Patients with myocardial infarction often have some precursor symptoms before the onset of a heart attack, including chest tightness, palpitations, irritability, fatigue, and episodes of angina, among which the angina episodes are most characteristic. This angina can manifest as the first occurrence of angina, or as a worsening of previously experienced angina symptoms. It is characterized by more intense chest pain, longer duration, and often occurs without clear triggers. Nitroglycerin taken sublingually does not fully relieve it. These symptoms should be taken seriously, and it is important to promptly visit the cardiology department of a hospital. Through inpatient treatment, the condition can be stabilized, and many patients can avoid an acute myocardial infarction.