Recently, the Internet and WeChat circle of friends have been circulating articles such as “terrible heart stent” and “four sins of heart stent”, which have caused many misunderstandings among the general public and heart patients and their families about heart stent and stent surgery itself, and even many non-cardiac professional medical workers have doubts about this technology, resulting in many patients delaying treatment and causing patients to have various adverse cardiac events. For this reason, as a cardiology professional, the author, in the spirit of scientific rigor and in response to the various questions of patients and families encountered in clinical work, hereby explains cardiac stenting and stenting surgery as follows: 1. In 1977, Andreas Gruenzig, a German physician, performed the world’s first coronary balloon dilation (PTCA) in Switzerland, and in 1984, the first PTCA was performed in China. The first coronary stent was performed in 1986, and drug-eluting stents have been available since 2000. Since then, the technique has been widely used worldwide to improve myocardial ischemia caused by coronary heart disease and myocardial infarction caused by coronary artery blockage. Currently, cardiac stenting is widely used worldwide, with more than 1 million cardiac stenting procedures performed in the United States each year, and the number of cardiac stenting procedures in China currently exceeds 300,000 each year, ranking second in the world. Coronary stent surgery has saved a large number of patients with acute coronary syndromes such as acute myocardial infarction and unstable angina because of its advantages of rapid and durable opening of coronary vessels. Therefore, stenting is not obsolete, but widely used in clinical practice. 2.Does all stenosis require stenting? Many people believe that after coronary angiography, as long as there is stenosis in the blood vessels, doctors will put in stents. There are three main arteries on the surface of the heart that are responsible for the blood supply of the heart itself, which is equivalent to the “oil circuit” of the car engine itself. If the oil circuit is blocked, the engine will not work properly. Coronary artery disease is diagnosed when any of the three main coronary arteries has a stenosis of more than 50% of the trunk, but stenting is generally considered only when the stenosis is ≥70%. Of course, factors such as the number of diseased vessels, whether the stenosis is proximal or distal, and whether the degree of vascular sclerosis allows for stent passage must also be considered. Because the degree of stenosis is in most cases assessed by the clinician with the naked eye, it is somewhat subjective, and there is also some variation in judgment between operators. Therefore, for critical lesions with a stenosis of 60%-70%, it may be necessary to consider implanting a cardiac stent only when the patient has sufficient evidence of myocardial ischemia or when the patient’s clinical symptoms are not well controlled by intensive drug therapy after consultation among multiple physicians and joint development of a surgical treatment plan or evaluation with special devices such as intravascular ultrasound and intracoronary pressure guidewire. 3.Is it better to put a stent or a heart bypass? There are three main treatments for coronary artery disease: drug therapy, interventional therapy (i.e. intravascular stent implantation) and surgical bypass surgery, each of which has its own indications. The next treatment option can be decided after the patient has undergone a coronary angiogram. For patients with coronary artery stenosis <70%, most of them only need long-term oral medication, smoking cessation, control of hypertension, diabetes and other risk factors for coronary artery disease, and improvement of lifestyle, and most of them will not progress quickly in the short term. However, for patients with limited stenosis ≥70%, stenting can be used to relieve coronary stenosis, relieve angina and reduce the risk of myocardial infarction in the future. Stenosis in the left trunk of the coronary artery (equivalent to the root of a large tree), lesions with severe calcification of the blood vessels that are not expected to pass through the stent, and lesions with severe dilatation of the blood vessels or hemangioma require surgical open heart bypass surgery. Therefore, these three treatment methods treat different targets and there is no question of who is better or worse. The clinician will suggest the next step of treatment to the patient or family based on the results of coronary angiography, the patient's systemic co-morbidities and age, economic conditions, etc., but the final decision is up to the patient or family. 4.What is the difference between imported and domestic stents? At present, the domestic drug-eluting stents used in clinical application mainly include brands such as Lepre, Firebird and Axel, but the domestic stents are still the second generation drug-eluting stents. Imported stents include Abbott's Xience series, Medtronic's Resolute series and Boston Scientific's Element series, all of which are third-generation drug-eluting stents. The new generation stents are significantly better than the second generation drug-eluting stents in terms of in-stent restenosis, incidence of late stent thrombosis after stent implantation, stent process, stent visualization effect, and stent passage rate. In terms of price, each imported stent is nearly 7,000-10,000 RMB more expensive than domestic stents. However, the second generation stents have been widely used in China for many years, and their exact efficacy has been widely recognized by clinicians and patients, so the effect of the second generation stents in treating coronary heart disease is not in doubt, and they are still widely used in clinical practice because of their cheaper price. 5.Is coronary heart disease cured after stenting? Some people mistakenly believe that they can't stop taking medicine after stent implantation, and it's fine if they don't have a stent, but they have to take medicine for the rest of their lives after having a stent. For patients who are clearly diagnosed with coronary heart disease by imaging, they should start taking anti-atherosclerotic drugs (such as statin lipid-lowering drugs) and drugs to control blood pressure, blood sugar and other risk factors immediately after diagnosis, and most of the drugs need to be taken for life. Patients with drug-eluting stents need to take a combination of two antiplatelet drugs, aspirin and clopidogrel (trade name Bolivar), for at least one year in order to prevent in-stent thrombosis, and aspirin and statin for life after one year. Therefore, it is not whether or not a stent is implanted that determines whether a patient needs lifelong medication, but rather the nature of the patient's coronary artery disease itself that determines the duration of treatment. It should be emphasized that clopidogrel is a relatively expensive drug, but it is not used only for patients with stents. Patients with unstable angina and myocardial infarction, whether or not stents are implanted, require a period of intensive antiplatelet therapy for a long time. 6. Is there a "life span" for stents? Many patients worry that the stent will "age" after a few years after implantation, and some think that the stent will "break" or "fall off" after a few years. Does a stent have a life span? Pathological studies have found that after stents are implanted in human blood vessels, the stents are completely covered by the endothelium of blood vessels in some patients after about 4 weeks, and the majority of patients completely reach the endothelial cells covering the metal stent trabeculae within 1 year, so that no more metal stent filaments are exposed in the blood, and the probability of stent thrombosis will be significantly reduced. This is also the reason for taking dual antiplatelet drugs for 1 year after stent implantation. After the surface of the stent is completely covered by the new endothelium, the stent becomes part of the vessel wall at this time and plays the role of supporting the vessel, which will accompany the patient for a lifetime, so the stent implanted in the vessel cannot be removed. If the stent is not completely covered by the endothelium in the follow-up imaging 1 year after stenting, it is still necessary to extend the time of taking the above mentioned drugs appropriately. The stent successfully implanted in the body will not fall off either, and patients can move around and participate in various sports without worrying. Moreover, no rejection of the stent by the human body has been found so far. 7.What are the risks of the stenting procedure itself? Strictly speaking, the implantation of a stent in a heart vessel does not require a surgical opening and general anesthesia, so it is not called a surgery, but rather a procedure. After local anesthesia, the surgeon punctures the artery through the skin (at the base of the arm or thigh) and, under X-ray, performs balloon dilation and/or implants a stent into the narrowed or blocked part of the coronary artery through a ballpoint pencil-thin catheter or other device to restore the lumen and reopen the blood flow (see Figure 1). The patient is conscious throughout the operation and generally has no significant spontaneous discomfort. The operative time for common lesions usually takes about 1 hour or more, and postoperative compression of the vascular puncture site is required to stop bleeding for 4-6 hours, and patients with punctured thighs are bedridden for 6-12 hours. Patients are usually discharged from the hospital 1-2 days after the procedure. The risk of death for coronary angiography alone is about 1 in 10,000, and the risk of operative death for patients with implanted stents is about 2 in 1,000. High-risk patients include patients of advanced age, combined with severe cardiac and renal insufficiency and chronic obstructive pulmonary, multiple stenoses in multiple branches of the coronary arteries, and women. In conclusion, cardiac interventional technology represented by cardiac stent implantation is a mature and scientific medical technology that has successfully saved a large number of patients with critical and complex heart disease worldwide and has greatly promoted the progress of medicine. The general public should look at the widespread promotion and use of this new technology scientifically, rationally and objectively, so that the advanced technology can better serve humanity.