Atrial hypertrophy

Introduction to atrial hypertrophy Long-term atrial overload, increased pressure, can lead to atrial hypertrophy, the response on the ECG for the p-wave amplitude increased, P wave time limit is normal or no significant extension. basic knowledge The proportion of illness: 0.002% Susceptible people: no specific population Mode of infection: non-infectious Complications: pulmonary embolism

Atrial hypertrophy

ECG changes in atrial hypertrophy must be combined with clinical considerations. If the patient has congenital heart disease (such as atrial septal defect, tetralogy of Fallot, pulmonary stenosis) or chronic obstructive emphysema, pulmonary heart disease.

Atrial hypertrophy prevention

Prevention should begin to treat primary heart disease from the prevention and treatment of causes and causes, and control the factors that induce atrial hypertrophy.

Atrial hypertrophy Complications pulmonary embolism

Pulmonary embolism, sudden cardiac death, etc. may occur.

Atrial hypertrophy symptoms common symptoms palpitations, flustered, high blood pressure, chest tightness, dizziness

The enlargement of the atrium is less indicative of atrial hypertrophy. Atrial enlargement causes the atrial muscle fiber to grow thicker and the room conduction beam to pull and damage, resulting in changes in the amplitude and direction of the entire atrial muscle depolarization vector. The main manifestations of the electrocardiogram are the amplitude of the P wave, the depolarization time and the morphological change.

The heart is a pumping organ that ages with the age of the person, and of course there are organic lesions. The visceral function of the elderly is declining, the vascular elasticity is weakened, the blood pressure is increased, and the cardiac load is increased. If accompanied by myocardial infarction, the coronary blood supply is less severe, and the heart pumping function is reduced. At this time, the myocardial fiber will be compensatory. The thickening of the atrium will increase in a long time, and the atrial enlargement is a manifestation of weakened heart function, depending on the clinical level.

Atrial hypertrophy check

Heart vector diagram change

When atrial hypertrophy occurs, the main change in the P-vector loop is a significant increase in the ring to the right front and bottom. The frontal P-ring is more downward than normal, showing a willow-like shape. The maximum vector in the counterclockwise direction is at +75° to the right, but rarely exceeds +90°, almost parallel to the aVF lead axis, resulting in aVF lead P wave. Abnormally high, sometimes up to 0.5mV or more. Similarly, the maximum vector of the P-ring is nearly parallel to the directions of II, III, and the lead axis, so the P-waves of the II and III leads are also abnormally high. The P maximum vector loop is almost perpendicular to the I and aVL lead axes. Therefore, the I and aVL lead P waves are small, sometimes bidirectional or inverted. On the lateral plane, the main change of the P-ring is to increase to the front, and the maximum vector of the P-ring is nearly parallel to the direction of the V1, V2 lead axis, and the direction of the V5, V6 lead axis is nearly perpendicular. Therefore, the P wave of the V1 and V2 leads is erected high, while the P wave of the V5 and V6 leads is relatively flat. Such P wave changes are more common in patients with chronic pulmonary heart disease and pulmonary hypertension, and are therefore referred to as "pulmonary P waves."

ECG performance

1, P wave voltage increase II, III, aVF lead appears high and sharp P wave, the amplitude is greater than 0.25mV (foreign scholars use 0.20mV as the diagnostic criteria), known as "lung P wave". In chronic emphysema combined with right atrial hypertrophy, the QRS voltage is reduced and the P-wave voltage is correspondingly reduced. Therefore, the P wave voltage of the lead II, III, and aVF leads to a diagnostic standard of less than 0.20 to 0.25 mV. At this time, as long as the P wave is sharp, the voltage reaches 1/2 of the same lead R wave. That is, the existence of right atrial hypertrophy should be considered. I, aVL lead P wave is low or inverted.

In the V1 ~ V2 lead, P wave amplitude 0.15mV (some authors believe that 0.20mV is the diagnostic criteria), some authors analyzed, found that PV2 amplitude > 0.15mV, its diagnostic sensitivity exceeds PII> 0.25mV. The V1 lead sometimes has a two-way P wave that is positive and negative, and its initial forward wave is high and sharp. The P wave of the V4 to V6 lead may be bimodal, and the first peak is larger than the second peak.

Some congenital heart diseases such as tetralogy of Fallot, atrial septal defect, etc. can occur in right atrial hypertrophy, called "congenital P wave." The electrocardiogram is characterized by a spike-like P wave appearing in the I lead, and the P wave in the I lead is higher than the lead II and III. The P-wave changes in the chest lead are the same as the typical "lung-type P-wave", and spike-like P waves appear in the V1 and V2 leads.

2. Atrial repolarization abnormalities change the right atrial hypertrophy. As the atrial depolarization vector increases, the atrial repolarization vector (Ta wave) also increases, and its direction is opposite to that of the P wave, which is characterized by a slight downward shift of the PR segment.

3, P wave time on each lead, P wave time generally does not exceed 0.10s. Because the right atrium starts very early, even if the depolarization time is extended, it will not be extended to the left atrium.

Diagnosis and diagnosis of atrial hypertrophy

Diagnostic criteria

1. PII, III, AVF 0.25 mV, PV1, V2 0.15 mV.

2, P electric axis right deviation, +75 ° ~ +90 °.

3. The P wave time is not extended.

4, V1 lead R / S > 1 (no right bundle branch block). If the index of V1 lead R/S>1 is increased, the specificity of the above diagnostic indicators can be significantly increased.

Differential diagnosis

1, atrial infarction

P-wave enlargement and deformation may occur in atrial infarction, but atrial infarction is complicated by ventricular infarction. Therefore, myocardial infarction pattern appears on ECG. In addition, atrial infarction may have elevated PR or horizontal down. This graph is rare. The house is fat.

2, hypokalemia

Hypokalemia may cause P wave to increase and sharpen, but at the same time, U wave increases, TU fusion, T wave low level, inverted, ST segment down and so on.

3, a transient "lung P wave"

Acute right ventricular infarction, pulmonary embolism due to increased right atrial pressure, transient "pulmonary P wave" may occur. In addition, tachycardia, sympathetic excitation, deep inhalation, and breath holding action can increase the pressure in the thoracic cavity, which can also cause the P wave voltage to rise temporarily. Combined with clinical manifestations, the above situation is not difficult to identify.

4, intermittent right atrial block

Sometimes "pulmonary P wave" can appear intermittently in the same electrocardiogram, more common when the heart rate increases. This obviously cannot be explained by an increase in right atrial hypertrophy or right atrial load. The most likely mechanism is due to intermittent right atrial block and belongs to the category of 3-phase in-hospital block.

5, pseudo "pulmonary P wave"

Sometimes left atrial hypertrophy in the II, III, aVF lead P wave is high and sharp, like "pulmonary P wave". Careful observation reveals that the P wave start vector (first peak) does not increase, but the terminal vector (second peak) increases. In addition, the V1 lead terminal negative wave is very obvious, and the absolute value of PtfV1 is >0.04. Mm·s. Most of these patients have hypertension, and left ventricular hypertrophy can also occur on the ECG.

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