Insufficient blood supply to the heart is dangerous, but the description of insufficient blood supply to the heart is very general. If insufficient blood supply to the heart is found, patients will usually experience symptoms such as chest tightness, chest pain, panic attacks, or shortness of breath when exercising or exerting themselves. The most common cause of insufficient blood supply to the heart is coronary heart disease. If the narrowing of the heart vessels is very serious, indicating that the insufficient blood supply to the heart is also very serious, this situation is very dangerous, the patient may have myocardial infarction or sudden death. Long-term progression may also lead to ischemic cardiomyopathy, which in turn leads to heart enlargement and heart failure, which is a dangerous condition.