctor should look for other symptoms of esophageal disorders in the patient and compare the clinical manifestations and the results of various diagnostic tests.

Attempts to develop a set of instrumental studies that would help distinguish between anginal and esophageal pain were unsuccessful, since a combination of this pathology with angina pectoris is often found, which is confirmed by bicycle ergometry. Thus, despite the use of various instrumental methods, the differentiation of pain sensations is still very difficult.

Mediastinitis and mediastinal tumors are uncommon causes of chest pain. Usually, the need for differential diagnosis with ischemic heart disease arises at pronounced stages of tumor development, when, however, there are still no pronounced symptoms of compression. The appearance of other signs of the disease greatly facilitates the diagnosis.

Chest pain in diseases of the spine. Pain in the chest can also be associated with degenerative changes in the spine. The most common disease of the spine is osteochondrosis (spondylosis) of the cervical and thoracic spine, in which there is pain, sometimes similar to angina pectoris. This pathology is widespread, since after 40 years, changes in the spine are often observed. With damage to the cervical and (or) upper thoracic spine, the development of a secondary radicular syndrome with the spread of pain in the chest area is often observed. These pains are associated with irritation of the sensory nerves by osteophytes and thickened intervertebral discs. Usually, in this case, bilateral pains appear in the corresponding intercostal spaces, but patients quite often concentrate their attention on their retrosternal or pericardial localization, referring them to the heart. Such pains can be similar to angina pectoris in the following ways: they are perceived as a feeling of pressure, heaviness, sometimes radiating to the left shoulder and arm, neck, can be provoked by physical exertion, accompanied by a feeling of shortness of breath due to the impossibility of deep breathing. Taking into account the elderly age of patients in such cases, the diagnosis of ischemic heart disease is often made with all the ensuing consequences.

At the same time, degenerative changes in the spine and the pain caused by them can be observed in patients with undoubted coronary artery disease, which also requires a clear delineation of the pain syndrome. Perhaps, in some cases, angina attacks against the background of atherosclerosis of the coronary arteries in patients with spinal lesions also occur reflexively. The unconditional recognition of this possibility, in turn, transfers the "center of gravity" to the pathology of the spine, reducing the importance of independent damage to the coronary arteries.

How to avoid a diagnostic error and make a correct diagnosis? Of course, it is important to conduct an X-ray of the spine, but the changes detected in this case are completely insufficient for diagnosis, since these changes can only accompany coronary artery disease and (or) not manifest clinically. Therefore, it is very important to find out all the features of pain. As a rule, pain depends not so much on physical activity as on changes in body position. The pain is often aggravated by coughing, deep breathing, and may decrease in some comfortable position of the patient, after taking analgesics. These pains differ from angina pectoris in a more gradual onset, longer duration, they do not go away at rest and after the use of nitroglycerin. Irradiation of pain in the left hand occurs along the dorsal surface, in the I and II fingers, while with angina pectoris - in the IV and V fingers of the left hand. Of certain importance is the detection of local painfulness of the spinous processes of the corresponding vertebrae (trigger zone) when pressing or tapping paravertebrally and along the intercostal space. Pain can also be caused by certain techniques: strong pressure on the head towards the back of the head or stretching one arm while turning the head to the other side. With veloergometry, pain in the region of the heart may appear, but without characteristic ECG changes.

Thus, the diagnosis of radicular pain requires a combination of radiological signs of osteochondrosis and the characteristic features of chest pain that do not correspond to coronary heart disease.

The frequency of muscle-fascial (muscular-dystonic. Muscular-dystrophic) syndromes in adults is 7-35%, and in some professional groups it reaches 40-90%. With some of them, heart disease is often mistakenly diagnosed, since the pain syndrome in this pathology has some resemblance to pain in cardiac pathology.

There are two stages of the disease of muscle-fascial syndromes (Zaslavsky E.S., 1976): functional (reversible) and organic (muscular-dystrophic). There are several etiopathogenetic factors in the development of muscle-fascial syndromes:

1. Injuries of soft tissues with the formation of hemorrhages and serofibrinous extravasates. As a result, compaction and shortening of muscles or individual muscle bundles, ligaments, and a decrease in the elasticity of the fascia develop. As a manifestation of the aseptic inflammatory process, connective tissue is often formed in excess.
2. Microtraumatization of soft tissues in some types of professional activity. Microtraumas disrupt tissue circulation, cause muscle-tonic dysfunction with subsequent morphological and functional changes. This etiological factor is usually combined with others.
3. Pathological impulses in visceral lesions. This impulse, which occurs when the internal organs are damaged, is the cause of the formation of various sensory, motor and trophic phenomena in the integumentary tissues, which are innervationally associated with the altered internal organ. Pathological interoceptive impulses, switching through the spinal segments, go to the connective tissue and muscle segments corresponding to the affected internal organ. The development of muscle-fascial syndromes associated with cardiovascular pathology can change the pain syndrome so much that diagnostic difficulties arise.
4. Vertebrogenic factors. When the receptors of the affected motor segment are irritated (receptors of the annulus fibrosus of the intervertebral disc, the posterior longitudinal ligament, joint capsules, autochthonous muscles of the spine), not only local pains and muscular-tonic disorders occur, but also various reflex responses at a distance - in the area of integumentary tissues, innervationally connected with affected vertebral segments. But by no means in all cases there is a parallelism between the severity of radiological changes in the spine and clinical symptoms. Therefore, the radiographic signs of osteochondrosis cannot yet explain the cause of the development of muscle-fascial syndromes exclusively by vertebrogenic factors.

As a result of the influence of several etiological factors, muscle-tonic reactions develop in the form of hypertonicity of the affected muscle or muscle group, which is confirmed by an electromyographic study. Muscle spasm is one of the sources of pain. In addition, the violation of microcirculation in the muscle leads to local tissue ischemia, tissue edema, accumulation of kinins, histamine, heparin. All of these factors also cause pain. If muscle-fascial syndromes are observed for a long time, then fibrous degeneration of muscle tissue occurs.

The greatest difficulties in the differential diagnosis of musculo-fascial syndromes and pain of cardiac origin are found in the following types of syndromes: humeral-scapular periarthritis, scapular-rib syndrome, anterior chest wall syndrome, interscapular pain syndrome, pectoralis minor syndrome, scalene anterior muscle syndrome. The syndrome of the anterior chest wall is observed in patients after suffering myocardial infarction, as well as in non-coronary heart disease. It is assumed that after a myocardial infarction, the flow of pathological impulses from the heart spreads along the segments of the autonomic chain and leads to dystrophic changes in the corresponding formations. This syndrome in persons with a known healthy heart may be due to traumatic myositis.

More rare syndromes accompanied by pain in the anterior chest wall are: Titze's syndrome, xyphoidia, manubriosternal syndrome, scalenus syndrome.

Tietze's syndrome is characterized by sharp soreness at the junction of the sternum with the cartilage of the II-IV ribs, swelling of the costal-cartilaginous joints. It is observed mainly in middle-aged people. The etiology and pathogenesis are unclear. There is an assumption about aseptic inflammation of the costal cartilage.

Xyphoidia is manifested by sharp pain in the lower part of the sternum, aggravated by pressure on the xiphoid process, sometimes accompanied by nausea. The cause of the pain is unclear, perhaps there is a connection with the pathology of the gallbladder, duodenum, stomach.

With manubriosternal syndrome, acute pain is noted above the upper part of the sternum or somewhat lateral. The syndrome is observed in rheumatoid arthritis, but it occurs in isolation and then it becomes necessary to differentiate it from angina pectoris.

Scalenus syndrome - compression of the neurovascular bundle of the upper limb between the anterior and middle scalene muscle, as well as the normal I or additional rib. Pain in the anterior chest wall is combined with pain in the neck, shoulder girdle, shoulder joints, sometimes there is a wide zone of irradiation. At the same time, vegetative disorders are observed in the form of chills, pallor of the skin. Difficulty breathing, Raynaud's syndrome are noted.

Summarizing the above, it should be noted that the true frequency of pains of this origin is unknown, therefore, it is not possible to determine their share in the differential diagnosis of angina pectoris.

Differentiation is necessary in the initial period of the disease (when they first of all think about angina pectoris) or if the pain caused by the listed syndromes is not combined with other signs that make it possible to correctly recognize their origin. At the same time, pains of a similar origin can be combined with true coronary artery disease, and then the doctor must also understand the structure of this complex pain syndrome. The need for this is obvious, since the correct interpretation will affect both treatment and prognosis.

Chest pain caused by diseases of the abdominal organs and pathology of the diaphragm. Diseases of the abdominal organs are quite often accompanied by pain in the region of the heart in the form of a syndrome of typical angina pectoris or cardialgia. Pain in gastric ulcer and duodenal ulcer, chronic cholecystitis can sometimes radiate to the left half of the chest, which gives rise to diagnostic difficulties, especially if the diagnosis of the underlying disease has not yet been established. Such irradiation of pain is quite rare, but its possibility should be taken into account when interpreting pain in the region of the heart and behind the sternum. The occurrence of these pains is explained by reflex effects on the heart with lesions of internal organs, which occur as follows. In the internal organs, interorgan connections have been found, through which axon reflexes are carried out, and, finally, polyvalent receptors in the vessels and smooth muscles have been identified. In addition, it is known that, along with the main border sympathetic trunks, there are also paravertebral plexuses connecting both border trunks, as well as sympathetic collaterals, located parallel and on the sides of the main sympathetic trunk. In such conditions, afferent excitation, going from any organ along a reflex arc, can switch from centripetal to centrifugal paths and thus be transmitted to various organs and systems. At the same time, viscero-visceral reflexes are carried out not only by reflex arcs, which are closed at various levels of the central nervous system, but also through autonomic nerve nodes in the periphery.

As for the causes of reflex pain in the region of the heart, it is assumed that a long-term painful focus disrupts the primary afferent impulse from organs due to a change in the reactivity of the receptors located in them and in this way becomes a source of pathological afferentation. Pathologically altered impulses lead to the formation of dominant foci of irritation in the cortex and subcortical region, in particular in the hypothalamic region and in the reticular formation. Thus, the irradiation of these stimuli is accomplished with the help of central mechanisms. From here, pathological impulses are transmitted by efferent pathways through the underlying parts of the central nervous system and then along sympathetic fibers reach the vasomotor receptors of the heart.

Diaphragmatic hernias can also cause chest pain. The diaphragm is a richly innervated organ mainly due to the phrenic nerve. It runs along the front inner edge m. Scalenus anticus. In the mediastinum, it goes along with the superior vena cava, then, bypassing the mediastinal pleura, reaches the diaphragm, where it branches. Hernias of the esophageal opening of the diaphragm are more common. Symptoms of diaphragmatic hernias are varied: usually dysphagia and pain in the lower chest, belching and a feeling of fullness in the epigastrium. When a hernia is temporarily introduced into the chest cavity, there is a sharp pain that can be projected onto the lower left half of the chest and spreads to the interscapular region. Concomitant spasm of the diaphragm can cause pain in the left scapular region and in the left shoulder, reflected due to irritation of the phrenic nerve, suggesting "heart" pain. Given the paroxysmal nature of pain, its appearance in middle-aged and elderly people (mainly in men), a differential diagnosis with an attack of angina pectoris should be carried out.

Pain can also be caused by diaphragmatic pleurisy and, much less often, by subphrenic abscess.

In addition, when examining the chest, shingles can be detected, and palpation can reveal a fractured rib (local soreness, crepitus).

Thus, to determine the cause of chest pain and make the correct diagnosis, the general practitioner should conduct a thorough examination and questioning of the patient and take into account the possibility of the existence of all of the above conditions.

[1], [2], [3], [4], [5], [6]