“Transient” refers to a clinical symptom or sign that occurs once or several times in a short period of time, often with an obvious trigger, such as after eating a certain food, taking a certain medication, receiving a certain clinical treatment or other factors that affect the body. This sign or symptom disappears quickly with the removal of the trigger. The systolic murmur is the most common clinical murmur and can be functional or organic, with functional being the most common type of heart murmur. A transient apical systolic murmur may be associated with unstable angina, an acute cardiac event of coronary artery disease, an important component of acute coronary syndrome, and an intermediate clinical syndrome between chronic stable angina and acute myocardial infarction. A transient apical systolic murmur is often diagnosed clinically differently from diastolic murmur. Diastolic murmur is characterized by: ① organic: mainly seen in rheumatic heart valve disease mitral stenosis, auscultation is characterized by a rumble-like murmur in late diastole, incremental, low in pitch, confined to the apical region clearer in left lateral recumbency, often accompanied by diastolic tremor and first heart sound hyperactivity or open valve sound. Relative: Relative mitral stenosis caused by aortic valve incompetence, which is due to increased left ventricular blood volume and increased diastolic pressure caused by regurgitated blood, pushing up the anterior mitral leaflet in a higher position and presenting a relative mitral stenosis. The aortic valve can be closed with a decreasing diastolic sigh-like murmur, which can be differentially diagnosed from organic mitral stenosis based on the above differential points. 2, aortic valve area: mainly seen in rheumatic heart valve disease aortic valve insufficiency and other organic valve lesions, auscultation is characterized by a decreasing sigh-like murmur starting in early diastole, most pronounced in the third intercostal space of the left sternal margin (the second aortic valve auscultation area), can be heard more clearly in sitting position and at the end of expiration with breath held, the murmur is transmitted down the left sternal margin and can reach the apical part. 3, pulmonary valve area: organic lesions are rare, mostly caused by pulmonary artery dilatation pulmonary valve relative insufficiency, producing diastolic murmur, called Graham Steel murmur, common in mitral stenosis, pulmonary heart disease, atrial septal defect, primary pulmonary hypertension, etc.. It is characterized by a decreasing, blowing or sighing diastolic murmur, which is most clearly heard in the second intercostal space at the left edge of the sternum and increases in the third intercostal space when lying down or during inspiration.