What Is Bradycardia?

Bradycardia, also known as bradycardia, is an important type of arrhythmia. The heart rate of a normal adult is between 60 and 100 beats per minute. If it is less than 60 beats, it is called bradycardia. Some patients usually have a basal heart rate that is slow, about 50 to 60 times per minute, or even less than 50 times. They usually have symptoms of dizziness, fatigue, burnout, and poor mentality. Some patients usually show normal heart rate, bradycardia can suddenly appear, drop below 40 times per minute, dizziness, transient dark eyes, fatigue, palpitations, chest tightness, shortness of breath, and sometimes a sense of shock in the precardiac area, serious Can occur syncope. There are also some patients with dizziness, fatigue, syncope, and a long-term cardiac arrest with intermittent heartbeat. For bradycardia, if the patient's symptoms cannot be reversed after actively correcting the reversible primary cause and excluding the effects of the drug, a pacemaker needs to be placed.

Basic Information

nickname

Bradycardia

English name

bradycardia

Visiting department

Cardiology

Common causes

Sinus bradycardia, sinus arrest, sinoatrial block, atrioventricular block, or sinus node syndrome, acute myocardial infarction, hypothyroidism, increased intracranial pressure

Common symptoms

Dizziness, fatigue, burnout, poor mentality, etc.

Causes of bradycardia and common diseases

The most common causes of bradycardia are pathological sinus bradycardia, sinus arrest, sinoatrial block, and atrioventricular block. Can also be seen in sick sinus node syndrome, acute myocardial infarction, hypothyroidism, increased intracranial pressure or the use of drugs that slow heart rate.

Systemic disease

Influenza, typhoid fever, hypothyroidism, diphtheria recovery period, obstructive jaundice, increased intracranial pressure, certain infections such as leptospirosis, infectious mononucleosis, hypopituitarism, hyperkalemia, alkalosis , Esophageal diverticulum, depression, can cause sinus bradycardia.

2. Drug

Some drugs like beta-blockers, reserpine, lidocaine, amiodarone, guanethidine, morphine, digitalis, quinidine, verapamil, neostigmine, anesthetics, etc. Can cause sinus bradycardia.

3. Cardiovascular disease

Acute myocardial infarction, myocarditis, endocarditis, pericarditis and sinoatrial node, chronic ischemic heart disease, sinoatrial node inflammation, thrombus, dilatation, inflammation of sinoatrial node artery, certain cardiomyopathy such as amyloidosis After tetralogy of Fallot or macrovascular dislocation, microorganisms affect the heart, bleeding enters the sinoatrial node, familial sinus bradycardia, central nervous system disease involving the heart's inhibitory center or accelerating center, etc., can cause cardiac tachycardia It happened slowly.

Bradycardia differential diagnosis

Distinguish from arrhythmia. Arrhythmia is a pathological phenomenon of abnormal heart pulsation due to heart disease. Occurs in children, youth and the elderly, and is rare in middle-aged people. The mechanism of respiratory sinus arrhythmia is that during the breathing process, the tension of the vagus nerve and sympathetic nerve in the body changes, which causes the periodicity and regularity of the sinus node self-regulation. The sympathetic nerve tension increases during inhalation, and the heart rate increases, while the vagal tension increases during exhalation, and the heart rate becomes slower. The period of fast and slow change in heart rate is exactly equal to one breathing cycle. When you stop breathing, your heart rhythm becomes regular.

Bradycardia

Cardiac auscultation, electrocardiogram, etc.

Bradycardia treatment principles

In the acute episode of bradycardia, in addition to treating the underlying cause and discontinuing drugs that can slow the heart rate, atropine and isoproterenol can be used to increase the heart rate. For patients with a heart rate of 40 beats per minute or slower, the effect of the drug on improving heart rate is not obvious, especially in patients with repeated syncope or precursors to syncope, a pacemaker should be placed.