Patients with myocardial infarction often have a history of hypertension, coronary heart disease, and diabetes. They usually experience repeated episodes of angina. After angina, the chest pain persists and cannot be alleviated, often including feelings of chest oppression and pressure. Some patients may also experience nausea, vomiting, and fainting, but most do not have severe vomiting. Some patients, because of inferior wall myocardial infarction or posterior wall myocardial infarction, may develop right ventricular dysfunction, or during the treatment process, due to decreased appetite, may suffer from severe vomiting caused by low potassium and low sodium levels. However, this can generally be corrected through treatment.