The diagnosis of acute myocardial infarction can only be confirmed by ECG, because there are two basic conditions of myocardial infarction: the first is an ECG with specific manifestations, i.e., ST-segment elevation type of infarction can be confirmed by ECG. The second type is called non-ST-segment elevation myocardial infarction, and the diagnosis is confirmed by the ECG combined with the patient’s symptoms and myocardial markers from blood tests. Therefore, the diagnosis of myocardial infarction is not only confirmed by ECG, but most of them are also combined with clinical symptoms. Once a myocardial infarction is detected, emergency coronary angiography is the most fundamental test. For myocardial infarction, ECG can confirm the diagnosis in some patients, while some other patients need dynamic ECG observation and myocardial enzymes for determination. In most cases of myocardial infarction, the patient may have an emergency coronary angiogram, which can be managed directly after the diagnosis is confirmed.