The main causes of acute arterial embolism are arterial emboli, thrombi, or other types of emboli, which can be blood clots, air, tumor cells, fat particles, or intravascular foreign bodies. The most common source of emboli is of cardiac origin, and thrombi from the heart account for more than 80% of acute arterial embolism. The most common lesion of the heart is rheumatic heart disease or bacterial endocarditis, and in rheumatic heart disease combined with atrial fibrillation or mitral stenosis, the calcium fragments of the calcified valves are shed to disrupt blood flow and slow down the flow rate to form thrombi easily. Other heart diseases that cause thrombosis include myocardial infarction and cardiomyopathy, so the most common source of acute arterial thrombosis and emboli is of cardiac origin.