The horizontal axis of the heart causes. Deviation of the electrical axis of the heart to the right #8212; what does it mean. ECG interference

This article presents modern views for ECG diagnostics in pediatrics. The team of authors examined some of the most characteristic changes that distinguish the ECG in childhood.

A normal ECG in children differs from ECG of adults and has a number of specific features in each age period. The most pronounced differences are observed in children early age, and after 12 years, the child’s ECG approaches the adult’s cardiogram.

Peculiarities heart rate in children

Childhood is characterized by a high heart rate (HR); newborns have the highest heart rate; as the child grows, it decreases. Children exhibit pronounced lability of heart rate; permissible fluctuations are 15–20% of the average age value. Sinus respiratory arrhythmia is often observed, the degree sinus arrhythmia can be determined using Table 1.

The main pacemaker is the sinus node, however, acceptable variants of the age norm include the mid-atrial rhythm, as well as migration of the pacemaker through the atria.

Features of the duration of ECG intervals in childhood

Considering that children have a higher heart rate than adults, the duration of ECG intervals, waves and complexes decreases.

Changing the voltage of the QRS complex waves

The amplitude of the ECG waves depends on the individual characteristics of the child: tissue electrical conductivity, chest thickness, heart size, etc. In the first 5–10 days of life, a low voltage of the QRS complex waves is noted, which indicates reduced electrical activity of the myocardium. Subsequently, the amplitude of these waves increases. From infancy to 8 years, a higher amplitude of the waves is detected, especially in the chest leads, this is due to the smaller thickness of the chest, large sizes heart relative to the chest and rotations of the heart around its axes, as well as a greater degree of fit of the heart to the chest.

Features of the position of the electrical axis of the heart

In newborns and children in the first months of life, there is a significant deviation of the electrical axis of the heart (EOS) to the right (from 90 to 180°, on average 150°). From the age of 3 months. By the age of 1 year, in most children, the EOS moves to a vertical position (75–90°), but significant fluctuations in the angle  are still allowed (from 30 to 120°). By 2 years, 2/3 of children still maintain the vertical position of the EOS, and 1/3 have a normal position (30–70°). In preschoolers and schoolchildren, as well as in adults, it is predominant normal position EOS, but variants in the form of a vertical (more often) and horizontal (less often) position may be noted.

Such features of the position of the EOS in children are associated with changes in the ratio of masses and electrical activity of the right and left ventricles of the heart, as well as with changes in the position of the heart in the chest (rotations around its axes). In children in the first months of life, anatomical and electrophysiological predominance of the right ventricle is noted. With age, as the mass of the left ventricle increases rapidly and the heart rotates with a decrease in the degree of adhesion of the right ventricle to the surface of the chest, the position of the EOS moves from the right to the normogram. The changes that are occurring can be judged by the changing ratio of the amplitude of the R and S waves in the standard and chest leads on the ECG, as well as by the displacement of the transition zone. Thus, as children grow in standard leads, the amplitude of the R wave in lead I increases, and in lead III it decreases; the amplitude of the S wave, on the contrary, decreases in lead I and increases in lead III. In the chest leads, with age, the amplitude of the R waves in the left chest leads (V4-V6) increases and decreases in leads V1, V2; the depth of the S waves increases in the right chest leads and decreases in the left ones; The transition zone gradually shifts from V5 in newborns to V3, V2 after the 1st year. All this, as well as an increase in the interval of internal deviation in lead V6, reflects an increase in electrical activity left ventricle and rotation of the heart around its axes.

In newborn children, large differences are revealed: the electrical axes of the P and T vectors are located practically in the same sector as in adults, but with a slight shift to the right: the direction of the P vector is on average 55°, the T vector is on average 70°, while the QRS vector is sharply deviated to the right (on average 150°). The value of the adjacent angle between the electrical axes P and QRS, T and QRS reaches a maximum of 80–100°. This partly explains the differences in the size and direction of the P waves, and especially the T waves, as well as the QRS complex in newborns.

With age, the value of the adjacent angle between the electrical axes of the P and QRS, T and QRS vectors decreases significantly: in the first 3 months. life on average up to 40–50°, in young children – up to 30°, and in preschool age it reaches 10–30°, as in schoolchildren and adults (Fig. 1).

In adults and children school age the position of the electrical axes of the total vectors of the atria (vector P) and ventricular repolarization (vector T) relative to the ventricular vector (vector QRS) is in the same sector from 0 to 90°, and the direction of the electrical axis of the vectors P (on average 45–50°) and T (on average 30–40°) does not differ sharply from the orientation of the EOS (QRS vector on average 60–70°). An adjacent angle of only 10–30° is formed between the electrical axes of the P and QRS, T and QRS vectors. This position of the listed vectors explains the same (positive) direction of the P and T waves with the R wave in most leads on the ECG.

Features of teeth intervals and complexes of children's ECG

Atrial complex (P wave). In children, as in adults, the P wave is small (0.5–2.5 mm), with maximum amplitude in standard leads I and II. In most leads it is positive (I, II, aVF, V2-V6), in lead aVR it is always negative, in leads III, aVL, V1 it can be smoothed, biphasic or negative. In children, a slightly negative P wave in lead V2 is also allowed.

Greatest Features P waves are observed in newborns, which is explained by increased electrical activity of the atria due to the conditions of intrauterine circulation and its postnatal restructuring. In newborns, the P wave in standard leads, compared to the size of the R wave, is relatively high (but in amplitude no more than 2.5 mm), pointed, and sometimes may have a small notch at the apex as a result of non-simultaneous coverage of the right and left atria by excitation (but not more than 0 .02–0.03 s). As the child grows, the amplitude of the P wave decreases slightly. With age, the ratio of the size of the P and R waves in standard leads also changes. In newborns it is 1: 3, 1: 4; as the amplitude of the R wave increases and the amplitude of the P wave decreases, this ratio by 1–2 years decreases to 1: 6, and after 2 years it becomes the same as in adults: 1: 8; 1:10. Than smaller child, the shorter the duration of the P wave. It increases on average from 0.05 s in newborns to 0.09 s in older children and adults.

Features of the PQ interval in children. The duration of the PQ interval depends on heart rate and age. As children grow, there is a noticeable increase in the duration of the PQ interval: on average from 0.10 s (no more than 0.13 s) in newborns to 0.14 s (no more than 0.18 s) in adolescents and 0.16 s in adults (no more than 0.20 s).

Features of the QRS complex in children. In children, the time of ventricular excitation coverage (QRS interval) increases with age: on average from 0.045 s in newborns to 0.07–0.08 s in older children and adults.

In children, as in adults, the Q wave is recorded inconsistently, more often in II, III, aVF, left chest leads (V4-V6), less often in I and aVL leads. In lead aVR, a deep and wide Q wave of the Qr type or QS complex is detected. In the right chest leads, Q waves, as a rule, are not recorded. In young children, the Q wave in standard leads I and II is often absent or weakly expressed, and in children of the first 3 months. – also in V5, V6. Thus, the frequency of registration of the Q wave in various leads increases with the age of the child.

In standard lead III in all age groups, the Q wave is also small on average (2 mm), but can be deep and reach up to 5 mm in newborns and infants; in early and preschool age - up to 7–9 mm and only in schoolchildren it begins to decrease, reaching a maximum of 5 mm. Sometimes, in healthy adults, a deep Q wave is recorded in standard lead III (up to 4–7 mm). In all age groups of children, the size of the Q wave in this lead can exceed 1/4 of the size of the R wave.

In lead aVR, the Q wave has maximum depth, which increases with the age of the child: from 1.5–2 mm in newborns to 5 mm on average (with a maximum of 7–8 mm) in infants and at an early age, to 7 mm on average (with a maximum of 11 mm) in preschoolers and up to 8 mm on average (with a maximum of 14 mm) in schoolchildren. The duration of the Q wave should not exceed 0.02–0.03 s.

In children, as well as in adults, R waves are usually recorded in all leads, only in aVR they can be small or absent (sometimes in lead V1). There are significant fluctuations in the amplitude of the R waves in different leads from 1–2 to 15 mm, but the maximum value of the R waves in standard leads is up to 20 mm, and in the chest leads up to 25 mm. The smallest magnitude of R waves is observed in newborns, especially in the strengthened unipolar and chest leads. However, even in newborns, the amplitude of the R wave in standard lead III is quite large, since the electrical axis of the heart is deviated to the right. After 1 month the amplitude of the RIII wave decreases, the size of the R waves in the remaining leads gradually increases, especially noticeably in the II and I standard and in the left (V4-V6) chest leads, reaching a maximum at school age.

In the normal position of the EOS, high R waves with a maximum of RII are recorded in all limb leads (except aVR). In the chest leads, the amplitude of the R waves increases from left to right from V1 (r wave) to V4 with a maximum of RV4, then decreases slightly, but the R waves in the left chest leads are higher than in the right ones. Normally, in lead V1, the R wave may be absent, and then a QS-type complex is recorded. In children, the QS type complex is also rarely allowed in leads V2, V3.

In newborns, electrical alternans is allowed - fluctuations in the height of the R waves in the same lead. Variants of the age norm also include respiratory alternation of ECG waves.

In children, deformation of the QRS complex in the form of the letters “M” or “W” in the III standard and V1 leads is often found in all age groups, starting from the neonatal period. In this case, the duration of the QRS complex does not exceed age norm. Splitting of the QRS complex in healthy children in V1 is referred to as “slow excitation syndrome of the right supraventricular crest” or “incomplete block of the right bundle branch.” The origin of this phenomenon is associated with the excitation of the hypertrophied right “supraventricular scallop” located in the region of the conus pulmonary of the right ventricle, which is the last to be excited. The position of the heart in the chest and the electrical activity of the right and left ventricles changing with age are also important.

The internal deviation interval (time of activation of the right and left ventricles) in children changes as follows. The activation time of the left ventricle (V6) increases from 0.025 s in newborns to 0.045 s in schoolchildren, reflecting an accelerated increase in the mass of the left ventricle. The activation time of the right ventricle (V1) remains virtually unchanged with the child’s age, amounting to 0.02–0.03 s.

In young children, a change in the localization of the transition zone occurs due to a change in the position of the heart in the chest and a change in the electrical activity of the right and left ventricles. In newborns, the transition zone is located in lead V5, which characterizes the dominance of the electrical activity of the right ventricle. At the age of 1 month. the transition zone shifts to leads V3, V4, and after 1 year it is localized in the same place as in older children and adults - in V3 with fluctuations V2-V4. Together with an increase in the amplitude of the R waves and deepening of the S waves in the corresponding leads and an increase in the activation time of the left ventricle, this reflects an increase in the electrical activity of the left ventricle.

Both in adults and in children, the amplitude of the S waves in different leads varies widely: from absence in a few leads to a maximum of 15–16 mm, depending on the position of the EOS. The amplitude of the S waves changes with the age of the child. Newborn children have the smallest depth of S waves in all leads (from 0 to 3 mm), except standard I, where the S wave is quite deep (on average 7 mm, maximum up to 13 mm).

In children older than 1 month. the depth of the S wave in the first standard lead decreases and subsequently in all leads from the limbs (except aVR) S waves of small amplitude (from 0 to 4 mm) are recorded, just like in adults. In healthy children, in leads I, II, III, aVL and aVF, the R waves are usually larger than the S waves. As the child grows, there is a deepening of the S waves in the chest leads V1-V4 and in lead aVR, reaching a maximum value at high school age. In the left chest leads V5-V6, on the contrary, the amplitude of the S waves decreases, often they are not recorded at all. In the chest leads, the depth of the S waves decreases from left to right from V1 to V4, having the greatest depth in leads V1 and V2.

Sometimes in healthy children with an asthenic physique, with the so-called. “hanging heart”, S-type ECG is recorded. In this case, the S waves in all standard (SI, SII, SIII) and chest leads are equal to or exceed the R waves with reduced amplitude. It is believed that this is due to the rotation of the heart around the transverse axis with the apex posteriorly and around the longitudinal axis with the right ventricle forward. In this case, it is almost impossible to determine the angle α, so it is not determined. If the S waves are shallow and there is no shift of the transition zone to the left, then we can assume that this is a normal variant; more often, the S-type ECG is determined by pathology.

The ST segment in children, as well as in adults, should be on the isoline. The ST segment may shift up and down up to 1 mm in the limb leads and up to 1.5–2 mm in the chest leads, especially in the right ones. These shifts do not mean pathology if there are no other changes on the ECG. In newborns, the ST segment is often not expressed and the S wave, when reaching the isoline, immediately turns into a gently rising T wave.

In older children, as in adults, the T waves are positive in most leads (standard I, II, aVF, V4-V6). In standard III and aVL leads, T waves can be smoothed, biphasic or negative; in the right chest leads (V1-V3) are often negative or smoothed; in lead aVR – always negative.

The greatest differences in T waves are observed in newborns. In their standard leads, the T waves are low-amplitude (from 0.5 to 1.5–2 mm) or smoothed. In a number of leads, where T waves in children of other age groups and adults are normally positive, in newborns they are negative, and vice versa. Thus, in newborns there may be negative T waves in standard I, II, in strengthened unipolar and in the left chest leads; may be positive in standard III and right chest leads. By 2–4 weeks. life, an inversion of T waves occurs, i.e. in the I, II standard, aVF and left chest leads (except V4) they become positive, in the right chest and V4 - negative, in the III standard and aVL they can be smoothed, biphasic or negative.

In subsequent years, negative T waves persist in lead V4 until 5–11 years, in lead V3 – up to 10–15 years, in lead V2 – up to 12–16 years, although in leads V1 and V2 negative T waves are allowed in some cases and in healthy adults.

After 1 month During life, the amplitude of T waves gradually increases, amounting in young children from 1 to 5 mm in standard leads and from 1 to 8 mm in chest leads. In schoolchildren, the size of T waves reaches the level of adults and ranges from 1 to 7 mm in standard leads and from 1 to 12–15 mm in chest leads. The T wave is largest in lead V4, sometimes in V3, and in leads V5, V6 its amplitude decreases.

The QT interval (ventricular electrical systole) makes it possible to evaluate functional state myocardium. The following features of electrical systole in children can be identified, reflecting the electrophysiological properties of the myocardium changing with age.

The duration of the QT interval increases as the child grows from 0.24–0.27 s in newborns to 0.33–0.4 s in older children and adults. With age, the relationship between the duration of electrical systole and the duration of cardiac cycle, which reflects the systolic indicator (SP). In newborn children, the duration of electrical systole occupies more than half (SP = 55–60%) of the duration of the cardiac cycle, and in older children and adults – 1/3 or slightly more (37–44%), i.e., with age, SP decreases.

With age, the ratio of the duration of the electrical systole phases changes: the excitation phase (from the beginning of the Q wave to the beginning of the T wave) and the recovery phase, i.e., rapid repolarization (duration of the T wave). In newborns recovery processes in the myocardium, more time is spent than on the excitation phase. In young children, these phases take approximately the same time. In 2/3 of preschoolers and most schoolchildren, as well as in adults, more time is spent on the arousal phase.

Features of ECG in different age periods childhood

Newborn period (Fig. 2).

1. In the first 7–10 days of life, there is a tendency towards tachycardia (heart rate 100–120 beats/min), followed by an increase in heart rate to 120–160 beats/min. Pronounced heart rate lability with large individual fluctuations.
2. A decrease in the voltage of the QRS complex waves in the first 5–10 days of life with a subsequent increase in their amplitude.
3. Deviation of the electrical axis of the heart to the right (angle α 90–170°).
4. The P wave is relatively larger (2.5–3 mm) in comparison with the teeth of the QRS complex (P/R ratio 1: 3, 1: 4), often pointed.
5. PQ interval does not exceed 0.13 s.
6. The Q wave is unstable, as a rule, absent in standard I and in the right chest leads (V1-V3), it can be deep up to 5 mm in standard III and aVF leads.
7. The R wave in standard lead I is low, and in standard lead III it is high, with RIII > RII > RI, high R waves in aVF and right precordial leads. The S wave is deep in standard I, II, aVL and in the left precordial leads. The above reflects the deviation of the EOS to the right.
8. Low amplitude or smoothness of T waves in the limb leads is noted. In the first 7–14 days, the T waves are positive in the right chest leads, and in the I and left chest leads they are negative. By 2–4 weeks. life, an inversion of the T waves occurs, i.e. in the I standard and left pectorals they become positive, and in the right pectorals and V4 they become negative, remaining so in the future until school age.

Infant age: 1 month. – 1 year (Fig. 3).

1. Heart rate decreases slightly (on average 120–130 beats/min) while maintaining rhythm lability.
2. The voltage of the QRS complex teeth increases, often higher than in older children and adults, due to the smaller thickness of the chest.
3. In most infants, the EOS goes into a vertical position, some children have a normogram, but significant fluctuations in the α angle are still allowed (from 30 to 120°).
4. The P wave is clearly expressed in standard leads I and II, and the ratio of the amplitude of the P and R waves decreases to 1: 6 due to an increase in the height of the R wave.
5. The duration of the PQ interval does not exceed 0.13 s.
6. The Q wave is recorded inconsistently and is often absent in the right precordial leads. Its depth increases in standard III and aVF leads (up to 7 mm).
7. The amplitude of the R waves in standard I, II and in the left thoracic (V4-V6) leads increases, and in standard III it decreases. The depth of the S waves decreases in standard I and in the left chest leads and increases in the right chest leads (V1-V3). However, in VI, the amplitude of the R wave, as a rule, still prevails over the magnitude of the S wave. Listed changes reflect the shift of the EOS from the legal form to the vertical position.
8. The amplitude of the T waves increases, and by the end of the 1st year the ratio of the T and R waves is 1: 3, 1: 4.

ECG in young children: 1–3 years (Fig. 4).

1. Heart rate decreases to an average of 110–120 beats/min, and in some children sinus arrhythmia appears.
3. EOS position: 2/3 of children maintain a vertical position, and 1/3 have a normogram.
4. The ratio of the amplitude of the P and R waves in standard leads I, II decreases to 1: 6, 1: 8 due to the increase in the R wave, and after 2 years it becomes the same as in adults (1: 8, 1: 10) .
5. The duration of the PQ interval does not exceed 0.14 s.
6. Q waves are often shallow, but in some leads, especially in standard III, their depth becomes even greater (up to 9 mm) than in children of the 1st year of life.
7. The same changes in the amplitude and ratio of the R and S waves that were noted in infants continue, but they are more pronounced.
8. There is a further increase in the amplitude of the T waves, and their ratio with the R wave in leads I and II reaches 1: 3 or 1: 4, as in older children and adults.
9. Negative T waves remain (options: biphasic, smooth) in standard III and right chest leads up to V4, which is often accompanied by a downward shift of the ST segment (up to 2 mm).

ECG in preschool children: 3–6 years (Fig. 5).

1. Heart rate decreases to an average of 100 beats/min, and moderate or severe sinus arrhythmia is often recorded.
2. The high voltage of the QRS complex teeth remains.
3. EOS is normal or vertical, and very rarely there is a deviation to the right and horizontal position.
4. PQ duration does not exceed 0.15 s.
5. Q waves in various leads are recorded more often than in previous age groups. The depth of the Q waves in standard III and aVF leads remains relatively large (up to 7–9 mm) compared to that in older children and adults.
6. The ratio of the size of the R and S waves in standard leads changes towards an even greater increase in the R wave in standard leads I and II and a decrease in the depth of the S wave.
7. The height of the R waves in the right chest leads decreases, and in the left chest leads it increases. The depth of the S waves decreases from left to right from V1 to V5 (V6).
ECG in schoolchildren: 7–15 years (Fig. 6).

The ECG of schoolchildren is close to the ECG of adults, but there are still some differences:

1. Heart rate decreases on average junior schoolchildren up to 85–90 beats/min, in older schoolchildren – up to 70–80 beats/min, but there are wide fluctuations in heart rate. Moderate and severe sinus arrhythmia is often recorded.
2. The voltage of the QRS complex teeth decreases somewhat, approaching that of adults.
3. Position of the EOS: more often (50%) – normal, less often (30%) – vertical, rarely (10%) – horizontal.
4. The duration of ECG intervals approaches that of adults. The PQ duration does not exceed 0.17–0.18 s.
5. The characteristics of the P and T waves are the same as in adults. Negative T waves persist in lead V4 up to 5–11 years, in V3 – up to 10–15 years, in V2 – up to 12–16 years, although negative T waves in leads V1 and V2 are also allowed in healthy adults.
6. The Q wave is recorded inconsistently, but more often than in young children. Its value becomes smaller than in preschool children, but in lead III it can be deep (up to 5–7 mm).
7. The amplitude and ratio of the R and S waves in various leads approach those in adults.

Conclusion
To summarize, we can highlight the following features of the pediatric electrocardiogram:
1. Sinus tachycardia, from 120–160 beats/min during the newborn period to 70–90 beats/min by high school age.
2. Greater variability of heart rate, often sinus (respiratory) arrhythmia, respiratory electrical alteration of QRS complexes.
3. The norm is considered to be average, inferior atrial rhythm and migration of the pacemaker through the atria.
4. Low QRS voltage in the first 5–10 days of life (low electrical activity of the myocardium), then an increase in the amplitude of the waves, especially in the chest leads (due to the thin chest wall and the large volume occupied by the heart in the chest).
5. Deviation of the EOS to the right up to 90–170º during the newborn period, by the age of 1–3 years – transition of the EOS to a vertical position, by adolescence in about 50% of cases – normal EOS.
6. Short duration of intervals and waves of the PQRST complex with a gradual increase with age to normal limits.
7. “Syndrome of delayed excitation of the right supraventricular crest” – splitting and deformation of the ventricular complex in the form of the letter “M” without increasing its duration in leads III, V1.
8. Pointed high (up to 3 mm) P wave in children in the first months of life (due to the high functional activity of the right side of the heart in the prenatal period).
9. Often – deep (amplitude up to 7–9 mm, more than 1/4 of the R wave) Q wave in leads III, aVF in children up to adolescence.
10. Low amplitude of T waves in newborns, increasing by the 2nd–3rd year of life.
11. Negative, biphasic or smoothed T waves in leads V1-V4, persisting until the age of 10–15 years.
12. Shift of the transition zone of the chest leads to the right (in newborns - in V5, in children after the 1st year of life - in V3-V4) (Fig. 2–6).

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3. Isakov I.I., Kushakovsky M.S., Zhuravleva N.B. Clinical electrocardiography. L.: Medicine, 1984.
4. Kushakovsky M.S. Cardiac arrhythmias. St. Petersburg: Hippocrates, 1992.
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The electrical axis of the heart (EOS) is one of the main parameters of the electrocardiogram. This term is actively used both in cardiology and in functional diagnostics, reflecting the processes occurring in the most important organ human body.

The position of the electrical axis of the heart shows the specialist what exactly is happening in the heart muscle every minute. This parameter is the sum of all bioelectrical changes observed in the organ. When taking an ECG, each electrode of the system registers excitation passing at a strictly defined point. If you transfer these values ​​to a conventional three-dimensional coordinate system, you can understand how the electrical axis of the heart is located and calculate its angle relative to the organ itself.

How is an electrocardiogram taken?

ECG recording is performed in a special room, maximally shielded from various electrical interference. The patient sits comfortably on the couch with a pillow under his head. To take an ECG, electrodes are applied (4 on the limbs and 6 on chest). An electrocardiogram is recorded when calm breathing. In this case, the frequency and regularity of heart contractions, the position of the electrical axis of the heart and some other parameters are recorded. This simple method allows you to determine whether there are abnormalities in the functioning of the organ, and, if necessary, refer the patient for a consultation with a cardiologist.

What influences the location of the EOS?

Before discussing the direction of the electrical axis, you should understand what the conduction system of the heart is. It is this structure that is responsible for the passage of impulses through the myocardium. The conduction system of the heart is atypical muscle fibers that connect various areas organ. It begins with the sinus node, located between the mouths of the vena cava. Next, the impulse is transmitted to the atrioventricular node, located in the lower part of the right atrium. The next to take up the baton is the His bundle, which quickly diverges into two legs - left and right. In the ventricle, the branches of the His bundle immediately become Purkinje fibers, which penetrate the entire cardiac muscle.

An impulse entering the heart cannot escape the myocardial conduction system. This is a complex structure with fine settings, sensitively responding to the slightest changes in the body. In case of any disturbances in the conduction system, the electrical axis of the heart can change its position, which will be immediately recorded on the electrocardiogram.

EOS location options

As you know, the human heart consists of two atria and two ventricles. Two circles of blood circulation (large and small) ensure the normal functioning of all organs and systems. Normally, the mass of the myocardium of the left ventricle is slightly greater than that of the right. It turns out that all impulses passing through the left ventricle will be somewhat stronger, and the electrical axis of the heart will be oriented specifically towards it.

If you mentally transfer the position of the organ to a three-dimensional coordinate system, it will become clear that the EOS will be located at an angle from +30 to +70 degrees. Most often, these are the values ​​recorded on the ECG. The electrical axis of the heart can also be located in the range from 0 to +90 degrees, and this, too, according to cardiologists, is the norm. Why do such differences exist?

Normal location of the electrical axis of the heart

There are three main provisions of the EOS. The range from +30 to +70° is considered normal. This option occurs in the vast majority of patients who visit a cardiologist. The vertical electrical axis of the heart is found in thin, asthenic people. In this case, the angle values ​​will range from +70 to +90°. The horizontal electrical axis of the heart is found in short, tightly built patients. On their card, the doctor will mark the EOS angle from 0 to +30°. Each of these options is normal and does not require any correction.

Pathological location of the electrical axis of the heart

A condition in which the electrical axis of the heart is deviated is not a diagnosis in itself. However, such changes in the electrocardiogram may indicate various violations in the work itself important body. TO major changes The following diseases affect the functioning of the conduction system:

Cardiac ischemia;

Chronic heart failure;

Cardiomyopathies of various origins;

Congenital defects.

Knowing about these pathologies, the cardiologist will be able to notice the problem in time and refer the patient to hospital treatment. In some cases, when EOS deviation is registered, the patient requires emergency care in intensive care.

Deviation of the electrical axis of the heart to the left

Most often, such changes in the ECG are observed with enlargement of the left ventricle. This usually occurs with the progression of heart failure, when the organ simply cannot fully perform its function. It is possible that such a condition may develop in arterial hypertension accompanied by pathology large vessels and increased blood viscosity. In all these conditions, the left ventricle is forced to work hard. Its walls thicken, leading to inevitable disruption of the impulse through the myocardium.

Deviation of the electrical axis of the heart to the left also occurs with narrowing of the aortic mouth. In this case, stenosis of the lumen of the valve located at the exit from the left ventricle occurs. This condition is accompanied by a disruption of normal blood flow. Part of it is retained in the cavity of the left ventricle, causing it to stretch and, as a result, thickening of its walls. All this causes a natural change in EOS as a result of improper conduction of the impulse through the myocardium.

Deviation of the electrical axis of the heart to the right

This condition clearly indicates right ventricular hypertrophy. Similar changes develop in certain respiratory diseases (for example, bronchial asthma or chronic obstructive pulmonary disease). Some congenital heart defects can also cause the right ventricle to become enlarged. First of all, it is worth noting stenosis pulmonary artery. IN individual situations tricuspid valve insufficiency can also lead to a similar pathology.

Why is changing EOS dangerous?

Most often, deviations of the electrical axis of the heart are associated with hypertrophy of one or another ventricle. This condition is a sign of long-standing chronic process and, as a rule, does not require emergency assistance cardiologist. The real danger is the change in the electrical axis due to His bundle block. In this case, the conduction of impulses through the myocardium is disrupted, which means there is a risk sudden stop cardiac activity. This situation requires urgent intervention by a cardiologist and treatment in a specialized hospital.

With the development of this pathology, the EOS can be deviated both to the left and to the right, depending on the localization of the process. The blockade can be caused by myocardial infarction, infection of the heart muscle, as well as taking certain medications. A regular electrocardiogram allows you to quickly make a diagnosis, which means it allows the doctor to prescribe treatment taking into account all important factors. IN severe cases It may be necessary to install a pacemaker (pacemaker), which will send impulses directly to the heart muscle and thereby ensure normal functioning of the organ.

What to do if the EOS is changed?

First of all, it is worth considering that the deviation of the heart axis itself is not the basis for making a particular diagnosis. The position of the EOS can only give impetus to a more careful examination of the patient. For any changes in the electrocardiogram, you cannot do without consulting a cardiologist. An experienced doctor will be able to recognize normal and pathological conditions, and, if necessary, prescribe additional examination. This may be echocardioscopy for targeted study of the condition of the atria and ventricles, monitoring blood pressure and other techniques. In some cases, consultation with related specialists is required to decide on further management of the patient.

To summarize, several important points should be highlighted:

The normal EOS value is considered to be the range from +30 to +70°.

Horizontal (from 0 to +30°) and vertical (from +70 to +90°) positions of the heart axis are acceptable values and do not talk about the development of any pathology.

Deviations of the EOS to the left or to the right may indicate various disorders in the conduction system of the heart and require consultation with a specialist.

A change in EOS detected on a cardiogram cannot be made as a diagnosis, but is a reason to visit a cardiologist.

The heart is amazing organ, ensuring the functioning of all systems of the human body. Any changes that occur in it inevitably affect the functioning of the whole organism. Regular examinations by a therapist and an ECG will allow timely detection of serious diseases and avoid the development of any complications in this area.

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The electrical axis of the heart is a concept that reflects the total vector of the electrodynamic force of the heart, or its electrical activity, and practically coincides with the anatomical axis. Normally, this organ has a cone-shaped shape, with its narrow end directed downwards, forward and to the left, and the electrical axis has a semi-vertical position, that is, it is also directed downwards and to the left, and when projected onto the coordinate system it can be in the range from +0 to +90 0.

An ECG conclusion is considered normal if it indicates any of the following positions of the heart axis: not deviated, semi-vertical, semi-horizontal, vertical or horizontal. The axis is closer to the vertical position in thin, tall people of asthenic physique, and closer to the horizontal position in strong, stocky people of hypersthenic physique.

Electric axis position range is normal

For example, in the conclusion of an ECG, the patient may see the following phrase: “sinus rhythm, EOS is not deviated...”, or “the axis of the heart is in a vertical position,” this means that the heart is working correctly.

In the case of heart disease, the electrical axis of the heart, along with the heart rhythm, is one of the first ECG criteria that the doctor pays attention to, and in case of ECG decoding The attending physician must determine the direction of the electrical axis.

Deviations from the norm are deviation of the axis to the left and sharply to the left, to the right and sharply to the right, as well as the presence of a non-sinus heart rhythm.

How to determine the position of the electrical axis

Determination of the position of the heart axis is carried out by a doctor functional diagnostics, deciphering the ECG, using special tables and diagrams, according to the angle α (“alpha”).

The second way to determine the position of the electrical axis is to compare the QRS complexes responsible for the excitation and contraction of the ventricles. So, if the R wave has a greater amplitude in the I chest lead than in the III, then there is a levogram, or deviation of the axis to the left. If there is more in III than in I, then it is a legal grammar. Normally, the R wave is higher in lead II.

Reasons for deviations from the norm

Axial deviation to the right or left is not considered an independent disease, but it can indicate diseases that lead to disruption of the heart.

Deviation of the heart axis to the left often develops with left ventricular hypertrophy

Deviation of the heart axis to the left can occur normally in healthy individuals who are professionally involved in sports, but more often develops with left ventricular hypertrophy. This is an increase in the mass of the heart muscle with a violation of its contraction and relaxation necessary for normal operation with all my heart. Hypertrophy can be caused by the following diseases:

• cardiomyopathy (increase in myocardial mass or expansion of the heart chambers), caused by anemia, hormonal imbalances in the body, coronary disease heart, post-infarction cardiosclerosis. changes in the structure of the myocardium after myocarditis (inflammatory process in cardiac tissue);
• long-term arterial hypertension, especially with constantly high blood pressure numbers;
• acquired heart defects, in particular stenosis (narrowing) or insufficiency (incomplete closure) aortic valve, leading to disruption of intracardiac blood flow, and, consequently, increased load to the left ventricle;
• congenital heart defects often cause a deviation of the electrical axis to the left in a child;
• conduction disturbance along the left bundle branch - complete or incomplete blockade, leading to impaired contractility of the left ventricle, while the axis is deviated, and the rhythm remains sinus;
• atrial fibrillation, then the ECG is characterized not only by axis deviation, but also by the presence of non-sinus rhythm.

Deviation of the heart axis to the right is a normal variant when conducting an ECG in a newborn child, and in this case a sharp deviation of the axis may occur.

In adults, such a deviation is usually a sign of right ventricular hypertrophy, which develops in the following diseases:

• diseases bronchopulmonary system– long-term bronchial asthma, heavy obstructive bronchitis, pulmonary emphysema, leading to increased blood pressure in the pulmonary capillaries and increasing the load on the right ventricle;
• heart defects with damage to the tricuspid (three-leaf) valve and the valve of the pulmonary artery, which arises from the right ventricle.

The greater the degree of ventricular hypertrophy, the more the electrical axis is deflected, respectively, sharply to the left and sharply to the right.

Symptoms

The electrical axis of the heart itself does not cause any symptoms in the patient. Impaired health appears in the patient if myocardial hypertrophy leads to severe hemodynamic disturbances and heart failure.

The disease is characterized by pain in the heart area

Signs of diseases accompanied by deviation of the heart axis to the left or right include headaches, pain in the heart area, swelling of the lower extremities and face, shortness of breath, asthma attacks, etc.

If any unpleasant cardiac symptoms appear, you should consult a doctor for an ECG, and if an abnormal position of the electrical axis is detected on the cardiogram, further examination must be performed to determine the cause of this condition, especially if it is detected in a child.

Diagnostics

To determine the reason for deviation according to ECG axis heart left or right, a cardiologist or therapist may prescribe additional research methods:

1. Ultrasound of the heart is the most informative method, allowing to assess anatomical changes and identify ventricular hypertrophy, as well as determine the degree of impairment of their contractile function. This method is especially important for examining a newborn baby for congenital pathology hearts.
2. ECG with exercise (walking on a treadmill - treadmill test, bicycle ergometry) can detect myocardial ischemia, which may be the cause of deviations in the electrical axis.
3. Daily ECG monitoring in the event that not only an axis deviation is detected, but also the presence of a rhythm not from the sinus node, that is, rhythm disturbances occur.
4. Chest X-ray - with severe myocardial hypertrophy, an expansion of the cardiac shadow is characteristic.
5. Coronary angiography (CAG) – performed to clarify the nature of the lesions coronary arteries with ischemic disease a.

Treatment

Direct deviation of the electrical axis does not require treatment, since it is not a disease, but a criterion by which it can be assumed that the patient has one or another cardiac pathology. If, after further examination, some disease is identified, it is necessary to begin treatment as soon as possible.

In conclusion, it should be noted that if the patient sees in the ECG conclusion a phrase that the electrical axis of the heart is not in a normal position, this should alert him and prompt him to consult a doctor to find out the cause of such an ECG sign, even if there are no symptoms does not arise.

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When the EOS is in a vertical position, the S wave is most pronounced in leads I and aVL. ECG in children aged 7–15 years. Characterized by respiratory arrhythmia, heart rate 65-90 per minute. The position of the EOS is normal or vertical.

Regular sinus rhythm - this phrase means an absolutely normal heart rhythm, which is generated in sinus node(the main source of cardiac electrical potentials).

Left ventricular hypertrophy (LVH) is a thickening of the wall and/or enlargement of the left ventricle of the heart. All five position options (normal, horizontal, semi-horizontal, vertical and semi-vertical) are found in healthy people and are not pathological.

What does the vertical position of the heart axis on an ECG mean?

The definition of “rotation of the electrical axis of the heart around an axis” may well be found in descriptions of electrocardiograms and is not something dangerous.

The situation should be alarming when, with a pre-existing position of the EOS, its sharp deviation on the ECG occurs. In this case, the deviation most likely indicates the occurrence of a blockade. 6.1. P wave. Analysis of the P wave involves determining its amplitude, width (duration), shape, direction and degree of severity in various leads.

The always negative wave vector P is projected onto the positive parts of most leads (but not all!).

6.4.2. The degree of severity of the Q wave in various leads.

Methods for determining the position of the EOS.

To put it simply, an ECG is a dynamic recording electric charge, thanks to which our heart works (that is, contracts). The designations of these graphs (they are also called leads) - I, II, III, aVR, aVL, aVF, V1-V6 - can be seen on the electrocardiogram.

An ECG is a completely painless and safe test; it is performed on adults, children and even pregnant women.

Heart rate is not a disease or a diagnosis, but just an abbreviation for “heart rate,” which refers to the number of contractions of the heart muscle per minute. When the heart rate increases above 91 beats/min, they speak of tachycardia; if the heart rate is 59 beats/min or less, this is a sign of bradycardia.

Electrical axis of the heart (EOS): essence, norm of position and violations

Thin people usually have a vertical position of the EOS, while thick people and obese people have a horizontal position. Respiratory arrhythmia is associated with the act of breathing, is normal and does not require treatment.

Requires compulsory treatment. Atrial flutter - this type of arrhythmia is very similar to atrial fibrillation. Sometimes polytopic extrasystoles occur - that is, the impulses that cause them come from various parts of the heart.

Extrasystoles can be called the most common ECG finding; moreover, not all extrasystoles are a sign of the disease. In this case, treatment is necessary. Atrioventricular block, A-V (A-V) block - a violation of the conduction of impulses from the atria to the ventricles of the heart.

Block of the branches (left, right, left and right) of the His bundle (RBBB, LBBB), complete, incomplete, is a violation of the conduction of an impulse through the conduction system in the thickness of the ventricular myocardium.

The most common reasons hypertrophies are arterial hypertension, heart defects and hypertrophic cardiomyopathy. In some cases, next to the conclusion about the presence of hypertrophy, the doctor indicates “with overload” or “with signs of overload.”

Variants of the position of the electrical axis of the heart in healthy people

Cicatricial changes, scars are signs of a myocardial infarction once suffered. In such a situation, the doctor prescribes treatment aimed at preventing a recurrent heart attack and eliminating the cause of circulatory problems in the heart muscle (atherosclerosis).

Timely detection and treatment of this pathology is necessary. Normal ECG in children aged 1 – 12 months. Typically, heart rate fluctuations depend on the child’s behavior (increased frequency when crying, restlessness). At the same time, over the past 20 years there has been a clear trend towards an increase in the prevalence of this pathology.

When can the position of the EOS indicate heart disease?

The direction of the electrical axis of the heart shows the total magnitude of bioelectric changes occurring in the heart muscle with each contraction. The heart is a three-dimensional organ, and in order to calculate the direction of the EOS, cardiologists represent the chest as a coordinate system.

If you project the electrodes onto a conventional coordinate system, you can also calculate the angle of the electrical axis, which will be located where the electrical processes are strongest. The conduction system of the heart consists of sections of the heart muscle consisting of so-called atypical muscle fibers.

Normal ECG readings

Myocardial contraction begins with the appearance of an electrical impulse in the sinus node (which is why the correct rhythm healthy heart called sinus). The myocardial conduction system is a powerful source of electrical impulses, which means that electrical changes that precede cardiac contraction occur in it first of all in the heart.

Rotations of the heart around the longitudinal axis help determine the position of the organ in space and, in some cases, are an additional parameter in diagnosing diseases. The position of the EOS itself is not a diagnosis.

These defects can be either congenital or acquired. The most common acquired heart defects are a consequence of rheumatic fever.

In this case, a consultation with a highly qualified sports doctor is necessary to decide on the possibility of continuing to play sports.

A shift in the electrical axis of the heart to the right may indicate right ventricular hypertrophy (RVH). Blood from the right ventricle enters the lungs, where it is enriched with oxygen.

As in the case of the left ventricle, RVH is caused by coronary heart disease, chronic heart failure and cardiomyopathies.

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Cardiologist

Higher education:

Cardiologist

Saratov State Medical University named after. IN AND. Razumovsky (SSMU, media)

Level of education - Specialist

Additional education:

"Emergency Cardiology"

1990 - Ryazan medical school named after academician I.P. Pavlova

EOS (electrical axis of the heart) is an indicator of the electrical parameters of the heart muscle. Important information necessary to make a cardiac diagnosis is the direction of EOS.

What is the vertical position of the EOS

There are several options for the position of the electrical axis of the heart. It can have a horizontal (semi-horizontal) and vertical (semi-vertical) direction. All of the listed varieties do not relate to pathologies - they are often detected when in good condition health. The vertical position of the EOS is typical for tall patients with a thin build, children, and adolescents. Horizontal - found in short people with a wide chest.

In some cases, significant displacements of the EOS occur. The reasons for this are that the patient has:

• coronary heart disease;
• cardiomyopathy;
• chronic heart failure;
• congenital anomalies of the heart muscle.

The position of the heart axis is considered by cardiologists as an additional indicator in diagnosing heart diseases, and not as independent disease. If its deviation is outside the norm (more than +90 degrees), you will need consultation with a specialist and a thorough examination.

When is the diagnosis of “sinus tachycardia vertical position of the EOS” made?

The diagnosis of “sinus tachycardia with a vertical position of the EOS” is often found in children and adolescents. It implies an acceleration of the rhythm in which the sinus node operates. An electrical impulse emanates from this area, initiating contraction of the heart and determining the speed of its work.

Sinus tachycardia at this age is considered normal. Heart rate readings may exceed 90 beats per minute. In the absence of serious complaints, normal results analysis, this condition is not regarded as a manifestation of pathology.

Tachycardia requires more serious consideration when it appears:

• various forms of shortness of breath;
• feeling of constriction in the chest area;
• chest pain;
• dizziness, fainting, low blood pressure (in cases where orthostatic tachycardia develops);
• panic attacks;
• increased fatigue and loss of performance.

Postural orthostatic tachycardia syndrome leads to an increase in heart rate when changing body position ( standing up abruptly). This is often observed in people whose professional activities are associated with increased physical activity(for general workers, loaders, storekeepers).

Possible long-term consequences of sinus tachycardia are heart failure and other diseases.

Diagnosis of sinus tachycardia

Diagnosis of sinus tachycardia requires the use of various analytical techniques. It becomes mandatory to study the patient’s medical history and clarify information regarding the types of medications used by him in the past. Such moments make it possible to identify the presence of factors and circumstances that caused the onset of the disease.

Mandatory are:

1. Physical examination of the patient, including examination of the condition skin, assessment of the degree of its oxygen saturation.
2. Listening to breathing and heart rate (in some cases, with little physical activity).
3. General and biochemical blood test to determine the level of leukocytes, cholesterol, potassium, glucose, urea.
4. Urinalysis necessary to exclude diseases genitourinary system among the suspected causes of the development of pathology.

The state of the thyroid gland makes it possible to determine the degree of its influence on the heart rate. As additional methods diagnostics, vagal tests and daily monitoring are carried out.

The most important method for diagnosing sinus tachycardia remains the cardiogram, which is based on recording electrical oscillations that occur during the work of the heart.

Treatment methods

In uncomplicated cases of sinus tachycardia, changes in the patient's diet and lifestyle are sufficient. You will need to minimize the presence of spicy and excessively salty dishes on the menu, give up strong tea and coffee, alcohol, and chocolate. Walking on fresh air without intense physical activity.

If there is a need for therapeutic treatment, medications are selected based on the reasons for the development of the pathology. The treatment plan is drawn up various specialists- cardiologist, endocrinologist, phlebologist, vascular surgeon.

Traditionally, therapy is carried out with the appointment:

• beta-blockers (Bisoprolol, Metoprolol);
• non-dihydropyridine calcium antagonists (Verapamid, Diltiazem);
• drugs that suppress the synthesis of thyrotropin (Metizol, Carbimazole);
• sedatives (tinctures of motherwort, Persen, valerian extract).

In the case of diagnosing highly symptomatic sinus tachycardia, it becomes advisable to use surgical methods treatment - radiofrequency catheter ablation of the sinus node with installation of a permanent pacemaker.

Help from traditional medicine

Combination of nuts and dried fruits

The process of preparing a “medicine” from nuts (Brazil) and dried fruits will require combining 2 tbsp. l. main components, dried apricots, figs, raisins, hazelnuts. The ingredients are thoroughly crushed with a blender, pour 300 ml natural honey. The composition is taken 1 tsp. three times a day for a 3-week course. If you are obese and have problems with thyroid gland It is better to refuse the product.

Lemon-garlic mixture

The lemon-garlic mixture contains 10 peeled heads of garlic, 10 diced and peeled citrus fruits. The components are mixed in a blender, liquid honey is added. After thorough mixing, store in a dark place for at least 1 week. Then take 4 times a day, 1 dessert spoon. The course lasts 1 month.

Hawthorn infusion

A tablespoon of dried hawthorn flowers is poured with an incomplete glass of boiling water and left for at least half an hour. The infusion is drunk three times a day, 100 ml, regardless of meals. The recommended duration of treatment is 1–3 months.

Sinus tachycardia often requires integrated approach to treatment. For getting positive results therapy, the patient will need to comply with all medical prescriptions and recommendations, refuse bad habits, control your motor activity. When saving sedentary lifestyle life, smoking, eating high-calorie foods, alcohol, the effectiveness of even the most professional treatment, as well as the best traditional methods, will decrease significantly.

Article publication date: 05/14/2017

Article updated date: 12/21/2018

From this article you will learn what EOS is and what it should be normally. When the EOS is deviated slightly to the left - what does this mean, what diseases can it indicate. What treatment may be required.

The electrical axis of the heart is diagnostic criterion, which displays the electrical activity of the organ.

The electrical activity of the heart is recorded using an ECG. Sensors are placed on different areas of the chest, and to find out the direction of the electrical axis, it (the chest) can be represented as a three-dimensional coordinate system.

The direction of the electrical axis is calculated by the cardiologist during the course. To do this, he sums the values ​​of the Q, R and S waves in lead 1, then finds the sum of the values ​​of the Q, R and S waves in lead 3. Next, it takes the two obtained numbers and calculates the alpha angle using a special table. It's called the Diede table. This angle is the criterion by which it is determined whether the location of the electrical axis of the heart is normal.

The presence of a significant deviation of the EOS to the left or right is a sign of cardiac dysfunction. Diseases that provoke EOS deviation almost always require treatment. After getting rid of the underlying disease, the EOS takes a more natural position, but sometimes it is impossible to completely cure the disease.

To resolve this problem, consult a cardiologist.

The location of the electrical axis is normal

In healthy people, the electrical axis of the heart coincides with the anatomical axis of this organ. The heart is located semi-vertically - its lower end is directed down and to the left. And the electrical axis, like the anatomical one, is in a semi-vertical position and tends down and to the left.

The standard alpha angle is from 0 to +90 degrees.

The location of the anatomical and electrical axes depends to some extent on body type. Asthenics ( skinny people With tall and long limbs), the heart (and, accordingly, its axes) is located more vertically, and in hypersthenics (short people with a stocky build) - more horizontally.

Normal alpha angle depending on body type:

Significant displacement of the electrical axis to the left or right side- This is a sign of pathologies of the conduction system of the heart or other diseases.

A deviation to the left is indicated by a minus alpha angle: from -90 to 0 degrees. About its deviation to the right - values ​​from +90 to +180 degrees.

However, it is not at all necessary to know these numbers, since in case of violations in the ECG interpretation you can find the phrase “EOS is deviated to the left (or right).”

Reasons for shift to the left

Deviation of the electrical axis of the heart to the left – typical symptom problems with the left side of this organ. It could be:

• hypertrophy (enlargement, proliferation) of the left ventricle (LVH);
• – Impaired impulse conduction in the anterior part of the left ventricle.

Causes of these pathologies:

Symptoms

EOS displacement itself does not have characteristic symptoms.

The diseases that accompany it can also be asymptomatic. This is why it is important to undergo an ECG for preventive purposes– if the disease is not accompanied unpleasant signs, you can find out about it and start treatment only after deciphering the cardiogram.

However, sometimes these diseases still make themselves felt.

Symptoms of diseases that are accompanied by a displacement of the electrical axis:

But let us repeat once again - symptoms do not always appear; they usually develop late stages diseases.

Additional diagnostics

To find out the reasons for the EOS deviation, the ECG is analyzed in detail. They may also assign:

After a detailed examination, appropriate therapy is prescribed.

Treatment

The deviation of the electrical axis of the heart to the left in itself does not require specific treatment because it is just a symptom of another disease.

All measures are aimed at eliminating the underlying disease, which is manifested by displacement of the EOS.

Treatment for LVH depends on what caused the myocardial growth

Treatment of blockade of the anterior branch of the left bundle branch - . If it occurs as a result of a heart attack - surgical repair blood circulation in the coronary vessels.

The electrical axis of the heart returns to normal only if the size of the left ventricle is returned to normal or the conduction of impulses through the left ventricle is restored.

In cardiological practice, there is a special term that reflects cardiac electrical processes. It is called the electrical axis of the heart (EOS). Its direction characterizes the bioelectric changes occurring inside the heart during its contraction, or rather their total value.

Atypical muscles make up the conduction system. They ensure the synchronization of heartbeats. An electrical impulse is generated in the sinus node. This gives rise to myocardial contraction. It is for this reason that the normal rhythm of the human heart is called sinus.

As already stated, various diseases have different effects on the angle of inclination of the EO.

What does it mean if the electrical axis of the heart is deviated to the left? This may be a symptom of left ventricular hypertrophy. That is, it increases and its overload occurs. This can occur with prolonged high blood pressure. Vessels have great resistance to blood flow. Therefore, the left ventricle exerts great effort. It grows, which means it develops. This is precisely the main reason for moving the axis to the left.

Hypertrophy can develop when the valvular section of the left ventricle is damaged. This is caused by ostial aortic stenosis. In this condition, there are great difficulties in sending blood out of the left ventricle, or it becomes overloaded with returning blood. Such disorders may be acquired or may be congenital. In most cases, the ventricle enlarges after attacks of rheumatism. The disease also occurs in athletes. In the latter case sports career may end suddenly.

If the electrical axis of the heart is shifted to the left, this may indicate all sorts of heart blockades and conduction disturbances inside the ventricle.

The electrical axis of the heart is shifted to the right with enlargement of the right ventricle. Coming out of it, the blood is transported to the lungs for oxygen enrichment. Hypertrophy can be provoked by various diseases of the pulmonary system, such as asthma, increased pulmonary pressure or obstruction. Hypertrophy also occurs with pulmonary stenosis or incorrect functioning of the tricuspid valve. In addition, the disease can be a consequence of ischemia, cardiomyopathy, etc.

These diagnoses cannot be made only by the location of the EOS. This is only an additional indicator determined when identifying various kinds ailments. If the electrical axis of the heart is deviated beyond the range of zero to plus ninety degrees, you need to consult a doctor and conduct some research.

As is known, the main factor regulating axis displacement is hypertrophy. This disease can be determined by ultrasound examination. In general, all diseases that cause a displacement of the electrical axis of the heart are characterized by a variety of clinical manifestations and several additional studies are necessary to identify them. A sudden change in the position of the axis, detected for the first time on an electrocardiogram, can be provoked by some kind of cardiac blockade.

Treatment for displacement of the electrical axis of the heart is not required. This parameter is one of the electrocardiological signs, based on which it is necessary to find out the reasons for its manifestation. And this will only be done by an experienced cardiologist based on the results of the prescribed examination.