What is a heart attack precursor?

The symptoms of myocardial infarction include chest tightness, poor breathing, shortness of breath, fatigue, palpitations, toothache, stomachache, back pain, etc. When myocardial infarction attacks, there will be chest pain, dying feeling and other symptoms. If not treated in time, it will lead to cardiac arrest. If there is a precursor of myocardial infarction, it is best to go to the Department of Cardiology of the local 3A hospital in time for treatment, and use vasodilator drugs according to the doctor's advice.