C. IMA
ÎFor IMA bypass grafting, the ACCP recommends aspirin, 75 to 162 mg/d, indefinitely (1A).
ÎFor IMA bypass grafting with no other indication for VKAs, the ACCP recommends against using VKAs (1C).
D. CHF
ÎFor congestive heart failure due to a nonischemic etiology, the ACCP recommends against routine use of aspirin or oral VKA (1B).
II. Patients at Risk
ÎThe ACCP recommends against the routine addition of clopidogrel to aspirin therapy in primary prevention (1A). For aspirin allergy with a moderate to high risk for a cardiovascular event, the ACCP recommends monotherapy with clopidogrel (1B).
ÎFor a moderate or higher risk for a coronary event (based on age and cardiac risk factor profile with a 10 year risk of a cardiac event of 10%), the ACCP recommends 75-100 mg/d of aspirin over either no antithrombotic therapy or VKA (2A).
ÎFor particularly high risk patients in whom INR can be monitored without difficulty, the ACCP suggests low-dose VKA with a target INR of approximately 1.5 over aspirin therapy (2A).
A. Women
ÎFor women < 65 years of age who are at risk for an ischemic stroke, and in whom the concomitant risk of major bleeding is low, the ACCP suggests aspirin at a dose of 75-100 mg/d over no aspirin therapy (2A).
ÎFor women > 65 years of age at risk for ischemic stroke or MI, and in whom the concomitant risk of major bleeding is low, the ACCP suggests aspirin at a dose of 75-100 mg/d over no aspirin therapy (2B).
Values and preferences: The recommendation of aspirin over VKA places a relatively low value on a small absolute reduction in coronary events and deaths and a relatively high value on avoiding the inconvenience, cost, and minor bleeding risk associated with oral VKA. The low target INR value required in primary prevention typically mandates less frequent monitoring; on average every 2 to 3 months and is associated with lower risk of bleeding. Patients, particularly those in the highest risk groups for whom systems permitting meticulous monitoring of anticoagulant therapy are available, those who place a relatively high value on small absolute risk reductions in coronary events, and those who are not influenced by an element of inconvenience and potential bleeding risk associated with VKA, are likely to derive the greatest overall benefit from administration of VKA rather than aspirin.
