Arrhythmia, also called arrhythmia, is an abnormality in the frequency or (and) rhythm of the heart beat. If no treatment is taken, it may lead to shock, heart failure, and sudden death. 1. Shock: When an arrhythmia interferes with normal blood flow, it may lead to inadequate perfusion to vital organs and cause shock. 2. Heart failure: heart failure is a variety of pathogenic factors lead to absolute reduction or relative insufficiency of cardiac output, which cannot meet the metabolic needs of tissues and cells of the body. When arrhythmia affects the function of the heart, it is very likely to lead to heart failure. 3. Sudden death: especially ventricular fibrillation as well as severe conduction block may lead to sudden death of the patient. Arrhythmias can have an impact on an individual’s normal life and require timely consultation with the cardiovascular medicine department of the hospital and treatment under the guidance of the doctor.