After a myocardial infarction occurs, the myocardium cannot return to its original state. Thus, the heart itself also constrains the overall state of the body, and the whole body can no longer return to its original state. Myocardial infarction means the necrosis of myocardial cells. The heart itself loses some of its myocardial function, and after losing part of the myocardium, myocardial remodeling occurs. These changes act as compensation, and through aggressive treatment, the function of the remaining myocardium can be preserved to the greatest extent. If a myocardial infarction occurs, immediate interventional treatment or thrombolytic therapy can prevent myocardial cell necrosis, or even make it minimal. In this case, the heart as a whole is nearly normal, and its function is unaffected. The larger the area of myocardial necrosis, the less remaining function the heart has. If the area affected by the myocardial infarction is relatively small, and with aggressive, long-term treatment, the function of the heart can be preserved to the greatest extent. Thus, the prognosis is generally better. The larger the area of myocardial infarction, the worse the prognosis.