ACC/AHA Publish 2016 Focused Update of Guidelines for DAPT

March 31, 2016—The American College of Cardiology (ACC) and the American Heart Association (AHA) jointly released updated guidelines for dual-antiplatelet therapy (DAPT) in patients with coronary artery disease. DAPT is a combination of aspirin with a P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor) to reduce the risks of future heart attack and coronary stent thrombosis. The document updates recommendations on DAPT in six previously published guidelines from 2011 to 2014.

The document is available online ahead of print in the Journal of the American College of Cardiology and Circulation.

According to ACC/AHA, these new guideline recommendations are based on the findings of recent studies on the length of time patients with coronary artery disease, specifically those with myocardial infarction and those undergoing coronary stent implantation, should be treated with DAPT. The new recommendations are also based on current use of coronary stents that have a lower risk of clotting off than some older stents.

The societies noted that studies examining shorter duration (3–6 months) of DAPT compared with a standard 12 months of therapy in select, generally lower-risk patients did not find any increased risk of stent thrombosis and, in some cases, found less bleeding. Other studies of prolonged or extended DAPT for an additional 18 or 36 months found a decrease in the risk of heart attack and stent thrombosis at the expense of an increase in bleeding risk.

In the announcement, Glenn N. Levine, MD, the Chair of the ACC/AHA writing committee for the document, commented, “Treatment with more intensive antiplatelet therapy and treatment for a longer duration of time with antiplatelet medicines in general involves a fundamental tradeoff between a decreased risk of future heart attack and an increased risk of bleeding complications.” Dr. Levine is Professor of Medicine at Baylor College of Medicine and Director of the Cardiac Care Unit at the Michael E. DeBakey VA Medical Center in Houston, Texas.

As summarized in the ACC/AHA announcement, duration-of-DAPT recommendations in the document consist of a class I recommendation of “should be given” for a minimum period of time (usually 6–12 months) and a class IIb recommendation of “may be considered” for continuation beyond that time. A shorter duration of DAPT is recommended for patients at lower ischemic risk but high bleeding risk, whereas a longer duration of DAPT may be reasonable for patients at higher ischemic risk but lower bleeding risk. These recommendations for the duration of DAPT apply to newer-generation stents and, in general, only to patients not treated with oral anticoagulant therapy.

A dose of 81 mg daily (range, 75–100 mg) is now recommended in patients treated with DAPT. Regardless of the duration of DAPT, aspirin therapy is almost always continued indefinitely in patients with coronary artery disease.   

The guideline focused update also addresses DAPT after coronary artery bypass grafting and issues regarding the timing of noncardiac 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 thus best individualized, reported ACC/AHA.