After drug-coated stents are placed in heart arteries, use of 2 drugs for 1 year or less reduces deaths compared with longer use

Palmerini T, Benedetto U, Bacchi-Reggiani L, et al. Mortality in patients treated with extended duration dual antiplatelet therapy after drug-eluting stent implantation: a pairwise and Bayesian network meta-analysis of randomised trials. Lancet. 2015; 385:2371-82

Review question

After people with coronary heart disease have drug-coated stents placed in the heart arteries, should 2 antiplatelet drugs be used together for a longer or shorter time?

Background

In people with coronary heart disease, arteries in the heart become narrowed or blocked. Putting stents in the arteries can open them up, and coating the stents with drugs (drug-eluting stents) can help keep blockages from coming back. However, stents can cause blood clots, which can cause strokes and heart attacks. Antiplatelet drugs help prevent blood clots, but can also cause bleeding, in people who have stents in the heart. 2 antiplatelet drugs are often used together (dual antiplatelet therapy) to prevent blood clots. It hasn’t been clear whether dual antiplatelet therapy should be used for a shorter or longer time after people get stents.

How the review was done

The researchers did a systematic review, searching for studies published up to November 2014.

They found 10 randomized controlled trials, with 31,666 people (average age 62 to 68 years). In these trials, 63% to 81% of the people were men.

The key features of the trials were:

• people had drug-eluting stents placed in heart arteries;
• dual antiplatelet therapy was taken for a shorter time (3 months, 6 months, or 12 months) or a longer time (12 months or more) after stents were placed; and
• dual antiplatelet therapy most often included aspirin combined with clopidogrel.

What the researchers found

Compared with dual antiplatelet therapy taken for 1 year or more, shorter use reduced deaths and bleeding but increased heart attacks and blood clots from the stent.

Conclusion

After drug-coated stents are placed in heart arteries, use of dual antiplatelet therapy for about 1 year or less reduces deaths and bleeding but increases heart attacks and blood clots in stents compared with longer use.

Shorter vs longer use of dual antiplatelet therapy after drug-coated stents were placed in heart arteries

*Although the rates for the 2 groups look a little different, the differences were not statistically significant. This means that the differences could simply be due to chance rather than due to the different treatments.