Enlargement of the left atrium and left ventricle is usually a diagnostic and qualitative criterion of the heart under color ultrasound and Doppler. This qualitative diagnosis usually signifies that the patient is experiencing one of the following major categories of disease. Common causes are valvular diseases of the heart, such as mitral valve insufficiency, hypertensive heart disease, hypertrophic heart disease, obstructive cardiomyopathy, and aortic valve insufficiency, which can lead to enlargement of both the left atrium and the left ventricle. In addition, dilated cardiomyopathy and ischemic cardiomyopathy can also present with the clinical symptoms described above. When the left heart is enlarged, the patient usually leads to left heart failure, pulmonary bruising, cough, sputum, decreased activity tolerance, in addition, in severe cases, the patient will not be able to lie down, sit and breathe, dizziness, fatigue, and also lead to cardiac arrhythmia, the common arrhythmia, such as atrial fibrillation, atrial flutter and other clinical symptoms.