Heart murmur may be a normal physiological phenomenon, but it cannot be ruled out due to heart valve disease, rheumatic immune disease, myocardial disease, vascular disease, hyperthyroidism and other conditions. 1. Normal physiological phenomenon: when the blood flows from the high-pressure area to the low-pressure area in the process of circulation, a murmur may be formed due to eddy currents, which is a normal physiological phenomenon, and generally does not require special intervention. 2. Heart valve disease: Valve stenosis, valve closure insufficiency and other heart valve diseases will cause the heart to change hemodynamics when beating, which is more likely to cause murmurs. 3. Rheumatic immune diseases: Rheumatic immune diseases such as systemic lupus erythematosus and rheumatic fever will affect the heart valves, which may lead to murmurs in the heart. 4. Myocardial diseases: Myocardial diseases such as cardiac hypertrophy and myocarditis can damage the heart muscle and cause changes in blood dynamics, which can cause a murmur in the heart when the blood is being transported. 5. Vascular diseases: vascular diseases such as hemangioma and coronary artery atherosclerosis can cause the blood flow of the human body to change considerably, which may lead to a heart murmur. 6. Hyperthyroidism: Hyperthyroidism is likely to lead to hyperthyroidism heart disease, which also triggers changes in blood flow and may lead to the development of a heart murmur. After the heart murmur symptoms, you need to go to a professional hospital as soon as possible for examination, so that doctors can analyze the cause of the disease and give patients targeted treatment.