Dual Antiplatelet Therapy

Antiplatelet agents have been utilized to enhance outcomes in patients with acute coronary syndrome for decades and are increasingly valued for their antithrombotic as well as anti-inflammatory characteristics. Dual antiplatelet therapy (DAPT) is a combination of aspirin and a P2Y12 inhibitor. Different modes of action are employed by these drugs. Aspirin is an anti-inflammatory medication that also has antioxidant characteristics, while P2Y12 inhibitors act by inhibiting thrombocytes activation/aggregation. There are two types of P2Y12 inhibitors: thienopyridines and nucleoside/nucleotide compounds. Nucleoside/nucleotide derivatives are reversible direct-acting P2Y12 receptor antagonists that do not need hepatic metabolism, whereas thienopyridines are competitive and irreversible P2Y12 inhibitors. In patients with acute coronary syndrome or undergoing percutaneous coronary intervention for stable coronary artery disease, dual antiplatelet therapy, which contains aspirin and a P2Y12 receptor inhibitor, has consistently been shown to reduce recurrent major adverse cardiovascular events compared to aspirin monotherapy, but at the cost of an increased risk of major bleeding. This chapter is meant to elaborate on dual antiplatelet therapy highlighting the current guidelines and recent evidences on the indications, dosing, and duration of treatment using dual antiplatelet therapy.