What is the abnormality of electrocardiogram?

Abstract: Electrocardiogram refers to the sequential excitement of the pacemaker, atria, and ventricles of the heart in each cardiac cycle. Along with the changes in the bioelectricity of the electrocardiogram, multiple signals are elicited from the body surface through the electrocardiograph. A form of potential change pattern (referred to as ECG). Electrocardiogram is an objective indicator of the occurrence, propagation and recovery process of cardiac excitement. So what is the reason for the abnormal electrocardiogram? The Xiaomian editor will explain in detail the causes of abnormal ECG and the differential diagnosis of abnormal ECG. Let’s find out together! What is the abnormality of electrocardiogram? How to prevent and treat abnormal electrocardiogram

Overview of abnormal electrocardiogram

The electrocardiogram refers to the heart's pacemaker, atrium, and ventricle in each cardiac cycle. Excited one after another, along with the changes in electrocardiogram bioelectricity, various forms of potential change patterns (ECG for short) are elicited from the body surface through the electrocardiograph. Electrocardiogram is an objective indicator of the occurrence, propagation and recovery process of cardiac excitement.

What are the causes of abnormal electrocardiogram?

When arrhythmias, ventricular and atrial hypertrophy, myocardial infarction, myocardial ischemia and other conditions occur, abnormal electrocardiograms will appear. ①Nonspecific Twaveabnormality

②The minimum voltage value at which left ventricular hypertrophy occurs (Minimal voltage criterion for LVH (leftventricularhypertrophy)) may be a variation in the normal range (maynormalvariant); a generally normal electrocardiogram in English prompts: left Slight ventricular hypertrophy with abnormal repolarization (Leftventricularhypertrophywithrepolarizationabnormality).

4. The principle of life after old inferior wall and posterior wall myocardial infarction is to avoid heavy physical activities,

avoid excessive mental stress and irregular life, and avoid prolonged Work continuously. It is necessary to receive regular supervision and guidance from doctors throughout the recovery period; in addition to frequent changes in heart disease, the amplitude and direction of T waves are often affected by endocrine, metabolic and autonomic nervous system activities. For example, when mentally stimulated, T waves can temporarily change from upright to flattened or even inverted. Under normal circumstances, the T wave in the lead with the higher R wave should not be less than 1/10 of the R wave in the lead; the normal T wave shape is mostly obtuse, with long anterior branches and short posterior branches; TaVR is inverted ;TⅠ,Ⅲ,V4～6.

Upright; the upright T wave should be larger than 1/10 of the R wave in the same lead, but TV1 ≤ 0.4mV, TV2 ~ 4 ≤ 1.5mV. Those who are different from this are T wave changes;

5. Low voltage means that among the 6 limb leads, the absolute value of Q, R, and S waves in each lead is lower than 0.5mV. If the absolute values ??of the voltages in five of the leads are all lower than 0.5mV, and the other lead is 0.5mV_0.9mV, it is called low voltage tendency. The appearance of low voltage indicates myocardial disease or systemic obesity.

What are the tests for abnormal electrocardiogram?

1. Atrial hypertrophy: It is divided into left and right atrial hypertrophy or bi-atrial hypertrophy. The electrocardiogram is characterized by P wave abnormality, which is more common in chronic pulmonary heart disease, rheumatic mitral stenosis or various causes. The resulting thickening of the atrial muscle and enlargement of the atrial cavity.

2. Ventricular hypertrophy: It is divided into left and right ventricular hypertrophy or biventricular hypertrophy. The electrocardiogram is characterized by abnormal QRS waves. It is more common in rheumatic heart disease, chronic pulmonary heart disease, congenital heart disease, Ventricular muscle thickening and ventricular cavity enlargement caused by hypertension or various causes.

3. Myocardial ischemia: The electrocardiogram is characterized by ST segment and T wave abnormalities, referred to as ST-T changes, which are seen in chronic coronary artery insufficiency, angina pectoris attacks, etc.

4. Myocardial infarction: divided into acute phase and old phase. The electrocardiogram characteristics of acute myocardial infarction are significant changes in QRS wave and ST-T. In old myocardial infarction, the ST-T mostly returns to normal, leaving only Necrotic Q wave.

5. Arrhythmia: The heart rhythm of a normal person is sinus rhythm, with a balanced rhythm and a frequency of 60 to 100 beats per minute. Arrhythmias occur when there is an abnormality in the sinoatrial node or conduction system, where the heart's excitement originates.

6. Sinus arrhythmia: A sinus heart rate exceeding 100 beats per minute is sinus tachycardia, which is common in exercise or mental stress, fever, hyperthyroidism, anemia and myocarditis. A sinus heart rate lower than 60 beats per minute is sinus bradycardia, which is common in hypothyroidism, intracranial hypertension, the elderly and some drug reactions. The electrocardiographic characteristic of sinus arrhythmia is abnormal P-R interval, which has little clinical significance.

7. Premature contractions: referred to as premature contractions, refer to heart beats that occur before the normal cardiac cycle, and often follow a long interval called a compensatory interval, which is divided into three types: atrial, junctional and ventricular. The electrocardiogram shows P wave, QRS wave and ST-T changes, with complete or incomplete compensatory pauses. Occasional premature contractions can be seen in normal people, but frequent premature ventricular contractions or the formation of bigeminy or tripony are more common in various heart diseases.

8. Ectopic tachycardia: It is divided into two categories: paroxysmal and non-paroxysmal, and is further divided into supraventricular or ventricular tachycardia. In addition to fast frequency and irregular rhythm, The former's electrocardiogram is mostly normal, while the latter's QRS wave is wide and deformed, which is more common in organic heart disease, but may also occur in non-organic heart disease.

9. Flutter and fibrillation: divided into two categories: atria and ventricles. Atrial flutter and fibrillation are ectopic rhythms with a frequency of 250 to 600 beats per minute. The P wave disappears and is replaced by an abnormal "F" wave. It is more common in the elderly with cardiac degenerative changes, hypertension, coronary heart disease, and pulmonary heart disease. , hyperthyroidism, etc. Ventricular flutter and fibrillation are malignant arrhythmias. The patient's life is in danger and must be rescued against the clock.

Differential diagnosis of abnormal electrocardiogram:

1. Acute myocardial infarction: QRS and ST-T wave changes appear on the electrocardiogram, which is caused by the obstruction of the coronary arteries that supply myocardial blood flow. Necrosis may affect life due to arrhythmia, cardiac rupture, and heart failure. Urgent intensive care treatment and observation are required, especially when arriving at the hospital during the golden period. Appropriate drugs and medical treatment should be given early, such as blood clot dissolving drugs, emergency cardiac catheterization, and coronary artery disease. Photography and stenosis of coronary arteries include cardiac catheter dilation and stent placement or emergency coronary artery bypass surgery to avoid further expansion of myocardial necrosis, preserve myocardial function as much as possible, and urgently prevent and treat complications.

2. Old myocardial infarction: Myocardial necrosis has occurred in the past, and the scope may be small or the clinical symptoms are not obvious, especially painless myocardial infarction in the elderly or patients with severe diabetes, so that there are no symptoms of myocardial infarction. Feeling a history of myocardial infarction without knowing it usually indicates a problem with the coronary arteries, and other necessary further examinations and necessary treatment should be done by a cardiologist.

3. Myocardial hypoxia: It may be due to coronary artery stenosis, or other problems such as severe anemia, aortic stenosis, excessive myocardial hypertrophy, hyperthyroidism or drugs, which may cause relatively poor myocardial blood flow or perfusion. For ECG changes caused by insufficient ECG, the cause should be evaluated by a cardiologist as soon as possible. If necessary, further ECG, myocardial blood perfusion photography, echocardiography, cardiac catheterization and other examinations should be carried out to identify whether there is coronary artery disease and other causes of myocardial hypoxia. , and further treatment as needed. The subjects themselves should quit smoking, exercise moderately, reduce fatty foods, lose weight, control blood pressure and blood sugar, etc., in order to reduce the risk factors of coronary atherosclerotic stenosis.

4. Non-specific ST-T changes: Those who have ST or T wave changes on the electrocardiogram but have not yet reached the criteria for myocardial hypoxia may have coronary artery disease, drugs, metabolic diseases, other cardiopulmonary diseases, etc. Caused by the disease, it may also be temporary and have no clinical significance, and the test will appear normal again. Simple electrocardiogram examination cannot make a clear diagnosis. It is recommended that a cardiologist evaluate and analyze the patient based on the patient's disease history, clinical symptoms, risk factors, and other examination conditions, and conduct further examinations if necessary. Especially those with clinical symptoms should go to the hospital for examination immediately. However, if there is no special clinical significance, excessive anxiety or too many invasive examinations should be avoided.

5. Arrhythmia: Normal cardiac electrocardiogram is affected by body deformity, heart conduction axis, chest size, lung disease, obesity, etc. Generally, it beats regularly with a speed of 60 to 100 beats per minute. The so-called arrhythmia is an irregular heartbeat or a change in speed, or the starting point of the heart beat is not initiated by the normal sinus node. It may be a normal physiological phenomenon, or it may be affected by systemic physical diseases, drugs, endocrine, or nervous system. Therefore, the treatment method needs to be determined by the cardiologist according to the individual situation.

6. Sinus bradycardia: The heartbeat rate initiated by the sinoatrial node is less than 60 beats per minute. This may be a normal physiological phenomenon, especially for athletes or general sports people. Young people have abnormal heartbeats at rest. Less than 60 beats per minute is normal. In addition, some people who take drugs, especially those with high blood pressure, take beta-receptor antagonist antihypertensive drugs, anti-Parkinson drugs, digitalis cardiotonic drugs, antidepressants, morphine, etc., which will slow down the heartbeat. This may also occur when the thyroid function is low, the body's body temperature is low, and the brain pressure is elevated. Myocardial hypoxia, myocardial infarction, myocarditis or degenerative sinus node disease in the elderly can also cause slowing of the heartbeat. Therefore, for asymptomatic health check-ups, those with simple sinus bradycardia and no other combined ECG abnormalities, and no clinical symptoms such as dizziness, fainting, or temporary loss of consciousness, especially young and healthy people, may be physiological phenomena. Observation is Can. If you have clinical symptoms or are combined with other ECG abnormalities, you should see a cardiologist for examination.

7. Sinus tachycardia: The heartbeat rate started by the sinoatrial node is more than 100 beats per minute. In healthy people, the heartbeat will slow down when they are under tension, fear, pressure and other emotions, or when exercising. It may be greater than 100. In addition, taking drugs, smoking, coffee and other stimulations will also increase the heart rate. Fever, physical illness, insufficient body fluids, shock, hypoxia, anemia, hyperthyroidism and other non-cardiac diseases can also cause tachycardia. , Heart disease such as cardiostasis heart failure, myocardial hypoxia, myocardial infarction, etc. will also increase the heart rate. Therefore, general health checkers can observe if there are no clinical symptoms. However, if there is a suspected disease, you should see a doctor for further evaluation and examination.

8. Sinus arrhythmia: Under normal conditions, there is a slight difference in the signals released by the sinoatrial node. When the difference is greater than 0.16, it is called sinus arrhythmia.

It is a common phenomenon in young people or children, but it can be affected by drugs such as beta-antagonists, digitalis, and morphine. If this kind of arrhythmia does not change with breathing, you need to pay attention to whether there is an acute physical illness, heart disease or brain disease, especially heart rate changes caused by abnormal brain pressure.

9. Premature atrial contraction: It is called when the heartbeat starting pulse is sent from the atria other than the sinus node instead of the original sinus node. It may appear in normal healthy people, especially when drinking, drinking, etc. Coffee, nicotine, anxiety, tension, and fatigue. However, if clinical symptoms occur and their frequency increases, attention should be paid to whether there is atrial hypertrophy, myocardial hypoxia or infarction, pulmonary embolism, hypoxia (such as smoking), or chronic lung disease, and you should go to the hospital for examination.

10. Sinoatrial node conduction obstruction: P wave but no RS wave appears on the electrocardiogram, which means that the pulse cannot be conducted. It may be caused by athletes, vagus nerve excitement, excessive sensitivity of the cephalic sinus, or coronary artery disease. , acute myocarditis, myocardial lesions, overdose of foxglove or quinine, hyperkalemia, hypercapnia, hypoxia, hypothermia, etc. In the elderly, attention should be paid to whether there is unexplained sinus node chemical disease. Especially for elderly health check-ups, if sinus node conduction obstruction is combined with bradycardia, and if there are clinical symptoms of brain hypoxia such as dizziness, dizziness, falling, and temporary loss of consciousness, severe sinus node disease syndrome should be paid special attention to. (SickSinusSyndrome), cardiac catheterization electrical physiology examination should be performed by a cardiologist and a rhythm regulator should be installed if necessary. For most asymptomatic health check-ups, if there are no special risk factors for coronary artery disease or cardiopulmonary disease, observation and follow-up is the best advice, and there is no need to worry.

11. Polygenic atrial tachycardia: This type of electrocardiogram abnormality is not common in general adult labor health examinations. It usually occurs in the elderly with serious diseases, especially those with chronic obstructive pulmonary disease. If the subject smokes and has obvious cough, sputum, and difficulty breathing, and if the electrocardiogram is abnormal, it is recommended to quit smoking immediately and receive medical treatment. In addition, people with foxglove poisoning, congestive heart failure, coronary artery disease, hypertensive heart disease, hypokalemia, and pulmonary embolism may also have this disease.

12. Ectopic atrial rhythm: Occasionally appears in healthy people, but usually indicates heart disease, especially in patients with heart failure. Therefore, when the subject has this abnormal electrocardiogram and symptoms, it is recommended that the heart Detailed investigation.

13. Atrial fibrillation and atrial flutter: This type of abnormal heart rhythm usually has symptoms of palpitations and is less common in general workers or health check-ups. It generally indicates heart disease, especially in the elderly. Heart diseases that often include atrial fibrillation or fluttering branches include atrial enlargement, valvular heart disease, especially mitral stenosis, coronary artery disease, myocardial infarction, hypertensive heart disease, cardiomyopathy, quinine overdose, WPW Syndrome groups, etc., and occasional paroxysmal atrial fibrillation or flutter disease occurs in pulmonary embolism, severe lung disease, especially acute exacerbation of chronic obstructive pulmonary disease. Occasionally, people without cardiopulmonary disease may develop unexplained atrial fibrillation due to alcohol stimulation. Occasionally, paroxysmal atrial fibrillation may occur due to excessive caffeine, smoking, hyperactivity, excitement, or physical exhaustion. Therefore, anyone with such changes in their electrocardiogram should be carefully examined by a cardiologist as soon as possible to check the cause and provide necessary treatment.

14. Counterclockwise rotation of the heart: It is called when the heart rotates counterclockwise in the chest cavity compared with normal people. It is generally of little clinical significance.

15. The heart axis deviates to the left or right: When there is axis deflection on the electrocardiogram, you should see a cardiologist for necessary examinations, including cardiac ultrasound, exercise electrocardiography, cardiac catheterization, etc. for detailed identification. diagnosis.

16. Atrioventricular conduction obstruction: It is a delay in the conduction of cardiac conduction potential from the atrium through the atrioventricular node to the ventricle. The first-level obstruction can occur when the physiological vagus nerve is strong, which is often the case. And with sinus bradycardia. Inferior myocardial wall infarction and atrioventricular node ischemia, anterior myocardial wall infarction and ventricular septal necrosis, fibrosis or calcification of atrioventricular node degeneration, metabolic disease or tumor infiltration into the atrioventricular node, myocarditis, rheumatic heart Disease, beta-antagonists, foxglove and other drugs can also cause atrioventricular conduction obstruction. The first-level obstruction generally has less impact on cardiac function, and a cardiologist can be asked to identify and analyze potential causes and eliminate them. There are two types of second-grade atrioventricular conduction disorder. The first type is usually caused by drugs, especially digitalis, beta-antagonists, type 1 arrhythmia drugs, and calcium ion blockers such as Verapamil and Diltiazem. Occasionally, It occurs when the vagus nervous system is too strong, but it can also occur when myocardial hypoxia, degenerative conduction system disease, myocardial disease, myocarditis, hypoxemia and recent cardiac surgery, so intensive observation is required to find out the cause. Type II second-degree atrioventricular block must be caused by a pathological disease and will not occur under physiological conditions. It should be monitored immediately with an electrocardiogram monitor and taken care of in a cardiac intensive care unit, and the cause should be actively found. , especially myocardial infarction combined with type II atrioventricular conduction obstruction, close attention should be paid to it and a rhythm regulator should be used immediately if necessary.

In addition, secondary diseases may also occur when infiltrative diseases invade the cardiac potential conduction system, hypertension, myocardial disease, acute myocarditis, syphilitic heart disease, siderosis, congestive heart failure, and cardiac surgery. Type of atrioventricular conduction obstruction.

The third degree of atrioventricular node conduction obstruction, in which the atrium and ventricular potentials are dissociated, mainly occurs in acute myocardial infarction and extensive necrosis of the anterior wall. If such ECG abnormalities are found, a rhythm regulator should be considered. In addition, third-degree atrioventricular node conduction obstruction caused by some cardiac potential conduction system lesions, degenerative infiltration, fibrosis or calcification, degenerative infiltrative or calcification disease, myocardial disease and other factors requires the professional differential diagnosis and diagnosis of a cardiologist. Treatment, some cases require emergency intensive care treatment.

17. Right bundle branch conduction obstruction: due to lesions in the conductive bundle that conducts to the right side of the heart, such as myocardial infarction or hypoxia, myocarditis, infiltrative heart disease (tumor or amyloidosis) , degenerative sclerotic lesions or increased pressure load on the right ventricle due to factors such as acute pulmonary embolism, atrial septal defect causing chronic increased fluid load on the right ventricle, hypertension, heart disease and other heart or lung diseases. However, some young people may have incomplete right bundle branch conduction disorder without any heart disease. Therefore, health check-up for workers, especially young people, can be done first after being evaluated by a cardiologist and then followed up. However, some symptomatic people, older people, those with potential risk factors, hypertension, chronic obstructive pulmonary disease, and coronary artery disease risk factors should have a cardiologist identify the cause and improve living habits and behaviors, control blood pressure, blood sugar, etc., and Other necessary medical treatment.

18. Left bundle branch conduction disorder: Except for a few people, most of this conduction disorder is complicated by heart disease, especially coronary artery disease and various increased pressure loads or body fluids. Left ventricular hypertrophy caused by increased load, primary sclerosis, degenerative conduction system disease, myocarditis, various infiltrative heart diseases, etc. Therefore, if the subject's electrocardiogram finds left bundle branch obstruction, especially before the examination Undiscovered new cases with symptoms such as chest tightness, chest pain, dyspnea, movement disorders, weakness, and fatigue easily, and whose physical examination also shows moist sounds in the lungs, heart murmurs, or other concerns about myocardial hypoxia or heart failure, should be referred to a cardiology department. Perform various examinations such as cardiac ultrasound, exercise electrocardiogram, and cardiac catheterization to evaluate and identify the cause and severity of heart disease and provide necessary treatment. If there are no obvious underlying diseases, regular follow-up is recommended. However, you should quit smoking, lose weight and eat less fatty foods, and control blood pressure, blood sugar and blood lipids to reduce risk factors that affect heart health.

19. Premature ventricular contraction: This type of electrocardiogram abnormality is caused by ectopic potential in the ventricles. Premature ventricular contraction will show abnormal QRS wave changes in the electrocardiogram. It is generally divided into: 0th degree, Premature ventricular contractions; first degree, occasionally occurring alone, less than 30 per hour; second degree, often occurring, more than one per minute; third degree, polymorphic premature ventricular contraction (R-ON-T phenomenon). In healthy normal people or people with mitral valve prolapse, the most common electrocardiogram abnormality is premature ventricular contraction; in addition, mental stress, anxiety, tension, exercise, increasing age, alcohol, coffee, tobacco, pseudo-autonomic stimulants, and anti-arrhythmia Abuse of medications, anesthetics, etc. will increase the incidence of premature ventricular contraction; in addition, hypoxemia, hypokalemia, hypomagnesemia, myocardial hypoxic infarction, myocarditis, myocardial disease, mitral valve prolapse, and other cardiac diseases Valvular disease and congestive heart failure may also occur. Therefore, for generally healthy and asymptomatic young people, if there is no suspicion of a special cause, simple premature ventricular contraction only requires tracking and improving living habits. However, if there is an underlying cause, if there are symptoms or arrhythmias, or if there are other electrocardiographic lesions, or if there is a highly dense premature ventricular contraction, the cause and treatment should be examined in detail, especially if the R-ON-T phenomenon develops into ventricular arrhythmias. The risk of tachycardia or atrial fibrillation should be closely monitored and controlled.

20. Atrial enlargement or hypertrophy: For example, the cause of right atrial enlargement may be tricuspid valve or pulmonary valve regurgitation or stenosis, pulmonary embolism, pulmonary hypertension or chronic lung disease causing pulmonary heart disease. When smoking, chronic cough, dyspnea combined with right atrial hypertrophy on ECG, you should quit smoking as soon as possible. As for the most obvious cause of left atrial hypertrophy is mitral valve stenosis or reflux, others include aortic valve disease, left ventricular hypertrophy, chronic left ventricular failure, etc. Patients with chronic hypertension may cause left ventricular hypertrophy and then left atrial hypertrophy. If high When blood pressure is combined with abnormal electrocardiogram, blood pressure should be controlled more strictly.

21. Ventricular enlargement or hypertrophy: The contraction force of the heart during systole pushes blood into blood vessels and circulates to the whole body or lungs. If the pressure load during long-term systole increases, it will cause the ventricular wall muscles to weaken. Hypertrophy; during diastole, the ventricular cavity receives blood from the atrium. If there is too much blood in the ventricular cavity and the body fluid load increases, it will cause heart enlargement. The performance of ventricular hypertrophy recorded on the electrocardiogram is represented by the increase in the potential electric wave on the electrocardiogram. However, an increase in the QPS wave potential on the electrocardiogram does not necessarily mean ventricular hypertrophy. In addition, it may be because young people are thin and the heart is close to the chest wall, so higher potentials are recorded. Therefore, for those who are suspected of ventricular hypertrophy, it is recommended to undergo further cardiac ultrasound examination to identify the cause and heart function. As for young people without symptoms, in addition to controlling blood pressure, special attention should be paid to whether there is congenital local hypertrophy of the myocardium, because this disease It is easy to develop arrhythmia that may occur suddenly during exercise and lead to sudden death. In addition to hypertension, the causes of left ventricular hypertrophy or enlargement may include aortic stenosis, aortic valve disease, ventricular septal defect, mitral atresia reflux, ductus arteriosus and other diseases.

Among the causes of left ventricular hypertrophy on electrocardiogram during asymptomatic labor health examinations, the most common causes are high blood pressure and thin chest wall, and most of them only need to be tracked. However, if you have chest tightness, chest pain, difficulty breathing, breathlessness while walking, or heart murmur, you should seek further examination and treatment from a cardiologist. Of course, you should stop smoking and control high blood pressure. Right ventricular hypertrophy is rarely found in labor health examinations. The causes may be tricuspid valve insufficiency, atrial or ventricular diaphragmatic defects, pulmonary valve disease, pulmonary embolism, pulmonary hypertension, etc. Special attention should be paid to some chronic lung diseases, such as Chronic obstructive pulmonary disease, pneumoconiosis or other causes of pulmonary localized pulmonary dysfunction caused by smoking lead to an increase in the pressure load output from the right ventricle to the pulmonary artery, causing the ventricular wall muscle of the right ventricle to have rSs characteristics on the V1 chest lead of the electrocardiogram. Hyperplasia, if you have such doubts, you should check for lung disease. In short, when ventricular hypertrophy or enlargement simply appears on the ECG without related symptoms of heart failure or abnormal pulmonary function, it may be due to physiological or physical factors that cause the higher cardiac potential recorded on the ECG, but it may also be due to Potential diseases, so don’t be too anxious first, but you should also discuss the problem appropriately with a cardiologist, or use cardiac ultrasound and other related examinations to confirm whether there is atrial hypertrophy (measuring the thickness of the heart muscle) or enlargement (measuring the heart chambers) size) and evaluate the heart function and heart valve health, and provide appropriate medical treatment according to the cause.

1. Atrial hypertrophy: It is divided into left and right atrial hypertrophy or bi-atrial hypertrophy. The electrocardiogram is characterized by P wave abnormality, which is more common in chronic pulmonary heart disease, rheumatic mitral stenosis or various causes. The resulting thickening of the atrial muscle and enlargement of the atrial cavity.

2. Ventricular hypertrophy: It is divided into left and right ventricular hypertrophy or biventricular hypertrophy. The electrocardiogram is characterized by abnormal QRS waves. It is more common in rheumatic heart disease, chronic pulmonary heart disease, congenital heart disease, Ventricular muscle thickening and ventricular cavity enlargement caused by hypertension or various causes.

3. Myocardial ischemia: The electrocardiogram is characterized by ST segment and T wave abnormalities, referred to as ST-T changes, which are seen in chronic coronary artery insufficiency, angina pectoris attacks, etc.

4. Myocardial infarction: divided into acute phase and old phase. The electrocardiogram characteristics of acute myocardial infarction are significant changes in QRS wave and ST-T. In old myocardial infarction, the ST-T mostly returns to normal, leaving only Necrotic Q wave.

5. Arrhythmia: The heart rhythm of a normal person is sinus rhythm, with a balanced rhythm and a frequency of 60 to 100 beats per minute. Arrhythmias occur when there is an abnormality in the sinoatrial node or conduction system, where the heart's excitement originates.

6. Sinus arrhythmia: A sinus heart rate exceeding 100 beats per minute is sinus tachycardia, which is common in exercise or mental stress, fever, hyperthyroidism, anemia and myocarditis. A sinus heart rate lower than 60 beats per minute is sinus bradycardia, which is common in hypothyroidism, intracranial hypertension, the elderly and some drug reactions. The electrocardiographic characteristic of sinus arrhythmia is abnormal P-R interval, which has little clinical significance.

7. Premature contractions: referred to as premature contractions, refer to heart beats that occur before the normal cardiac cycle, and often follow a long interval called a compensatory interval, which is divided into three types: atrial, junctional and ventricular. The electrocardiogram shows P wave, QRS wave and ST-T changes, with complete or incomplete compensatory pauses. Occasional premature contractions can be seen in normal people, but frequent premature ventricular contractions or the formation of bigeminy or tripony are more common in various heart diseases.

8. Ectopic tachycardia: It is divided into two categories: paroxysmal and non-paroxysmal, and is further divided into supraventricular or ventricular tachycardia. In addition to fast frequency and irregular rhythm, The former's electrocardiogram is mostly normal, while the latter's QRS wave is wide and deformed, which is more common in organic heart disease, but may also occur in non-organic heart disease.

9. Flutter and fibrillation: divided into two categories: atrium and ventricle. Atrial flutter and fibrillation are ectopic rhythms with a frequency of 250 to 600 beats per minute. The P wave disappears and is replaced by an abnormal "F" wave. It is more common in the elderly with cardiac degenerative changes, hypertension, coronary heart disease, and pulmonary heart disease. , hyperthyroidism, etc. Ventricular flutter and fibrillation are malignant arrhythmias. The patient's life is in danger and must be rescued against the clock.

How to prevent and treat abnormal electrocardiogram?

"Sinus arrhythmia" is the most common arrhythmia, which is caused by the signals from the sinoatrial node not being completely regular. However, most of this "arrhythmia" belongs to "respiratory sinus arrhythmia", which is a normal physiological phenomenon. Its characteristic is that it changes with the change of breathing. The heart rate can increase by a few beats when inhaling, and can increase by a few beats when exhaling. When breathing, you can slow down a few beats, and the speed cycle is exactly equal to one breathing cycle. When you hold your breath, the heart rhythm becomes regular. This "sinus arrhythmia" that changes with breathing is completely normal and does not require worry or treatment.

Therefore, people who are diagnosed with "sinus arrhythmia" can pay attention to whether there is any relationship between the acceleration and deceleration of their heart rate and their breathing. As long as there are no other symptoms, no treatment is needed and you can go about your normal study and life.

In addition, factors such as mental stress may also cause "sinus arrhythmia", which does not require treatment.