early repolarization syndrome
Introduction
Introduction to early repolarization syndrome Early repolarization syndrome (ERS) is a common normal ECG variation, mainly characterized by chest pain, chest tightness, palpitations, ST-segment elevation on ECG, similar to angina pectoris, hyperacute period of myocardial infarction, Patterns such as acute pericarditis are easily misdiagnosed as organic heart disease. basic knowledge Sickness ratio: 0.0001% Susceptible people: no specific population Mode of infection: non-infectious complication:
Cause
Causes of early repolarization syndrome
Cause
In recent years, with the wide application of electrocardiogram, the detection rate of ERS has been increasing, and it is thought that it may be related to the increase of vagal tone, which should be a normal variation.
The mechanism of occurrence has not been clarified so far and may be related to the following factors:
Myocardium (30%):
The variation of electrocardiogram repolarization is considered to be due to the fact that part of the ER is not finished in the whole ventricle. The result of early repolarization is more common in the anterior subcardiac myocardium. Therefore, the ST segment shift is marked by V2 to V4. For early repolarization syndrome.
Sympathetic excitability (32%):
Associated with autonomic dysfunction. ERS is more common in healthy young and middle-aged athletes. Most of them have bradycardia, and the ST segment rises more obviously during sleep. However, the use of atropine does not make the characteristic electrocardiogram of ERS disappear. When the exercise or physical stress increases with the heart rate, the ST segment can be reduced to normal or even all ERS features disappear, so it is associated with increased sympathetic excitability and weakened vagus nerve. .
Congenital factors (20%):
It has been reported in China that 7 brothers have familial early repolarization syndrome, and it is not excluded that ERS has congenital factors and genetic factors.
Prevention
Early repolarization syndrome prevention
Because the disease is a normal variation, there is no effective prevention method. In clinical work, attention should be paid to the identification of acute myocardial infarction or variant angina pectoris, otherwise it will cause serious mental threat to the subject.
Complication
Early repolarization syndrome complications Complication
Generally no serious complications occur.
Symptom
Symptoms of early repolarization syndrome Common symptoms Fatigue electrophysiological abnormal palpitations Heart rate increased congenital heart conduction block chest pain dizziness
ERS is a benign congenital heart conduction or electrophysiological abnormality, not a sign of organic heart disease, most without any symptoms, some patients have autonomic dysfunction, vagus nerve predominance, often feel dizzy, palpitations, fatigue , pre-cardiac discomfort, tingling or crushing pain, sometimes can be radiated to the left shoulder, arm, precordial pain is not related to physical stress, nitroglycerin can not be relieved, ERS patients with long-term follow-up X-ray, coronary angiography No obvious abnormalities were found in echocardiography and various laboratory tests.
The electrocardiogram of ERS is similar to organic heart disease. It is difficult to differentiate diagnosis when it is accompanied by obvious chest pain and palpitations. The diagnostic criteria of ERS are based on two or more lead ECGs:
1. The ST segment elevation at the J point of the QRS complex wave is above 0.5 mV.
2. ST segment is raised upwards in concave direction, the site is more common in V3 ~ V5, limb lead can also be raised, but the aVR lead is not elevated.
3. ST segment elevation can last for many years, and there is a downward trend in the increase with age.
4. The R wave branch has obvious notch or blur, similar to the right bundle branch block pattern.
5. The T wave is towering or inverted.
Examine
Early repolarization syndrome examination
Mainly by ECG diagnosis, ECG check ERS features:
1. J wave or J wave appears in the connection between the R wave drop branch and the ST segment. If the J wave is obvious, especially in the V1 ~ V2 lead, the r' pattern can be seen, similar to the right bundle branch block.
2. The ST segment is raised horizontally or downwardly by 0.1 to 0.6 mV, and the elevated ST segment is downward.
3. The ST-segment elevation leads, the T-wave is symmetrically increased, and the ST-segment is merged with the T-wave ascending branch.
4. The R wave of the chest lead rises and the S wave becomes smaller or disappears. The above changes are more common in the V3~V5 lead and can last for many years, but can be changed repeatedly.
5.T wave can be inverted, often in the ST segment of the V3 ~ V5 lead, its characteristics: inverted T wave two asymmetry, periodic changes, sometimes shallow or upright, oral potassium or phenyl The rear of the Lol can be changed to a positive T wave, but the characteristic ST segment of the ERS does not change.
6. Other ECG changes PR (Q) interval shortening, greater than 0.12 s, shorter than 0.14 s; ST-segment elevation leads and II, III, aVF leads can show bimodal P waves, which are intraventricular block Performance; may be associated with supraventricular arrhythmia and atrial fibrillation.
Diagnosis
Diagnosis and identification of early repolarization syndrome
The use of secondary ladder, treadmill or active flat test is a simple and practical method for diagnosing ERS. As the heart rate increases, all or part of the ST segment returns to the same wire, the J wave decreases or disappears, and the T wave rises back to normal or inverted. For erect, combined with clinical symptoms disappeared, can be diagnosed as ERS.
Differential diagnosis
1. Variant angina ERS ECG showed ST-segment elevation, such as with chest pain, easily misdiagnosed as variant angina, but variant angina pectoris showed transient ST-segment elevation, and ST-segment elevation occurred with chest pain episodes. Relieve and disappear, heart rate is faster at the onset, often accompanied by ventricular arrhythmia, ST segment changes in exercise test is not obvious, and can induce ST segment elevation, can be distinguished.
2. Acute myocardial infarction in the acute phase when ERS developed chest pain, ST segment elevation, with T wave high, should exclude the acute acute myocardial infarction, myocardial infarction has obvious chest pain, ST segment elevation is large, and there is a typical ST- During the evolution of T, pathological Q-wave and serum enzymatic curve changes, and there is no difficulty in identification.
3. Acute pericarditis, acute pericarditis produces diffuse injury current, ST-segment elevation is more extensive, more common in I, II, aVF, and V2 ~ V6 lead, similar to ERS, but acute pericarditis ST segment elevation High days or about 1 week can return to normal, ST segment recovery and other wires can appear T wave inversion, often accompanied by increased heart rate and low voltage, auscultation can be heard that pericardial friction sound is different from ERS.
