Left atrial rhythm

Introduction to left atrial rhythm Left atrial rhythm (left) is a regular, normal heart rate in 1963, and the ectopic rhythm is located in the left atrium. It is a rare arrhythmia in clinical practice. Left atrial rhythm mostly occurs on the basis of organic heart disease, such as congenital heart disease (atrial septal defect, ventricular septal defect, patent ductus arteriosus, etc.), rheumatic heart disease, hypertensive heart disease, coronary heart disease, myocardial Infarction, pulmonary heart disease and hepatitis, schizophrenia, some healthy people. basic knowledge The proportion of illness: 0.1%-0.3% Susceptible people: no specific population Mode of infection: non-infectious Complications: hypotension

Left atrial rhythm

Causes:

Left atrial rhythm mostly occurs on the basis of organic heart disease, such as congenital heart disease (atrial septal defect, ventricular septal defect, patent ductus arteriosus, etc.), rheumatic heart disease, hypertensive heart disease, coronary heart disease, myocardial Infarction, pulmonary heart disease and hepatitis, schizophrenia, some healthy people.

Pathogenesis:

The ectopic pacemaker of the left atrial rhythm can be located in the anterior wall, posterior wall, upper part or lower part of the left atrium. Due to different parts, the depolarization vector of the atrium is different, but the total excitation direction is from left to right, so PV6 Always inverted.

Left atrial rhythm prevention

Because the left atrial rhythm has no significant effect on hemodynamics, no special prevention and treatment is needed. If necessary, the frequency of sinus rhythm can be increased, and the left atrial rhythm can disappear by itself. Eat more fresh vegetables and fruits often eat some fresh vegetables, melons, bean sprouts, kelp, seaweed, fungus and other foods, have the effect of preventing hardening of the blood vessels. Regular consumption of celery, grass, tomatoes and other foods can lower blood pressure. Heart disease patients should eat more fruits such as slag, sakura, and fruit.

Left atrial rhythm complications Complications

Rheumatic heart disease, coronary heart disease, myocardial infarction, pulmonary heart disease, and hepatitis.

Left atrial rhythm symptoms Common symptoms Chest tightness, sweating, abnormal palpitations, fainting, low blood pressure, dizziness

Symptoms of left atrial rhythm:

Palpitations, dizziness, hypotension, abnormal sweating, chest tightness, syncope. The clinical symptoms are mostly the manifestations of the primary disease, and the left atrial rhythm itself has no obvious clinical symptoms.

The palpitations, also known as palpitation, are due to people's subjective feelings of a discomfort to the heart beat. The palpitations can be caused by changes in the frequency, rhythm, or contraction intensity of the heart activity, or when the heart activity is completely normal, and the latter is caused by people's sensitivity to their own heart activity. Healthy people generally only feel palpitations when they are strenuous, mentally stressed or highly excited. This is normal, and in some pathological situations, such as too fast heart rate, too slow, and premature beats, the patient's main Symptoms are a few cases of heart and mind, such as cardiac neurosis or excessive anxiety, although there is no arrhythmia or organic heart disease, but because of increased sympathetic tone, strong heartbeat, patients often see a heart.

Left atrial rhythm examination

Electrocardiogram examination

(1) typical ECG performance of left atrial rhythm:

The 1P wave is at V6 and the I lead is inverted.

2 The P-waves of other leads vary depending on the position of the ectopic pacemaker, for example:

A. Posterior wall of the left atrium: PV1 is upright and has a dome-shaped shape.

B. Left atrial anterior wall: PV1 ~ V6 are all inverted (sometimes PV1, PV2 erect).

C. The lower part of the anterior or posterior wall of the left atrium: PII, PIII, PaVF is inverted, if the anterior wall is PV1, inverted, and the posterior wall is PV1 erect.

D. The upper wall of the left atrium or the upper part of the posterior wall: PII, PIII, PaVF is upright, if the front wall is PV1 inverted, the rear wall is PV1 upright.

The 3V1 lead P wave can be dome-shaped when it is upright.

The 4P-R interval is 0.12 to 0.20 s.

5QRS wave shape, normal time limit, supraventricular, rhythm.

6 frequency and sinus rhythm, can be as slow as 45 ~ 59 times / min, as fast as 100 ~ 120 times / min.

(2) A detailed description of the typical electrocardiogram of the left atrial rhythm:

1 P-wave morphology of limb leads:

A.PI lead: PI wave is inverted because the impulse of the left atrium is transmitted from left to right, and its depolarization direction deviates from the electrical axis of the I lead. If the impulse originates from the posterior part of the left atrium, the impulse will be from the right. Left conduction, according to the principle of Burger's inequilateral triangle, the I lead is at an angle to the horizontal line, and the I lead is tilted to the positive side. Therefore, when the left atrium vector is up and to the right, it can still be projected on the positive side of the I lead. The P-wave of the I lead is flat or bidirectional, and therefore, the P-wave erect of the I lead cannot deny the left atrial rhythm.

B. II, III and aVF leads: II, the P wave on the aVF lead is generally inverted, the P wave in the PIII lead is mostly inverted, a few are bidirectional or flat; the P wave of the aVR is always upright, the P of the aVL The waves are mostly erect, but they can also be flat, two-way or even inverted. The P-inversion of II, III, aVF is due to the pacing point located at the lower part of the anterior or posterior wall of the left atrium, and the atrial axis is between -75° and -120°. The atrial vector is from bottom to top, so the projection is caused by the negative side of the lead axis of II, III, aVF. For example, the pacing point is in the upper part of the left atrium, and the atrial axis is between +180° and +90°. The atrial vector is right, downward and backward, so it is projected on the positive side of the II, III, aVF lead axis, so that the P wave direction on the II, III, aVF leads is roughly normal.

2 P wave shape of the right chest lead (V1 ~ V3): P wave of V1 is always upright, P wave of V2, V3 is not uncommon, but also has two-way or flat, in rare cases V3 The wave can be inverted.

3 P-wave morphology of the left chest lead (V4 ~ V6): P wave of V4 ~ V6 is often inverted, Mirowski believes that the P wave inversion of V6 lead is the most sensitive and most characteristic change in the diagnosis of left atrial rhythm, as long as The P wave of the V6 lead is inverted, and even if the P wave of V1 is upright or flat, it can be diagnosed as left atrial rhythm.

4P-R interval: There is no significant difference between left atrial rhythm and normal sinus rhythm, and atrioventricular block can also occur; PR interval can also be shortened to 0.10s.

5 The frequency of left atrial rhythm, influencing factors: left atrial rhythm is the same as sinus rhythm, rhythm is regular, frequency range is similar, can be as slow as 45 ~ 59 times / min, as fast as 101 ~ 120 times / min, some people think Exercise, oppression of the eyeball or Valsalva exercise, or sneezing, etc., can transform the left atrial rhythm and sinus rhythm, there is a report that the left atrial rhythm is related to the body position, occurs in the supine position, sitting or erect can be converted into a sinus Sexual rhythm.

It has been reported that left atrial rhythm can be complicated by atrial flutter. The flutter wave can be dome-shaped on the V1 lead. The atrial flutter wave is inverted on the V5 and V6 leads, indicating that the ectopic pacemaker is at the left during atrial flutter. room.

(3) Classification of atrial rhythm electrocardiogram:

Mirowski pointed out that the left atrial rhythm seen in the clinic has the following three types:

Type I: I, V6 lead P wave inversion, V1 visible dome sharp P wave.

Type II: I, V6 lead P wave inversion, there is no dome sharp P wave in V1.

Type III: P wave inversion of V6 lead, P wave of I lead is upright or flat.

2. Electrophysiological examination

Through the intra-atrial electrophysiological mapping of patients with left atrial rhythm, the impulse sequence and the earliest excitatory point in the atrium were understood. The results showed that: I lead P wave inversion and V6 lead P wave inversion or low level is the diagnosis of left atrium. The necessary criteria for heart rhythm, while the V1 lead dome-shaped P-wave is only an auxiliary diagnostic criterion.

Diagnosis of left atrial rhythm

diagnosis

Diagnosis can be confirmed based on medical history, symptoms, signs, and electrocardiographic findings and electrophysiological findings.

Differential diagnosis

1. Atrioventricular junctional heart rhythm and coronary sinus rhythm: Cohn et al. believe that the atrioventricular junction rhythm and coronary sinus rhythm can not be distinguished, and there is no clinically significant difference, so they are collectively referred to as atrioventricular junction rhythm. When the atrial impulse is in the retrograde direction, the P-wave axis of the limb lead representing the frontal plane vector cannot identify the junctional heart rhythm. Only the chest lead representing the horizontal plane vector can identify the atrioventricular junction rhythm because of its P. The wave space vector is from right to left, from front to back, so PV1 should be inverted, flat or bidirectional, and there is no dome-shaped shape. PV4V6 is upright, and the left atrial rhythm P wave space vector is opposite, from left to right. From the back to the front, therefore PV4 ~ V6 should be inverted, PV1 upright can present a special shape.

2. Right atrial overload: When the right atrial load is too heavy, it can cause PI inversion, which is easy to be mistaken for left atrial rhythm, but the I lead is not in the horizontal direction, but the negative side is inclined downward, so the right atrial load increases. When large, the atrial axis is right but not necessarily more than 90°, it can be projected on the negative side of the I lead axis, so that the PI is inverted, but the P wave direction of the II, III, aVF lead is normal, and PV5~V6 should be upright.

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