What is the diastolic heart sound formed by? Heart sounds: concept, auscultation, what pathological ones indicate

There is evidence that already in utero the future person hears the sounds of the mother’s beating heart above him. How do they form during the beating of the heart? What mechanisms are involved in the formation of the sound effect during cardiac activity? These questions can be answered if you have a good understanding of how blood moves through the heart cavities and vessels.

1 “Pay off the first, the second!”

The first tone and the second heart sound are the same “knock-knock”, the main sounds that are best heard by the human ear. Experienced doctor In addition to the main ones, he is well versed in additional and inconsistent sounds. The first and second tone are constant heart sounds that, with their rhythmic beating, signal normal operation the main human “engine”. How are they formed? Again you will have to remember the structure of the heart and the movement of blood through it.

Blood enters right atrium, then into the ventricle and lungs, from the lungs the purified blood returns to the left parts of the heart. How does blood move through the valves? When blood flows from the right upper chamber of the heart into the ventricle, at the same second blood flows from the left atrium into the left ventricle, i.e. The atria normally contract synchronously. At the moment of contraction of the upper chambers, blood pours out of them into the ventricles, passing through the 2-leaf and 3-leaf valves. Then, after the lower chambers of the heart are filled with blood, the turn of contraction or ventricular systole occurs.

The first sound occurs precisely at the moment of ventricular systole; the sound is caused by the closure of the heart valves during muscle contraction. ventricular contraction, as well as the tension of the wall of the lower chambers of the heart, the vibrations of the most primary departments the main vessels leaving the heart, where blood is directly poured. The second tone occurs at the very beginning of relaxation or diastole, during this period the pressure in the ventricles drops sharply, blood from the aorta and pulmonary artery rushes back and the open semilunar valves quickly slam shut.

The sound of the slamming semilunar valves creates the second heart sound to a greater extent, and also plays a role in the sound effect of vibration of the walls of blood vessels. How to distinguish the first heart sound from the second heart sound? If we graphically depict the dependence of sound volume on time, we will be able to observe the following picture: between the first tone that appears and the second there is a very short period of time - systole, a long interval between the second tone and the first - diastole. After a long pause, the first tone always comes!

2 More about tones

In addition to the main ones, there are additional tones: III tone, IV, SCHOMK, and others. Additional sound phenomena occur when the operation of the valves and chambers of the heart is somewhat out of synchronization - their closure and contraction do not occur simultaneously. Additional sound phenomena may be within physiological norm, but more often indicate some pathological changes and conditions. The third may occur in an already damaged myocardium that is unable to relax well; it is heard immediately after the second.

If the doctor detects a third or fourth heart sound, then the rhythm of the contracting heart is called a “gallop” due to the similarity of its beat to the running of a horse. Sometimes III and IV (occurs before the first) can be physiological, they are very quiet, and occur in children and young people without cardiac pathology. But much more often the heart “gallops” with such problems as myocarditis, heart failure, heart attacks, narrowing of the valves and heart vessels.

SCHOMK - click of an opening mitral valve — characteristic feature narrowing or stenosis of the 2-leaf valve. U healthy person The valve flaps open inaudibly, but if there is a narrowing, the blood hits the flaps with greater force in order to squeeze further - a sound phenomenon occurs - a click. It can be heard well at the apex of the heart. When there is a heart attack, the heart “sings in the rhythm of a quail,” as cardiologists have dubbed this sound combination.

3 Louder is not better

Heart sounds have a certain volume, usually the first one is heard louder than the second. But there are situations when heart sounds are heard louder than the sound familiar to the doctor’s ear. The reasons for the increase can be either physiological, not related to the disease, or pathological. Less filling, more cardiopalmus promotes loudness, so detrained people have louder tones, while athletes, on the contrary, have quieter tones. When are heart sounds loud for physiological reasons?

1. Childhood. Thin rib cage child, rapid heartbeat gives tones good conductivity, volume and clarity;
2. Thin build;
3. Emotional excitement.

Pathological loudness can be caused by diseases such as:

• tumor processes in the mediastinum: with tumors, the heart seems to move closer to the chest, which is why sounds are heard louder;
• pneumothorax: high content air promotes better implementation sounds, like shrinking of part of the lung;
• vegetative-vascular dystonia;
• increased effect on the heart muscle during thyrotoxicosis, anemia.

An increase in only the first tone can be observed with cardiac arrhythmias, myocarditis, an increase in the size of the heart chambers, and a narrowing of the 2-leaf valve. An intensification or aortic accent of the II tone is heard when the vessels are damaged by atherosclerosis, as well as a consistently high blood pressure. The accent of the second pulmonary tone is characteristic of the pathology of the small circle: cor pulmonale, hypertension pulmonary vessels.

4 Quieter than usual

Decreased heart sounds in people with healthy heart may be due to developed muscles or a layer of adipose tissue. According to the laws of physics, overdeveloped muscles or fat muffle the sound phenomena of the beating heart. But quiet heart sounds should alert the doctor, because they can be direct evidence of such pathologies:

• heart attack,
• heart failure,
• myocarditis,
• dystrophy of the heart muscle,
• hydrothorax, pericarditis,
• pulmonary emphysema.

A weakened first tone will indicate to the doctor possible valve insufficiency, narrowing of the main “vessel of life” - the aorta or pulmonary trunk, or enlargement of the heart. A quiet second can signal a decrease in pulmonary pressure, valve insufficiency, and low blood pressure.

It should be remembered that if changes in tones are detected regarding their volume or formation, you should immediately make a visit to a cardiologist, perform echocardiography of the heart with Doppler, and also do a cardiogram. Even if your heart has never “been acting up” before, it is better to play it safe and get examined.

5 Sound by author

Some pathological tones have personal names. This emphasizes their uniqueness and connection with a specific disease, and also shows how much effort it took the doctor to identify, compose, diagnose, and confirm the presence of a sound phenomenon with a specific disease. So, one of these signature tones is the Traube double tone.

It is found in patients with insufficiency of the largest vessel, the aorta. Due to pathology of the aortic valves, blood returns to the left lower chamber of the heart, when it should relax and rest - in diastole, reverse blood flow or regurgitation occurs. This sound is heard when pressing with a stethoscope on a large (usually femoral) artery as a loud, double sound.

6 How to hear heart sounds?

This is what the doctor does. At the beginning of the 19th century, thanks to the intelligence and resourcefulness of R. Laeneck, the stethophonendoscope was invented. Before its invention, heart sounds were listened directly to the ear, pressed against the patient's body. When the famous scientist was invited to examine an obese lady, Laeneck rolled a tube out of paper and placed one end of it to the ear and the other to the woman’s chest. Having discovered that sound conductivity had increased significantly, Laeneck suggested that if this method examinations will be improved, it will be possible to listen to the heart and lungs. And he was right!

Before today Auscultation is the most important diagnostic method that every doctor in any country must know. The stethoscope is an extension of the doctor. This is a device that is capable of short time help the doctor determine the diagnosis, it is especially important when to use others diagnostic methods there is no possibility, in emergency cases or far from civilization.

WITH early childhood Everyone is familiar with the actions of a doctor when examining a patient, when using a phonendoscope to listen to the heart rhythm. The doctor listens especially carefully to heart sounds, especially fearing complications after infectious diseases, as well as when complaining of pain in this area.

What it is

Heart sounds are sound waves a certain frequency that occurs when the muscles and valves of the heart contract. A clear sound can be heard even when the ear is applied to the sternum. If rhythm disturbances are suspected, a phonendoscope is used for this and listened to at points located next to the heart valves.

During normal heart function, the duration of the cycle at rest is about 9/10 of a second, and consists of two stages - the contraction phase (systole) and the rest phase (diastole).

During the relaxation stage, the pressure in the chamber changes less than in the vessels. Liquid under slight pressure is thrown first into the atria and then into the ventricles. At the moment the latter are filled by 75%, the atria contract and force the remaining volume of fluid into the ventricles. At this time they talk about atrial systole. At the same time, the pressure in the ventricles increases, the valves slam shut and the areas of the atria and ventricles are isolated.

Blood presses on the muscles of the ventricles, stretching them, which causes a powerful contraction. This moment is called ventricular systole. After a split second, the pressure increases so much that the valves open and blood flows into the vascular bed, completely emptying the ventricles, in which a period of relaxation begins. At the same time, the pressure in the aorta is so high that the valves close and do not release blood.

The duration of diastole is longer than systole, so there is enough time for the heart muscle to rest.

The human hearing aid is very sensitive and picks up the most subtle sounds. This property helps doctors determine by the pitch of the sound how serious the disturbances in the heart are. Sounds occur due to the work of the myocardium, valve movements, and blood flow. Heart sounds normally sound sequential and rhythmic.

There are four main heart sounds:

1. occurs when a muscle contracts. It is created by vibration of the tense myocardium, noise from the operation of the valves. It is heard in the area of ​​the apex of the heart, near the 4th left intercostal space, and occurs synchronously with the pulsation of the carotid artery.
2. occurs almost immediately after the first. It is created due to the slamming of valve flaps. It is more deaf than the first and can be heard on both sides in the second hypochondrium. The pause after the second sound is longer and coincides with diastole.
3. optional tone, normally its absence is allowed. It is created by vibration of the walls of the ventricles at the moment when there is additional blood flow. To determine this tone you need sufficient listening experience and absolute silence. You can hear it well in children and adults with thin chest wall. U fat people harder to hear.
4. another optional heart sound, the absence of which is not considered a violation. Occurs when the ventricles fill with blood during atrial systole. Perfectly heard in people of thin build and children.

Pathology

Disturbances in sounds that occur during the work of the heart muscle can be caused by for various reasons, grouped into two main ones:

• Physiological, when changes are associated with certain characteristics of the patient’s health. For example, body fat in the listening area, the sound deteriorates, so heart sounds are muffled.
• Pathological when changes affect various elements of the cardiac system. For example, increased density The valve of the atrioventricular orifice adds a click to the first tone and the sound is louder than usual.

Pathologies arising at work of cardio-vascular system, are initially diagnosed by auscultation by a doctor during examination of the patient. The nature of the sounds is used to judge a particular violation. Afterwards, the doctor must record a description of the heart sounds in the patient’s chart.

Heart sounds that have lost the clarity of their rhythm are considered muffled. When dull tones weaken in the area of ​​all auscultation points, it leads to the assumption of the following pathological conditions:

• serious myocardial damage - extensive, inflammation of the heart muscle, proliferation of connective scar tissue;
• disorders not related to cardiac pathologies, for example, emphysema, pneumothorax;
• exudative.

If only one tone is weak at any location, the listening position is called more accurately pathological processes leading to this:

• voiceless first tone, heard at the apex of the heart indicates inflammation of the heart muscle, its sclerosis, partial destruction;
• dull second tone in the area of ​​the second intercostal space on the right speaks of insufficiency aortic valve or narrowing of the aortic mouth;
• dull second tone in the area of ​​the second intercostal space on the left indicates pulmonary valve insufficiency.

There are such changes in the tone of the heart that experts give them unique names. For example, “quail rhythm” - the first clapping tone is replaced by the second normal one, and then the echo of the first tone is added. Severe myocardial diseases are expressed in a three-member or four-member “gallop rhythm,” that is, blood fills the ventricles, stretching the walls, and vibration vibrations create additional sounds.

Simultaneous changes in all tones at different points are often heard in children due to the structure of their chest and the close location of the heart to it. The same can be observed in some adults of the asthenic type.

Typical disturbances can be heard:

• high first sound at the top of the heart appears when the left atrioventricular opening is narrow, as well as when;
• high second tone in the second intercostal space on the left indicates increasing pressure in the pulmonary circulation, which causes strong flapping of the valve leaflets;
• high second tone in the second intercostal space on the right shows in the aorta.

Interruptions in heart rate indicate pathological conditions systems as a whole. Not all electrical signals travel equally through the thickness of the myocardium, so the intervals between heartbeats are of different durations. When the atria and ventricles work uncoordinated, a “cannon tone” is heard - the simultaneous contraction of the four chambers of the heart.

In some cases, auscultation of the heart shows a separation of the tone, that is, the replacement of a long sound with a pair of short ones. This is due to a violation of the coordination of the muscles and valves of the heart.

The separation of the 1st heart sound occurs for the following reasons:

• closure of the tricuspid and mitral valves occurs in a temporary gap;
• contraction of the atria and ventricles occurs in different time and leads to disruption of the electrical conductivity of the heart muscle.
• The separation of the 2nd heart sound occurs due to the difference in the time of slamming of the valve leaflets.

This condition indicates the following pathologies:

• excessive increase in pressure in the pulmonary circulation;
• proliferation of left ventricular tissue with mitral valve stenosis.

With ischemia, the tone changes depending on the stage of the disease. The onset of the disease is poorly expressed in sound disturbances. During the periods between attacks, no deviations from the norm are observed. The attack is accompanied by a frequent rhythm, indicating that the disease is progressing, and heart sounds in children and adults change.

Medical professionals note that changes in heart sounds do not always indicate cardiovascular disorders. It happens that the causes are a number of diseases of other organ systems. Muffled tones and the presence of additional tones indicate diseases such as endocrine diseases, diphtheria. An increase in body temperature is often expressed in a disturbance in heart tone.

A competent doctor always tries to collect a complete medical history when diagnosing a disease. In addition to listening to heart sounds, he interviews the patient, carefully reviews his chart, and prescribes additional examinations according to the expected diagnosis.

Heart sounds- a sound manifestation of the mechanical activity of the heart, defined by auscultation as alternating short (percussive) sounds that are in a certain connection with the phases of systole and diastole of the heart. T.s. are formed in connection with the movements of the heart valves, chords, cardiac muscle and vascular wall, generating sound vibrations. The audible volume of tones is determined by the amplitude and frequency of these vibrations (see. Auscultation ). Graphic registration of T.s. using phonocardiography showed that, in its physical essence, T. s. are noise, and their perception as tones is due to the short duration and rapid attenuation of aperiodic oscillations.

Most researchers distinguish 4 normal (physiological) T.s., of which I and II tones are always heard, and III and IV are not always determined, more often graphically than by auscultation ( rice. ).

The first sound is heard as a fairly intense sound over the entire surface of the heart. It is maximally expressed in the region of the apex of the heart and in the projection of the mitral valve. The main fluctuations of the first tone are associated with the closure of the atrioventricular valves; participate in its formation and movements of other structures of the heart. On FCG, in the composition of the first tone, initial low-amplitude low-frequency oscillations associated with contraction of the ventricular muscles are distinguished; main, or central, segment of the first tone, consisting of vibrations of large amplitude and more high frequency(arising due to the closure of the mitral and tricuspid valves); the final part is low-amplitude oscillations associated with the opening and oscillation of the walls of the semilunar valves of the aorta and pulmonary trunk. The total duration of the first tone ranges from 0.7 to 0.25 With. At the apex of the heart, the amplitude of the first tone is 1 1/2 -2 times greater than the amplitude of the second tone. Weakening of the first tone may be associated with a decrease in the contractile function of the heart muscle during myocardial infarction, e, but it is especially pronounced in case of mitral valve insufficiency (the tone may practically not be heard, being replaced by systolic murmur). The flapping nature of the first tone (an increase in both the amplitude and frequency of oscillations) is most often determined with mitral e, when it is caused by compaction of the mitral valve leaflets and shortening of their free edge while maintaining mobility. A very loud (“cannonball”) I tone occurs with complete atrioventricular block (see. Heart block ) at the time of coincidence of systole, regardless of the contraction of the atria and ventricles of the heart.

The second sound is also heard over the entire region of the heart, maximally at the base of the heart: in the second intercostal space to the right and left of the sternum, where its intensity is greater than the first tone. The origin of the second sound is mainly associated with the closure of the aortic valves and pulmonary trunk. It also includes low-amplitude, low-frequency oscillations resulting from the opening of the mitral and tricuspid valves.

Ill tone - low frequency - is perceived during auscultation as a weak, dull sound. On FCG it is determined on the low-frequency channel, more often in children and athletes. In most cases, it is recorded at the apex of the heart, and its origin is associated with vibrations of the muscular wall of the ventricles due to their stretching at the time of rapid diastolic filling. Phonocardiographically, in some cases, left and right ventricular III sounds are distinguished. The interval between II and left ventricular tone is 0.12-15 With. The so-called opening tone of the mitral valve is distinguished from the third tone - a pathognomonic sign of mitral a. The presence of a second tone creates an auscultatory picture of the “quail rhythm”. Pathological III tone appears when heart failure and determines the proto- or mesodiastolic gallop rhythm (see. Gallop rhythm ). Ill tone is best heard with the stethoscope head of a stethoscope or by direct auscultation of the heart with the ear tightly attached to the chest wall.

IV tone - atrial - is associated with contraction of the atria. When recording synchronously with an ECG, it is recorded at the end of the P wave. This is a weak, rarely heard tone, recorded on the low-frequency channel of the phonocardiograph mainly in children and athletes. A pathologically enhanced IV tone causes a presystolic gallop rhythm during auscultation.

Heart sounds are waves of sound that occur when all the heart valves work and the myocardial muscle contracts. These heart sounds can be heard with a phonendoscope, and they can also be heard when you put your ear to your chest.

When listening specialized specialist, the doctor applies the head (membrane) of the phonendoscope instrument to those places where the heart muscle is located closest to the sternum.

Cardiac cycle

Each element of the heart organ works harmoniously and with a certain sequence. Only such work can guarantee normal blood flow in vascular system.

At the moment when the heart is in diastole, the blood pressure in the heart chambers is lower than in the aorta. Blood flows first into the atria and then into the ventricles.

When, during diastole, the ventricle is filled with biological fluid to three-quarters of its volume, the atrium contracts, during which the chamber is filled with the remaining volume of blood.

This action in medicine is called atrial systole.

When the ventricles are full, then the valve that separates the ventricles from the atria closes.

The volume of biological fluid stretches the walls of the ventricular chambers, and the walls of the chamber contract quickly and sharply - this action is called systole of the left-sided ventricle and the right-sided one.

When the blood pressure in the ventricles becomes higher than in the blood flow system, then the aortic valve opens and blood under pressure passes into the aorta.

The ventricles become empty and enter diastole. When all the blood has entered the aorta, the semilunar valves close and blood does not flow back into the ventricle.

Diastole lasts 2 times longer than systole, so this time is enough for the myocardium to rest.

The principle of tone formation

All movements in the work of the heart muscle, heart valves, and blood flow when injected into the aorta create sounds.

There are 4 tones in the heart organ:

• № 1 - sound from contraction of the heart muscle;
• № 2 - sound from valve operation;
• № 3 - during ventricular diastole (this tone may not be present, but according to the norm it is allowed);
• № 4 - when the atrium contracts at the moment of systole (this tone may also not be audible).

Tone No. 1 consists of:

• Trembling of the heart muscles;
• The sound of the slamming of the walls of the valve between the atrium and the ventricle;
• Trembling of the walls of the aorta as blood flows into it.

According to the standard indicator, this is the loudest among all audible tones of the cardiac organ.

The second manifests itself after a short period of time after the first.

This happens due to:

• Actuation of the aortic valve valve;
• Triggering of the pulmonary valve walls.

Tone No. 2. It is not as sonorous as the first and is heard between the second ribs on the left side of the heart area, and can also be heard on the right. The pause in sounds after the second is longer, because the beat occurs at the time of heart diastole.

Tone No. 3. This tone is not one of the required beats for the cardiac cycle. But according to the norm, this third tone is allowed, or may be absent.

The third occurs as a result when, during diastole, the walls of the left-sided ventricle shudder while it is filled with biological fluid.

In order to hear it during auscultation, you must have great experience in listening. Not instrumental method, this tone can only be heard in a quiet room, and also in children, because the heart and chest are located close.

Tone No. 4. Just like the third is not mandatory in cardiac cycle. If this tone is absent, this is not a myocardial pathology.

Upon auscultation, it can only be heard in children and the younger generation of people with a thin chest.

The reason for the 4th tone is the sound that occurs during the systolic state of the atrium, at the moment when the left and right ventricles are filled with biological fluid.

During normal functioning of the cardiac organ, rhythmicity occurs after the same time intervals. Normally, a healthy organ has 60 beats in one minute, the time interval between the first and second is 0.30 seconds.

The time interval from the second to the first is 0.60 seconds. Each tone is clearly audible, they are loud and clear. The first one sounds low and is long.

Start given first tone begins after a pause. The second sounds higher in sound and begins after a short pause, and it is slightly shorter in length than the first.

The third and fourth tones are heard after the second oh, at the moment when diastole of the cardiac cycle occurs.

How are heart sounds heard?

For instrumental listening to heart sounds, as well as listening to the work of the bronchi, lungs and when measuring blood pressure using the Korotkov method, a phonendoscope (stethoscope) is used.

To listen to heart sounds, a cardiological type of phonendoscope is used - with increased sound capture by the membrane.

The order of listening to heart sounds during auscultation

During auscultation, the valves of the heart organ are heard, their function and rhythm.

Localization of tones when listening to valves:

• Bicuspid valve at the top of the heart organ;
• Listening to the aortic valve under the second rib with right side cardiac localization;
• Listening to the operation of the pulmonary artery valve;
• Recognition of the tone of work tricuspid valve.

Listening to cardiac impulses and their tone during auscultation takes place in a certain sequence:

• Locality of apical systole;
• Second intercostal space on the right side of the chest edge;
• Second intercostal space on the left side of the chest;
• Bottom of the sternum (locality of the xiphoid process);
• Erb-Botkin localization point.

This sequence when listening to heart sounds is due to damage to the valves of the cardiac organ and will allow you to correctly listen to the tone of each valve and identify the performance of the myocardium. Coherence in work is immediately reflected in the tones and their rhythm.

Changes in heart sounds

Heart sounds are waves of sound, so any deviation or disturbance indicates a pathology of one of the structures of the cardiac organ.

In medicine, the reasons for deviations from standard indicators sound of tones:

• Physiological changes- these are reasons that are associated with the physiology of the person whose heart is being listened to. The sounds will not be clear when listening to a person who is obese. Excess fat on the chest prevents good hearing;
• Pathological change in knocking- these are deviations in the functioning of the cardiac structures or damage to parts of the cardiac organ, as well as the arteries extending from it. A loud knock occurs because the walls of the damper thicken, become less elastic and make a loud sound when closing. The first knock produces a click.

Muffled tones

Muffled knocks are sounds that are not clear and hard to hear.

Faint sounds may be a sign of pathology in the cardiac organ:

• Diffuse destruction of myocardial tissue - myocarditis;
• Myocardial infarction attack;
• Cardiosclerosis disease;
• Pericarditis disease;
• Pathology in the lungs - emphysema.

If the first knock or the second weakens, and audibility during auscultation in different sides not the same.

This then expresses the following pathology:

• If there is a muffled sound from above the cardiac organ, then this indicates that pathology is developing - myocarditis, myocardial sclerosis, as well as its partial destruction and valve insufficiency;
• A dull sound in the 2nd hypochondrium indicates that there is a malfunction of the aortic valve, or stenosis of the aortic walls, in which the compacted walls do not have the ability to stretch elastically;

Some changes in the tonality of heart sounds have specific characteristic accents and have a specific name.

With mitral valve stenosis, a sound occurs - called the quail rhythm, where the first knock is heard like a clap and the second immediately occurs.

After the second, an echo of an additional tone occurs, which is characteristic of this pathology.

If myocardial pathology has progressed to severe degree the course of the disease, then a three-beat or four-beat sound occurs - the gallop rhythm. With this pathology biological fluid stretches the walls of the ventricular chambers, which leads to additional sounds in the rhythm.

Gallop rhythm

• The combined combination of the first, second and third is a protodiastolic rhythm;
• The simultaneous combination of the first tone, the second and the fourth is a presystolic rhythm;
• The quadruple rhythm is the combination of all four tones;
• The total rhythm during tachycardia is the audibility of four tones, but at the moment of diastole the third and 4th sounds merge into one sound.

Enhanced tone sounds

Increased heart sounds are heard in children and skinny people, because their chest is thin, which allows the phonendoscope to hear better, since the membrane is located next to the heart organ.

If pathology is observed, then this is expressed in the brightness and volume of tones and in specific localization:

• The loud and ringing first sound in the upper part of the heart organ indicates a pathology of the atrioventricular left-sided valve, namely narrowing of the walls of the valve. This sound is expressed during tachycardia, sclerosis of the mitral valve, because the valve flaps have become thickened and lost their elasticity;
• The second sound in this place means o high level blood pressure, which is reflected in the pulmonary circulation. This pathology leads to the fact that the valve flaps on the pulmonary artery quickly slam shut because they have lost elasticity;
• A loud and ringing sound in the second hypochondrium indicates the pathology of high aortic pressure, stenosis of the aortic walls, as well as the progression of atherosclerosis.

Arrhythmia of heart sounds

Tones that do not have rhythm (arrhythmia) indicate that there is a clear deviation in the blood conducting system of the cardiac organ.

Pulsation occurs at different time intervals because not every contraction in the heart passes through the entire thickness of the myocardium.

The disease atrioventricular block manifests itself in the uncoordinated work of the atria and the left and right ventricles, which produces a tone - a cannon rhythm.

This sound occurs during simultaneous systole of all cardiac chambers.

Does not have a coherent rhythm and split tones. This happens when one tone is divided into 2 short ones. This pathology is due to the fact that the work of the heart valves is not harmonious with the myocardium itself.

Splitting of one tone occurs due to:

• The mitral valve and tricuspid valve do not close at the same time. This occurs with the disease tricuspid stenosis of the tricuspid valve, or with stenosis of the walls of the mitral valve;
• The conduction of electrical impulses to the ventricles and atria by the heart muscle is impaired. Insufficient conductivity causes arrhythmia in the functioning of the ventricular and atrial chambers.

The arrhythmia and demarcation of the second number of knocks, when the valves slam shut at different moments, indicate abnormalities in the heart.

In the coronary vascular system:

• High arterial pressure in a small circle of blood flow, provokes oxygen starvation;
• Pronounced arterial hypertension(hypertension);
• Hypertrophy of the walls of the left ventricle, with pathology of the mitral valve, as well as stenosis of this valve. The systole of the mitral valve leaflets closes later, which leads to disturbances in the aortic valve.

In case of coronary heart disease, the change in tone depends on the stage of the disease and on the damage to the myocardium and the condition of the valves.

On primary stage development of the disease, the tones are not very deviated from the norm, and the signs of ischemia are weakly expressed.

Angina pectoris manifests itself in attacks. At the time of an attack of angina pectoris, with ischemic heart disease ( coronary disease heart), the heartbeat becomes a little muffled, the rhythmicity in the tones disappears, and a gallop rhythm appears.

With further progression of angina, dysfunction of the heart muscle and valves between the myocardial chambers does not occur at the time of an angina attack, but occurs on an ongoing basis.

Conclusion

A change in the rhythm of the heartbeat is not always a sign of heart disease or diseases of the blood vessel system, and irregularity can also manifest itself in thyrotoxicosis, infectious diseases- diphtheria.

Many pathologies and viral diseases influence the rhythm of cardiac impulses, as well as the tone of these impulses.

Additional heart sounds also appear not only in heart disease. Therefore, to establish correct diagnosis must be passed instrumental study myocardium, vascular system, and also using a phonendoscope to listen to all the sounds of the cardiac organ.

Heart sounds are waves of sound that occur when all the heart valves work and the myocardial muscle contracts. These heart sounds can be heard with a phonendoscope, and they can also be heard when you put your ear to your chest.

When listening to a specialized specialist, the doctor applies the head (membrane) of the phonendoscope instrument to those places where the heart muscle is located closest to the sternum.

Cardiac cycle

Each element of the heart organ works harmoniously and with a certain sequence. Only such work can guarantee normal blood flow in the vascular system.

At the moment when the heart is in diastole, the blood pressure in the heart chambers is lower than in the aorta. Blood flows first into the atria and then into the ventricles.

When, during diastole, the ventricle is filled with biological fluid to three-quarters of its volume, the atrium contracts, during which the chamber is filled with the remaining volume of blood.

This action in medicine is called atrial systole.

When the ventricles are full, then the valve that separates the ventricles from the atria closes.

The volume of biological fluid stretches the walls of the ventricular chambers, and the walls of the chamber contract quickly and sharply - this action is called systole of the left-sided ventricle and the right-sided one.

When the blood pressure in the ventricles becomes higher than in the blood flow system, then the aortic valve opens and blood under pressure passes into the aorta.

The ventricles become empty and enter diastole. When all the blood has entered the aorta, the semilunar valves close and blood does not flow back into the ventricle.

Diastole lasts 2 times longer than systole, so this time is enough for the myocardium to rest.

The principle of tone formation

All movements in the work of the heart muscle, heart valves, and blood flow when injected into the aorta create sounds.

There are 4 tones in the heart organ:

• № 1 - sound from contraction of the heart muscle;
• № 2 - sound from valve operation;
• № 3 - during ventricular diastole (this tone may not be present, but according to the norm it is allowed);
• № 4 - when the atrium contracts at the moment of systole (this tone may also not be audible).

Tone No. 1 consists of:

• Trembling of the heart muscles;
• The sound of the slamming of the walls of the valve between the atrium and the ventricle;
• Trembling of the walls of the aorta as blood flows into it.

According to the standard indicator, this is the loudest among all audible tones of the cardiac organ.

The second manifests itself after a short period of time after the first.

This happens due to:

• Actuation of the aortic valve valve;
• Triggering of the pulmonary valve walls.

Tone No. 2. It is not as sonorous as the first and is heard between the second ribs on the left side of the heart area, and can also be heard on the right. The pause in sounds after the second is longer, because the beat occurs at the time of heart diastole.

Tone No. 3. This tone is not one of the required beats for the cardiac cycle. But according to the norm, this third tone is allowed, or may be absent.

The third occurs as a result when, during diastole, the walls of the left-sided ventricle shudder while it is filled with biological fluid.

In order to hear it during auscultation, you must have extensive listening experience. Not by an instrumental method, this tone can only be heard in a quiet room, and also in children, because the heart and chest are located close.

Tone No. 4. Just like the third is not mandatory in the cardiac cycle. If this tone is absent, this is not a myocardial pathology.

Upon auscultation, it can only be heard in children and the younger generation of people with a thin chest.

The reason for the 4th tone is the sound that occurs during the systolic state of the atrium, at the moment when the left and right ventricles are filled with biological fluid.

During normal functioning of the cardiac organ, rhythmicity occurs after the same time intervals. Normally, a healthy organ has 60 beats in one minute, the time interval between the first and second is 0.30 seconds.

The time interval from the second to the first is 0.60 seconds. Each tone is clearly audible, they are loud and clear. The first one sounds low and is long.

The onset of this first tone begins after a pause. The second sounds higher in sound and begins after a short pause, and it is slightly shorter in length than the first.

The third and fourth tones are heard after the second oh, at the moment when diastole of the cardiac cycle occurs.

How are heart sounds heard?

For instrumental listening to heart sounds, as well as listening to the work of the bronchi, lungs and when measuring blood pressure using the Korotkov method, a phonendoscope (stethoscope) is used.

To listen to heart sounds, a cardiological type of phonendoscope is used - with increased sound capture by the membrane.

The order of listening to heart sounds during auscultation

During auscultation, the valves of the heart organ are heard, their function and rhythm.

Localization of tones when listening to valves:

• Bicuspid valve at the top of the heart organ;
• Listening to the aortic valve under the second rib on the right side of the heart;
• Listening to the operation of the pulmonary artery valve;
• Recognition of the tonality of the tricuspid valve.

Listening to cardiac impulses and their tone during auscultation takes place in a certain sequence:

• Locality of apical systole;
• Second intercostal space on the right side of the chest edge;
• Second intercostal space on the left side of the chest;
• Bottom of the sternum (locality of the xiphoid process);
• Erb-Botkin localization point.

This sequence when listening to heart sounds is due to damage to the valves of the cardiac organ and will allow you to correctly listen to the tone of each valve and identify the performance of the myocardium. Coherence in work is immediately reflected in the tones and their rhythm.

Changes in heart sounds

Heart sounds are waves of sound, so any deviation or disturbance indicates a pathology of one of the structures of the cardiac organ.

In medicine, the reasons for deviations from the normative indicators of the sound of tones are identified:

• Physiological changes- these are reasons that are associated with the physiology of the person whose heart is being listened to. The sounds will not be clear when listening to a person who is obese. Excess fat on the chest prevents good hearing;
• Pathological change in knocking- these are deviations in the functioning of the cardiac structures or damage to parts of the cardiac organ, as well as the arteries extending from it. A loud knock occurs because the walls of the damper thicken, become less elastic and make a loud sound when closing. The first knock produces a click.

Muffled tones

Muffled knocks are sounds that are not clear and hard to hear.

Faint sounds may be a sign of pathology in the heart organ:

• Diffuse destruction of myocardial tissue - myocarditis;
• Myocardial infarction attack;
• Cardiosclerosis disease;
• Pericarditis disease;
• Pathology in the lungs - emphysema.

If the first knock or the second weakens, and audibility during auscultation in different directions is not the same.

This then expresses the following pathology:

• If there is a muffled sound from above the cardiac organ, then this indicates that pathology is developing - myocarditis, myocardial sclerosis, as well as its partial destruction and valve insufficiency;
• A dull sound in the 2nd hypochondrium indicates that there is a malfunction of the aortic valve, or stenosis of the aortic walls, in which the compacted walls do not have the ability to stretch elastically;

Some changes in the tonality of heart sounds have specific characteristic accents and have a specific name.

With mitral valve stenosis, a sound occurs - called the quail rhythm, where the first knock is heard like a clap and the second immediately occurs.

After the second, an echo of an additional tone occurs, which is characteristic of this pathology.

If the myocardial pathology has progressed to a severe degree of the disease, then a three-beat or four-beat sound occurs - a gallop rhythm. With this pathology, biological fluid stretches the walls of the ventricular chambers, which leads to additional sounds in the rhythm.

Gallop rhythm

• The combined combination of the first, second and third is a protodiastolic rhythm;
• The simultaneous combination of the first tone, the second and the fourth is a presystolic rhythm;
• The quadruple rhythm is the combination of all four tones;
• The total rhythm during tachycardia is the audibility of four tones, but at the moment of diastole the third and 4th sounds merge into one sound.

Enhanced tone sounds

Increased heart sounds are heard in children and thin people because their chest is thin, which allows the phonendoscope to hear better, since the membrane is located next to the heart organ.

If pathology is observed, then this is expressed in the brightness and volume of tones and in specific localization:

• The loud and ringing first sound in the upper part of the heart organ indicates a pathology of the atrioventricular left-sided valve, namely narrowing of the walls of the valve. This sound is expressed during tachycardia, sclerosis of the mitral valve, because the valve flaps have become thickened and lost their elasticity;
• The second sound in this place means a high level of blood pressure, which is reflected in the small blood circle. This pathology leads to the fact that the valve flaps on the pulmonary artery quickly slam shut because they have lost elasticity;
• A loud and ringing sound in the second hypochondrium indicates the pathology of high aortic pressure, stenosis of the aortic walls, as well as the progression of atherosclerosis.

Arrhythmia of heart sounds

Tones that do not have rhythm (arrhythmia) indicate that there is a clear deviation in the blood conducting system of the cardiac organ.

Pulsation occurs at different time intervals because not every contraction in the heart passes through the entire thickness of the myocardium.

The disease atrioventricular block manifests itself in the uncoordinated work of the atria and the left and right ventricles, which produces a tone - a cannon rhythm.

This sound occurs during simultaneous systole of all cardiac chambers.

Does not have a coherent rhythm and split tones. This happens when one tone is divided into 2 short ones. This pathology is due to the fact that the work of the heart valves is not harmonious with the myocardium itself.

Splitting of one tone occurs due to:

• The mitral valve and tricuspid valve do not close at the same time. This occurs with the disease tricuspid stenosis of the tricuspid valve, or with stenosis of the walls of the mitral valve;
• The conduction of electrical impulses to the ventricles and atria by the heart muscle is impaired. Insufficient conductivity causes arrhythmia in the functioning of the ventricular and atrial chambers.

The arrhythmia and demarcation of the second number of knocks, when the valves slam shut at different moments, indicate abnormalities in the heart.

In the coronary vascular system:

• High blood pressure in the pulmonary circulation provokes oxygen starvation;
• Severe arterial hypertension (hypertension);
• Hypertrophy of the walls of the left ventricle, with pathology of the mitral valve, as well as stenosis of this valve. The systole of the mitral valve leaflets closes later, which leads to disturbances in the aortic valve.

In case of coronary heart disease, the change in tone depends on the stage of the disease and on the damage to the myocardium and the condition of the valves.

At the primary stage of development of the disease, the tones are not very deviated from the norm, and the signs of ischemia are weakly expressed.

Angina pectoris manifests itself in attacks. At the time of an attack of angina pectoris, with ischemic heart disease (coronary heart disease), the heartbeat becomes slightly muffled, the rhythm in tones disappears, and a gallop rhythm appears.

With further progression of angina, dysfunction of the heart muscle and valves between the myocardial chambers does not occur at the time of an angina attack, but occurs on an ongoing basis.

Conclusion

A change in the rhythm of the heartbeat is not always a sign of heart disease or diseases of the blood vessel system, and irregularity can also manifest itself in thyrotoxicosis, infectious diseases - diphtheria.

Many pathologies and viral diseases affect the rhythm of cardiac impulses, as well as the tone of these impulses.

Additional heart sounds also appear not only in heart disease. Therefore, to establish the correct diagnosis, it is necessary to undergo an instrumental examination of the myocardium, the vascular system, and also listen to all the sounds of the cardiac organ using a phonendoscope.