Cardiac enzymes have important value in clinical diagnosis of diseases, mainly in the following aspects: 1, diagnosis of acute myocardial infarction, if the patient has severe chest pain, check the ECG ST segment elevation or obvious depression, coupled with abnormal increase of cardiac enzymes, the diagnosis of acute myocardial infarction can be clarified; 2, diagnosis of viral myocarditis, especially in young patients, after cold or diarrhea If symptoms such as chest pain, chest tightness, nausea and vomiting occur, check cardiac enzymes if they are increased, especially if they are more than twice the normal value and the electrocardiogram lacks the dynamic evolution of acute myocardial infarction, be highly alert to viral myocarditis; 3. Monitor the side effects of statins, long-term use of statins, such as Rosuvastatin, Atorvastatin, etc., if unexplained muscle pain occurs, check cardiac Enzymes, especially elevated creatine kinase, can help in the diagnosis of rhabdomyolysis.