Optimal duration of dual antiplatelet therapy after drug-eluting stent

This paper looked at the best duration for dual antiplatelet therapy (DAPT) in patients who had a drug-eluting stent or a heart attack. Results showed that patients receiving safer, newer drug-eluting stents may have a minimum DAPT duration of 3 to 6 months. Researchers also noted that the extension of DAPT to more than 1 year reduces the risk of heart attacks, but increases the risk of major bleeding. 

Dual antiplatelet therapy refers to treatment with 2 antiplatelet drugs (drug that prevents blood cells from sticking together). Clopidogrel (Plavix), Ticagrelor (Brilinta), Prasugrel (Effient), and Aspirin are examples or antiplatelet drugs. The American Heart Association previously recommended dual antiplatelet therapy for at least 12 months after insertion of a drug-eluting stent. A drug-eluting stent is a mesh wired structure placed into a blood vessel that releases drugs and prevents narrowing of the blood vessel. As stent technology improves, there is a need to evaluate the best duration of DAPT. 

11 studies involving 33,051 patients were analyzed. There was no difference in death, major bleeding, stent clots, and heart attack when comparing DAPT for 12 months to DAPT for 3 to 6 months.

6 studies compared 18 to 48 months of DAPT with 6 to 12 months of DAPT. The results showed that a longer DAPT was not associated with any difference in death. Longer DAPT was associated with a 58% increased risk of major bleeding. However, longer DAPT reduced the risk of a heart attack by 33%, and reduced the risk of a clot in the stent by 48%. 16 of every 1,000 patients who received the longer DAPT died during each year of extended therapy. In contrast, 14 of every 1000 patients who received the shorter DAPT died during each year of extended therapy.  

Use of DAPT for more than 1 year after a heart attack reduced the risk of death, heart attack or stroke, but increased the risk of major bleeding 2.32-fold. 

The authors concluded that prolonged DAPT after a drug-eluting stent placement reduces risk of stent clot and heart attacks, but increases risk of major bleeds.