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The American College of Cardiology (ACC) and American Heart Association (AHA) have released updated guidelines for the use of dual antiplatelet therapy (DAPT) in patients with coronary artery disease.
DAPT, the combination of aspirin and a P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor), is used to reduce the risks of future heart attack and coronary stent thrombosis in this patient population.
Overall, the new guidelines, which update recommendations from 6 previous guidelines, recommend an individualized approach to DAPT.
The guidelines were published in the Journal of the American College of Cardiology.
The new recommendations are based on the current use of coronary stents that present a lower risk of thrombosis than some older stents.
The recommendations are also based on the findings of recent studies investigating the duration of DAPT in patients with coronary artery disease, specifically those with myocardial infarction and those undergoing coronary stent implantation.
Studies examining shorter duration (3 to 6 months) of DAPT compared with a standard 12 months of DAPT in select, generally lower-risk patients did not show an increased risk of stent thrombosis. And, in some cases, a shorter treatment duration was associated with less bleeding.
Other studies investigating extending DAPT for an additional 18 or 36 months (beyond a year) showed a decrease in the risk of heart attack and stent thrombosis at the expense of an increase in bleeding risk.
Overview of recommendations
In general, the recommendations regarding DAPT duration consist of a Class I recommendation of “should be given” for a minimum period of time (usually 6 to 12 months), and a Class IIb recommendation of “may be considered” for continuation beyond that time.
Shorter duration of DAPT is recommended for patients at lower ischemic risk with high bleeding risk, whereas longer duration of DAPT may be reasonable for patients at higher ischemic risk with lower bleeding risk.
These recommendations for duration of DAPT apply to newer-generation stents and, in general, only to those not treated with oral anticoagulant therapy.
An aspirin dose of 81 mg daily (range, 75-100 mg) is now recommended in patients treated with DAPT. Regardless of the duration of DAPT, aspirin is almost always continued indefinitely in patients with coronary artery disease.
The updated guidelines also address DAPT after coronary artery bypass grafting and issues regarding the timing of non-cardiac surgery in patients treated with coronary stent implantation and DAPT.
Decisions about the timing of surgery and whether to discontinue DAPT after coronary stent implantation involve weighing the particular surgical procedure and the risks of delaying the procedure, the risks of ischemia and stent thrombosis, and the risk and consequences of bleeding, and are therefore best individualized, according to the guidelines.
The new guidelines update recommendations on the duration of DAPT across 6 previously published guidelines:
- The 2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention
- The 2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery
- The 2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease
- The 2013 ACC/AHA Guideline for the Management of ST-Elevation Myocardial Infarction
- The 2014 ACC/AHA Guideline for Non-ST-Elevation Acute Coronary Syndromes
- The 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery.
