What causes premature beats and how to check them?

The beating of the heart is a normal phenomenon, because the human heart must beat. If the heart does not beat, it will cause life problems. The normal beating of the heart is a normal phenomenon, but if the heart has premature beats, the harm will be very great. Sudden excitement or serious heart disease, such as excessive smoking, drinking or strong tea, may cause premature beats. Such patients need to use electrocardiogram and local heart function tests to find the correct cause.

1. It is caused by excessive excitability of a certain part of the heart. If there is a premature beat caused by excessive excitability in the atrium, it is called atrial premature beat; if there is a premature beat caused by a higher excitability point in the atrioventricular node or ventricle, it is called atrioventricular nodal or ventricular premature beat.

2. Electrocardiography can distinguish it. Premature beats are very common in normal people. If normal people are observed continuously for 24 hours using electrocardiogram, 70% to 80% of them may be recorded with premature beats. Although premature beats are irregular beatings of the heart, not all premature beats are caused by disease.

3. Tension, excitement, anxiety, excessive smoking, drinking large amounts of alcohol, drinking strong tea, and even constipation can all cause premature beats. But most people have no discomfort symptoms, or just feel a "swinging" or twisting sensation in their heart. Frequent premature beats usually cause people to feel discomfort such as palpitations, chest tightness, fatigue, etc.

Many diseases can cause premature beats: patients with non-heart diseases such as hyperthyroidism, anemia, hypokalemia, fever, etc. may experience premature beats.

What are the methods for checking premature beats? Let’s take a look at the following introduction!

Electrocardiogram:

1. Atrial premature beats.

2. Premature beats at the atrioventricular junction.

3. Ventricular premature beats. There is a premature QRS complex with abnormal morphology, mostly lasting ≥ 0.12 seconds, the T wave is opposite to the main wave of the QRS complex, the ST segment shifts in the direction of the T wave, there is no related P wave in front of it, and there is a complete compensatory interval. Premature ventricular beats can occur between two sinus beats, forming intercalated premature ventricular beats.

4. Multifocal premature beats.

5. Parallel rhythm type premature beats. The pattern of premature ventricular beats can help diagnose myocardial infarction.

[ECG manifestations]

The common ECG feature of premature beats is one or more P-QRS complexes that are earlier than the basic heart rhythm.

(A) The P wave of atrial premature beat appears early, and its shape is different from the P wave of the basic heart rhythm, with a PR interval of 0.12S. QRS waves are mostly the same as those of sinus rhythm, sometimes slightly widened or deformed, accompanied by corresponding changes in ST and T waves, which is called intraventricular differential conduction and needs to be distinguished from ventricular premature beats. When atrial premature beats are accompanied by intraventricular aberrations, an early and abnormal P' wave can be seen before the abnormal QRS complex. A premature abnormal P' wave may not be followed by a corresponding QRS wave, which is called a blocked atrial premature beat.

It needs to be differentiated from sinus arrhythmia or sinus arrest. If an abnormal premature P' wave is found on the ST segment or T wave of the previous heart beat, it can be diagnosed as atrial premature beat due to block. Atrial premature beats often invade the sinoatrial node, causing it to depolarize prematurely. The sinoatrial node then spontaneously depolarizes and restarts the original cycle, forming an incomplete compensatory interval. Occasionally, a complete compensatory interval is seen after atrial premature beats.

(ii) Ventricular premature beats: The QRS complex appears early with abnormal morphology, with a duration of mostly 0.12 seconds. The T wave is in the opposite direction to the main QRS wave, and the ST wave is displaced with the T wave, with no P wave preceding it. When ventricular premature beats occur proximal to the bundle branch, their QRS complex may not be widened. Most ventricular premature beats are followed by a complete compensatory pause. When the basic heart rhythm is slow, ventricular premature beats may be inserted between two sinus beats, forming insertional ventricular premature beats. Occasionally, a retrograde P' wave is seen in which a ventricular premature beat is conducted back to the atrium and often appears on the ST segment of the ventricular premature beat.