Advances in Antiplatelet and Anticoagulant Therapies for NSTE-ACS

The treatment of patients requiring anticoagulation who develop acute coronary syndrome (ACS) and/or require percutaneous coronary intervention (PCI) must balance the reduction in major adverse cardiovascular events, stroke, and major bleeding. The development of direct oral anticoagulants (DOACs) for the treatment of atrial fibrillation has ushered in an era of potential treatment options for these complex patients.

To review the clinical evidence underlying the use of DOACs for the treatment of patients with atrial fibrillation and ACS or PCI.

Three trials studied this particular patient population; WOEST showed that dual therapy with warfarin and clopidogrel decreased hemorrhage at 1 year compared with standard triple therapy (19.4 vs. 44.4% HR 0.36; 95% CI 0.26–0.50; P < 0.0001), without increasing thromboembolic events (11.1 vs. 17.6% HR 0.60; 95% CI 0.38–0.94; P = 0.025). PIONEER AF-PCI showed that 10–15 mg rivaroxaban plus P2Y₁₂ inhibitor for 12 months significantly lowered bleeding rates than standard triple therapy (16.8 vs. 26.7% HR 0.59; 95% CI 0.47–0.76; P < 0.001) and had equivalent rates of MACE. Finally, REDUAL-PCI compared two different doses of dabigatran (110 mg twice daily and 150 mg twice daily) plus P2Y₁₂ inhibitor with standard triple therapy and reported reduced ISTH bleeding with both doses; HR 0.52 with 110 mg dabigatran (95% CI 0.42–0.63, P < 0.001) and HR 0.72 with 150 mg dabigatran (95% CI 0.58–0.88; P = 0.002). The rate of the composite of thromboembolic events, death, or unplanned revascularizations was similar between pooled dabigatran dual therapy and triple therapy groups (13.7 vs 13.4% HR 1.04; 95% CI 0.84–1.29; P = 0.005).

Recent evidence shows that DOACs plus one antiplatelet agent can decrease bleeding in patients with atrial fibrillation undergoing PCI for ACS. Although not powered to detect non-inferiority or superiority, large studies suggest rivaroxaban 10–15 mg plus P2Y₁₂ inhibitor for 12 months or dabigatran 150 mg twice daily plus P2y12 inhibitor for 12 months will have similar rates of MACE and stent thrombosis as triple therapy. In patients who have contraindications to DOACs, the strategy of INR-adjusted warfarin plus clopidogrel appears to be safer than warfarin plus dual antiplatelet therapy.