Stent Advisory Warns of Dire Cost of Early Halt to Antiplatelets

ROYAL OAK, Mich. Jan 16 -- Citing the risk of "catastrophic complications" if dual-antiplatelet use is halted in the 12 months after implanting a drug-eluting stent, five professional societies signed off on a stern advisory aimed at reducing thromboses.

Whereas previous statements described 12 months of Plavix (clopidogrel) plus aspirin as a preferred treatment for patients who had no known excess bleeding risk, the new statement was unequivocal. Patients who get a drug-eluting stent should have 12 months of Plavix and aspirin.

In patients "not expected to comply with 12 months of thienopyridine therapy, for whatever reasons, a bare metal stent should be strongly considered," the advisory stated.

The advisory statement, which was simultaneously published in Circulation, Journal of the American Heart Association, Journal of the American College of Cardiology, and Cathertization and Cardiovascular Interventions: Journal of the Society for Cardiovascular Angiography and Interventions, was endorsed by the AHA, ACC, SCAI, the American College of Surgeons, and the American Dental Association.

The American College of Physicians was represented on the writing group, but the ACP did not officially endorse the statement.

Raymond J. Gibbons, M.D., of the Mayo Clinic in Rochester, Minn., who is president of the AHA, said the dentists and surgeons were invited to join the discussion because both often play a pivotal role in Plavix-aspirin compliance.

Concerned about the potential for bleeding, dentists ask patients to stop taking the drugs before dental procedures, while surgeons advise patients to stop taking the drugs before surgery.

Patients should be told to get in touch with their cardiologist before stopping any antiplatelet therapy for any reason, "even if instructed to do so by another healthcare provider," said the advisory.

It also recommended that all "healthcare providers who perform invasive or surgical procedures should be made aware of the potentially catastrophic risk of prematurely stopping thienopyridine therapy, and should contact the patient's cardiologist to discuss optimal patient management."

Patients who undergo procedures that mandate stopping Plavix should be continued on aspirin, and Plavix should be restarted as soon as possible after the procedure, according to the advisory statement.

The statement cited a large observational cohort study in which stent thrombosis occurred in 29% of drug-eluting stent patients who stopped the Plavix (clopidogrel) plus aspirin regimen prematurely.

In that study by Iakovou et al, premature cessation of dual anti-platelet therapy was associated with a "hazard ratio of 161 (95% confidence interval, 26 to 998) for the occurrence of subacute stent thrombosis and a hazard ratio of 57 (95% CI 15 to 220) for the occurrence of late stent thrombosis," said Cindy Grimes, M.D., of William Beaumont Hospital here, who chaired the advisory committee that wrote the statement.

Dr. Gibbons said in an interview that he was particularly concerned because the increased event risk extends to "low risk patients, the patients who meet the study protocols."

Last month an FDA advisory panel that reviewed the safety of drug-eluting stents for two days concluded that the stents were safe when used according to label indications, meaning for patients with uncomplicated, single-vessel disease.

Although the FDA panel said Plavix and aspirin should be continued for 12 months when the stents are used off label, which accounts for about 60% of all drug-eluting stents implanted in the United States, they said it wasn't necessary when the stents are used according to label indications.

The label indications recommend three months of Plavix plus aspirin for patients treated with Cypher (sirolimus-eluting) stents and six months for Taxus (paclitaxel-eluting) stents.

Other recommendations from the five-society advisory:

• Before implanting a drug-eluting stent, physicians should discuss the need for antiplatelet therapy with the patient.
• In patients who are likely to require surgery within 12 months of receiving a stent, a bare-metal stent or balloon angioplasty with a provisional stent should be considered rather than routinely using a drug-eluting stent.
• Healthcare professionals must make a greater effort to educate patients before hospital discharge about the reasons for prescribing Plavix and for taking dual antiplatelet therapy, as well as the risks to stopping it early.
• Elective procedures that carry a risk of bleeding should be delayed until a month after the patient has completed Plavix plus aspirin therapy, ideally13 months after stent implantation.
• The healthcare industry, insurers, Congress, and the pharmaceutical industry should insure that issues such as drug cost do not cause patients to prematurely discontinue Plavix, risking catastrophic complications.