How long should antiplatelet therapy last following stent implantation?

Short-term dual antiplatelet therapy was as effective as long-term therapy for patients who underwent percutaneous coronary intervention (PCI) with a second-generation drug-eluting stent, according to an online study published in JAMA.

After undergoing PCI with zotarolimus-eluting stents, more than 3,000 patients received either aspirin (100 to 200 mg) and clopidogrel (75 mg) daily for three months or 12 months during the OPTIMIZE trial. The current recommendation following stent implantation is 12 months treatment, according to the Brazilian researchers.

Adherence to the drug regimen was almost 100% in the short-term and long-term groups at 90 days follow-up. At the 1-year follow-up, the short-term group had an adherence rate of 98.9% for aspirin and 6.2% for clopidogrel, and the long-term group had an adherence rate of 98.8% for the aspirin and 97.9% for the clopidogrel.

The primary outcome was a composite death from any cause, myocardial infarction, stroke, or major bleeding. Secondary outcomes were stent thrombosis, target-lesion and target-vessel revascularization, major cardiac events, and any bleeding.

At 1 year, 93 patients in the short-term group and 90 in the long-term group reached the primary end points (6.0% vs 5.8%, with a risk different of 0.17, demonstrating noninferiority for the short-term regimen. Stent thrombosis occurred up to 90 days in 9 patients in the short-term group and 11 in the long-term group. From 91 days to almost 1 year, 4 events occurred in the short-term group and 1 in the long-term group.

“This [noninferiority] result was similar in several key subgroups, including patients with diabetes, history of low-risk ACS, multivessel disease, or bifurcation lesions,” the authors wrote.

“It is not possible to determine whether all drug-eluting stents could benefit from short-term regimens of dual antiplatelet therapy duration based on the previous trials reported. To our knowledge, our study is the only trial to date of dual antiplatelet therapy using a single-generation drug-eluting state and in which 3 months of dual antiplatelet therapy demonstated noninferiority against 12 months of therapy with respect to hard end points associated with duration of therapy,” they noted.