As a cardiovascular pharmacist, you may be asked about the risk of stopping aspirin, clopidogrel, or other antiplatelet drugs too soon. This applies to the many patients with cardiovascular disease taking aspirin to prevent a recurrent event, or aspirin plus clopidogrel for acute coronary syndrome or after a stent.
Stopping these too soon can be catastrophic. For example, stopping aspirin in patients with a prior heart attack leads to 4 extra heart attacks per 1000 patients per year. Stopping clopidogrel within 30 days after a drug-eluting stent results in 25% of patients having a stent thrombosis instead of just 1%. Try to minimize inappropriate stoppage of antiplatelets. For stents, recommend aspirin plus clopidogrel (Plavix), prasugrel (Effient), or ticagrelor (Brilinta, Brilique) for AT LEAST one MONTH after a bare-metal stent, or at least one YEAR after a drug-eluting stent. But and this is very important, recommend aspirin INDEFINITELY. Recommend just 81 mg/day of aspirin, especially for patients on ticagrelor. Higher aspirin doses make ticagrelor LESS effective.
Advise physicians and dentists that antiplatelet drugs usually DON'T need to be stopped for procedures with a low bleeding risk (minor surgery, dental extraction, cataract surgery, endoscopy, etc). For stent patients, suggest trying to postpone procedures with a high bleeding risk until clopidogrel, prasugrel, or ticagrelor is stopped. If they can't wait, suggest continuing the drug through the procedure, if possible, or stopping the drug for a brief time. Recommend continuing aspirin for all but the riskiest surgeries. If the drug must be stopped, recommend stopping clopidogrel, ticagrelor, or aspirin 5 days prior, and prasugrel 7 days before surgery.
REFERENCES
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Ho PM, Peterson ED, Wang L, Magid DJ, Fihn SD, Larsen GC, Jesse RA, Rumsfeld JS. Incidence of death and acute myocardial infarction associated with stopping clopidogrel after acute coronary syndrome. JAMA. 2008 Feb 6;299(5):532-9. Available at: https://jamanetwork.com/journals/jama/fullarticle/181409
Grines, C.L., Bonow, R.O., Casey, D.E., Gardner, T.J., Lockhart, P.B., Moliterno, D.J., O’Gara, P. and Whitlow, P. (2007). Prevention of Premature Discontinuation of Dual Antiplatelet Therapy in Patients With Coronary Artery Stents. Circulation, 115(6), pp.813–818. Available at: https://doi.org/10.1161/circulationaha.106.180944
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