Antiplatelet drugs are the drugs of choice for prevention and treatment of arterial thrombosis. Anticoagulants are the drugs of choice for prevention and treatment of venous thromboembolism and for prevention of cardioembolic events in patients with atrial fibrillation.

The standard antithrombotic therapy for treatment of patients with acute coronary syndrome (ACS) is dual antiplatelet therapy with aspirin and clopidogrel (Plavix) or another thienopyridine, plus a parenteral anticoagulant while the patient is hospitalized, followed by antiplatelet therapy alone after discharge. The addition of the oral anticoagulant warfarin (Coumadin, and others) to dual antiplatelet therapy is generally not recommended for this indication because of fluctuations in its anticoagulant effect and the risk of bleeding. A recently published trial found that addition of...

One of our readers has suggested that more attention should have been paid to a study comparing the antiplatelet effects of immediate-release and enteric-coated aspirin that appeared in Circulation last year.1 The safety benefits of enteric-coated aspirin are unclear. It may protect against dyspepsia, but not against major gastrointestinal bleeding, which is thought to be mainly a systemic effect of prostaglandin inhibition.ANTIPLATELET EFFECTS OF ASPIRIN — Aspirin irreversibly acetylates cyclooxygenase-1, blocking thromboxane synthesis and inhibiting platelet activation and aggregation for...

Atrial fibrillation increases the risk of thromboembolic stroke. Anticoagulant therapy can reduce this risk and is recommended for patients with atrial fibrillation and one or more of the following: congestive heart failure, hypertension, age ≥75 years, diabetes, or prior stroke or transient ischemic attack (CHADS₂ score ≥1).

The FDA has approved apixaban (Eliquis – Bristol-Myers Squibb/Pfizer), an oral direct factor Xa inhibitor, for prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. It is the third new oral anticoagulant to be approved for this indication as an alternative to warfarin.

Anticoagulants are the drugs of choice for treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE), collectively referred to as venous thromboembolism (VTE).

A reader has asked us to review the choice of drugs for heparin-induced thrombocytopenia (HIT), a prothrombotic state with high morbidity and mortality. Three recent publications have made somewhat different recommendations on its treatment.

The FDA has approved use of Kcentra (CSL Behring), a human-derived 4-factor prothrombin complex concentrate (PCC), for urgent reversal of warfarin anticoagulation in adults with acute major bleeding. It is the only 4-factor PCC available in the US.

The Interruption of Anticoagulation section of our article on Treatment of Atrial Fibrillation cited the recommendations of the American College of Chest Physicians on perioperative management of antithrombotic therapy (JD Douketis et al. Chest 2022; 162:e207). A reader suggested that our general statement on when to discontinue an oral anticoagulant would have benefited from inclusion of the recommendations of the American College of Cardiology/American Heart Association (JA Joglar et al. Circulation 2024; 149:e1). Recommendations for periprocedural management of oral anticoagulant therapy...

Recent guidelines from the American Heart Association and American Stroke Association reviewed antithrombotic therapy options for secondary prevention of stroke in patients who have had a stroke or transient ischemic attack (TIA).