Benefits and Risks of Anticoagulation in Acute Coronary Syndrome

Abstract

Background: Both antiplatelets and anticoagulants are necessary in the management of acute coronary syndrome (ACS), although the exact proportion of antithrombotic effect that each drug and class should ideally provide remains a matter of ongoing study. Area of Uncertainty: Defining the best combination between the antiplatelet agents and oral anticoagulants (OACs) can be challenging. The choice is particularly important for special categories of patients with ACS who have an indication of a long-term OAC. Data Sources: A literature search regarding benefits and risks of anticoagulation in ACS was conducted through MEDLINE and EMBASE (past 20 years until September 2018). Therapeutic Advances: Many patients with ACS have an indication for long-term OACs. Those receiving dual antiplatelet therapy and anticoagulants are considered to be at a high bleeding risk. The addition of a vitamin K antagonist (VKA) imposes a target international normalized ratio of 2.0–3.0. When non-VKA oral anticoagulants are used, the lowest effective tested dose for stroke prevention should be applied. For most patients, triple therapy in the form of an OAC plus dual antiplatelet therapy [aspirin and P2Y12 inhibitors (usually clopidogrel)] should be considered for 3–6 months. Later, dual therapy (OAC plus aspirin or clopidogrel) should be considered for an additional 6 months. After 1 year, it is recommended that only the OAC is maintained. In cases of very high bleeding risk, triple therapy can be reduced to 1 month after ACS, continuing on dual therapy up to 1 year, and thereafter only anticoagulation. In general, the bleeding risk seems to be lower with non-VKA oral anticoagulants than VKA plus antiplatelet combination. Conclusions: Many risk factors for ischemic events and bleeding overlap. The clinician's challenges include monitoring patients' adherence and global assessment of the antithrombotic effect that incorporates antiplatelet and anticoagulant effects.

Management of antithrombotic therapy in patients with atrial fibrillation and acute coronary syndromes

“…Moreover, the thrombotic risk did not increase by omitting aspirin, however, the trial was small and not powered for these events- [56]. This study reconfirms that warfarin as OAC worked better than the combination of aspirin plus clopidogrelin AF patients and showed that, despite a lesser frequency of bleeding events, there was similar ischaemic clinical benefit in a 6-week TAT versus a 6-month TAT [55,57].…”

“…The primary safety end point for bleeding events was less frequent in both groups receiving rivaroxaban, as presented in Table 3. This trial adds new data on the use of low dose rivaroxaban in ACS patients and offersthe first clear signal for less bleeding with both reduced antithrombotic regimens-DAT (Rivaroxaban 15 mg/day and P2Y12 inhibitor), TAT with very low dose OAC (Rivaroxaban 2.5 mg twice daily) and DAPT [55,58]. PIONEER AF-PCI trial was not calibrated for ischaemic and thrombotic efficacy and low doses of rivaroxaban were not demonstrated to reduce stroke in AF patients [39,59].…”

“…The REDUAL trial only included patients undergoing PCI, about 50% of whom had ACS. Due to the study design, it is not clear whether the reduction in bleeding is dependent on the use of dabigatran or avoidance of aspirin [40,55]. Additionally, REDUAL PCI was not powered for efficacy in terms of ischaemic and antithrombotic events.…”

Protective Action of Betulinic Acid on Cerebral Ischemia/Reperfusion Injury through Inflammation and Energy Metabolic Homeostasis

“…Therefore, finding effective and reliable neuroprotective agents for stroke treatment is urgent. Clopidogrel, a platelet aggregation inhibitor, was reported to work as a stroke preventative drug in vivo by slowing platelet aggregation [19]. The present study examined infarct size, cerebral edema, neurological behavior, and inflammatory cytokine levels of MCAO rats and OGD/R-induced SHSY5Y cells after BA intervention.…”

“…Therefore, finding effective and reliable neuroprotective agents for stroke treatment is urgent. Clopidogrel, a platelet aggregation inhibitor, was reported to work as a stroke preventative drug in vivo by slowing platelet aggregation [19].The…”