Anticoagulation and Antiplatelet Therapy in Hospitalized Patients

Introduction to Anticoagulation and Antiplatelet Therapy

• The American Heart Association recommends that patients with acute coronary syndromes (ACS) on heparin drip should be initiated on aspirin immediately in the Emergency Department with a loading dose of 162-325mg once the diagnosis of ACS is made or suspected 1, 2.
• After the initial loading dose, maintenance therapy with low-dose aspirin (75-100mg daily) should be continued for patients with ACS on heparin drip, as recommended by the American College of Cardiology 2.

Acute Coronary Syndromes Management

• The combination of aspirin with heparin is specifically indicated for ACS patients as it reduces mortality and recurrent ischemic events, according to the American Heart Association 1, 3.
• For patients who have undergone percutaneous coronary intervention (PCI), dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is recommended regardless of heparin therapy, as suggested by the American College of Cardiology 4, 5.

Post-PCI and Stroke Management

• After PCI, a daily aspirin dose of 81mg is preferred over higher maintenance doses due to lower bleeding risk, as recommended by the American Heart Association 5, 6.
• For patients with acute ischemic stroke, if treated with tPA (tissue plasminogen activator), aspirin should be delayed until after the 24-hour post-thrombolysis scan has excluded intracranial hemorrhage, according to the American Stroke Association 7, 8.

Bleeding Risk Considerations

• Dose-dependent increase in bleeding has been observed with aspirin, with major bleeding rates: 2.0% with <100mg ASA, 2.3% with 100-200mg, and 4.0% with >200mg daily, as reported by the American Heart Association 1, 9.
• The combination of anticoagulants (including heparin) with antiplatelet agents significantly increases bleeding risk, as noted by the American College of Cardiology 6.

Decision-Making Algorithm

• When determining the indication for heparin therapy, if for ACS, add ASA 81mg daily after loading dose, as recommended by the American Heart Association 1, 2.
• For patients transitioning from heparin to oral anticoagulation, if transitioning to warfarin for non-coronary indication, discontinue ASA if present, as suggested by the American College of Cardiology 6.