Comprehensive Analysis of Eight Common Questions about Coronary Stents: Preoperative Knowledge and Scientific Answers

Frequently Asked Questions about Coronary Stents (Pre-operative):

Question 1: Should a stent be implanted if coronary artery stenosis is >75%? Many patients discover during physical examinations that their coronary artery stenosis is >75%, and some may tell you that you need a stent. This is incorrect.

Currently, the standard for stent implantation does not solely rely on the degree of stenosis, but rather on whether the patient has evidence of myocardial ischemia, such as a positive treadmill stress test, chest tightness after activity, ST segment depression or elevation on ECG with dynamic changes, or intraoperative FFR (fractional flow reserve). If the patient has no evidence of ischemia and examinations indicate stable plaque, even if the stenosis reaches 80%, a stent is not necessary.

If coronary artery stenosis is 90%, and there are clear symptoms of chest tightness and myocardial ischemia after activity, a stent is necessary. Without treatment, long-term myocardial ischemia can lead to cardiac hypertrophy, heart failure, and other symptoms, commonly known as ischemic cardiomyopathy. Once heart failure occurs, the heart suffers irreversible damage; in severe cases, patients cannot function normally, and even at rest, they may experience chest tightness, shortness of breath, and difficulty breathing. In addition, symptoms of myocardial ischemia also indicate unstable plaque in the blood vessels, suggesting a potential for myocardial infarction.

Therefore, if a patient's blood vessel stenosis is >75% and they have clear symptoms of myocardial ischemia, stent implantation is necessary to prevent further myocardial damage.

Question 2: Can medication dissolve narrowed blood vessels? Coronary artery stenosis is the result of long-term formation; no medication can dissolve the plaque. Medication can only slow down plaque growth.

Question 3: Is coronary artery interventional surgery safe? Many patients are afraid when they see the consent form for coronary stent surgery because it lists various potential risks, such as blood vessel rupture, malignant arrhythmias, and sudden death. In reality, the greatest risk of stent implantation comes from the disease itself, such as acute myocardial infarction, which carries a high risk of sudden death. Not implanting a stent would be even more dangerous. Actually, the probability of patients experiencing the above complications after coronary stent surgery is very low. However, doctors will explain all possible risks, even those with only a one in ten thousand chance, to the patient before the procedure; this is the doctor's responsibility.

Question 4: I heard that after stent implantation, I have to take a lot of medication and can't stop.

After stent implantation, because it takes about a year for the vascular endothelial cells to completely encapsulate the stent within the blood vessel, three medications must be taken: aspirin (long-term), clopidogrel or berinda (this medication only needs to be taken for one year), and statins (long-term). Other medications are taken according to the patient's condition. If a stent is not implanted, the above medications should be taken even more consistently, and plaque can change at any time, posing a constant risk to the patient's life.

Question 5: Does coronary angiography necessarily require stent implantation?

Coronary angiography is a minimally invasive examination technique that can clearly show the degree of narrowing in a patient's coronary arteries. If the narrowing is severe, the doctor will explain the condition to the family and the patient. If the family agrees, a stent can be implanted directly. However, if the narrowing is not severe, or if the family does not agree to stent implantation, then coronary angiography is just an examination.

Question 6: Will the blood vessel wall become thinner after stent implantation?

Plaque causes blood vessel narrowing, much like a coal mine collapse; the stent opens the blood vessel, similar to re-supporting and fixing a collapsed coal mine. It has no effect on the thickness of the blood vessel wall.

Question 7: Does a stent have an expiration date?

Stents do not have an "expiration date"; once placed in the body, they can be used for life.

However, whether restenosis will occur at the stent site depends on the patient's risk factors (hypertension, hyperlipidemia, hyperglycemia, smoking, excessive alcohol consumption, lack of exercise, obesity, etc.). Therefore, patients must control their diet, exercise regularly, relax, and take medication on time to prevent restenosis at the stent site.

Question 8: Is stent surgery performed in the arm or the leg?

Generally, stent implantation is performed via the upper limb, meaning the surgery is done in the arm. This method has less impact on the patient, faster recovery, simpler hemostasis, and allows for immediate post-operative mobility. Therefore, hospitals typically perform the surgery in the upper limb. However, sometimes patients have tortuous or malformed blood vessels in their upper limbs, or need to use special instruments with larger diameters, so it is necessary to choose the lower limbs for surgery. Because the blood vessels in the lower limbs are larger and under greater pressure, a vascular suture device may be needed to help stop the bleeding after the surgery.