home Audience 8 Deviation of eos to the right, which means in an adult. Electrical axis of the heart. What should be its normal position?

Deviation of eos to the right, which means in an adult. Electrical axis of the heart. What should be its normal position?

If the electrical axis of the heart (EOS) is deviated to the left or right, then this may indicate violations of the work of this organ. Consider why this can happen, when it is dangerous, and when it is not, and how this condition is treated.

The position of this axis is determined using electrocardiography, after analyzing the electrocardiogram from several leads.

2 methods can be used to detect a change in the normal position of the axis.

Deviation alpha - angle

This technique is most often used by diagnosticians. Normally, the EOS completely coincides with the anatomical axis (the heart is located semi-vertically, and the lower end deviates down and slightly to the left). Its location is determined by the alpha - angle formed from 2 straight lines (1 axis of abduction and the line of the EOS vector).

To identify the angle, the sum of the S, R and Q waves in 3 and 1 standard leads is calculated. Be sure to take into account the positive and negative value each tooth.

The Died table is then used. Having put the result in it, the doctor determines the criteria for the alpha angle.

Here's what it looks like:

Click on the picture to enlarge

Normally, this angle should be from -29° to +89°. Significant left-sided axle offset is a sign pathological disorders. When it changes to -30° we are talking about left-sided deviation, and for values from +90° to +180° - right-sided.

Left-sided deviation of the angle from -30° to -44° is insignificant, at -45° to -90° it is considered significant and in most cases accompanies cardiac pathologies.

Visual Definition

This technique for determining the displacement of the axis of the heart is most often used by therapists and cardiologists. After the ECG, the doctor compares the size of the S and R waves in leads 1 and 3. If in the border of one of them the value of R is greater than S, we are talking about a ventricular complex (according to R-type). Otherwise, the complex belongs to the S-type.

When the axis deviates to the left, the tooth RI - SIII. This means that the ventricular complex is R-type in lead 1 and S-type in lead 3.

Standard abduction of QRS teeth in different positions of the EOS (a, b - right-sided displacement; c - normal position of the axis; d, e - left-sided displacement)

The main tool for determining EOS deviations to the left is electrocardiography, however, a number of auxiliary studies are needed to confirm the result.

Additional diagnostic methods

After an ECG is performed, its results are carefully examined to determine the cause. pathological condition. In most cases, a repeated cardiogram is prescribed, which is necessary to eliminate technical errors (incorrect placement of electrodes, device malfunction, etc.).

- if the doctor diagnoses a conduction disorder or arrhythmia on an ECG, then 24-hour monitoring of cardiac activity (daily ECG) is performed, which makes it possible to more accurately determine the area of \u200b\u200bthe heart with impaired conduction.
This research is aimed at obtaining more information about cardiac output, blood flow, the state of the heart chambers. When indicated, ultrasound can be supplemented with dopplerography.
- assigned at sharp rise BP against the background of left ventricular hypertrophy with deviation of the cardiac axis. This examination allows you to determine the stage hypertension and determine the most appropriate treatment.
Cardiosurgical consultation - is prescribed for any pathologies of the heart, and especially for defects with a tendency to progression.

It must be taken into account that the deviation of the EOS to the left is just ECG sign pointing to diffuse changes at various pathologies, therefore, a comprehensive diagnosis is mandatory.

Reasons for bias

Changes in the activity of the heart on the electrocardiogram are provoked by many factors.

Let's consider each case in more detail.

Heart disease

The main reason for the shift to the left of the axis of the heart is left ventricular hypertrophy. Changes can provoke: ischemia (including heart attacks and), aortic and mitral valve, cardiomyopathy, myocardial dystrophy and other diseases.

Cardiogram changes are possible with atrial fibrillation, heart defects (acquired and congenital), blockade of the left leg of the bundle of His.

Physiological states

A slight deviation of the EOS on electrocardiography is often found in quite healthy people, for example, athletes, in lean and tall patients.

The electrical axis can shift to the left during deep expiration, high diaphragm and when the body position changes (from vertical to horizontal), which is due to compression of the diaphragm by internal organs. Such shifts are considered quite normal.

In what cases is EOS deviated in children?

In children, EOS may change according to age. For example, newborns are characterized by right-sided deviation and this is not a pathology. IN adolescence the EOS angle has stable performance.

Most often in children, left-sided axis deviation (up to -90 °) is caused by birth defects that can be complicated by concomitant cardiovascular anomalies. This is possible with an open ductus arteriosus, in case of high loads on the left ventricle, which happens with mitral heart disease or aortic coarctation. Such a picture in a child is possible with a defect interventricular septa or with a high standing diaphragmatic dome.

Axial shift to the left (from 0 to -20°) is also possible due to a change in the position of the ventricles. Congenital heart disease with incomplete atrioventricular communication, as well as defects interatrial septum, are also accompanied by a change in the axis from –20° to –60°.

Clinical manifestations

The displacement of the EOS is not a disease, therefore, it is not characterized by certain Clinical signs. In addition, the pathologies by which it is caused can also occur with erased symptoms. In this case, deviations of the electrical axis of the heart to the left are often detected only when deciphering the electrocardiogram.

There are certain symptoms inherent in certain diseases. For example, with hypoxia of the left ventricle, they are expressed by paroxysmal pain in the chest and jumps in blood pressure. There may be tachycardia and severe headache. With the blockade of the left leg of the bundle of His, fainting and bradycardia are possible.

Treatment

Deviation of the axis of the heart to the left does not provide for the use specific therapy. All activities are aimed at neutralizing the underlying disease, accompanied by a shift in the EOS and a violation. For arterial hypertension, antihypertensive drugs, ischemia requires the use ACE inhibitors, statins, beta-blockers.

The deviation of the EOS does not pose a threat to the patient's life, but if the position of the axis changes very sharply, there is a possibility of blockade of the legs of the His. If such changes are detected, a mandatory consultation with a cardiologist is required to clarify the diagnosis. This approach makes it possible to identify border state in the work of the heart.

Methods for determining the position of the EOS.

1. Visual.

2. Graphic - using various systems coordinates (Einthoven triangle, 6-axis Bailey scheme, Died scheme).

3. From tables or charts.

Visual determination of the position of the EOS - used for a rough estimate.

1 way. Score on 3 standard leads.

To determine the position of the EOS, pay attention to the severity of the amplitude of the R waves and the ratio of the R and S teeth in standard leads.

Note: if you write the standard leads in Arabic numerals (R 1, R 2, R 3), then it is easy to remember the serial number of digits according to the size of the R wave in these leads: normogram - 213, rightogram - 321, leftogram - 123.

2 way. Assessment using 6 limb leads.

To determine the position of the EOS, they are first guided by three standard leads, and then pay attention to the equality of the R and S teeth in standard and reinforced ones.

3 way. Assessment using the 6-axis Bailey system (limb leads).

This method gives a more accurate estimate. To determine the position of the EOS, it is necessary to take successive steps.

Step 1. Find the lead in which the algebraic sum of the amplitudes of the QRS complex teeth approaches 0 (R=S or R=Q+S). The axis of this assignment is approximately perpendicular to the desired EOS.

Step 2 Find one or two leads in which the algebraic sum of the QRS complex teeth has a positive maximum value. The axes of these leads approximately coincide with the direction of the EOS

Step 3 Compare the results of the first and second steps, draw the final conclusion. Knowing at what angle the lead axes are located, determine the angle α.

To determine the angle α by a graphical method or according to the tables of R.Ya.Pismenny it is necessary to calculate the algebraic sum of the amplitudes of the QRS complex teeth sequentially in I, and then in III standard leads. To obtain the algebraic sum of the teeth of the QRS complex in any lead, it is necessary to subtract the amplitude of the negative teeth from the amplitude of the R wave, i.e. S and Q. If the dominant wave of the QRS complex is R, then the algebraic sum of the waves will be positive, and if S or Q is negative.

The obtained values are plotted on the axes of the corresponding leads and graphically determine the angle α in any of the listed coordinate systems. Or, using the same data, the angle α is determined according to the tables of R.Ya. Pismenny (see tables 5, 6, 7 of the appendix, in the same place - the rules for using the tables).

Exercise: on the ECG, independently calculate the angle α and determine the position of the EOS using the listed methods.

6. Analysis of waves, intervals, ECG complexes

6.1. Tooth R. Analysis of the P wave involves determining its amplitude, width (duration), shape, direction and severity in various leads.

6.1.1. Determination of the amplitude of the P wave and its assessment. The P wave is small, from 0.5 to 2.5 mm. Its amplitude should be determined in the lead where it is most clearly expressed (most often in I and II standard leads).

6.1.2. Determination of the duration of the P wave and its assessment. The P wave is measured from the beginning of the P wave to its end. Normative indicators for evaluation are given in Table 3 of the Appendix.

6.1.3. The severity and direction of the P wave depend on the magnitude and direction of the electric axis of the vector P, which occurs during excitation of the atria. Therefore, in different leads, the magnitude and direction of the P wave change from a well-defined positive to a smooth, biphasic or negative. The P wave is more pronounced in the leads from the extremities and weakly in the chest leads. In most leads, a positive P wave predominates (I, II, aVF, V 2 -V 6), because the P vector is projected onto the positive parts of most leads (but not all!). The always negative wave of the P vector is projected onto the positive parts of most leads (but not all!). negative P wave in lead aVR. In leads III, aVL, V 1 may be weakly positive or biphasic, and in III, aVL may sometimes be negative.

6.1.4. P wave shape should be flat, rounded, domed. Sometimes there may be a slight serration at the top due to non-simultaneous excitation coverage of the right and left atria (no more than 0.02-0.03 s).

6.2. PQ interval. The PQ interval is measured from the beginning of the P wave to the beginning of the Q wave (R). For measurement, choose the lead from the extremities, where the P wave and the QRS complex are well expressed, and in which the duration of this interval is the longest (usually II standard lead). In the chest leads, the duration of the PQ interval may differ from its duration in the limb leads by 0.04 s or even more. Its duration depends on age and heart rate. The younger the child and the higher the heart rate, the shorter the PQ interval. Regulatory indicators for evaluation are given in Table 3 of the Appendix.

6.3. QRS complex - the initial part of the ventricular complex.

6.3.1. The designation of the teeth of the QRS complex, depending on their amplitude. If the amplitude of the R and S waves is greater than 5 mm, and Q is greater than 3 mm, they are designated capital letters Latin alphabet Q, R, S; if less then lower case q, r, s.

6.3.2. The designation of the teeth of the QRS complex in the presence of several R or S waves in the complex. If there are several R waves in the QRS complex, they are designated R, R', R” (r, r', r”), respectively, if there are several S waves, then - S, S', S” (s, s', s” ). The sequence of teeth is as follows - the negative wave preceding the first R wave is denoted by the letter Q (q), and the negative wave immediately following the R wave and before the R’ wave is denoted by the letter S (s).

6.3.3. The number of teeth of the QRS complex in different leads. The QRS complex can be represented by three teeth - QRS, two - QR, RS, or one tooth - R or QS complex. It depends on the position (orientation) of the QRS vector in relation to the axis of a given lead. If the vector is perpendicular to the axis of abduction, then 1 or even 2 teeth of the complex may not be registered.

6.3.4. Measurement of the duration of the QRS complex and its assessment. The duration of the QRS complex (width) is measured from the beginning of the Q wave (R) to the end of the S wave (R). It is best to measure the duration in standard leads (usually in II), while taking into account the largest width of the complex. With age, the width of the QRS complex increases. Normative indicators for evaluation are given in Table 3 of the Appendix.

6.3.5. QRS complex amplitude (ECG voltage) varies considerably. In the chest leads, it is usually greater than in the standard ones. The amplitude of the QRS complex is measured from the top of the R wave to the top of the S wave. Normally, according to at least in one of the standard or enhanced limb leads, it should exceed 5 mm, and in the chest leads - 8 mm. If the amplitude of the QRS complex is less than the above figures or the sum of the amplitudes of the R waves in the three standard leads is less than 15 mm, then the ECG voltage is considered reduced. An increase in voltage is considered to be an excess of the maximum allowable amplitude of the QRS complex (in the lead from the limbs - 20-22 mm, in the chest - 25 mm). However, it should be borne in mind that the terms "decrease" and "increase" in voltage ECG waves do not differ in the accuracy of the adopted criteria, because there are no standards for the amplitude of the teeth, depending on the type of physique and different thickness chest. Therefore, it is not so important absolute value teeth of the QRS complex, how much is their ratio in terms of amplitude indicators.

6.3.6. Comparison of amplitudes and R and S waves in different leads important to determine

- EOS directions(angle α in degrees) – see section 5;

- transition zone. So called chest lead, in which the amplitude of the R and S waves is approximately the same. When moving from the right to the left chest leads, the R/S wave ratio gradually increases, because the height of the R teeth increases and the depth of the S teeth decreases. The position of the transitional zone changes with age. In healthy children (except for children of 1 year of age) and adults, it is more often recorded in lead V 3 (V 2 -V 4). Analysis of the QRS complex and transitional zone allows you to assess the dominance electrical activity right or left ventricles and turns of the heart around the longitudinal axis clockwise or counterclockwise. The localization of the transition zone in V 2 -V 3 indicates the dominance of the left ventricle;

- rotations of the heart around the axes(anteroposterior, longitudinal and transverse).

6.4. Q wave. Analysis of the Q wave involves determining its depth, duration, severity in various leads, comparison in amplitude with the R wave.

6.4.1. Depth and width of the Q wave. More often, the Q wave has a small size (up to 3 mm, type q) and a width of 0.02-0.03 s. In lead aVR, a deep (up to 8 mm) and wide Q wave, such as Qr or QS, can be recorded. An exception is also Q III, which can be up to 4-7 mm deep in healthy individuals.

6.4.2. The severity of the Q wave in various leads. The Q wave is the most unstable ECG wave, so it may not be recorded in some of the leads. More often it is determined in the limb leads, more pronounced in I, II, aVL, aVF and, especially, in aVR, as well as in the left chest (V 4 -V 6). In the right chest, especially in leads V 1 and V 2, as a rule, is not recorded.

6.4.3. The ratio of the amplitude of the Q and R waves. In all leads where the Q wave is recorded (except aVR), its depth should not exceed ¼ of the amplitude of the R wave following it. The exception is lead aVR, in which the deep Q wave significantly exceeds the amplitude of the r wave.

6.5. Prong R. Analysis of the R wave involves determining the severity in different leads, amplitude, shape, interval of internal deviation, comparison with the S wave (sometimes with Q) in different leads.

6.5.1. The severity of the R wave in different leads. The R wave is the highest ECG wave. The highest R waves are recorded in the chest leads, slightly less high in the standard leads. The degree of its severity in different leads is determined by the position of the EOS.

- In the normal position of the EOS in all leads from the extremities (except aVR), high R waves are recorded with a maximum in the II standard lead (with R II > R I > R III). In the chest leads (except for V 1), high R waves are also recorded with a maximum in V 4 . At the same time, the amplitude of the R waves increases from left to right: from V 2 to V 4, then from V 4 to V 6, it decreases, but the R waves in the left chest leads are higher than in the right ones. And only in two leads (aVR and V 1) R waves have a minimum amplitude or are not recorded at all, and then the complex looks like QS.

- the highest R wave is recorded in lead aVF, the R waves are somewhat smaller in standard leads III and II (with R III > R II > R I and R aVF > R III), and in leads aVL and standard I, R waves are small, in aVL are sometimes absent.

- the highest R waves are recorded in I standard and aVL leads, somewhat less - in II and III standard leads (with R I > R II > R III) and in lead aVF.

6.5.2. Determination and assessment of the amplitude of the R waves. Fluctuations in the amplitude of the R waves in various leads range from 3 to 15 mm, depending on age, the width is 0.03-0.04 sec. The maximum allowable height of the R wave in standard leads is up to 20 mm, in chest leads - up to 25 mm. Determining the amplitude of the R waves is important for assessing the ECG voltage (see section 6.3.5.).

6.5.3. R wave shape should be smooth, pointed, without notches and splits, although their presence is allowed if they are not at the top, but closer to the base of the tooth, and if they are determined in only one lead, especially on low R waves.

6.5.4. Determination of the interval of internal deviation and its evaluation. The interval of internal deviation gives an idea of the duration of activation of the right (V 1) and left (V 6) ventricles. It is measured along the isoelectric line from the beginning of the Q wave (R) to the perpendicular, lowered from the top of the R wave to the isoelectric line, in chest leads (V 1, V 2 - right ventricle, V 5, V 6 - left ventricle). The duration of ventricular activation in the right chest leads changes little with age, while in the left it increases. Norm for adults: in V 1 no more than 0.03 s, in V 6 no more than 0.05 s.

6.6. S tooth. Analysis of the S wave involves determining the depth, width, shape, severity in different leads and comparing with the R wave in different leads.

6.6.1. Depth, width and shape of the S wave. The amplitude of the S wave varies widely: from the absence (0 mm) or small depth in a few leads (especially in standard ones) to a large value (but not more than 20 mm). More often, the S wave is shallow (2 to 5 mm) in limb leads (except aVR) and quite deep in leads V 1 -V 4 and in aVR. The width of the S wave is 0.03 s. The shape of the S wave should be smooth, pointed, without nicks and splits.

6.6.2. The severity of the S wave (depth) in different leads depends on the position of the EOS and changes with age.

- In the normal position of the EOS in limb leads, the deepest S wave is found in aVR (rS or QS type). In the remaining leads, an S wave of small depth is recorded, most pronounced in the II standard and aVF leads. In the chest leads, the greatest amplitude of the S wave is usually observed in V 1, V 2 and gradually decreases from left to right from V 1 to V 4, and in leads V 5 and V 6, the S waves are small or not recorded at all.

- With the vertical position of the EOS the S wave is most pronounced in leads I and aVL.

- With a horizontal position of the EOS the S wave is most pronounced in leads III and aVF.

6.7. ST segment - a segment from the end of the S (R) wave to the beginning of the T wave. Its analysis involves determination of isoelectricity and degree of displacement. To determine the isoelectricity of the ST segment, one should be guided by the isoelectric line of the TP segment. If the TR segment is not located on the isoline or is poorly expressed (with tachycardia), they are guided by the PQ segment. The junction of the end of the S wave (R) with the beginning of the ST segment is indicated by the dot "j". Its location is important in determining the offset of the ST segment from the isoline. If there is ST segment displacement, it is necessary to indicate its size in mm and describe the shape (convex, concave, horizontal, oblique, oblique, etc.). In a normal ECG, the ST segment does not completely coincide with the isoelectric line. The exact horizontal direction of the ST segment in all leads (except III) can be considered pathological. The deviation of the ST segment in leads from the limbs up to 1 mm up and up to 0.5 mm down is allowed. In the right chest leads, a deviation of up to 2 mm upwards is allowed, and in the left - up to 1.0 mm (more often downwards).

6.8. Tooth T. Analysis of the T wave involves determining the amplitude, width, shape, severity and direction in various leads.

6.8.1. Determination of the amplitude and duration (width) of the T wave. There are fluctuations in the amplitude of the T wave in different leads: from 1 mm to 5-6 mm in leads from the extremities to 10 mm (rarely up to 15 mm) in the chest. The duration of the T wave is 0.10-0.25 s, but it is determined only in pathology.

6.8.2. T wave shape. The normal T wave is somewhat asymmetrical: it has a gently sloping upward bend, a rounded tip, and a steeper downward bend.

6.8.3. The severity (amplitude) of the T wave in different leads. The amplitude and direction of the T wave in various leads depend on the magnitude and orientation (position) of the ventricular repolarization vector (T vector). The vector T has almost the same direction as the vector R, but a smaller magnitude. Therefore, in most leads, the T wave is small and positive. At the same time, the largest R wave in various leads corresponds to the largest T wave in amplitude and vice versa. In standard leads T I > T III . In the chest - the height of the T wave increases from left to right from V 1 to V 4 with a maximum to V 4 (sometimes in V 3), then slightly decreases to V 5 -V 6, but T V 6 > T V1.

6.8.4. The direction of the T wave in different leads. In most leads (I, II, aVF, V 2 -V 6) the T wave is positive; in lead aVR, always negative; in III, aVL, V 1 (sometimes V 2) may be slightly positive, negative, or biphasic.

6.9. U wave rarely recorded on the ECG. This is a small (up to 1.0-2.5 mm) positive wave, following after 0.02-0.04 sec or immediately after the T wave. The origin has not been completely elucidated. It is assumed that it reflects the repolarization of the fibers of the conduction system of the heart. More often it is recorded in the right chest leads, less often in the left chest leads, and even less often in the standard leads.

6.10. QRST complex - ventricular complex (electrical ventricular systole). Analysis of the QRST complex involves determining its duration, the value of the systolic index, the ratio of the time of excitation and the time of termination of excitation.

6.10.1. Determination of the duration of the QT interval. The QT interval is measured from the beginning of the Q wave to the end of the T wave (U). Normally, it is 0.32-0.37 s for men, 0.35-0.40 s for women. The duration of the QT interval depends on age and heart rate: the younger the child and the higher the heart rate, the shorter the QT (see Appendix Table 1).

6.10.2. Assessment of the QT interval. The QT interval found on the ECG should be compared with the standard, which is either given in the table (see Appendix Table 1), where it is calculated for each heart rate value (R-R), or can be approximately determined by the Bazett formula: , where K is a coefficient equal to 0 .37 for men; 0.40 for women; 0.41 for children under 6 months of age and 0.38 for children under 12 years of age. If the actual QT interval is more than normal by 0.03 s or more, then this is regarded as a prolongation of the electrical systole of the ventricles. Some authors distinguish two phases in the electrical systole of the heart: the excitation phase (from the beginning of the Q wave to the beginning of the T wave - the Q-T 1 interval) and the recovery phase (from the beginning of the T wave to its end - the T 1 -T interval).

6.10.3. Determination of the systolic index (SP) and its assessment. The systolic index is the ratio of the duration of electrical systole in seconds to total duration cardiac cycle(RR) per second, expressed in %. The SP standard can be determined from the table depending on the heart rate (RR duration) or calculated using the formula: SP \u003d QT / RR x 100%. The joint venture is considered increased if the actual indicator exceeds the standard by 5% or more.

7. Plan (scheme) for decoding the electrocardiogram

Analysis (decoding) of the ECG includes all the positions set forth in the section "Analysis and characteristics of the elements of the electrocardiogram". To better remember the sequence of actions, we present a general scheme.

1. Preparatory stage: familiarization with the data about the child - age, gender, main diagnosis and accompanying illnesses, health group, etc.

2. Checking the standards of ECG registration technique. ECG voltage.

3. A cursory review of the entire tape to obtain preliminary data on the presence of pathological changes.

4. Analysis heart rate:

a. determining the regularity of the heart rhythm,

b. definition of the pacemaker,

c. calculation and evaluation of the number of heartbeats.

5. Analysis and evaluation of conductivity.

6. Determining the position of the electrical axis of the heart.

7. P-wave analysis (atrial complex).

8. Analysis of the ventricular QRST complex:

a. analysis of the QRS complex,

b. S (R)T segment analysis,

c. T wave analysis

d. analysis and evaluation of the QT interval.

9. Electrocardiographic conclusion.

8. Electrocardiographic conclusion

The electrocardiographic conclusion is the most difficult and critical part of the ECG analysis.

In conclusion, it should be noted:

Heart rate source (sinus, non-sinus);

Rhythm regularity (correct, incorrect) and heart rate;

EOS position;

ECG intervals, short description teeth and ECG complexes (in the absence of changes indicate that the elements of the ECG correspond to age norm);

Individual changes ECG elements with an attempt to interpret them in terms of a presumed violation of electrophysiological processes (if there are no changes, this item is omitted).

ECG is a method of very high sensitivity, capturing a wide range of functional and metabolic changes in the body, especially in children, so ECG changes are often non-specific. Identical ECG changes can be observed with various diseases and not just the cardiovascular system. Hence the difficulty of interpreting the found pathological indicators. ECG analysis should be performed after reviewing the patient's history and clinical picture disease, and ECG alone cannot be used to make a clinical diagnosis. When analyzing children's ECGs, small changes are often detected even in apparently healthy children and adolescents. This is due to the processes of growth and differentiation of heart structures. But it's important not to miss early signs current pathological processes myocardium. It should be borne in mind that a normal ECG does not necessarily indicate the absence of changes in the heart and vice versa.

At no pathological changes indicate that an ECG is an option age norm.

ECG with deviations from the norm, should be classified. There are 3 groups.

I group. ECG with changes (syndromes) related to age norm options.

II group. Borderline ECGs. Changes (syndromes) that require mandatory in-depth examination and long-term monitoring in dynamics with ECG monitoring.

cardiac activity. In many patients, a shift in the electrical axis is detected - a shift either to the right or to the left. How to determine its position, what affects the change in the EOS and why is such a pathology dangerous?

Electrocardiography as a method for determining EOS

Electrocardiography is used to record the electrical activity of the heart in cardiology. Result this study displayed in the form of a graphic record and is called an electrocardiogram.

The procedure for taking an electrocardiogram is painless and takes about ten minutes. First, electrodes are applied to the patient, having previously lubricated the skin surface with a conductive gel or by placing gauze pads moistened with saline.

The electrodes are applied in the following sequence:

on the right wrist - red
on left wrist- yellow
on the left ankle - green
on the right ankle - black

Then six chest electrodes are applied in a certain sequence, from the middle of the chest to the left armpit. The electrodes are fixed with a special tape or mounted on suction cups.

The doctor turns on the electrocardiograph, which records the voltage between two electrodes. The electrocardiogram is displayed on thermal paper and reflects the following parameters of the work and condition of the heart:

One of the main electrocardiological indicators is the direction of the electrical line of the heart. This parameter allows you to detect changes in cardiac activity or dysfunction of other organs (lungs, etc.).

Electrical axis of the heart: definition and factors of influence

To determine the electrical line of the heart importance has a conduction system of the heart. This system consists of cardiac conduction muscle fibers, which transmit electrical excitation from one part of the heart to another.

Shift of the electrical axis to the left

The electric axis is strongly deviated to the left if its value is in the range from 0⁰ to -90⁰. This deviation can be caused by the following:

disturbances in the impulse conduction along the left branch of the His fibers (that is, in the left ventricle)
cardiosclerosis (a disease in which connective tissue replaces muscle tissue hearts)
persistent hypertension
heart defects
cardiomyopathy (changes in the heart muscle)
in the myocardium (myocarditis)
non-inflammatory myocardial damage (myocardial dystrophy)
intracardiac calcification and others

Shift of the electrical axis to the right

The EOS value in the range from +90⁰ to +180⁰ indicates a strong deviation of the electrical axis of the heart to the right. The reasons for this change in the position of the axis of the heart can be:

disruption of impulse transmission right branch His fibers (responsible for the transmission of excitation in the right ventricle)
constriction pulmonary artery(stenosis), which prevents the movement of blood from the right ventricle, so inside it
ischemic disease in combination with arterial hypertension(based on coronary disease there is a lack of nutrition of the myocardium)
myocardial infarction (death of myocardial cells of the right ventricle)
diseases of the bronchi and lungs, forming a "cor pulmonale". In this case, the left ventricle does not function fully, there is congestion of the right ventricle
pulmonary embolism, i.e. blockage of the vessel by a thrombus, resulting in a violation of gas exchange in the lungs, narrowing of the vessels of the small blood circle and congestion of the right ventricle
mitral valve stenosis (most often occurs after rheumatism) - fusion of the valve leaflets, preventing the movement of blood from the left atrium, which leads to pulmonary hypertension and increased stress on the right ventricle

The main consequence of all causes is an increased load on the right ventricle. As a result, the walls of the right ventricle occur and the electrical vector of the heart deviates to the right.

The danger of changing the position of the EOS

The study of the direction of the electrical line of the heart is additional, therefore, making a diagnosis only on the basis of the location of the EOS is incorrect. If a patient has an EOS shift beyond the normal range, an comprehensive examination and the cause is identified, only then treatment is prescribed.

Projection of the mean resulting vector QRS to the frontal plane is called middle electric axis heart (AQRS). Rotations of the heart around a conditional anteroposterior axis are accompanied by a deviation of the electrical axis of the heart in the frontal plane and a significant change in the configuration of the complex QRS in standard and enhanced unipolar limb leads.

As shown in fig. 4.10, the position of the electrical axis of the heart in the six-axis Bailey system is quantified by the angle a, which is formed by the electrical axis of the heart and the positive half of the axis of the standard lead. The positive pole of the axis of this lead corresponds to the origin - 0 negative - ±380 Perpendicular drawn from the electrical center of the heart to the horizontal zero line, coincides with the axis of the lead aVF, the positive pole of which corresponds to +90°, and the negative - minus 90 e, the positive pole of the II axis of the standard lead is located at an angle crowbar +60 V, III standard lead - at +120% lead aVL - at an angle of -30°, and leads aVR - at an angle of -150°, etc.

In a healthy person, the electrical axis of the heart is usually located in the sector from 0 ° to + 90 °, only occasionally going beyond these limits. Normally, the electrical axis of the heart approximately corresponds to the orientation of its anatomical axis. For example, the horizontal position of the electrical axis of the heart (angle a from 0° to 29°) is often found in healthy people with a hypersthenic body type, and vertical position electric axis - in persons with a vertically located heart.

More significant rotations of the electrical axis of the heart around the anteroposterior axis both to the right (more than +9 (G) and to the left (less than 0 °), as a rule, are due to pathological changes in the heart muscle - ventricular myocardial hypertrophy or intraventricular conduction disturbances (see However, it should be remembered that with moderate pathological changes in the heart, the position of the electrical axis of the heart may not differ from that in healthy people, i.e., it may be horizontal, vertical, or even normal.

Let us consider two methods for determining the position of the electrical axis of the heart.

Determination of the angle a by a graphical method. To accurately determine the position of the electrical axis of the heart by a graphical method, it is sufficient to calculate the algebraic sum of the amplitudes of the teeth of the complex QRS in any two leads from the limbs, the axes of which are located in the frontal plane. Usually, I and III standard leads are used for this purpose (Fig. 4.11). Positive or negative value of an algebraic sum

teeth QRS on an arbitrarily chosen scale is plotted on the positive or negative part of the axis of the corresponding lead in the six-axis Bailey coordinate system.

For example, in the ECG shown in Fig. 4.11, the algebraic sum of the teeth of the complex QRS in I standard lead is + 12 mm (R== 12 mm, Q= 0 mm S= Oh mm). This value is laid on the positive part of the abduction axis I. The sum of the teeth in standard lead III is -12 mm (R= + 3 mm, S=- 15 mm); it is postponed to the negative part of this lead.

These quantities (corresponding to the algebraic sum of the amplitudes of the teeth) actually represent projections of the desired electrical axis of the heart on axes I and III of standard leads. From the ends of these projections restore perpendiculars to the axes of the leads. The intersection point of the perpendiculars is connected to the center of the system. This line is the electrical axis of the heart. (AQRS). In this case, the angle a is -30 e (a sharp deviation to the left of the electrical axis of the heart).

The angle a can also be determined after calculating the algebraic sums of the amplitudes of the teeth of the complex QRSb two limb leads according to various tables and diagrams given in electrocardiography manuals.

Visual determination of the angle a. The graphical method described above for determining the position of the electrical axis of the heart, although it is the most accurate, is rarely used in clinical electrocardiography in practice. A simpler and more accessible method is the visual method for determining the position of the electrical axis of the heart, which makes it possible to quickly estimate the angle a with an accuracy of ±10°. The method is based on two well known principles.

1. The maximum positive or negative value of the algebraic sum of the teeth of the complex QRS is observed in that electrocardiographic lead, the axis of which approximately coincides with the location of the electrical leu of the heart and is parallel to it.

2. Complex type RS, where the algebraic sum of the teeth is zero (R = S or I = Q+ S), is recorded in the lead whose axis is perpendicular to the electrical axis of the heart.

For example, let's try to determine the position of the electrical axis of the heart by a visual method using the ECG shown in Fig. 4.12. Maximum algebraic sum of complex teeth QRS and the highest tooth R are observed in standard lead II, and a complex like RS(R*S)- in lead aVL. This indicates that the electrical axis of the heart is located at an angle a of about 60° (coinciding with the axis II of the standard lead and perpendicular to the axis of lead aVL). This is also confirmed by the approximate equality of the amplitude of the teeth R in leads I and III, the axes of which in this case are located at some identical (!) angle to the electrical axis of the heart (R ] l > R t ~ R ul). Thus, on the ECG there is a normal position of the electrical axis of the heart (angle a = 60°).

Let us consider one more variant of the normal position of the electrical axis of the heart (the angle A= 45°) shown on rice. 4.13.a. In this case, the electrical axis of the heart is located between the axes of leads II and aVR. Max Prong R will be registered in the same way as in the previous example, in lead II, and

/?,>/?,> Rul*. In this case, the electrical axis is perpendicular to the hypothetical line, which, as it were, passes between the axes of III of the standard lead and lead aVL. Under certain assumptions, it can be assumed that the axes of lead III and aVL are almost perpendicular to the electrical axis of the heart. Therefore, it is in these leads that the algebraic sum of the teeth approaches zero, and the complexes themselves QRS take the form RS, where are the teeth /? w and i? aVL have a minimum amplitude only slightly exceeding the amplitude of the corresponding Sj n teeth and S sVL .

At vertical position of the electrical axis of the heart (Fig. 4.13, b), when the angle a is about + 90 °, the maximum algebraic sum of the teeth of the complex QRSn maximum positive tooth R will be detected in lead aVF, the axis of which coincides with the direction of the electrical axis of the heart. Complex type RS, Where R-S, is recorded in the I standard lead, the axis of which is perpendicular to the direction of the electrical axis of the heart. Lead aVL is dominated by a negative wave S , and in lead III - a positive tooth R.

With an even more pronounced turn of the electrical axis of the heart to the right, for example, if the angle a is +120°, as shown in Fig. 4.13, in, max prong R is recorded in standard lead III In lead aVR, a lump is recorded

plex QR, Where R= Q. Lead II and aVF are dominated by positive waves R, and in lead I and aVL - deep negative teeth S.

On the contrary, when horizontal position of the electrical axis of the heart, (angle a from + 30 ° to 0 °) maximum tooth R will be fixed in the I standard lead (Fig. 4.14, a), and the type complex RS- in lead aVF. A recessed wave is recorded in lead III Sy and in lead aVL - a high tooth R.R [ > R ll > R lli< S uy

With a significant deviation of the electrical axis of the heart to the left (angle a - -30), as shown in Fig. 4.14, b, maximum positive tooth R shifts to lead aVL, and the complex QRSuxcm RS- into lead II. high prong R also fixed in lead I, and deep negative teeth predominate in leads III and aVF S. R x > R li > R m .

So for practical definition position of the electrical axis of the heart, we will further use the visual method for determining the angle a. We suggest that you independently perform several tasks to determine the position of the electrical axis of the heart visually (see Fig. 4.16-4.19). In this case, it is advisable to use a pre-prepared scheme of a six-axis coordinate system (see Fig. 2.6), as well as the following algorithm.

Algorithm for determining the position of the electrical axis of the heart in the frontal plane

1. Find one or two leads in which QRS approaching zero ( R S or R* Q+ L). The axis of this assignment is almost perpendicular to the desired direction of the electrical axis of the heart.

2 Find one or two leads in which the algebraic sum of the teeth of the complex QRS has a maximum positive value. The axis of this lead approximately coincides with the direction of the electrical axis of the heart.

3. Adjust the two results. Determine angle a.

An example of using this algorithm is shown in fig. 4.15. When analyzing the ECG in 6 leads from the limbs shown in Fig. 4.15, the normal position is approximately determined

electrical axis of the heart R H = A, > L,. The algebraic sum of the teeth of the complex (DO "is equal to zero in lead III (R= 5). Therefore, the electrical axis is presumably located at an angle a + 30° to the horizontal, coinciding with the axis aVR . Algebraic sum of teeth QRS has a maximum value in leads I and II, and A, - Rxv This confirms the assumption made about the value of the angle a (+30°), since identical projections on the lead axes (equal teeth R, and /?,) are possible only with such an arrangement of the electrical axis of the heart.

Conclusion. Normal position of the electrical axis of the heart. Angle a - +30°.

And now, using the algorithm, independently determine the position of the electrical axis of the heart on the ECG, shown in Fig. 4.16-4.19.

Check if your solution is correct.

Samples of correct answers

Rice. 4.16, a. Analysis of the ratios of the teeth of the complex QRSw presented ECG suggests that there is a normal position of the electrical axis of the heart (R il > R l > R m). Indeed, the sum of the teeth of the complex QRS is zero in lead aVL (R ~ S). Therefore, the electrical axis of the heart is presumably located at an angle of +60° to the horizontal and coincides with the axis II of the standard lead. The algebraic sum of the teeth of the complex QRS has a maximum value in the II standard lead. This confirms the above assumption about the value of the angle a + 60". Conclusion. Normal position of the electrical axis of the heart Angle a+60°.

Rice. 4.16b. On the ECG there is a deviation of the electrical axis of the heart to the left: high teeth R recorded in leads I and aVL, deep teeth S- in leads III and aVF, with i ^> R II > i ^ II.

The algebraic sum of the amplitudes of the teeth of the complex QRS is equal to zero in standard lead II. Therefore, the electrical axis of the heart is perpendicular to the axis of lead II, that is, it is located at an angle a = -30 °. Maximum positive value sum of teeth QRS is detected in lead aVL, which confirms the above assumption. Conclusion. Deviation of the electrical axis of the heart to the left. Angle a--30 e.

Rice. 4.17, a. On the ECG there is a deviation of the electrical axis of the heart to the right: high teeth Rm mVF and deep teeth 5, aVU and R in > R u > R l . The algebraic sum of the amplitudes of the teeth of the complex QRS equals zero in lead aVR. The electrical axis of the heart is located at an angle of a + 120 e and approximately coincides with the axis III of the standard lead. This is confirmed by the fact that the maximum amplitude of the tooth R determined in lead Sh.

Conclusion, Deviation of the electrical axis of the heart to the right. Angle a= +120*.

Rice. 4.17b. On the ECG, high teeth Lsh aVF and relatively deep teeth L" aVL were registered, and ^ P>^ G>L^. The sum of the amplitudes of QRS equals zero in lead I. The electrical axis of the heart is located at an angle a = +90°, coinciding with the axis of lead aVR In lead aVF, there is a maximum positive sum of wave amplitudes QRS, which confirms this assumption. Conclusion. Vertical position of the electrical axis of the heart. Angle a - +90°.

Rice. 4.18, a. The ECG recorded high teeth /?, hVL and deep teeth L* H1 oVF, and /?,>/?,>/?,. In lead aVR, the algebraic sum of the teeth of the complex QRS equal to a bullet. The electrical axis of the heart, most likely, coincides with the negative half of the axis of standard lead III (the largest amplitude S U 1). Unlike an ECG, the

noah in fig. 4.17, a, the electrical axis of the heart is not deviated to the right, but

to the left, so angle a is approximately -60°. Conclusion. A sharp deviation of the electrical axis of the heart to the left. Angle a -60 e.

Rice. 4.18, 6. Approximately there is a turn of the axis of the heart to the left: high teeth I g aVL, deep teeth Sul aVF , and R J > R ll > R tll . There is no lead on the ECG in which the algebraic sum of the teeth QRS is clearly equal to zero. However, the minimum algebraic sum of the teeth QRS, approaching zero, found in leads II and aVF , whose axes are located side by side, at an angle of 30* to each other. Moreover, the sum of the amplitudes of the teeth of the complex QRS in standard lead II it has a small positive value, and in lead aVF it has a small negative value. Therefore, a hypothetical line perpendicular to the electrical axis of the heart passes between the axes of leads II and aVF, and the electrical axis of the heart, respectively, is approximately at an angle a equal to - 15 °, i.e., between the axes of leads I and aVL. Indeed, the maximum algebraic sum of teeth QRS found in leads I and aVL, which confirms the above assumption. Conclusion. Deviation of the electrical axis of the heart to the left. Angle a * - 15 e.

Rice. 4.19 A. Approximately there is a turn of the electrical axis of the heart to the left: high teeth D, aVL, relatively deep tooth S uv at what R t > R n > R m . As in the previous example, the ECG cannot reveal a lead in which the algebraic sum of the teeth QRS equals zero. A hypothetical line perpendicular to the electrical axis of the heart probably passes between adjacent lead axes III and aVF , since the algebraic sum of the teeth QRS in these leads approaches zero, and the sum of the teeth in III abduction indicates the predominance of a negative tooth S , and in lead aVF - on the predominance of the tooth R. Therefore, the electrical axis of the heart is most likely located at an angle a* +15°. Maximum positive algebraic sum of teeth QRS is detected in lead I, which confirms the above assumption. Conclusion. Horizontal position of the electrical axis of the heart. Angle a +15°.

Rice. 4.19 b. Approximately has a turn of the electrical axis of the heart to the left: high teeth Rlt aVL , deep teeth 5 Sh, aVF , moreover R l > R ^> R Bl . In lead aVF, the algebraic sum of the teeth QRS is equal to zero, i.e., the electrical axis is perpendicular to the axis of assignment aVF. Therefore, we can assume that the angle a is 0°. The maximum positive sum of the teeth is found in the I standard lead, which confirms the above assumption. Conclusion. Horizontal position of the electrical axis of the heart. Angle a i 0°.

The electrical axis of the heart (EOS) is a common concept among cardiologists and specialists in checking the functionality of the heart. It shows the electrical processes occurring in the body.

Cardiologists represent an organ in three dimensions, superimposing it on the coordinate axis, which is conventionally taken as chest. This makes it possible to set the angle of inclination of the axis. The angle of the axis may be different.

For example, EOS is deflected to the right. It can be tilted to the left, as well as take a position horizontally or vertically. Changes of the bioelectrical character, accompanying the next compression and unclenching, are reflected in the slope of the vector.

In the event of cardiovascular pathologies, the electrical axis of the heart can change its position

The mechanism that transmits these impulses is the muscle filamentous fibers. They start shrinking sinus node receiving a signal from nerve center brain.

Therefore, they say during the examination: the heart muscle is normal, there is sinus rhythm. The person is healthy.

Impulse oscillation, moving through the system, reaches the heart organ, causing it to contract. When deviations occur, the EOS changes its location.

The ventricle of the organ on the left is much more voluminous in terms of the size of the department on the right. There are stronger impulses. Therefore, the axis deviates more towards him.

Deviation of the axis of the heart

Transferring the projection of the heart muscle to an imaginary coordinate system, it is assumed that the axis has an angle of deviation from 0 to + 90 degrees for healthy people. Thin and tall people (asthenic type) have an angle of +70 to +90 degrees.

Small people, strong physique (hypersthenic type) have an angle, deviations from 0 to + 30 degrees. Clean look These types of people are rare in nature.

People from mixed type physiques have EOS with a semi-vertical or semi-horizontal position. There are five positions of EOS:

She's fine
Positioned horizontally
Placed in a semi-horizontal position
Vertical state
Location semi-vertical

All conditions are not diseases.

Pathological shift to the left

The electrical axis of the heart can deviate to the left with a deep breath

Pathologies are not observed, but the EOS may deviate to the left in the following situations:

When a man takes a deep breath
When the body is horizontal. The diaphragm is under pressure from internal organs
With a high aperture in small people

To the right, the EOS is shifted without the presence of obvious pathologies in the following cases:

When the deep breath ends
When the human body is in a vertical position
Tall thin people

These shifts from normal state are not considered a disease. These are the prerequisites for the onset of destruction in the heart organ and the conduction apparatus, indicating possible developing diseases:

Wall thickening.
Interruptions of the working valve of the ventricle on the left.
Violation of the conduction of electrical signals of the left ventricle.

Early diseases:

congenital
Acquired heart disease
Flickering
Infectious myocardial injury

Pathology in the right position

Based on the ECG, cardiologists can determine the nature of the disease by the position of the electrical axis of the heart.

The heart organ is regulated by impulses sent by the brain along the nerve fibers. They force the muscles of the organ to contract periodically. Any disturbance of nerve impulses leads to changes in the organs.

The heart is no exception in this case. EOS normally occupies a diagonal location - directed down and to the left. Based on these provisions, reflected in, specialists can determine the nature of the disease.

For each person, the location of the axis depends on the physique and personality.

How you can independently decipher the results of the ECG, see the following video:

When it rolls to the right, it is considered normal in newly born children. In adults, this is considered an indicator of a serious illness.

For example, right ventricular hypertrophy. It may occur for the following reasons:

Diseases of the pulmonary system and bronchi: prolonged bronchial asthma.
Chronical bronchitis, obstructive bronchitis, emphysema.
with a change in the ventricular valve on the right.
The stronger the thickening of the walls of the right section, the greater the angle of inclination in this direction.

The roll of the axis to the right indicates such diseases as:

Myocardial circulatory disorders. Oxygen starvation. When in coronary arteries impassability increases sharply. There is a risk of myocardial infarction.
pulmonary artery, is congenital, acquired. This is a decrease in the clearance lung vessel when the exit of the blood flow from the heart on the right is difficult. Against this background, thickening of the walls and an increase in the right section develops.
Atrial fibrillation. In the atrium, a violation of electrical processes occurs, which is accompanied by a blockage or rupture of the cerebral vessel.
. The efficiency of the lungs is disturbed, pathological changes occur, difficulties arise in the functioning of the heart section on the left. Therefore, the other department is forced to work with double strength, and this is the way to thicken the walls of the organ.
A defect or defect in the membranous tissue at the border of the atria. This is due to the existing hole in the septum between the atria, when blood is thrown from the left atrium to the right, which is excluded. Heart failure occurs, blood pressure increases in the arteries of the lung.
Mitral valve stenosis. This is a decrease in the internal diameter of the channel between the atrium on the left side and the heart. This impedes the movement of the blood flow and the rhythmic work fails. cardiac organ. Considered an acquired defect.
Pulmonary embolism. When thrombotic clots form in the vessels of the artery. They, moving along the bloodstream, block the artery of the lung and branches.
Primary pulmonary hypertension. Increased pressure in the arteries of the lung for various reasons.
Poisoning by certain antidepressants.

Symptoms of pathologies

Sudden seizures suffocation may indicate a deviation of the EOS, which means the occurrence of cardiovascular pathology

It is necessary to think seriously when the following symptoms occur:

Diagnosis of lesions of the cardiovascular system

If two or three symptoms are detected, it is necessary to undergo an examination.

To do this, the cardiologist prescribes special methods studies to determine existing diseases:

for a detailed examination of the anatomy of the organ.
. These are special sensors and a recording device that are attached to the patient's body. He can lead usual image life for a certain time. Usually it is from 1 to 7 days. Sometimes the patient is asked to perform several exercise to determine the response of the heart muscle to exercise.
Chest X-ray.
Removal of the cardiogram under load.
Coronary angiography is a procedure to detect the condition of the coronary vessels.

Treatment

To support the heart when a deviation of the EOS is detected, alternative therapy methods can be used

When deviations of the EOS are detected, existing diseases are identified and treatment is prescribed, depending on many factors of the state of the body. After the treatment, as a rule, the axis returns to its normal position.

Further treatment is reduced to the prevention and maintenance of the body in a stable state, preventing deterioration. In the treatment of hypertrophy of both ventricles, verampil and drugs are prescribed.

not ruled out surgical intervention when the affected part of the organ is removed.

Additionally apply folk recipes to restore and support the heart muscle:

Apply a decoction of the following composition: take cudweed and wild rosemary in 2 parts; 3 parts - motherwort herbs; 1 part kidney tea, mix everything. Pour a heaping tablespoon of the mixture cold water in a volume of one and a half glasses, bring to a boil, let it boil for 5 minutes. Infusion wrap and insist for 4 hours. Pass through gauze. Drink a warm decoction of half a glass strictly 20-30 minutes before meals three times a day.
Taking cranberries with sugar after eating a teaspoon has a very beneficial effect.
St. John's wort decoction. Dry grass in the amount of 100 g pour two liters cold water. Boil and keep on fire for 10 minutes. Remove, wrap and let it brew for about an hour. Filter, dissolve 200 ml of honey. Store in a glass container. Take before meals for half an hour, 3 tablespoons no more than three times.
Garlic. Grind garlic cloves with a blender, add honey in a ratio of 1: 1. Leave for 7 days in a dark place, shaking constantly. Take a tablespoon three times before meals. Drink throughout the year, taking breaks for 7 days every 30 days. Tincture helps with hypertension, atherosclerosis and left ventricular hypertrophy.
If there is shortness of breath, nettle will help in fresh. Wash and chop the young stems and leaves of the plant. Take 5 tablespoons of raw materials, in glass jar mix with 5 tbsp. l. honey. Put in a place not in the light, shaking daily. After 14 days, heat the product for a couple. When the medicine becomes liquid, strain through cheesecloth and keep in a cool place. Take 1 tsp. 3 times a day before meals.

The human heart works without stopping and requires a careful attitude towards itself. It is necessary to consult and conduct examinations constantly, to be treated and to observe preventive measures. Then the heart and the whole body will work as a well-oiled mechanism.