What is the role of Dual Antiplatelet Therapy (DAPT) in Percutaneous Coronary Intervention (PCI)?

From the Guidelines

Dual Antiplatelet Therapy (DAPT) is essential following Percutaneous Coronary Intervention (PCI) to prevent stent thrombosis and major adverse cardiovascular events, with the standard regimen consisting of aspirin combined with a P2Y12 inhibitor, and duration varying based on clinical factors, typically 6-12 months for drug-eluting stents and at least 1 month for bare-metal stents. The most recent and highest quality study, 1, published in 2022, provides an updated guideline for the use of DAPT in patients after PCI, recommending at least 1 month of aspirin plus a P2Y12 inhibitor for patients with stable ischemic heart disease (SIHD) or acute coronary syndrome (ACS) who receive a drug-eluting stent (DES).

For patients with SIHD who receive a DES, the guideline suggests that 6 months of DAPT may be sufficient, while for those with ACS, at least 12 months of DAPT is recommended 1. The guideline also notes that for patients at high risk of bleeding or with overt bleeding on DAPT, a shorter duration of 3 months may be reasonable, while for those without high bleeding risk, extended DAPT beyond 12 months may be considered.

The mechanism of DAPT involves inhibiting platelet activation through complementary pathways, with aspirin blocking thromboxane A2 production via COX-1 inhibition, and P2Y12 inhibitors preventing ADP-mediated platelet aggregation, providing more comprehensive platelet inhibition than either agent alone, and effectively preventing clot formation within the stent and reducing recurrent cardiovascular events while the vessel endothelializes following PCI.

Key considerations in determining the duration of DAPT include the patient's bleeding risk, as assessed by tools such as the PRECISE-DAPT score, which integrates factors such as age, creatinine clearance, and prior spontaneous bleeding to guide treatment duration, as noted in the 2018 European Heart Journal study 1. However, the most recent guideline from 2022 1 takes precedence in guiding clinical practice.

In terms of specific P2Y12 inhibitors, options include clopidogrel, ticagrelor, and prasugrel, with the choice depending on individual patient factors and clinical presentation, as outlined in the 2016 Circulation study 1. Ultimately, the decision on DAPT duration and regimen should be individualized based on a careful assessment of the patient's ischemic and bleeding risks, with consideration of the latest clinical guidelines and evidence.

From the FDA Drug Label

Prasugrel tablets are indicated to reduce the rate of thrombotic CV events (including stent thrombosis) in patients with acute coronary syndrome (ACS) who are to be managed with percutaneous coronary intervention (PCI) Patients taking prasugrel tablets should also take aspirin (75 mg to 325 mg) daily

The role of Dual Antiplatelet Therapy (DAPT) in Percutaneous Coronary Intervention (PCI) is to reduce the rate of thrombotic cardiovascular events, including stent thrombosis, in patients with acute coronary syndrome (ACS).

• DAPT with prasugrel and aspirin is indicated for patients with unstable angina or non-ST-elevation myocardial infarction (NSTEMI), and for patients with ST-elevation myocardial infarction (STEMI) when managed with primary or delayed PCI 2.
• The standard dosing regimen for prasugrel is a single 60 mg oral loading dose, followed by 10 mg orally once daily, in combination with aspirin (75 mg to 325 mg) daily 2 2.

From the Research

Role of DAPT in PCI

• Dual Antiplatelet Therapy (DAPT) is essential in all patients undergoing Percutaneous Coronary Intervention (PCI) to prevent thrombotic complications 3, 4.
• DAPT typically consists of aspirin and a P2Y12 inhibitor, which is the cornerstone of treatment in patients undergoing PCI 3, 4, 5.
• The use of DAPT has been shown to reduce the risk of stent thrombosis and other thrombotic events in patients undergoing PCI 4, 6.

Benefits and Risks of DAPT

• DAPT has been shown to reduce the risk of ischemic events in patients undergoing PCI, but it also increases the risk of bleeding complications 3, 6.
• The risk of bleeding associated with DAPT can be significant, particularly in patients with concomitant atrial fibrillation (AF) who require oral anticoagulant (OAC) therapy 3.
• Strategies to minimize bleeding risk while maintaining the benefits of DAPT are crucial, including the use of dual antithrombotic therapy (DAT) instead of triple antithrombotic therapy (TAT) in some patients 3, 6.

Personalized DAPT Approaches

• Guided DAPT approaches, which involve modifying the type or dose of antiplatelet drugs based on platelet function or genetic testing, may be beneficial in certain patients 7, 5.
• These approaches aim to intensify antiplatelet potency in patients at high risk of thrombotic events and decrease antiplatelet potency in patients at high risk of bleeding 7.
• However, the routine use of platelet function testing (PFT) or genetic testing is not recommended, and selective use of these assays should be considered on a case-by-case basis 5.