The causes of murmurs in the heart include the following: 1) Accelerated blood flow, including hyperthermia, hyperthyroidism, and severe anemia.2) Stenosis of the heart valve orifices, including mitral stenosis, aortic stenosis, and pulmonary stenosis.3) Incomplete closure of the heart valves.4) Abnormal blood flow pathways, such as congenital heart disease, ventricular septal defect, and arterial ductus arteriosus.5) Abnormal structure of the heart chambers, such as acute myocardial infarction, papillary muscle rupture, and torn tendons.6) Large vessel aneurysm-like dilatation. For example, acute myocardial infarction, papillary muscle rupture, tendon cable rupture, etc.6. Aneurysmal dilatation of large blood vessels, in which blood flows through the aneurysm, vortexes are formed and sound is produced.