Do patients with drug-eluting (coronary artery) stents require anticoagulation therapy?

From the Guidelines

Patients with drug-eluting cardiac stents typically require dual antiplatelet therapy (DAPT), not full anticoagulation. The standard recommendation is aspirin 81mg daily indefinitely plus a P2Y12 inhibitor such as clopidogrel 75mg daily, ticagrelor 90mg twice daily, or prasugrel 10mg daily for at least 6-12 months after stent placement, as supported by the 2016 ACC/AHA guideline focused update on duration of dual antiplatelet therapy in patients with coronary artery disease 1.

Key Considerations

• For most patients with newer-generation drug-eluting stents, 6 months of DAPT is sufficient, though high-risk patients (those with acute coronary syndrome, complex procedures, or multiple risk factors) may benefit from 12 months or longer.
• After completing the DAPT period, patients should continue aspirin indefinitely.
• This regimen prevents stent thrombosis by inhibiting platelet aggregation while the stent endothelializes.
• The drug coating on these stents inhibits excessive tissue growth but delays complete healing, necessitating longer antiplatelet therapy compared to bare metal stents.

Special Considerations

• If a patient also has an indication for anticoagulation (such as atrial fibrillation), careful consideration of bleeding risk is needed, and often a shortened DAPT course plus anticoagulation is used under cardiologist guidance.
• The 2016 ACC/AHA guideline update provides a framework for evaluating the duration of DAPT, including the use of newer-generation drug-eluting stents and the consideration of patient-specific factors such as bleeding risk and ischemic risk 1.

Recommendations

• Patients with drug-eluting cardiac stents should receive DAPT for at least 6-12 months after stent placement, with the duration of therapy individualized based on patient-specific factors.
• Aspirin should be continued indefinitely after completion of the DAPT period.
• Patients with indications for anticoagulation should be managed under the guidance of a cardiologist, with careful consideration of bleeding risk and the potential need for a shortened DAPT course plus anticoagulation.

From the Research

Anticoagulation in Patients with Drug-Eluting Cardiac Stents

• The need for anticoagulation in patients with drug-eluting cardiac stents is a complex issue, with various studies providing insights into the optimal duration of dual antiplatelet therapy (DAPT) and its associated risks and benefits 2, 3, 4, 5, 6.
• DAPT is commonly used to reduce thrombotic events in patients undergoing percutaneous coronary intervention (PCI), but it increases the risk of bleeding compared to aspirin monotherapy 2.
• Studies have investigated the non-inferiority of P2Y12 inhibitor monotherapy compared to DAPT after mandatory 3-month DAPT in patients undergoing PCI with current-generation drug-eluting stents (DES) 2.
• The optimal duration of DAPT after DES implantation is not certain, with guidelines recommending 12 months of DAPT based on observational trials, while randomized controlled trials suggest a non-inferiority of shorter duration of DAPT and other trials showing a benefit from extended duration of DAPT after 12 months of DES implantation 5.

Risks and Benefits of DAPT

• Longer DAPT results in a significant reduction in stent thrombosis and myocardial infarction, but increases major bleeding compared to shorter DAPT 5.
• Extended-term DAPT is associated with a reduced risk of myocardial infarction, but increases the risk of major bleeding compared to 12-month DAPT 6.
• Short-term DAPT followed by P2Y12 inhibitor monotherapy reduces major bleeding after PCI with drug-eluting stents, while extended-term DAPT reduces myocardial infarction at the expense of more bleeding events 6.

Clinical Implications

• The decision to use anticoagulation in patients with drug-eluting cardiac stents should be individualized, taking into account the patient's risk of bleeding and ischemic events 4.
• In patients at high bleeding risk, short-term DAPT may be a suitable option, while in patients with acute coronary syndrome, extended-term DAPT may be beneficial in reducing myocardial infarction 3, 6.