Drug-eluting stents, once thought to increase heart attack risk, are generally considered safe if used properly.
By Mayo Clinic Staff
Stents are used to keep arteries open after a procedure called angioplasty. Some researchers were worried about a popular type of stent that slowly releases medication over time (drug-eluting stents). The concern was that drug-eluting stents might increase a person's risk of having a heart attack compared with having a bare-metal stent placed in an artery.
However, since these concerns surfaced, a number of studies have shown that drug-eluting stents are safe and a good option for many people. Find out the differences between drug-eluting stents and bare-metal stents, what you should ask your doctor before having a stent placed, and what you should do after you get a drug-eluting stent.
Stents are metal mesh tubes inserted during angioplasty. Angioplasty is a catheter procedure that involves temporarily inserting and blowing up a tiny balloon where your artery is clogged to help widen the artery. Stents help prevent restenosis — a situation where the artery becomes blocked again. Without the use of stents, about 30 percent of arteries become blocked again.
There are two basic kinds of stents: bare-metal stents and drug-eluting stents.
- Bare-metal stents are metal stents with no special coating. Bare-metal stents act as simple scaffolding to prop open blood vessels after they're widened with angioplasty. As the artery heals, tissue grows around the stent holding it in place. However, sometimes an overgrowth of this scar tissue in the arterial lining increases the risk that the artery will become blocked again.
- Drug-eluting stents are coated with medication that is slowly released (eluted) to help prevent the growth of scar tissue in the artery lining. This helps the artery remain smooth and open, ensuring good blood flow through it. Drug-eluting stents were developed because in some people who get bare-metal stents, tissue growth over the stent eventually leads to re-blockage.
Many people with heart problems have been successfully treated with drug-eluting stents, preventing the need for more-invasive procedures, such as coronary artery bypass surgery. The reduced risk of re-narrowed arteries from drug-eluting stents reduces the need for repeat hospitalization and angioplasty procedures — each of which carry some risk of complications including heart attack and stroke.
Drug-eluting stents are just one option for treating narrowed heart arteries. It's worth remembering that you basically have four options if your arteries become narrowed, each with risks:
- Medications and lifestyle changes. This is a good option for many people. If you have symptoms from your narrowed coronary arteries, such as angina, and your condition isn't severe or immediately life-threatening, it may be worth first trying medications, such as beta blockers, nitrates, calcium channel blockers, aspirin and statins. In addition to medications, lifestyle changes, such as stopping smoking, eating a more balanced diet and exercising, can be as effective as receiving a stent in some circumstances. Keep in mind that even if you receive a stent, your doctor will likely also prescribe medications, such as statins, and lifestyle changes.
- Bare-metal stents. These stents can work well, but have a higher rate of restenosis than do drug-eluting stents. If you'll need some type of surgery that's not related to your heart (for example, a stomach or hernia operation) soon after your stent placement, or if you have a bleeding disorder, you may do better with a bare-metal stent.
- Drug-eluting stents. Drug-eluting stents are safe and effective in most circumstances. The key to making this treatment option effective is that you must be willing to take your medications as they're prescribed. Medications can make it less likely that blood clots in your heart will dislodge and cause a heart attack. These stents work well and have a lower rate of restenosis than do bare-metal stents.
- Coronary bypass surgery. Bypass surgery is used to divert blood around blocked arteries in the heart. This surgery uses a healthy blood vessel taken from your leg, arm, or chest and connects it to the other arteries in your heart so that blood is bypassed around the diseased or blocked area. While bypass surgery works well, it's also more invasive than using stents, which means a longer recovery time. In addition, the risk of complications for bypass surgery can be higher than with stents.
It's very important that you take anti-clotting medications exactly as directed by your doctor. Here's what to do if you have a stent of any kind:
- Take aspirin. If you have a stent, you'll have to take aspirin daily and indefinitely to reduce the risk of clotting. Follow your doctor's instructions on how much and what type of aspirin to take.
- Take anti-clotting medication. People with stents are given prescription anti-clotting medications, such as clopidogrel (Plavix). The American Heart Association and Food and Drug Administration recommend that people who have had drug-eluting stents inserted should continue to take medications, such as clopidogrel, to reduce the risk of stent clotting for at least one year after the stent is inserted. In some high-risk situations, your cardiologist may recommend taking clopidogrel indefinitely.
- Listen to your cardiologist. Always talk with your cardiologist about how long you should take anti-clotting and other medications because the answer will vary depending on the nature of your blockage and your risk of bleeding. The most important thing to remember is to take all your medications exactly as your doctor prescribes.
- Talk to your other health care providers. It's important to let your primary care doctor and any other specialists you see know what medications you take and that you have a stent. Anti-clotting medications and aspirin can affect surgeries and other medical procedures, and may interact with other medications.
If you're considering surgery not related to your heart (noncardiac surgery) in the year after receiving your stent, there are some additional things to keep in mind:
- If possible, you should postpone your noncardiac surgery for one year after receiving a stent.
- If the surgery can't be postponed, discuss with your doctor medications you should be taking at the same time, such as aspirin or clopidogrel. Your medication dosages might need to be changed.
- If you're likely to need surgery in the year after you get a stent, a bare-metal stent may be a better treatment for you. You may also want to consider a bare-metal stent if you're at an increased risk of bleeding or don't think you'll be able to take anti-clotting medications as prescribed by your doctor. Talk with your doctor about your situation.
Jul. 14, 2011
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