Symptom >> Internal Medicine >> Cardiology

Irregular heartbeat

Introduction
Cause
Examine
Diagnosis

Introduction

Introduction Arrhythmia refers to the number of beats per minute of the heart, whichever is the first. The heart rate of healthy adults is 60-100 beats / min, most of them are 60-80 beats / min, women are slightly faster; children under 3 years old are often more than 100 beats / min; the elderly are slow. Adults have a heart rate of more than 100 beats per minute (generally no more than 160 beats/min) or infants and toddlers over 150 beats/min.

Cause

Cause

1, respiratory sinus arrhythmia: respiratory sinus arrhythmia is the most common type of sinus arrhythmia. It occurs mostly in children, youth and the elderly, and middle-aged people are less common.

2, non-respiratory sinus arrhythmia: non-respiratory sinus arrhythmia is rare, the specific reasons are not very clear, some people think that with anger, emotional instability, or the use of certain drugs (such as digitalis, morphine Etc.)

3, the sinus node within the migratory rhythm: the occurrence of excitement moves within the sinus node.

4, sinus arrhythmia related to ventricular contraction and blood discharge: sinus arrhythmia related to ventricular contraction and blood discharge, is due to abnormal blood supply to the sinus node due to abnormal ventricular contraction and blood discharge, resulting in sinus node Self-discipline has changed.

5, ectopic heart rhythm-induced sinus arrhythmia: ectopic agitation, especially from the atrial ectopic agitation, sometimes the sinus node activation early, followed by inhibition of the sinoatrial node, resulting in a Sinus arrhythmia induced by sexual ectopic activation. Respiratory arrhythmia caused by the enlargement and contraction of the chest during breathing, is common in children and young people, has no pathological significance, does not require treatment, and is also seen in heart patients. Sinus arrhythmia, which is not related to breathing, is more common in elderly and heart disease patients.

Examine

an examination

Related inspection

Cardiovascular dynamic electrocardiogram (Holter monitoring) 64-slice spiral CT examination

1, respiratory sinus arrhythmia: respiratory sinus arrhythmia is the most common type of sinus arrhythmia. It occurs mostly in children, youth and the elderly, and middle-aged people are less common. The mechanism of respiratory sinus arrhythmia is due to the changes in the tension of the vagus nerve and sympathetic nerve in the process of breathing, and the periodicity and regularity of the sinus node self-discipline. When inhaling, the sympathetic tone is increased, the heart rate is increased, the vagus nerve tension is increased during exhalation, and the heart rate is slowed down. The cycle of heart rate changes is exactly equal to one breathing cycle, and the heart rhythm changes to regularity when the breathing is stopped. Its ECG features are as follows:

The 1P wave is the "sinus P wave" issued by the sinoatrial node (positive in the I and II leads, negative in the aVR lead), and its morphology is constant. 2 The rate of heart rate changes with the change of breathing. When inhaling, the heart rate increases. When exhaling, the heart rate slows down. The period of rapid and slow change is exactly equal to one breathing cycle. 3 In the same lead, the difference in RR pitch or PP pitch is more than 0.12 seconds. The 4P R interval is greater than 0.12 seconds.

The 1P wave is the "sinus P wave" issued by the sinoatrial node (positive in the I and II leads, negative in the aVR lead), and its morphology is relatively constant.

The 2P wave frequency change has nothing to do with breathing, and the heart rate sometimes suddenly increases.

3 In the same lead, the difference in PP pitch or RR pitch is more than 0.12 seconds.

The 4PR interval is greater than 0.12 seconds.

3, the sinus node within the migratory rhythm: the occurrence of excitement moves within the sinus node, therefore, the shape, size and direction of the P wave on the electrocardiogram gradually change, the characteristics of the electrocardiogram are as follows:

The 1P wave is a sinus P wave (positive in the I and II leads and negative in the aVR lead).

The 2P wave shape and size change are inconsistent.

The length of the 3P?R interval varies, but it has exceeded 0.12 seconds.

Diagnosis

Differential diagnosis

Atrial fibrillation (AF) is the ectopic tachycardia of the pacemaker at the atria. Irregular impulses of 350 to 600 beats/min occurred in the atria during atrial fibrillation, causing uncoordinated atrial fibrillation. The atrioventricular conduction system can only accept the conduction of partial atrial excitability. Ventricular pulsation is rapid and irregular during atrial fibrillation, between 120 and 180 beats/min. Atrial fibrillation is one of the most common arrhythmias in adults, far more common than atrial flutter, and the ratio of the two is 10-20:1. There are two types of atrial fibrillation: paroxysmal and persistent. The former is more frequent, and the latter lasts for more than a few months. Paroxysmal recurrence can be transformed into persistence.

Atrial flutter (atrial flutter) is an atopic tachycardia that originates in the atria and can be converted to atrial fibrillation. When the atrial flutter occurs, the impulse of the rule of 300 times/min is generated in the atrium, causing a rapid and coordinated atrial contraction. Most rules of the ventricular rhythm (the ratio of atrioventricular conduction is 2-4:1), and a few irregularities (the ratio of atrioventricular conduction is not Uniform), ventricular rate is often between 140-160 beats / min, atrial flutter is also divided into two types of paroxysmal and persistent, the incidence is less than atrial fibrillation.

Pre-excitation is an abnormal phenomenon of atrioventricular conduction. Impulse is transmitted through additional channels, and some or all of the ventricles are excited early, causing some ventricular muscles to be excited in advance. Pre-excitation syndrome (pre-exciTATion syndrome) or WPW (Wolf-Parkinson-White) syndrome, often combined with supraventricular paroxysmal tachycardia. Pre-excitation is a rare arrhythmia, and the diagnosis depends mainly on the electrocardiogram.

Healthy people's exercise and emotional stress can cause tachycardia. Alcohol, tea, coffee and drugs such as isoproterenol and atropine often cause sinus tachycardia. Common diseases in the disease state are fever, hypotension, hypoxia, cardiac insufficiency, anemia, hyperthyroidism, and myocarditis.

The number of heartbeats in normal people is 60-100 beats/min. Less than 60 is called bradycardia. There are several types of bradycardia, the most common being sinus bradycardia. Sinus bradycardia can be divided into pathological and physiological. Physiological sinus bradycardia is a normal phenomenon. The general heart rate and pulse rate are 50-60 beats/min. The athlete may have 40 heart rate. Without treatment, it is common in normal people who sleep and have more physical activity. Heart rate or pulse is less than 50 times. Most of them are pathological and require treatment. In severe cases, a pacemaker should be installed to speed up the heart rate.

Accelerated atrial escape rhythm is common in organic heart disease involving the atria, such as rheumatic heart disease, chronic pulmonary heart disease, pulmonary infection, emphysema, coronary heart disease, myocardial infarction, myocarditis, heart surgery, Digitalis poisoning and systemic infections. Individual cases can be seen in people without structural heart disease, rarely seen in normal people.