If the ventricular rate of atrial flutter is not very fast, the patient usually has no symptoms. If atrial flutter is accompanied by a particularly fast ventricular rate, angina and heart failure can occur, as follows: 1. angina: the symptoms of angina are chest tightness and pain, tightness in the chest for 3-5 minutes each time, sometimes presenting a feeling of pressure and radiating to the back. 2. heart failure: the symptoms of heart failure are dyspnea, palpitations, panic, cough, sometimes inability to lie down, lower limb edema, etc. The condition. The common causes of atrial flutter include rheumatic heart disease, coronary artery disease, hypertensive heart disease, cardiomyopathy, pulmonary embolism, chronic congestive heart failure, mitral stenosis and regurgitation, hyperthyroidism, alcoholism, pericarditis, and other causes. Atrial flutter should be treated for the above causes, and medication may also be considered. In the case of hemodynamic instability, treatment with direct current resuscitation is indicated.