We are not strangers to acute myocardial infarction. Because this acute myocardial infarction is very common and even appears all around us, our loved ones and friends may have had this disease. Acute myocardial infarction has a high cure rate if a clear diagnosis is made in time, otherwise it can be directly life-threatening. To diagnose whether it is an acute myocardial infarction, three conditions are needed: symptoms, electrocardiogram, and troponin. The symptoms of acute myocardial infarction mainly include crushing chest pain with sweating, fear or near-death feeling; the ECG of acute myocardial infarction is simply divided into ST-segment elevation type and non-ST-segment elevation type; troponin (cTn) is currently the most important laboratory index for the diagnosis of acute myocardial infarction (AMI). However, these three conditions do not need to be present at the same time, that is, as long as two of them are present at the same time, the diagnosis of acute myocardial infarction can be confirmed, and interventional, thrombolytic, anti-shock, analgesic, and oxygen therapy can be actively carried out. The diagnosis of acute myocardial infarction cannot be based on any single condition. Among these three conditions, the most easily available are symptoms and ECG, which is not difficult to understand. The reason why patients go to the hospital is that they have symptoms, and the doctor will know when they ask after admission. At the same time, the symptoms of acute myocardial infarction are relatively typical and not difficult to determine. Getting an ECG, too, is relatively simple, that is, it can be done on the way to the hospital, on 120. This way the doctor can determine if it is an acute myocardial infarction based on the symptoms and the results of the ECG, and does not need to wait for the results of cardiac enzymes and troponin. The reason for this is that troponin has two drawbacks: one is that the results are slow and the test usually takes 40 minutes; the other is that troponin, instead of being elevated as soon as there is a myocardial infarction, takes a certain amount of time. Therefore, experienced doctors will not wait for troponin test results to diagnose acute myocardial infarction, as this will delay the treatment. But does this mean that troponin is meaningless for diagnosing acute myocardial infarction? This is not the case, because there is another condition that requires troponin. There is another type of myocardial infarction that is a non-ST-segment elevation myocardial infarction. This type of myocardial infarction is symptomatic, but the ECG does not show it, so troponin is needed to verify it, and this type of myocardial infarction does not require immediate opening of the vessel, so the results can be waited a little to provide stronger evidence for the diagnosis.