Kim A. Eagle, MD, MACCImportant Updates to the Recommendations on Dual Antiplatelet Therapy

Kim A. Eagle, MD, MACC
Editor-in-Chief, ACC.org

The release of the ACC/AHA Focused Update on the Duration of Dual Antiplatelet Therapy (DAPT) represents an important event, in that its findings impact six already released ACC/AHA Clinical Practice Guidelines:

  1. ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention
  2. ACCF/AHA Guideline for Coronary Artery Bypass Graft (CABG) Surgery
  3. ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease (SIHD)
  4. ACC/AHA Guideline for the Management of ST-Elevation Myocardial Infarction (STEMI)
  5. ACC/AHA Guideline for Non–ST-Elevation Acute Coronary Syndromes (NSTEMI)
  6. ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery

The scope of the update is limited to the duration of dual antiplatelet therapy, as well as the effectiveness of DAPT compared to aspirin alone in patients with coronary artery disease.

This update will have an impact on many stakeholders, including the practicing cardiologist, the interventionalist, the surgeon, and the internist, and of course, our patients. Seldom have we seen a single area of cardiovascular research impact such a broad array of our ACC/AHA Clinical Practice Guidelines.

To that end, we have gathered ACC experts to address a number of questions about the update, listed below. Click on the link to find an expanded “answer” to all the questions you have about the update. Please also find related resources along the right side of this page and vote on whether your will change your behavior based on the recommendations. Leave your comment, below, as we look forward to hearing from you.

FAQ’s

Click the questions below to expand or collapse its answer.

  • In a patient with a recent ACS, receiving a second generation DES, what are the key factors that might cause one to extend DAPT beyond one year?
  • Lee Fleisher, MD, FACCNanette Kass Wenger, MD, MACC responds: The major academic focus for my decision to recommend extension of dual antiplatelet therapy (DAPT) beyond one year following implantation of a second generation drug eluting stent (DES) derives from the excellent DAPT trial data. The authors report, in addition to the reduced rates of stent thrombosis (1.4% with placebo and 0.4% with continued dual antiplatelet therapy, p<0.001), a reduction in the major adverse cardiovascular and cerebrovascular events (4.3% compared with 5.9% in the control population who received aspirin alone, p<0.001), and a lower rate of myocardial infarction (2.1% vs 4.1%, p<0.001). This suggests benefit of such therapy not only for the stent per se, but in the native circulation. Not unanticipated was the increased rate of moderate or severe bleeding with continued thienopyridine treatment (2.5% vs 1.6%, p=0.001). Read more >>>

  • A patient recently received a DES for unstable angina, then needed an emergent CABG now. How long after the CABG should she continue DAPT?
  • ooooooFaisal Bakaeen, MD responds: This is a difficult question to answer. There are few data to guide the surgeon in such a scenario, with most data derived primarily from subgroup analyses of trials designed to evaluate DAPT in ACS patients who then require CABG surgery. However, findings from a recent meta-analysis suggest that higher intensity (prasugrel or ticagrelor) but not lower intensity (clopidogrel) DAPT is associated with lower mortality in ACS patients treated with CABG surgery1. The addition of a DES adds additional complexity not only with regard to how long the patient should be on DAPT after CABG surgery, but also whether DAPT is truly indicated in the first place and whether it conveys a proven benefit. Read more >>>

  • For CAD, what is the recommended dose of aspirin and why?
  • Patrick T. O’Gara, MD, MACCPatrick T. O’Gara, MD, MACC responds:

    Recommended Aspirin Doses in Patients with Coronary Artery Disease

    Aspirin is indicated for prevention and/or treatment of a wide variety of cardiovascular conditions, including primary and secondary prevention, percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG) surgery, peripheral arterial disease (PAD), extra-cranial arterial disease, mechanical heart valve replacement and pericarditis. Although there is general consensus that lower doses of aspirin are usually as effective as, and safer than, higher doses for most indications, there is much variability in prescribing patterns in part related to the lack of a robust evidence base for certain disease states. An example of an effort to close this knowledge gap is the anticipated launch of the Patient Centered Outcomes Research Institute’s (PCORI) Aspirin Dosing: A Patient-Centric Trial Assessing Benefits and Long-Term Effectiveness (ADAPTABLE) Trial, a study that will compare aspirin doses of 81 mg versus 325 mg for secondary prevention among 20,000 patients with stable cardiovascular disease (CVD) (NCT02697916). Read more >>>

  • In considering triple therapy for patients with atrial fibrillation and either ACS and/or recent coronary stenting, please answer the following questions:
    • Is there a preferred P2Y12 inhibitor and at what dose?
    • Is a DDAC or warfarin preferred as part of the combination therapy?
    • When should a proton-pump inhibitor be prescribed?
    • Should the target INR be adjusted?
    • What aspirin dose is recommended?
    • How long should one continue triple therapy?

    Glenn N. Levine, MD, FACC, FAHAGlenn N. Levine, MD, FACC, FAHA responds: Approximately 5% of patients undergoing PCI have atrial fibrillation and require long-term oral anticoagulant therapy.1 Clinicians are thus frequently confronted with choosing the optimal treatment strategy in patients with both atrial fibrillation and recent coronary stent implantation. Choosing the best treatment strategy is analogous to navigating the Strait of Messina between Scylla and Charybdis. If one navigates the patient towards long-term triple therapy (aspirin plus P2Y12 inhibitor plus oral anticoagulant) the bleeding risk may be excessive; conversely, navigating him or her towards less intense therapy raises the risk the ischemic complications (primarily stroke or stent thrombosis). Read more >>>

  • For stable ischemic heart disease patients receiving a coronary stent, what is the minimum duration of DAPT after:
    • Bare Metal Stent?
    • Drug Eluting Stent?

    Richard A. Lange, MD, MBA, FACCRichard A. Lange, MD, MBA, FACC responds: The risk of stent thrombosis in patients treated with a bare metal stent (BMS) is greatest in the first days to weeks after implantation. Cessation of dual antiplatelet therapy (DAPT) during this period, particularly in cases of patients undergoing surgery, is associated with an unacceptable rate of stent thrombosis, which is often catastrophic. Thus, a minimum duration of DAPT for 1 month is generally recommended in stable ischemic heart disease (SIHD) patients treated with a BMS. Read more >>>

  • After a STEMI treated with thrombolytic therapy, what is the minimum duration of DAPT as well as the recommended duration of DAPT?
  • Debabrata Mukherjee, MD, FACCDebabrata Mukherjee, MD, FACC responds: Fibrinolytic therapy in patients with ST elevation MI (STEMI) has proven benefit. Furthermore, the beneficial effects of aspirin and clopidogrel as adjunctive therapy with fibrinolysis are well established and these agents should be given before or with the fibrinolytic.1 Aspirin should be administered immediately if not already taken by the patient at home or administered by EMS before arrival. Based on available data, the optimal range of aspirin dose in patients treated with DAPT that provides maximal protection from ischemic events and minimizes bleeding risk appears to be 75 mg to 100 mg.2 Since aspirin dose available in the United States is 81 mg, this maintenance dose is recommended in patients with coronary artery disease treated with DAPT. Read more >>>

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