Valve thickening is mainly caused by heart valve disease. Heart valve disease is a type of heart disease in which the heart valves lose their one-way valve function due to thickening, deformation, adhesion, calcification and rupture. Heart valve disease can cause stenosis or insufficient closure of the heart valves so that the blood cannot flow through smoothly or backs up after it has flowed. Those who cannot flow through smoothly are called valvular stenosis, and those who back up after the blood has flowed are called valvular insufficiency. The most common is mitral valve lesions, followed by aortic valve lesions. Differential diagnosis of valvular thickening: 1. Hypertrophic obstructive cardiomyopathy. Also known as idiopathic hypertrophic subaortic stenosis (IHSS), systolic murmur can be heard in the fourth intercostal space of the left sternal border, systolic clicks are rare, and the second heart sound of the aortic region is normal. Echocardiography showed asymmetric hypertrophy of the left ventricular wall, marked thickening of the interventricular septum, and the ratio of the posterior wall of the left ventricle ≥ 1.3, systolic septum anterior displacement, left ventricular outflow tract narrowing, which can be accompanied by mitral valve anterior leaflet to the cross displacement and cause mitral regurgitation. 2.Aortic dilatation. Aortic dilatation is caused by various reasons such as hypertension and syphilis. A short systolic murmur can be heard in the second intercostal space at the right edge of the sternum, and the second heart sound in the aortic region is normal or hyperactive, with no splitting of the second heart sound. Echocardiography can clarify the diagnosis. 3.Pulmonary stenosis. The second rib interval at the left edge of the sternum and the rough and loud systolic murmur, often accompanied by systolic clicks, the second heart sound of the pulmonary valve area is weakened and split, the second heart sound of the aortic valve area is normal, the right ventricle is hypertrophied, and the main trunk of the pulmonary artery is stenotic and then dilated. 4. Tricuspid valve insufficiency. A high-pitched holosystolic murmur is heard at the lower end of the left sternal border, which is augmented by an increase in the volume of return blood during inspiration and attenuated during whoosh. The jugular veins were pulsatile and the liver was enlarged. The right atrium and right ventricle are markedly enlarged. Echocardiography can confirm the diagnosis. 5. Mitral valve insufficiency. A full systolic wind-blowing murmur in the apical region is transmitted to the left axilla; the murmur is weakened by inhalation of isopentyl nitrite. The first heart sound is weakened, the second heart sound of the aortic valve is normal, and there is no calcification of the aortic valve.