Causes of a slow heart rate

Everyone's heart rate is generally different, which is actually related to each person's physical condition. Some people have a fast heart rate, while others have a slower heart rate. This is actually quite normal. However, if a person's heart rate is very slow for a long time, then everyone needs to pay attention to it, as it may be caused by a disease in certain organs of the body. So, what are the causes of a slow heart rate?

The above-mentioned issue may be crucial for ordinary people like us, because no one can guarantee that he or she will not have symptoms of slow heart rate now or in the future. In fact, for most people, it is possible to have a slow heart rate. Well, in response to this phenomenon, let’s talk in detail about the specific reasons for a slow heart rate.

Clinically, there are many causes of slow heartbeat, the most common ones are as follows:

1. Conduction block

Conduction block is caused by lesions in the atrial node or myocardium that prevent the commands sent by the sinoatrial node from being transmitted. Conduction block is divided into three degrees. Grade I is milder and may be asymptomatic. It can only be detected during an electrocardiogram examination. Grade II is that a few commands cannot be transmitted and the patient often has a sense of cardiac arrest. Grade III is the most serious. All commands cannot be transmitted, the heartbeat is 20 to 30 beats per minute, which is very irregular. The patient's subjective symptoms are also very serious and cardiac arrest is possible at any time. Emergency treatment should be carried out in time.

2. Changes in vagal tone

Bradycardia caused by increased vagus nerve tension is common in normal people. Although the heartbeat is slow, it is strong and regular, and not less than 50 beats per minute. The cardiac output does not decrease, and the normal physiological function can be maintained.

3. Changes in sinus node function

The beating of the human heart is directed by the sinoatrial node. The bradycardia caused by lesions in the sinoatrial node itself is clinically called sick sinus syndrome. The heart rate is about 40 beats per minute, and the cardiac output is significantly reduced. The patient will experience a series of symptoms such as dizziness, headache, tinnitus, etc. In severe cases, coma and convulsions may occur. Due to insufficient blood supply to the coronary arteries, patients may experience angina pectoris or even myocardial infarction.

Through the detailed introduction in the above article, most people must have understood the specific causes of slow heart rate. The common causes of slow heart rate generally include: conduction block, changes in vagal nerve tone, and changes in sinoatrial node function, etc. Therefore, understanding the specific causes of slow heart rate is actually very helpful for the treatment of slow heart rate.