Today, when I talked with a family member who was going to have the surgery, she raised the idea that coronary stents are “time bombs” that she had supposedly seen on WeChat, which made me extremely shocked. Stents have significantly improved the survival rate of patients with heart attack and unstable angina, significantly improved the quality of life of patients with coronary artery disease, and saved the lives of countless patients. However, the exaggerated propaganda for the very few cases of accidents after stent implantation, to the point of “time bomb”, is really biased. Here I will make a specific analysis of several common falsehoods about coronary stents to set the record straight. Wang Qi, Department of Cardiovascular Medicine, Beijing 301 Hospital
1.Sudden death after stenting?
First of all, this is a very, very rare report, the cause of which needs to meet two things at the same time: first, the stent is placed in the left main stem (the location of the source of the coronary artery), and second, acute occlusion (mainly thrombosis) within the stent. The main reason for in-stent thrombosis is still related to inadequate antiplatelet therapy, for the following reasons: first, some patients discontinued the dual antiplatelet drugs (aspirin + clopidogrel) without medical advice, or needed to perform surgical procedures or invasive examinations, and discontinued the antiplatelet drugs without the guidance of a specialist; second, some patients had a poor response to the drugs, especially clopidogrel as a precursor drug, which was found to be resistant in some patients. resistance in some patients, resulting in poor antiplatelet effect; third is the problem of stenting technique and experience. The above problems are now well prevented in experienced cardiac centers, and left main stem stenting is no longer off-limits in the eyes of experienced cardiac interventionalists. Intravascular ultrasound (IVUS) is like the surgeon’s eye reaching into the vessel to accurately determine the size, apposition and entrapment of the left main stem stent. For patients with clopidogrel resistance, effective screening can now be performed by means of thromboelastography and drug genotype testing, and the deficiency of antiplatelet therapy can be effectively prevented by drug doubling or switching to alternative drugs such as tigretol.
Therefore, for open lesions such as left main stem, it is necessary to visit an experienced cardiac center to develop a comprehensive treatment plan, and patients themselves should pay high attention and strictly comply with medical advice, so that the occurrence of sudden death after stenting can be effectively eliminated.
2.Will stenting lead to recurrent stenosis after stenting and cannot be dealt with after restenosis occurs?
This is an old problem. In the last century, the restenosis rate in the stent was as high as 30% in the era of bare metal stent, and the introduction of drug-eluting stent in 2000 effectively solved the restenosis problem for this problem. The drug-eluting stent is an anti-endothelial proliferation anti-tumor drug (rapamycin or paclitaxel) coated on the surface of the original bare metal stent, which can effectively control the occurrence of restenosis in the stent. In case of in-stent restenosis, experienced cardiac centers can analyze the problem and find out the causes, such as risk factor control, anti-platelet drug resistance, de novo atherosclerosis, stent technology, metal allergy, etc., and give targeted treatment advice for different causes. Our interventions include high-pressure post-dilatation balloon dilation, cutting balloon dilation, drug-eluting stent implantation, drug balloon dilation, etc. On the basis of this, we will strengthen risk factor control (see “What kind of people are prone to coronary heart disease? How to avoid coronary heart disease?”) For a very small number of poorly controlled cases (such as metal allergy, coronary artery aneurysmal dilatation, etc.), coronary artery bypass surgery is also an option.
3. Is the stenting procedure risky or painful?
The current complication rate of stenting (PCI) is less than 1%, and it is lower in experienced heart centers. At present, more than 95% of patients in our center are operated through the forearm radial artery approach, which is highly comfortable and allows them to go down immediately after the operation, with little pain and fast recovery after the operation, fully reflecting the characteristics of minimally invasive surgery.
4.Do I need to take medication for the rest of my life after stenting?
Coronary heart disease is a chronic disease, like hypertension and diabetes, which requires lifelong medication, and it is not directly related to whether stents are placed or not, but within one year after stent placement, double antiplatelet (aspirin + clopidogrel) cannot be stopped without authorization. I always advise patients that during this year, they can eat two less meals, but the antiplatelet medication must not be stopped! The risk has been talked about in Article 1.
5, the stent is a foreign body, there is damage to the body or have rejection?
The stent is a metal foreign body, but it has no antigenicity, unlike kidney transplantation and bone marrow transplantation, it is not necessary to take immunosuppressive drugs, and there is no rejection reaction. Drug-eluting stents are routinely covered by endothelial cells within 6 months to 1 year and become part of the body as “bones” within the blood vessels. The absorbable stent, which is still in the clinical trial stage, can be completely metabolized into water and carbon dioxide within two years, which is also the next direction of stent development.
6.How many years can a stent last?
As stated in Article 5, stents become part of the body after being covered by endothelial cells of blood vessels and do not have a service life.
7.Will the stent displace during strenuous activity?
The stents are memory alloy with balloon expansion and release, and the release pressure is routinely above 10 atmospheres (atm), so that the stents are embedded in the vessel wall, and it is impossible to shift after successful release, and I often tell patients that the stents will not move after they are released to participate in bungee jumping, let alone flying and sports activities.
8.Can’t I do MRI after stenting?
This is a problem often encountered after stenting. The current stent is mostly made of nickel-chromium or platinum-chromium alloy, which contains very little iron and will not shift in the magnetic field, and many stent instructions clearly indicate that MRI scans can be safely performed about 1 week after stent surgery.
The key is to strictly grasp the indications for stent implantation, strictly control the entrance barrier, fully weigh the risk-benefit ratio, and develop individualized treatment plans for different patients in order to maximize patient benefits. I will respond promptly to any specific questions you may have.
This article is published with permission from Dr. Wang Qi.