The American College of Cardiology and the American Heart Association have released a focused update on duration of dual antiplatelet therapy for patients with CAD, generally recommending that dual antiplatelet therapy duration decisions be made on an individualized basis depending on thrombotic and bleeding risks.
The recommendations update six previously released guidelines, including the 2011 ACC/AHA/Society for Cardiovascular Angiography and Interventions guideline on PCI, the 2011 ACC/AHA guideline on CABG, the 2012 ACC/AHA/SCAI/American College of Physicians/American Association for Thoracic Surgery/Preventive Cardiovascular Nurses Association/Society of Thoracic Surgeons guideline on stable ischemic heart disease, the 2013 ACC/AHA guideline on STEMI, the 2014 AHA/ACC guideline on non-ST-elevation ACS and the 2014 ACC/AHA guideline on CV issues in patients undergoing noncardiac surgery.
“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 [MI] and an increased risk of bleeding complications,” writing committee chair Glenn N. Levine, MD, FAHA, FACC, 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, said in a press release.
Glenn N. Levine
According to the committee, “shorter-duration DAPT can be considered for patients at lower ischemic risk with high bleeding risk, whereas longer-duration DAPT may be reasonable for patients at higher ischemic risk with low bleeding risk.” The committee noted that, in general, a minimum duration of DAPT, usually 6 to 12 months, received a Class I recommendation, while duration of DAPT beyond 12 months received a Class IIb recommendation.
“Decisions about DAPT are best made on an individual basis and should integrate clinical judgment, assessment of the benefit/risk ratio and patient preference. Aspirin is almost always indefinitely continued in patients with CAD, and recommendations on duration of DAPT should be taken to mean the recommended duration of P2Y12 inhibitor therapy (in addition to aspirin therapy),” according to the document.
These recommendations do not apply to patients on oral anticoagulation, who were not included in most studies of DAPT duration.
Levine and colleagues developed a master treatment algorithm for duration of P2Y12 inhibitor therapy in addition to aspirin therapy.
For patients with stable ischemic heart disease, those who have not had CABG or PCI should not have DAPT; those who had PCI with a bare-metal stent should have clopidogrel and aspirin for at least 1 month, though a longer duration may be reasonable in those not at high risk for bleeding and no significant overt bleeding on DAPT; those who had PCI with a drug-eluting stent should have clopidogrel and aspirin for at least 6 months, though a longer duration may be reasonable in those not at high risk for bleeding and no significant overt bleeding on DAPT; and it may be reasonable for those who had CABG to take clopidogrel and aspirin for 12 months, according to the document.
For patients with STEMI or NSTEACS, those treated with medical therapy should take clopidogrel or ticagrelor (Brilinta, AstraZeneca) and aspirin for at least 12 months; those with STEMI treated with lytic therapy should be treated with clopidogrel and aspirin for a minimum of 14 days and ideally at least 12 months; those treated with PCI (BMS or DES) should be treated with clopidogrel, prasugrel (Effient; Daiichi Sankyo/Eli Lilly) or ticagrelor plus aspirin for at least 12 months; and those treated with CABG should have DAPT for 12 months, according to the authors.
For patients with STEMI or NSTEACS treated with medical therapy, lytic therapy or PCI, continuing DAPT beyond 12 months may be reasonable if the patient does not have a high risk for bleeding and does not have significant overt bleeding in the first 12 months, Levine and colleagues wrote.
The document lists six risk factors associated with increased ischemic risk, which may favor longer-duration DAPT; 10 risk factors associated with increased risk for stent thrombosis, which may favor longer-duration DAPT; and nine risk factors associated with elevated risk for bleeding, which may favor shorter-duration DAPT.
In related news, Robert W. Yeh, MD, MSc, MBA, from the Smith Center for Outcomes Research in Cardiology, Beth Israel Deaconess Medical Center, Boston, and colleagues published in JAMA the validation of a DAPT Score to predict benefit or harm from DAPT beyond 1 year after PCI. The findings were initially presented at the AHA Scientific Sessions in November 2015.
Robert W. Yeh
To calculate the score, a patient receives –2 points for age 75 years or older, –1 point for age 65 to 74 years, 1 point for current smoking, 1 point for diabetes, 1 point for MI at presentation, 1 point for prior MI or PCI, 1 point for stent diameter < 3 mm, 1 point for having a paclitaxel-eluting stent, 2 points for congestive HF or left ventricular ejection fraction < 30% and 2 points for a saphenous vein graft PCI. A score of 2 or more confers a favorable benefit/risk ratio for prolonged DAPT after PCI, while a score of less than 2 confers an unfavorable benefit/risk ratio.
In their update of the guidelines, Levine and colleagues wrote that the DAPT Score “may be useful for decisions about whether to continue (prolong or extend) DAPT in patients treated with coronary stent implantation.”
The update was developed in conjunction with AATS, SCAI, STS, the American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists, and endorsed by PCNA and the Society for Vascular Surgery. – by Erik Swain
Levine GN, et al. Circulation. 2016; doi:10.1161/CIR.0000000000000404.
Levine GN, et al. J Am Coll Cardiol. 2016;doi:10.1016/j.jacc.2016.03.513.
Yeh RW, et al. JAMA. 2016;doi:10.1001/jama.2016.3775.
Disclosure: Levine reports no relevant financial disclosures. Please see the full document for a list of the other authors’ and reviewers’ financial disclosures. Yeh reports receiving personal fees from Abbott Vascular, Boston Scientific and Merck, a research salary from Harvard Clinical Research Institute and a pending patent for development and use of the DAPT Score. Please see the full study for a list of the other researchers’ relevant financial disclosures.