Aortic stenosis is caused by rheumatic fever disease for a long time, the main symptoms are left-sided chest pain, dizziness, difficulty in breathing and even sudden death, echocardiography is an important method to diagnose this disease. In normal people, the area of the aortic valve orifice is less than 4 square centimeters, and aortic stenosis is divided into three levels according to the area of the valve orifice as shown by ultrasound. The aortic valve orifice area of 1.5-3 cm2 is mild, the aortic valve orifice area of 1.0-1.5 cm2 is moderate, and the aortic valve orifice area of less than 1.0 cm2 is severe. Mild aortic stenosis may be asymptomatic, sometimes with shortness of breath after exercise. Moderate aortic stenosis may cause irregular chest tightness and shortness of breath. Severe aortic stenosis is more severe and requires surgical treatment such as aortic valve replacement.