How to visually determine the blockade of the left and right legs of the bundle of the His on the ECG tape

The blockade of components within the bundle bundle structure belongs to the class of intraventricular arrhythmias.

It means a violation of the normal passage of an electric pulse through the fibers responsible for ventricular contractions, and can be either complete or incomplete( affecting individual branches in the thickness of the heart muscle).

This type of heart rhythm disorder can be permanent or intermittent.

Contents of

  • 1 What to look for in a cardiogram
  • 2 Normal indications
  • 3 Right-hand pathology
  • 4 Left-side
  • 5 Diagnosis
  • 6 Additional studies
  • 7 Treatment

What to look for in a cardiogram

A complete characteristic of this pathology can be presented on an electrocardiogram( ECG).On the resulting conducting EKG tape results recorded in several graphs corresponding to the three standard limb leads( I, II, III), three power limb leads( aVL, aVR, aVF) and the six chest leads( from V1 to V6).

It is by the form of the line fixed in each of these leads that the doctor can establish signs of blockade of the components of the bundle of His.

Normal indicators

electrocardiogram, indicating the absence of pathological changes in the heart function, necessarily involves the presence prongs P, T, ventricular complexes QRS and all ranges and segments as smoothly into each other and formed unbroken line deviations from the isoelectricline.

And the listed elements should meet some parameters, which the doctor independently calculates in seconds and millimeters with a special ruler, and also evaluates visually. By normal ECG parameters relates:

  1. correct rhythm ( in any of the leads any RR interval is equal or differs by no more than 10% from the average of all neighboring RR intervals).
  2. The heart rate of the is in the range of 60-90 beats per minute.
  3. The sinoatrial node works as the main driver of the heart rhythm( in leads II and III there are positive - above the isoline - the P teeth located in front of all QRS complexes).No
  4. deceleration or acceleration conductivity muscle fibers( P-wave width is less than 0.10 second, PQ interval, - from 0.120 to 0.20 seconds, the complex QRS - from 0.080 to 0.120 seconds).
  5. The electrical axis of the heart is in the range from +30 to +60 degrees.
  6. Normal atrial wave parameters P ( duration up to 0.10 seconds, the height up to 2.5 mm; necessarily positive in lead I, II, aVF, V2-V6; always negative - lower contour - in lead aVR; dome shape withoutserration and bifurcation into two denticles).
  7. The normal parameters of the QRS complex( total duration 0.080-0.120 seconds, the duration of the Q wave is less than or equal to 0.030 seconds, and the amplitude is a quarter of the height of the R wave).
  8. Normal parameters of the RS-T segment ( the segment should be located on the neutral contour, without serration).Normal tooth
  9. parameters T ( must always be positive in lead I, II, aVF, V2-V6, is not serrated, without splitting; always negative in lead aVR).
  10. The QT interval is located on the contour line, straight.
Cardiac diseases are very clearly visible on the electrocardiogram data. The parameters of cardiac pathologies differ significantly from normal ones, especially the various blockades, including the blockade of the components of the bundle of His.

Right-hand pathology

This variant of the defeat of the impulse conduction along the bundle of the Gis is much more common. The signs of an electrocardiogram characterizing the complete blockade of the right bundle of the bundle are:

  • The QRS complex duration is longer than 0.120 seconds.
  • Presence of deformed continuous S-wave in leads V4-V6.
  • Presence of a broken into three phases( similar to the letter "M") of QRS in leads V1-V3.

Speaking about the signs of incomplete blockade of the right leg of the bundle of the Hyis, it is worth noting the absence on the ECG of the pathologically long QRS complex( its length is either normal or at the upper limit of the norm in the range of 0.090 to 0.110 seconds), but the presence of three-ventricular complexes.

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The left leg in its structure has front and rear branchlets , feeding blood from various arterial vessels. As a rule, impairment of the passage of a pulse in this department is not accompanied by a sharp expansion of QRS complexes, as in the case of damage to the right leg, but it gives a vivid picture of the deviation of the electric cardiac axis in the frontal plane.

To visual signs of the complete( affecting both branches) left leg blockades on the ECG include:

  • Ventricular lengthening may be longer than 0.120 seconds.
  • Presence of deep long S teeth in lead V4-V6.
  • Presence of long and deformed teeth R in lead I, aVL and V5-V6.
  • Absence of Q on graphs I, V5-V6.

The blockade of the anterior branch of the left pedicle of the Unseen is as follows:

  • A marked deviation of the axis of the heart in the left side( from -30 to -90 degrees).
  • Ventricular complex of normal duration.
  • Small teeth R in combination with deep teeth S in II, III and aVF.
  • Small-sized teeth Q in I and aVL.

The blockade of the posterior branch of the left leg of the Hisnus looks like:

  • A marked deviation of the axis of the heart in the right side( from +120 to +180 degrees).
  • Ventricular complex of normal duration.
  • Small-sized teeth Q in combination with high-amplitude teeth R in II, III and aVF.
  • Small-sized teeth R in I and aVL.

More on determining the blockage of the right or left arms of the bundle on the results of the ECG, see the video:

Diagnosis of

In modern cardiology, blockade of the legs of the Hyis does not constitute an independent nosological unit, but characterizes the electrocardiographic symptom of the disease passed in the ICD( International Classification of Diseases).

If an ECG is found on the above features that are suitable for describing the blockade of the legs, , the doctor necessarily identifies the root cause of this rhythm disturbance and diagnoses in accordance with state recommendations, and considers the blockade to be a manifestation of the disease.

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Additional Studies

As is known, not only the ECG method, despite many advantages, helps in identifying and clarifying the diagnosis in a cardiac patient. The doctor can include the following types of research in the patient survey plan:

  • Setting the holter for daily cardiac rhythm monitoring to determine the frequency of arrhythmia, the degree of its severity.
  • EchoCG ( echocardiography), which is a technique for detecting organic changes in the heart tissues, the size of its chambers, the function of contractility, the force of the discharge of blood.
  • CPEEG ( transoesophageal electrocardiography) in case of ineffectiveness of the usual ECG study.
  • MSCT - method of multispiral computed tomography.
  • MRI of the heart.
In addition, a cardiologist can appoint consultations from related specialists of a narrower profile, such as arrhythmology and cardiosurgeons.

Treatment of

Therapy of this type of heart rhythm disorder begins with a change in the lifestyle of the patient. You should expose yourself to less stressful effects, engage in limited physical activity, have more rest in the fresh air, give up all the usual intoxications, adhere to the principles of proper nutrition.

Medical treatment of blockade of the legs of the bundle of the Hyis completely depends on the organic heart disease, which was the reason for the development of rhythm disturbance. The following drugs can be used:

  1. Antihypertensive for systematic therapy and control of high blood pressure( ACE inhibitors - lisinopril, ramipril, enalapril; cardioselective adrenergic receptor blockers - bisoprolol, atenolol, propranolol; angiotensinogen receptor antagonists - valsartan, losartan; channel antagonistscalcium - verapamil, amlodipine).
  2. Antiaggregants to prevent the development of thrombi( Plavix, clopidex, plagril, thrombotic ACC).
  3. Antianginal therapy directed to ischemic heart disease( nitroglycerin, monochinkve, isoket).
  4. Statins ( simvastatin, atorvastatin, rosuvastatin) with lipid-lowering and preventing the development of atherosclerotic plaques effect.
  5. Diuretics ( Lasix, Diver).

For lung diseases that caused the "pulmonary heart" and blockade of the legs, we apply atrovent, ferodual, беклазон, спирива, беротек, форадил.

As with any medication, the need for prior consultation with the doctor is mandatory for each patient.

In addition to medical treatment, the surgical device of the pacemaker is also used, but it is performed in the absence of a positive effect of pharmacological agents.

Block block of the bundle, being a serious ECG-sign of cardiac pathology, requires close monitoring of the patient from the treating doctor and no less attentive attitude on the part of the patient himself.

Heart rhythm disturbances are often the cause of death, which is the reason why immediately needs to seek medical care from if they have a feeling of heartbeat or cardiac fading.