Division News

Drug-coated Stents: Frequently Asked Questions

Duke cardiologists Robert M. Califf, M.D., vice chancellor for clinical research, and David F. Kong, M.D., associate professor of medicine, are two of the co-authors of the stent study published online by the Journal of the American Medical Association on December 5, 2006. They've answered the following questions about stents and about their new research findings.

1. What is a stent and what are the different kinds of stents?

Stents are thin metal mesh tubes that prop open the arteries that supply blood to the heart. Physicians often implant stents after unblocking a coronary artery with a tiny balloon in a procedure known as angioplasty (angio=blood vessel, plasty=fix). Stents reduce the risk of recurring blockages in coronary arteries after the artery has been opened.

The first stents, known as bare metal stents, were not coated with medicine. Unfortunately, the artery sometimes forms a scar inside the stent, and this scar can block the stent. As a result, patients sometimes need to have another angioplasty.

Newer stents have been coated with drugs designed to prevent the build-up of scar tissue inside the stent. These devices are called drug eluting stents, and nine out of 10 stents placed in the US today are this kind. Drug eluting stents reduce the need for a repeat procedure from 1 in 5 (for bare metal stents) to 1 in 12 (for drug eluting stents).

2. Why are doctors concerned about drug eluting stents?

Recent reports have shown that drug eluting or drug coated stents may be associated with the development of blood clots that could lead to heart attacks or death. The risk of a blood clot inside a stent is 8 in 1000. For comparison, your risk of dying in an automobile accident is 6 in 1000.

3. Is there a way to stop such clots from developing?

To stop clots from forming within a drug coated stent, doctors have their patients take aspirin, if they are able to, along with a drug known as Plavix for three to six months, as recommended by the FDA.

The most common side effects of Plavix are stomach pain, gastrointestinal discomfort, headaches, dizziness, and bleeding. Patients taking Plavix may be asked by their doctors to stop taking the drug if they are going to have an invasive procedure or surgery that could lead to bleeding.

4. Are there any problems associated with stopping Plavix?

There are some very recent reports that suggest that patients who stop taking Plavix three to six months after placement of a drug coated stent have higher rates of heart attacks and death than those who continue to take it. Because of these recent findings, we recommend that unless there is a reason not to take Plavix it should be continued until better information is available.

No clinical trials have been done yet to understand the effects of long-term Plavix use, so these recommendations are temporary until further long-term studies are done to clarify these issues. It is important to recognize that these trials could take 5 years to complete, so in the meantime you should have a discussion with your doctor to make a good decision based on the information we currently have available.

5. What should I do if I have a drug coated stent and I'm no longer taking Plavix?

We recommend that you speak with your doctors, particularly your cardiologist, for individual advice. Every person has a different set of risk factors for blood clots or bleeding. However, if you stopped Plavix within the past year, we think you should resume taking it daily with aspirin (81 mg – the dose of a baby aspirin) unless there is a medical reason not to do so. If you have been off Plavix for more than a year, we are less certain about what you should do, and we recommend that you have a discussion with your doctor to make the best decision considering all aspects of your individual situation. Only new clinical trials will determine how long patients should take Plavix, and these studies will take several years to complete.

6. What should I do if I have a drug eluting stent and I am still taking Plavix?

Again, we recommend that you speak with your doctors, particularly your cardiologist, for individual advice. But the data from our study strongly advise that unless there is a medical reason to the contrary you should continue to take daily Plavix and aspirin, if possible, indefinitely, until further information is available.

The question of how long patients with drug coated stents need to take Plavix can only be answered by rigorously conducted clinical trials that we believe should be initiated and completed as soon as possible.

7. How can I tell if my cardiologist put in a bare metal stent or a drug eluting stent?

After your stent procedure, you may have received a booklet or a wallet card that lists the model, size, and serial number of your stent. The drug eluting stents in the United States are known as either the Cypher stent, produced by Cordis, or the Taxus stent, produced by Boston Scientific. That information will be in the booklet or wallet card.

Another option, of course, is to contact your physician.

8. Can I have the stent taken out?

No, removal of stents is not an option. Once a stent is implanted in an artery, the tissue in the artery grows and covers the stent. Therefore, it cannot be removed.

9. What are the medical conditions that would make treatment with Plavix dangerous for people with drug coated stents?

The primary condition would be active bleeding or a history of major bleeding. The most common side effect experienced by patients receiving Plavix is bleeding. Patients with active bleeding (except normal menstruation) should not be taking Plavix as it could result in excessive bleeding.

In rare instances, individuals have reported allergic reactions to Plavix, such as rashes or hives. In extremely rare cases (approximately 4 patients per 1,000,000), patients have experienced a severe allergic reaction called thrombotic thrombocytopenic purpura (TTP). If you are unsure whether you have had an allergy or other side effect due to treatment with Plavix, consult your doctor before restarting treatment.

10. If I can't take Plavix, am I at high risk of dying soon?

The good news is that the risk of suddenly developing a blood clot in a drug coated stent is pretty low (on average, less than 2 percent of patients per year). However, the risk is even lower in patients who take Plavix. Again, your physician can make individual recommendations to reduce your risk of developing a clot, including the continued use of an aspirin every day.

11. What should I do if I'm told I need a drug coated stent?

You and your doctor should consider all options, including bare metal stents and bypass surgery, especially if you cannot take Plavix for a long time. If taking Plavix will not be a problem, a drug coated stent might be the best option for you. Your decision should be based on a serious conversation between you and your doctor.

In an emergency there may not be time for such a discussion, but you should be assured that this issue is a top priority among doctors who implant stents.

12. What if I can't afford to take Plavix for a long time?

There is a program from Sanofi Aventis and Bristol-Myers Squibb, the companies that manufacture and sell Plavix, that helps patients with financial problems get the drug. We can help you with the paperwork as it must be cleared through your doctors.

13. Is there a substitute for Plavix?

There is only one drug on the market that is similar to Plavix. It is an older drug known as ticlopidine, or Ticlid, which has a higher incidence of side effects than Plavix and similar risks of bleeding. In rare circumstances ticlopidine may be an acceptable substitute for Plavix.

Remember that daily aspirin in small amounts, unless you cannot take it, is important in reducing the risk of developing a blood clot.

14. Is there a number I can call to talk to a person about these issues?

At Duke: Duke Consultation & Referral Center 1-888-ASK DUKE.

http://www.dukeheartcenter.org

At Sanofi-Aventis about Plavix:

Sanofi-Aventis
Customer Information Center
1-800-207-8049

Sanofi-Aventis
Medical Information Services
1-800-633-1610

http://www.plavix.com

At Bristol-Myers Squibb about Plavix:

Bristol-Myers Squibb Customer relations: 1-800-332 2056

http://www.plavix.com

At Cordis/Johnson and Johnson about drug eluting stents:
CYPHER® Stent Medical Information Center
Phone: (800) 781-0282
Fax: (908) 927-5786
Hours of Operation Monday – Friday 8:30AM - 6:00PM (Eastern Standard Time). After-hour service is available for urgent information requests. Please contact 1-800-781-0282 and follow prompts to reach the on-call CYPHER® Stent Medical Information Specialist.

http://www.cypherusa.com

At Boston Scientific about drug eluting stents:
Call Customer Service at 1-888-272-1001 for product related questions.
http://www.taxus-stent.com