What are tones? Characteristics of tones and sequence of listening. Auscultation of the heart: heart tones What does sp tones mean muffled rhythm correct

Heart valve function set out in our articles in the section on human physiology, which emphasizes that the sounds heard by the ear arise when the valves slam. Conversely, when the valves open, no sounds are heard. In this article, we will first discuss the causes of sounds during the work of the heart in normal and pathological conditions. Then we will give an explanation of those hemodynamic shifts that occur due to dysfunction of the valves, as well as in congenital heart defects.

When listening healthy heart stethoscope commonly heard are sounds that can be described as "boo, thump, boo, thump". The combination of sounds "bu" characterizes the sound that occurs when the atrioventricular valves close at the very beginning of the ventricular systole, which is called the first heart sound. The combination of sounds "stupid" characterizes the sound that occurs when the semilunar valves of the aorta and pulmonary artery close at the very end of systole (at the beginning of diastole) of the ventricles, which is called the second heart sound.

Causes of the first and second heart sounds. The simplest explanation for the occurrence of heart sounds is the following: the leaflets of the valves "collapse", and there is a vibration or trembling of the valves. However, this effect is insignificant, because the blood between the valve flaps at the moment of their slamming smooths out their mechanical interaction and prevents the occurrence of loud sounds. The main reason for the appearance of sound is the vibration of tightly stretched valves immediately after their slamming, as well as the vibration of adjacent sections of the wall of the heart and large vessels located near the heart.

So, formation of the first tone can be described as follows: ventricular contraction initially causes blood to flow back into the atria to the location of the A-B valves (mitral and tricuspid). The valves slam shut and flex toward the atria until tension in the tendon filaments stops this movement. The elastic tension of the tendon filaments and valve cusps reflects the blood flow and directs it back towards the ventricles. This creates vibration of the wall of the ventricles, tightly closed valves, as well as vibration and turbulent eddies in the blood. The vibration propagates through the adjacent tissues to the chest wall, where with the help of a stethoscope these vibrations can be heard as the first heart sound.

Second heart sound occurs as a result of the slamming of the semilunar valves at the end of ventricular systole. When the semilunar valves close, they bend under the pressure of blood towards the ventricles and stretch, and then, due to elastic recoil, they sharply shift back towards the arteries. This causes a brief turbulent movement of blood between the arterial wall and the semilunar valves, and between the valves and the ventricular wall. The resulting vibration then spreads along the arterial vessel through the surrounding tissues up to the chest wall, where you can listen to the second heart sound.

Height and duration of the first and second heart sounds. The duration of each of the heart sounds barely exceeds 0.10 seconds: the duration of the first is 0.14 seconds, and the second - 0.11 seconds. The duration of the second tone is shorter, because. semilunar valves have greater elastic tension than A-B valves; their vibration continues for a short period of time.

Frequency characteristics(or height) of heart sounds is shown in the figure. The spectrum of sound vibrations includes the lowest frequency sounds, barely exceeding the limit of audibility - about 40 vibrations per second (40 Hz), as well as sounds with a frequency of up to 500 Hz. Registration of heart sounds with the help of special electronic equipment showed that most of the sound vibrations have a frequency below the threshold of hearing: from 3-4 Hz to 20 Hz. For this reason, most of the sound vibrations that make up heart sounds are not audible through a stethoscope, but can only be recorded as a phonocardiogram.

Second heart sound normally consists of sound vibrations of a higher frequency than the first tone. The reasons for this are: (1) the greater elastic tension of the semilunar valves compared to the A-B valves; (2) a higher coefficient of elasticity in the walls of arterial vessels, which form sound vibrations of the second tone, than in the walls of the ventricles, which form sound vibrations of the first heart sound. These features are used by clinicians to distinguish between first and second heart sounds when listening.

Heart sounds- a sound manifestation of the mechanical activity of the heart, determined by auscultation as alternating short (percussive) sounds that are in a certain connection with the phases of the systole and diastole of the heart. T. s. are formed in connection with the movements of the valves of the heart, chords, heart muscle and vascular wall, generating sound vibrations. The auscultated loudness of tones is determined by the amplitude and frequency of these oscillations (see. Auscultation ). Graphic registration T. with. with the help of phonocardiography showed that, in terms of its physical nature, T. s. are noises, 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 during auscultation ( rice. ).

I tone 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 I tone are associated with the closure of the atrioventricular valves; participate in its formation and movements of other structures of the heart. On FCG, as part of tone I, initial low-amplitude low-frequency oscillations associated with contraction of the muscles of the ventricles are distinguished; the main, or central, segment of the I tone, consisting of oscillations of large amplitude and higher frequency (arising from the closure of the mitral and tricuspid valves); the final part - 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 I tone ranges from 0.7 to 0.25 With. At the apex of the heart, the amplitude of the I tone is 1 1/2 -2 times greater than the amplitude of the II tone. The weakening of the I tone may be associated with a decrease in the contractile function of the heart muscle during myocardial infarction, e, but it is especially pronounced with mitral valve insufficiency (the tone may practically not be heard, being replaced by a systolic murmur). The clapping character of the I tone (increase in both amplitude and frequency of oscillations) is most often determined with mitral e, when it is due to compaction of the mitral valve cusps and shortening of their free edge while maintaining mobility. Very loud ("cannon") I tone occurs with complete atrioventricular blockade (see. heart block ) at the time of coincidence in systole time, regardless of the contracting atria and ventricles of the heart.

II tone is also auscultated over the entire region of the heart, as much as possible - 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 II tone is mainly associated with the closure of the valves of the aorta 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 FKG it is determined on a 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 fluctuations in the muscular wall of the ventricles due to their stretching at the time of rapid diastolic filling. Phonocardiographically, in some cases, a left and right ventricular III tone is distinguished. The interval between II and left ventricular tone is 0.12-15 With. The so-called mitral valve opening tone is distinguished from the III tone - a pathognomonic sign of mitral a. The presence of the second tone creates an auscultatory picture of the “quail rhythm”. Pathological III tone appears when heart failure and causes proto- or mesodiastolic gallop rhythm (see. gallop rhythm ). Ill tone is better heard with a stethoscopic head of a stethophonendoscope or by direct auscultation of the heart with an ear tightly attached to the chest wall.

IV tone - atrial - is associated with atrial contraction. With synchronous recording 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. Pathologically enhanced IV tone causes a presystolic gallop rhythm during auscultation.

Heart sounds

a sound manifestation of the mechanical activity of the heart, determined by auscultation as alternating short (percussion) sounds, which 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 valves of the heart, chords, cardiac and vascular walls, generating sound vibrations. The listened loudness of tones is determined by the amplitude and frequency of these oscillations (see Auscultation) . Graphic registration T. with. with the help of phonocardiography showed that, in terms of its physical nature, T. s. are noises, and they are like tones due to the short duration and rapid damping 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 during auscultation ( rice. ).

I tone is heard as quite intense 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 I tone are associated with the closure of the atrioventricular valves; participate in its formation and movements of other structures of the heart. On FCG, as part of tone I, initial low-amplitude low-frequency oscillations associated with contraction of the muscles of the ventricles are distinguished; the main, or central, I tone, consisting of oscillations of large amplitude and higher frequency (arising from the closure of the mitral and tricuspid valves); the final part - 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 I tone ranges from 0.7 to 0.25 With. At the apex of the heart, the amplitude of the I tone is 1 1/2 -2 times greater than the amplitude of the II tone. The weakening of the I tone may be associated with a decrease in the contractile function of the heart muscle during myocardial infarction, myocarditis, but it is especially pronounced with mitral valve insufficiency (it may practically not be heard, being replaced by systolic murmur). Flapping I tone (increase in both amplitude and frequency of oscillations) is most often determined with mitral stenosis, when it is caused by compaction of the mitral valve cusps and shortening of their free edge while maintaining mobility. A very loud ("cannon") I tone occurs with complete atrioventricular block (see Heart block) at the time of coincidence in systole time, regardless of the contracting atria and ventricles of the heart.

II tone is also auscultated over the entire region of the heart, as much as possible - 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 II tone is mainly associated with the closure of the valves of the aorta and pulmonary trunk. It also includes low-amplitude low-frequency oscillations resulting from the opening of the mitral and tricuspid valves. On FCG, the first (aortic) and second (pulmonary) components are distinguished as part of the II tone. The amplitude of the first component is 1 1/2 -2 times greater than the amplitude of the second. The interval between them can reach 0.06 With which is perceived during auscultation as the second tone. It can be given with physiological asynchronism of the left and right halves of the heart, which is most common in children. An important characteristic of the physiological splitting of the II tone is its phases of respiration (non-fixed splitting). The basis of a pathological or fixed, splitting of the II tone with a change in the ratio of the aortic and pulmonary components can be an increase in the duration of the phase of expulsion of blood from the ventricles and a slowdown in intraventricular conduction. The volume of the II tone during its auscultation over the aorta and pulmonary trunk is approximately the same; if it prevails over any of these vessels, they speak of an accent of the II tone over this vessel. The weakening of the second tone is most often associated with the destruction of the aortic valve cusps in case of its insufficiency or with a sharp limitation of their mobility in severe aortic stenosis. Strengthening, as well as an accent of the II tone over the aorta, occurs with arterial hypertension in the systemic circulation (see Arterial hypertension) , above the pulmonary trunk - with hypertension of the pulmonary circulation (Hypertension of the pulmonary circulation) .

Ill tone - low-frequency - is perceived during auscultation as a weak, dull sound. On FKG it is determined on a 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 fluctuations in the muscular wall of the ventricles due to their stretching at the time of rapid diastolic filling. Phonocardiographically, in some cases, a left and right ventricular III tone is distinguished. The interval between II and left ventricular tone is 0.12-15 With. The so-called mitral valve opening tone is distinguished from the III tone - a sign of mitral stenosis. The presence of the second tone creates an auscultatory picture of the “quail rhythm”. III tone appears with heart failure (Heart failure) and causes proto- or mesodiastolic (see Gallop rhythm) . Ill tone is better heard with a stethoscopic head of a stethophonendoscope or by direct auscultation of the heart with an ear tightly attached to the chest wall.

IV tone - atrial - is associated with atrial contraction. With synchronous recording, c 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. Pathologically enhanced IV tone causes a presystolic gallop rhythm during auscultation. The fusion of III and IV pathological tones in tachycardia is defined as "summation gallop".

A number of additional systolic and diastolic tones (clicks) are determined with Pericarditis e , pleuropericardial adhesions , mitral valve prolapse.

Bibliography: Kassirsky G.I. with congenital and acquired heart defects, Tashkent 1972, bibliogr.; Solovyov V.V. and Kassirsky G.I. Atlas of clinical phonocardiography, M., 1983; Fitileva L. M. Clinical, M., 1968; Holldak K. and Wolf D. Atlas and guide to phonocardiography and related mechanocardiographic research methods, with German, M., 1964.

heart sounds; a - the initial component of the I tone, b - the central segment of the I tone; c - the final component of the I tone; A - aortic component of the II tone; P - pulmonary component of the II tone "\u003e

Schematic representation of synchronously recorded phonocardiograms (bottom) and electrocardiograms (top) are normal: I, II, III, IV - corresponding heart sounds; a - the initial component of the I tone, b - the central segment of the I tone; c - the final component of the I tone; A - aortic component of the II tone; P - pulmonary component of the II tone.

1. Small medical encyclopedia. - M.: Medical Encyclopedia. 1991-96 2. First aid. - M.: Great Russian Encyclopedia. 1994 3. Encyclopedic dictionary of medical terms. - M.: Soviet Encyclopedia. - 1982-1984.

See what "Heart sounds" are in other dictionaries:

HEART TONES- heart sounds, sounds that occur during the work of the heart. Normally, during auscultation of the heart in animals, two clear constant tones are heard - the first and second. The first (systolic) tone occurs during systole when the atrio collapses ... ...

Heart sounds- (soni cordis, from lat. sonus sound, tone + cor, cordis heart) - sounds with a frequency of up to 1000 Hz; occur during the work of the heart; registered on the surface of the chest wall; 5 tones were set: 1st systolic, 2nd diastolic, 3rd ventricular, 4 ... Glossary of terms for the physiology of farm animals

See Heart ... - I Cardiac tamponade (a synonym for tamponade of the pericardial cavity) is a violation of cardiac activity and systemic hemodynamics caused by compression of the heart by fluid that has entered the pericardial cavity. It develops due to an increase in pressure in the cavity ... ... Medical Encyclopedia

Or heart sounds are caused by the slamming of the heart and arterial valves. See Heart for details. The significance of these tones in medicine is great, since with a change in the valves, with their defeat, the character of the Sh. of the heart also changes. Thus, according to ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

EXPANSION OF THE HEART- (Dilatatio cordis), an increase in the cavities of the heart. It occurs as a complication of various myocardial diseases, as well as with nephritis, alveolar emphysema. Cardiac impulse is strengthened (rarely weakened), diffuse, short. The pulse is small, weak filling ... Veterinary Encyclopedic Dictionary

HEART BLOCK- (heart block; the unfortunate name “block” should be left), a break in excitation running through the heart from its sinus node up to the terminal branches of the atrioventricular bundle (see) His Tawara (His Ta wara) so-called ... ...

HEART ARRHYTHMIAS- HEART ARRHYTHMIAS. Contents: Sinus Rhythm Disturbances Tachycardia ................. 216 Bradycardia .................. 217 Sinus arrhythmias .............. ....... 217 Extrasystolic arrhythmia ......... 218 Arhythmia perpetua .............. 224 ... ... Big Medical Encyclopedia

The first phonendoscopes were sheets of paper folded into a tube or hollow bamboo sticks, and many doctors used only their own hearing organ. But they all wanted to hear what was happening inside the human body, especially when it comes to such an important organ as the heart.

Heart sounds are sounds that are formed during the contraction of the walls of the myocardium. Normally, a healthy person has two tones, which may be accompanied by additional sounds, depending on which pathological process develops. A doctor of any specialty must be able to listen to these sounds and interpret them.

Cardiac cycle

The heart beats at a rate of sixty to eighty beats per minute. This, of course, is an average value, but ninety percent of the people on the planet fall under it, which means that you can take it as the norm. Each beat consists of two alternating components: systole and diastole. The systolic heart sound, in turn, is divided into atrial and ventricular. In time, it takes 0.8 seconds, but the heart has time to contract and relax.

Systole

As mentioned above, there are two components involved. First, there is atrial systole: their walls contract, blood enters the ventricles under pressure, and the valve flaps slam shut. It is the sound of closing valves that is heard through the phonendoscope. This entire process takes 0.1 seconds.

Then comes the systole of the ventricles, which is a much more complex work than it happens with the atria. First, note that the process lasts three times longer - 0.33 seconds.

The first period is the tension of the ventricles. It includes phases of asynchronous and isometric contractions. It all starts with the fact that the eclectic impulse spreads through the myocardium, It excites individual muscle fibers and causes them to spontaneously contract. Because of this, the shape of the heart changes. Due to this, the atrioventricular valves close tightly, increasing the pressure. Then there is a powerful contraction of the ventricles, and the blood enters the aorta or pulmonary artery. These two phases take 0.08 seconds, and in the remaining 0.25 seconds, blood enters the great vessels.

Diastole

Here, too, everything is not as simple as it might seem at first glance. The relaxation of the ventricles lasts 0.37 seconds and occurs in three stages:

1. Proto-diastolic: after the blood has left the heart, the pressure in its cavities decreases, and the valves leading to the large vessels close.
2. Isometric relaxation: the muscles continue to relax, the pressure drops even more and equalizes with the atrial. This opens the atrioventricular valves, and blood from the atria enters the ventricles.
3. Filling of the ventricles: fluid fills the lower ventricles along the pressure gradient. When the pressure equalizes, the flow of blood gradually slows down, and then stops.

Then the cycle repeats again, starting with systole. Its duration is always the same, but diastole can be shortened or lengthened depending on the speed of the heartbeat.

The mechanism of formation of I tone

No matter how strange it may sound, but 1 heart sound consists of four components:

1. Valve - he is the leader in the formation of sound. In fact, these are fluctuations of the cusps of the atrioventricular valves at the end of ventricular systole.
2. Muscular - oscillatory movements of the walls of the ventricles during contraction.
3. Vascular - stretching of the walls at the moment when blood enters them under pressure.
4. Atrial - atrial systole. This is the immediate beginning of the first tone.

The mechanism of formation of II tone and additional tones

So, the 2nd heart sound includes only two components: valvular and vascular. The first is the sound that arises from the blows of blood on the valves of the artia and the pulmonary trunk at the moment when they are still closed. The second, that is, the vascular component, is the movements of the walls of large vessels when the valves finally open.

In addition to the two main ones, there are also 3 and 4 tones.

The third tone is the fluctuations of the ventricular myocardium during diastole, when blood passively drains into an area of ​​lower pressure.

The fourth tone appears at the end of systole and is associated with the end of the expulsion of blood from the atria.

Characteristics of the first tone

Heart sounds depend on many causes, both intra- and extracardiac. The sonority of 1 tone depends on the objective state of the myocardium. So, first of all, the volume is provided by the tight closure of the heart valves and the speed with which the ventricles contract. Such features as the density of the cusps of the atrioventricular valves, as well as their position in the cavity of the heart, are considered secondary.

It is best to listen to the first heart sound at its apex - in the 4th-5th intercostal space to the left of the sternum. For more accurate coordinates, it is necessary to percussion the chest in this area and clearly define the boundaries of cardiac dullness.

Characteristic II tone

To listen to him, you need to put the bell of the phonendoscope over the base of the heart. This point is located slightly to the right of the xiphoid process of the sternum.

The volume and clarity of the second tone also depends on how tightly the valves close, only now semilunar. In addition, the speed of their work, that is, the closing and oscillation of the risers, affects the reproduced sound. And additional qualities are the density of all structures involved in the formation of tone, as well as the position of the valves during the expulsion of blood from the heart.

Rules for listening to heart sounds

The sound of the heart is probably the most peaceful in the world, after white noise. Scientists have a hypothesis that it is he who hears the child in the prenatal period. But in order to identify damage to the heart, just listening to how it beats is not enough.

First of all, you need to do auscultation in a quiet and warm room. The posture of the examined person depends on which valve needs to be listened to more carefully. This can be a lying position on the left side, vertically, but with the body tilted forward, on the right side, etc.

The patient should breathe rarely and shallowly, and at the request of the doctor, hold his breath. In order to clearly understand where the systole is and where the diastole is, the doctor must, in parallel with listening, palpate the carotid artery, the pulse on which completely coincides with the systolic phase.

Order of auscultation of the heart

After a preliminary determination of absolute and relative cardiac dullness, the doctor listens to the heart sounds. It starts, as a rule, from the top of the organ. The mitral valve is clearly audible. Then they move on to the valves of the main arteries. First, to the aortic - in the second intercostal space to the right of the sternum, then to the pulmonary artery - at the same level, only on the left.

The fourth point to listen to is the base of the heart. It is located at the base but can move to the sides. So the doctor must check what is the shape of the heart, and the electrical axis to accurately listen

Auscultation is completed at the Botkin-Erb point. Here you can hear She is in the fourth intercostal space on the left side of the sternum.

Additional tones

The sound of the heart does not always resemble rhythmic clicks. Sometimes, more often than we would like, it takes bizarre forms. Doctors have learned to identify some of them only by listening. These include:

Mitral valve click. It can be heard near the apex of the heart, it is associated with organic changes in the valve leaflets and appears only with acquired heart disease.

Systolic click. Another type of mitral valve disease. In this case, its valves do not close tightly and, as it were, turn outward during systole.

Perekardton. Found in adhesive pericarditis. Associated with excessive stretching of the ventricles due to the mooring formed inside.

Rhythm quail. Occurs with mitral stenosis, manifested by an increase in the first tone, an accent of the second tone on the pulmonary artery and a click of the mitral valve.

gallop rhythm. The reason for its appearance is a decrease in myocardial tone, appears against the background of tachycardia.

Extracardiac causes of amplification and weakening of tones

The heart beats in the body throughout life, without interruption and rest. So, when it wears out, outsiders appear in the measured sounds of its work. The reasons for this can be either directly related to damage to the heart, or not depend on it.

Strengthening tones contribute to:

Cachexia, anorexia, thin chest wall;

Atelectasis of the lung or part of it;

Tumor in the posterior mediastinum, moving the lung;

Infiltration of the lower lobes of the lungs;

Bullae in the lungs.

Decreased heart sounds:

Excessive weight;

The development of the muscles of the chest wall;

subcutaneous emphysema;

The presence of fluid in the chest cavity;

Intracardiac causes of amplification and weakening of heart sounds

Heart sounds are clear and rhythmic when the person is at rest or asleep. If he began to move, for example, climbed the stairs to the doctor's office, then this can cause an increase in heart sound. Also, an acceleration of the pulse can be caused by anemia, diseases of the endocrine system, etc.

A muffled heart sound is heard with acquired heart defects, such as mitral or aortic stenosis, valve insufficiency. Aortic stenosis contributes to the divisions close to the heart: the ascending part, the arch, the descending part. Muffled heart sounds are associated with an increase in myocardial mass, as well as with inflammatory diseases of the heart muscle, leading to dystrophy or sclerosis.

Heart murmurs

1. Organic ones appear when anatomical, irreversible changes in the valve system occur in the organ.
2. Functional noises are associated with impaired innervation or nutrition of the papillary muscles, an increase in heart rate and blood flow velocity, and a decrease in its viscosity.

Murmurs may accompany heart sounds or may be independent of them. Sometimes, in inflammatory diseases, it is superimposed on the heartbeat, and then you need to ask the patient to hold his breath or lean forward and auscultate again. This simple trick will help you avoid mistakes. As a rule, when listening to pathological noises, they try to determine in which phase of the cardiac cycle they occur, to find the place of the best listening and to collect the characteristics of the noise: strength, duration and direction.

Noise Properties

According to the timbre, several types of noise are distinguished:

Soft or blowing (usually not associated with pathology, often in children);

Rough, scraping or sawing;

Musical.

According to the duration, they are distinguished:

Short;

Long;

By volume:

loud;

Descending;

Increasing (especially with narrowing of the left atrioventricular orifice);

Increasing-decreasing.

The change in volume is recorded during one of the phases of cardiac activity.

Height:

High-frequency (with aortic stenosis);

Low-frequency (with mitral stenosis).

There are some general patterns in auscultation of noises. Firstly, they are well heard in the locations of the valves, due to the pathology of which they were formed. Secondly, the noise radiates in the direction of blood flow, and not against it. And thirdly, like heart sounds, pathological murmurs are best heard where the heart is not covered by the lungs and is tightly attached to the chest.

It is better to listen in the supine position, because the blood flow from the ventricles becomes easier and faster, and diastolic - sitting, because under gravity, the fluid from the atria quickly enters the ventricles.

Murmurs can be differentiated by their localization and the phase of the cardiac cycle. If the noise in the same place appears both in systole and in diastole, then this indicates a combined lesion of one valve. If, in systole, noise appears at one point, and in diastole - at another, then this is already a combined lesion of two valves.

Carrying out auscultation of the heart is usually carried out sequentially: in the supine (on the back), in the standing position of the patient, and also after physical activity (gymnastics). In order for breath sounds not to interfere with listening to sounds of cardiac origin, before listening, it is necessary to invite the patient to inhale, exhale completely and then hold the breath in the exhalation position. This technique is especially important for beginners in the study of auscultation.

Auscultation of the heart is preferable to produce a mediocre way, with a stethoscope. In view of the fact that the individual places of listening to the heart are located at a very close distance from each other, direct auscultation with the ear is used in exceptional cases to supplement the mediocre one. For a correct assessment of auscultation data, it is necessary to know the places of projection of the heart valves on the chest wall and the places of their best listening, since sound vibrations depend not only on the proximity of the valve apparatus, but also on the conduction of these vibrations through the blood flow.

The projection of the valves on the chest:
1. The valve of the pulmonary trunk lies behind the cartilage of the III left rib near the sternum itself and partly behind it;
2. The aortic valve lies behind the sternum directly below and deeper than the opening of the pulmonary trunk;
3. The mitral valve is projected at the site of attachment to the sternum of the cartilage of the IV left rib;
4. The tricuspid valve lies behind the sternum almost in the middle between the places of attachment of the cartilages of the V right and III of the left ribs.
In healthy people, during auscultation of the heart, two tones are well heard: the I tone that occurs during the systole period is systolic, and the II tone that occurs during the diastole period is diastolic.

Beginning clinicians need to accustom themselves to systematically paying attention to all the features of sound phenomena and pauses. The first task is the orienting definition of the first tone, since the sound cycle of cardiac contraction begins with it. Then, in sequential order, all four holes of the heart are heard.

Listening locations:
The mitral valve tone is heard most clearly at the apex of the heart (1.5 - 2.0 cm medially from the left midclavicular line), the pulmonary artery valve - in the II left intercostal space at the edge of the sternum, the aortic tone - at the edge of the sternum in the II right intercostal space, tricuspid valve - at the base of the xiphoid process of the sternum; the aortic valve is also auscultated at the site of attachment of the III-IV ribs - the Botkin-Erb point (V auscultation point). Listening to the valves is carried out in the indicated sequence, corresponding to the decreasing frequency of their defeat.
For each researcher, it is necessary to determine:
1. strength or clarity of tones;

2. timbre of tones;

3. frequency,

5. presence or absence of noise.

When listening to a healthy heart, two tones are heard, periodically replacing each other. Starting auscultation of the heart from the top, we hear:

1. short, stronger sound - first tone,

2. short first pause,

3. weaker and even shorter sound - second tone

4. second pause, twice as long as the first.

The first tone, unlike the second, is somewhat longer, lower in tone, stronger at the apex, weaker at the base, and coincides with the apex beat. It is more convenient for beginners to distinguish the first tone from the second, focusing on a short pause, that is, guided by the fact that the first tone is heard before it, or, in other words, a short pause follows the first tone. In the case of a frequent heart rhythm, when it is not possible to clearly differentiate the tones, it is necessary, while listening, to attach the fingers of the right hand to the place of the apex beat (or to the carotid artery on the neck). The tone coinciding with the push (or with the pulse on the carotid artery) will be the first. It is impossible to determine the first tone by the pulse on the radial artery, since the latter is late in relation to the first heart sound.

First tone It is made up of 4 main components:

1. Atrial component- associated with fluctuations in the atrial myocardium. Atrial systole precedes ventricular systole, so normally this component merges with the first tone, forming its initial phase.

2. Valve component- fluctuation of the leaflets of atrioventricular valves in the contraction phase. The amount of oscillation of the leaflets of these valves is affected by intraventricular pressure, which in turn depends on the rate of contraction of the ventricles.

3. Muscular component - also occurs during the contraction of the ventricles and is due to myocardial fluctuations.

4. Vascular component- It is formed due to fluctuations in the initial sections of the aorta and pulmonary trunk during the period of expulsion of blood from the heart.

second tone, arising at the beginning of diastole, is formed by 2 main components:
1. Valve component- slamming of the cusps of the aortic and pulmonary valves.
2. Vascular component- fluctuation of the walls of the aorta and pulmonary trunk.

Third tone due to fluctuations that appear with the rapid relaxation of the ventricles, under the influence of blood flow, pouring out of the atria. This tone can be heard in healthy people, mainly in young people and adolescents. It is perceived as a weak, low and muffled sound at the beginning of diastole after 0.12-0.15 s from the beginning of the second tone.

fourth tone precedes the first tone and depends on the fluctuations that occur during atrial contraction. For children and adolescents, it is considered physiological, its appearance in adults is pathological.

The third and fourth tones are heard better with direct auscultation, they are clearly identified when registering a phonocardiogram. The detection of these tones in the elderly, as a rule, indicates severe myocardial damage.

Changes in heart sounds

Muting both tones, observed with a decrease in the contractility of the heart muscle, can be both under the influence of extracardiac causes (excessive subcutaneous fat, anasarca, significant development of the mammary glands in women, pronounced development of the muscles of the chest, emphysema, accumulation of fluid in the cavity of the heart bag: and also as a result of lesions of the heart itself (myocarditis, cardiosclerosis, due to decompensation in various heart diseases).

Strengthening both tones of the heart depends on a number of extracardiac causes (thin chest, retraction of the pulmonary margins, tumors of the posterior mediastinum) and can be observed with thyrotoxicosis, fever, and some intoxications, such as caffeine.

More often there is a change in one of the tones, which is especially important in the diagnosis of heart disease.

Weakening of the first tone at the apex of the heart is observed with mitral and aortic valve insufficiency (due to the absence of a period of closed valves during systole), with narrowing of the aortic orifice and with diffuse myocardial lesions (due to dystrophy, cardiosclerosis, myocarditis) with myocardial infarction.

With insufficiency of the tricuspid valve and the valve of the pulmonary trunk, the weakening of the first tone is observed at the base of the xiphoid process due to the weakening of the muscle and valvular components of these valves. Weakened first sound on the aorta is one of the characteristic acoustic signs of insufficiency of the aortic semilunar valve. This occurs due to an increase in intraventricular pressure above the level of the left atrial at the end of diastole, which contributes to an earlier closure of the mitral valve and limits the amplitude of movement of its valves.

Amplification of the first tone(clapping tone) at the apex of the heart is observed with a decrease in the filling of the left ventricle with blood during diastole and is one of the characteristic signs of stenosis of the left atrioventricular orifice. The reason for its strengthening is the compaction of the leaflets of the mitral valve due to their fibrotic changes. These structural features of the valve determine the change in the frequency-amplitude characteristics of the first tone. Dense tissues are known to generate higher frequency sounds. The first tone ("Strazhesko's cannon tone") is especially loud with complete atrioventricular blockade of the heart, when there is a simultaneous contraction of the atria and ventricles. Strengthening of the first tone at the base of the xiphoid process is observed with stenosis of the right atrioventricular orifice; it can also be observed with tachycardia and extrasystole.

Weakening of the second tone above the aortic valve is observed with its insufficiency or due to partial or complete destruction of the aortic valve cusps (in the second case, the II tone may be completely absent), or with their cicatricial compaction. The weakening of the second tone on the pulmonary artery is noted with insufficiency of its valve (which is extremely rare) and with a decrease in pressure in the pulmonary circulation.

Amplification of the second tone on the aorta is observed with an increase in pressure in the systemic circulation in diseases accompanied by arterial hypertension (hypertension, glomerulonephritis, polycystic kidney disease, etc.). A sharply increased second tone (clangor) is observed in syphilitic mesaortitis. An increase in the second tone on the pulmonary artery is ascertained with an increase in pressure in the pulmonary circulation (mitral heart disease), difficulty in blood circulation in the lungs (pulmonary emphysema, pneumosclerosis). If this tone is louder over the aorta, they talk about the accent of the second tone on the aorta, if it is louder over the pulmonary trunk, they talk about the accent of the II tone on the pulmonary artery.

Bifurcation of heart sounds.

Heart sounds, terms t several components are perceived as a single sound. Under some physiological and pathological conditions, there is no synchronism in the sound of those components that take part in the formation of a particular tone. There is a split tone.

Bifurcation of tones is the selection of the components that make up the tone. The latter follow each other at short intervals (after 0.036 s or more). The mechanism of bifurcation of tones is due to asynchronism in the activity of the right and left halves of the heart: non-simultaneous closing of the atrioventricular valves leads to a bifurcation of the first tone, semilunar valves - to a bifurcation of the second tone. Bifurcation of tones can be physiological and pathological. Physiological bifurcation (splitting) of I tone occurs when the atrioventricular valves close asynchronously. This may be during a deep exhalation, when, due to an increase in pressure in the pulmonary circulation, blood enters the left atrium with greater force and prevents the mitral valve from closing in time.

Physiological split II tone It manifests itself in connection with various phases of respiration, since when inhaling and exhaling, the blood filling of the left and right ventricles changes, and, consequently, the duration of their systole and the closing time of the corresponding valves. The bifurcation of the second tone is especially well detected during auscultation of the pulmonary artery. The physiological bifurcation of the II tone is not permanent (non-fixed bifurcation), is closely related to the normal mechanism of respiration (it decreases or disappears during inspiration), while the interval between the aortic and pulmonary components is 0.04-0. Obs.

Pathological bifurcation of tones may be due to the following factors:

1. Hemodynamic (increase in systolic volume of one of the ventricles, increase in diastolic pressure in one of the ventricles, increase in diastolic pressure in one of the vessels);

2. Violation of intraventricular conduction (blockade of the legs of the bundle of His);

3. Weakening of the contractile function of the myocardium;

4. Ventricular extrasystole.

Pathological bifurcation of the I tone may be in violation of intraventricular conduction (along the legs of the bundle of His) due to a delay in the next contraction of one of the ventricles.

Pathological bifurcation II tone is observed with arterial hypertension, with stenosis of the aortic orifice, when the aortic valve flaps slam shut later than the pulmonary valve; in the case of increased pressure in the pulmonary circulation (with emphysema, mitral stenosis, etc.), when, on the contrary, the valve of the pulmonary trunk lags behind.

From bifurcation of tones it is necessary to distinguish the appearance additional tones.

These include mitral valve opening tone, auscultated during narrowing of the left atrioventricular orifice. The mechanism of its occurrence is associated with a sudden tension of sclerosed valve cusps, unable to move completely to the walls of the ventricle during the passage of blood from the left atrium to the left ventricle. The tone of the mitral valve opening occurs immediately after the II tone after 0.07-0.13s, during the diastole period. It is best heard at the apex, combined with other auscultatory signs of mitral stenosis. In general, an additional third mitral valve opening sound, combined with a loud (clapping) first heart sound and a second heart sound, form a three-term rhythm resembling a quail cry, - quail rhythm.

The three-term rhythm also includes rhythm gallop reminiscent of the tramp of a galloping horse. There are presystolic gallop rhythm, which is caused by a pathological IV heart sound and a summation gallop rhythm, the occurrence of which is associated with the imposition of III and IV tones; an additional tone with this rhythm is usually heard in the middle of diastole. A gallop rhythm is heard in severe myocardial damage (myocardial infarction, myocarditis, chronic nephritis, hypertension, etc.).

With severe tachycardia, there is a shortening of the diastolic pause to the size of the systolic one. At the top of I and II, the tones become almost identical in sonority, which served as the basis for calling such an auscultatory picture pendulum rhythm or, similar to the fetal heartbeat, embryocardia. This can be observed in acute heart failure, paroxysmal tachycardia, high fever, etc.

Heart murmurs

Noises can occur both inside the heart (intracardiac) and outside it (extracardiac).

The main mechanisms for the formation of intracardiac murmurs are changes in the size of the openings of the heart and changes in the speed of blood flow. Their occurrence may depend on the rheological properties of the blood, and sometimes on the irregularities of the endocardial valves, as well as the state of the intima of the vessels.

Intracardiac murmurs are classified into organic, which are caused by anatomical changes in the openings and valve apparatus (acquired and congenital malformations) and inorganic or functional, arising from anatomically intact valves and associated with changes in the activity of the heart, with a decrease in blood viscosity

An intermediate position between organic and functional murmurs is occupied by murmurs of relative muscular insufficiency of valves. Relative valve insufficiency noise occurs during dilatation of the ventricles, and, consequently, the expansion of the atrioventricular orifice, and therefore even an unchanged valve cannot completely close it. With improvement in myocardial contractility, the noise may disappear. A similar mechanism occurs in violation of the tone of the papillary muscles.

According to the time of appearance of the noise in relation to the phases of cardiac activity, systolic and diastolic heart murmurs are distinguished.

Systolic murmurs are heard between I and D tones (in a short pause), and diastolic murmurs - between P and the next I tone (in a long pause). Noise can occupy the entire pause or only part of it. By hemodynamic origin, ejection murmurs and regurgitation murmurs are distinguished.

Systolic murmurs can be organic and functional, and are usually stronger than diastolic murmurs in intensity.

Systolic murmur It occurs when blood meets an obstacle in its path. It is divided into two main types:

1. Systolic ejection murmur(with stenosis of the mouth of the aorta or pulmonary trunk: since during the expulsion of blood from the ventricles, a narrowing of the vessel occurs on the path of blood flow);

2. Systolic murmur of regurgitation(with insufficiency of the mitral or tricuspid valves; in these cases, in the systole of the ventricles, the blood goes not only to the aorta and pulmonary trunk, but also back to the atria through an incompletely covered atrioventricular opening.) Diastolic murmur occurs either with stenosis of the atrioventricular openings, because during diastole there is a narrowing in the path of blood flow from the atria to the ventricles, or in case of insufficiency of the aortic valve or pulmonary valve - due to the reverse flow of blood from the vessels to the ventricles in the diastole phase.

According to their properties, noises are distinguished:

1. by timbre (soft, blowing; or rough, scraping, sawing);

2. by duration (short and long),

3. by volume (quiet and loud);

4. by intensity in dynamics (decreasing or increasing noise);

PLACES OF THE BEST LISTENING AND NOISE CONDUCTIVITY:

Noises are heard not only in the classical places of listening to tones, but also at some distance from them, especially along the path of blood flow. With aortic stenosis the murmur is conducted into the carotid and other major arteries and is even heard on the back at the level of I-III thoracic vertebrae. Murmur of aortic valve insufficiency carried out, on the contrary, to the ventricle, i.e. to the left down, and the place of listening passes along this line to the sternum, to its left edge, at the place of attachment of the third costal cartilage. In the initial stages of damage to the aortic valves, for example, with rheumatic endocarditis, a gentle diastolic murmur, as a rule, is not heard in the usual place (the second intercostal space on the right), but only at the left edge of the sternum in the third or fourth intercostal space - at the so-called fifth point. Noise due to bicuspid valve insufficiency carried up to the second intercostal space or to the left to the armpit. With ventricular septal insufficiency the noise spreads across the sternum from left to right.

All conduction noises lose strength in proportion to the square of the distance; this circumstance helps to understand their localization. In the presence of mitral valve insufficiency and stenosis of the aortic orifice, we, going from the top along the line connecting the places of their listening, will first hear a decreasing noise of moral insufficiency, and then an increasing noise of aortic stenosis. Only presystolic noise at a mitral stenosis has very small scope of distribution; sometimes it is auscultated in a very limited area.

Systolic murmurs of aortic origin (narrowing of the mouth, irregularities of the aortic wall, etc.) are well heard in the suprasternal fossa. With a significant expansion of the left atrium, the systolic murmur of mitral insufficiency is sometimes heard to the left of the spine at the level of the VI-VII thoracic vertebrae.

diastolic murmurs ,

depending on which part of the diastode occurs, they are divided into protodiastolic (at the beginning of the diastole, Greek protos - the first), mesodiastolic (occupying only the middle of the diastole, Greek mesos - middle) and presystolic or telediastolic (at the end of the diastole, increasing to noise of the first tone, Greek telos - end). The vast majority of diastolic murmurs are organic. Only in some cases they can be heard without the presence of organic damage to the valves and orifices.

Functional diastolic murmurs.

There are functional presystolic flint noise when, in aortic valve insufficiency, the back wave of blood lifts the leaflet of the moral valve, narrowing the left atrioventricular orifice, thereby creating relative mitral stenosis. mesodiastolic Coombs noise may occur at the beginning of an attack of rheumatism due to edema of the left atrioventricular orifice and the occurrence of its relative stenosis. When removing the exudative phase, the noise may disappear. Graham-Still noise can be determined in diastole over the pulmonary artery, when stagnation in the small circle causes stretching and expansion of the pulmonary artery, in connection with which there is a relative insufficiency of its valve.

In the presence of noise, it is necessary to determine its relation to the phases of cardiac activity (systolic or diastolic), to clarify the place of its best listening (epicenter), conductivity, strength, variability and character.

Characteristics of murmurs in some heart defects.

mitral valve insufficiency characterized by the presence of a systolic murmur at the apex of the heart, which is heard along with a weakened I tone or instead of it, decreases towards the end of systole, is quite sharp, rough, well conducted into the armpit, better heard in the position of the patient on the left side.

At stenosis of the left atrioventricular orifice the noise occurs in the mesodiastole, is of an increasing nature (crescendo) is heard at the apex, is not conducted anywhere. Often ends with a clapping I tone. It is better defined in the position of the patient on the left side. Presystolic noise, clapping I tone and "double" II-nd give a typical melody of mitral stenosis.

At aortic valve insufficiency diastolic murmur begins immediately after tone II, in protodiastole, gradually decreasing towards its end (decrescendo), better heard at point 5, less pronounced in the 2nd intercostal space to the right of the sternum, carried out at the apex of the heart, the murmur is soft, better heard during breath holding after deep breath. It is best heard in the patient's standing position, especially when the torso is tilted forward.

In cases aortic stenosis systolic murmur is heard in the second intercostal space on the right at the edge of the sternum. It is very sharp, rough, muffles the I tone, is auscultated throughout the systole and is most conductive, well auscultated on the vessels of the neck, on the back along the spine.

At tricuspid valve insufficiency The maximum sound of the noise is determined at the base of the xiphoid process of the sternum. With organic valve damage, the systolic murmur is rough, clear, and with relative valve insufficiency, it is softer, blowing.

Of the rarer defects, in which systolic murmur is determined, indicate stenosis of the orifice of the pulmonary artery(the maximum of its sounding is in the second intercostal space to the left of the sternum, it is carried out to the left collarbone and to the left half of the neck); cleft of the Botallian duct(systole-diastolic murmur in 3-4 intercostal spaces); ventricular septal defect(in the 4th intercostal space, somewhat outward from the left edge of the sternum, it is carried out in the form of "wheel spokes" - from the epicenter of the noise in a circle, loud, sharp in timbre).

Extracardiac (extracardiac) murmurs.

Noises can occur not only inside the heart, but also outside it, synchronously with heart contractions. Distinguish between pericardial murmur or pericardial friction murmur and pleuropericardial friction murmur.

Pericardial murmur it is heard mainly due to inflammatory phenomena in the pericardium, in myocardial infarction, in tuberculosis with fibrin deposition, etc. Pericardial friction noise is characterized by:

1. It is either barely perceptible, or very rough, with direct auscultation sometimes even causes discomfort, as it is heard directly under the ear,

2. Noise is associated with the phases of cardiac activity, but not exactly: it goes from systole to diastole and vice versa (in systole it is usually stronger);

3. Almost never radiates,

4. Variable in location and time;

5. When leaning forward, when standing on all fours, and when pressing with a stethoscope, the noise increases.

Along with pericardial murmur, false pericardial (pleuropericardial) rubbing noise is distinguished, associated with dry pleurisy of the parts of the pleura adjacent to the heart, mainly on the left. Contractions of the heart, increasing the contact of the pericardium and pleura, contribute to the appearance of friction noise. The difference from the true pericardial murmur is that it is heard only with deep breathing, intensified during inspiration and localized mainly at the left edge of the heart.

Cardiopulmonary murmurs arise to the parts of the lungs adjacent to the heart, straightening out during systole due to a decrease in the volume of the heart. Air, penetrating into this part of the lungs, gives a vesicular noise in nature ("vesicular breathing") and systolic in time.

Auscultation of arteries and veins.

In a healthy person, you can listen to tones on medium-sized arteries (carotid, subclavian, femoral, etc.). As in the heart, two tones are often heard on them. The arteries are preliminarily palpated, then a stethoscope funnel is attached, trying not to compress the vessel, avoiding the occurrence of stenotic noise.

Normally, two tones (systolic and diastolic) are heard on the carotid and subclavian arteries. On the femoral artery, only the first, systolic tone can be heard. In both cases, the first tone is partially wired, partially formed at the site of auscultation. The second tone is completely conducted from the semilunar valves.

The carotid artery is heard at the level of the larynx from the inside m. Stemo-cleido-mastoidei, and subclavian - on its outer side, immediately above the clavicle or below the clavicle in its outer third. Listening to other arteries does not give tones.

In case of insufficiency of the aortic valve with a pronounced fast pulse (pulsus celer), tones can also be heard above the arteries, where they are usually not heard - above the abdominal aorta, brachial, radial arteries. Over the femoral artery with this defect, two tones are sometimes heard ( Traube double tone), due to sharp fluctuations of the vascular wall both in the phase of systole and in diastole. In addition, tones in the peripheral arteries can occur with pronounced left ventricular hypertrophy and thyrotoxicosis due to increased vascular pulsation.

Noises can also be heard above the arteries. This is observed in the following cases:

1. Wired blood flow in aortic stenosis, atherosclerosis with intima changes and aneurysms;

2. Systolic, associated with a decrease in blood viscosity and an increase in blood flow velocity (with anemia, fever, thyrotoxicosis;

3. Local - when the artery is compressed from the outside (for example, by pleural stitches around the subclavian artery), its sclerotic stenosis, or, conversely, with its aneurysm;

4. in case of insufficiency of the aortic valve on the femoral artery with a slight compression of it, it is heard double Vinogradov-Durozier noise, in the first phase caused by a squeezed stethoscope, in the second, probably by a reverse flow of blood.

When listening to the veins, they use exclusively auscultation of the bulb of the jugular vein above the clavicle, more often on the right. The stethoscope must be placed very carefully to avoid compression noise. With a decrease in blood viscosity, due to an increase in blood flow in patients with anemia, noise is heard here, continuously, almost regardless of heart contractions. By nature it is musical and low and is called "the noise of the top". This noise is heard better when turning the head in the opposite direction. This noise has no particular diagnostic value, especially since it can rarely be observed in healthy people.

In conclusion, it should be noted that in order to hear the heart, one must learn to listen to it. First, it is necessary to repeatedly listen to healthy people with a slow heart rate, then with tachycardia, then with atrial fibrillation, setting ourselves the task of distinguishing tones. Gradually, as experience is gained, the analytical method of studying the heart melody must be replaced by a synthetic one, when the totality of the sound symptoms of one or the other. another defect is perceived as a whole, which speeds up the diagnostic process. However, in complex cases, one should try to combine these two approaches to the study of acoustic phenomena of the heart. For novice doctors, a detailed verbal description of the heart melody of each patient, produced in a certain sequence, repeating the sequence of auscultation, is considered very useful. The description should include a description of the heart sounds at all listening points, as well as the main properties of the noise. It is advisable to use the graphical representation of the heart melody used in clinics. Both of these methods are aimed at cultivating the habit of systematic auscultation.

Self-education of auscultation should be practiced stubbornly, without being upset by the inevitable failures at first. It should be remembered that "the period of learning auscultation lasts a lifetime."