Mitral stenosis, due to fibrosis and/or calcium deposits, extensive leaflet thickening, adhesions, fusion of tendons, shortening, and leaflet stiffness, leads to deformation and stenosis of the valve orifice, which becomes a slit-like hole when stenosis is significant. According to the degree of lesion, there are septal and funnel types. The septal type has no or mild lesions in the main valve body and is still mobile; the funnel type has significant leaflet thickening and fibrosis, significant adhesions and shortening of the tendon cords and papillary muscles, stiffening of the entire valve in a funnel shape, and significant restriction of movement. It is often associated with varying degrees of incomplete closure. Stenosis is further aggravated by leaflet calcification and can lead to thrombosis and embolism. In congenital mitral stenosis, there is leaflet thickening, junctional fusion, tendon thickening or shortening, papillary muscle hypertrophy or fibrosis, and there may be a stenotic annulus above the valve and a fibrous band below the valve. The most characteristic feature is a parachute deformity of the mitral valve with only one papillary muscle, where the tendons of both leaflets are attached to the papillary muscle and the entire valve is shaped like a parachute. Symptoms The earliest symptom is nocturnal paroxysmal dyspnea, and in severe cases, seated breathing; in very severe cases, pulmonary edema, coughing, coughing pink frothy sputum, mostly aggravated after sleep or activity, may be accompanied by coughing sputum, blood in the sputum, hemoptysis. Signs Mitral valve facies, mild cyanosis of mouth and lips. The precordial region is elevated, a fine diastolic tremor can be palpated in the apical region, and the cardiac border is enlarged to the left at the third intercostal space. The apical s1 is hyperactive and tapping, and the open tapping sound can be heard from the left sternal margin at intercostal interval III-IV to the superior apical end. The apical region can be heard in the middle and late diastolic rumble-like murmur, which is incremental and more pronounced in the left lateral recumbent position, at the end of breathing and after activity; the pulmonary valve p2 sound is hyperactive with splitting; the short early diastolic splash-like murmur is heard in the left sternal margin of the pulmonary valve region between the Ⅱ and Ⅲ intercostal spaces, (graham-steell murmur) strengthening upon deep inspiration. Auxiliary examination 1. The earliest change on X-ray examination is the left atrial arc of the left heart margin is obvious, the main trunk of the pulmonary artery is prominent, and the pulmonary veins are widened. In severe lesions, the left atrium and right ventricle are significantly enlarged, and the posterior anterior radiograph shows a double shadow on the right edge of the cardiac shadow, a deepened hilar shadow, and a smaller aortic arch. The left ventricle is generally not large. The Kerley B line is visible in the middle and lower lungs when the left atrial pressure reaches 2.7 kPa (20 mmHg). Iron-containing heme deposits after prolonged pulmonary stasis may appear as scattered punctate shadows in both lower lung fields. Mitral valve calcification is often seen in elderly patients, and is not uncommon in young adults. 2.Electrocardiogram may be normal in mild mitral stenosis. The characteristic change is the widening and bimodal shape of the P wave, suggesting an enlarged left atrium. In combination with pulmonary hypertension, the right ventricle is enlarged and the electrical axis is right deviated. Atrial fibrillation is often combined in the advanced stage of the disease. Echocardiography is the most sensitive and specific noninvasive diagnostic method, which is of great value in determining the orifice area and transvalvular pressure gradient, determining the extent of the lesion, deciding on the surgical approach, and evaluating the efficacy of surgery. The anterior and posterior leaflets of the mitral valve are seen to have increased reflection, thickened, and reduced activity on 2D echocardiography, with the anterior leaflet body expanding forward in diastole in a balloon shape and the distance between the anterior and posterior leaflets of the valve cusps significantly shortened and the opening area reduced. The anterior mitral leaflet and the posterior leaflet are subordinate to the anterior leaflet in diastole, which is known as a city stack. The left atrium is enlarged, the right ventricle is enlarged and the right ventricular outflow tract is widened. Doppler ultrasound shows slow and decreasing flow through the mitral valve. The Doppler ultrasound shows a slow and decreasing flow through the mitral valve. 4. Radionuclide examination of the radionuclide blood pool shows enlargement of the left atrium, prolonged concentration and passage time of the visualizing agent, and the left ventricle is not large. In pulmonary hypertension, enlargement of the main pulmonary artery and right ventricle is seen. 5, right heart catheterization right ventricle, pulmonary artery and pulmonary capillary pressure is increased, pulmonary circulation resistance is increased, and cardiac output is reduced. The pressure in the left atrium and left atrium can be measured directly after puncturing the interatrial septum. The transvalvular pressure step difference is normal in the early diastolic phase of mitral stenosis, and increases as the condition worsens. The diagnosis of mitral stenosis can be made by finding a rumbling diastolic murmur in the apical region with left atrial enlargement, and echocardiography can clarify the diagnosis. Clinically, mitral stenosis should be differentiated from the diastolic murmur in the apical region in the following cases: 1. Acute rheumatic heart disease has a high-pitched, soft early diastolic murmur in the apical region, which varies widely from day to day and can disappear after rheumatic activity is controlled. This is due to the enlargement of the ventricle and the relative stenosis of the mitral valve, i.e., the Carey-Coombs murmur. 2, “functional” mitral stenosis is seen in various causes of left ventricular enlargement, mitral orifice flow increases, or mitral valve in the ventricular diastole by the impact of the aortic regurgitant blood, such as a large number of left to right shunt arteriovenous catheter failure and ventricular septal defect, aortic valve closure insufficiency, etc., this murmur is short-lived, no open sound The nature of the murmur is softer, the murmur is reduced by inhalation of isoamyl nitrite, and the murmur is strengthened by the application of pressure-raising drugs. Left atrial mucinous tumor is the most common primary tumor in the heart. Clinical symptoms and signs are similar to mitral stenosis, but are intermittent and change with body position, generally no opening sound but tumor fluttering sound can be heard, atrial fibrillation is rare and easy to have repeated peripheral artery embolism. Echocardiography shows a cloudy echogenic sound wave in both systole and diastole behind the mitral valve. Cardiac catheterization shows markedly elevated left atrial pressure, and selective angiography shows a filling defect in the left atrium. The latter is now used sparingly because of the possibility of promoting dislodgment of the tumor embolus. A low-pitched rumble-like diastolic murmur is heard at the lower left border of the sternum in tricuspid stenosis, which may be enhanced during inspiration and diminished during expiration due to an increase in regurgitant volume. The jugular vein a-wave increases in sinus rhythm. In mitral stenosis, the diastolic murmur is located in the apical region and does not change or diminish during inspiration. Echocardiography can make a clear diagnosis. 5.Primary pulmonary hypertension occurs mostly in female patients without diastolic murmur and open valve sound in the apical region, no enlargement of the left atrium, normal pulmonary artery artery insertion pressure and left atrial pressure.