Warfarin After Anterior ST-Elevation Myocardial Infarction

Summary

Following severe heart attacks involving the front wall of the heart (anterior myocardial infarction), patients are at risk of developing blood clots in the main pumping chamber that can cause a stroke. In the past, studies have shown that a blood thinner (warfarin) can decrease the risk of stroke and clot formation if administered to patients after an anterior myocardial infarction. However, in today's current practice, certain heart attack patients are commonly treated with two blood-thinning medications (aspirin and clopidogrel) to prevent recurrent heart attacks. Thus, a clinical problem is created as physicians are not clear how to treat patients after an anterior myocardial infarction who are at risk of a clot but require aspirin and clopidogrel to keep their blood vessels open. Adding warfarin to the combination of aspirin and clopidogrel will possibly decrease the risk of stroke but increase the risk of bleeding. Currently, there is no good evidence to help guide physicians. As demonstrated by a survey done at the Hamilton Health Sciences, there is a fifty/fifty split between physicians who use dual (aspirin and clopidogrel) versus triple (aspirin, clopidogrel, and warfarin) therapy in the treatment of similar patients as described above. The purpose of this study is to address the bleeding and stroke complications in patients after a severe anterior myocardial infarction. Half of the eligible patients will receive dual therapy and half will receive triple therapy. We will compare the incidence of stroke, blood clots, and bleeding complications between the two groups at 3 months.

Timeline

Start

2006-11

Primary completion

2008-01

Completion

2008-01

Publications

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• Background Sabatine MS, Blake GJ, Drazner MH, Morrow DA, Scirica BM, Murphy SA, McCabe CH, Weintraub WS, Gibson CM, Cannon CP. Influence of race on death and ischemic complications in patients with non-ST-elevation acute coronary syndromes despite modern, protocol-guided treatment. Circulation. 2005 Mar 15;111(10):1217-24. doi: 10.1161/01.CIR.0000157733.50479.B9.
• Background Antman EM, Anbe DT, Armstrong PW, Bates ER, Green LA, Hand M, Hochman JS, Krumholz HM, Kushner FG, Lamas GA, Mullany CJ, Ornato JP, Pearle DL, Sloan MA, Smith SC Jr, Alpert JS, Anderson JL, Faxon DP, Fuster V, Gibbons RJ, Gregoratos G, Halperin JL, Hiratzka LF, Hunt SA, Jacobs AK; American College of Cardiology; American Heart Association Task Force on Practice Guidelines; Canadian Cardiovascular Society. ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Revise the 1999 Guidelines for the Management of Patients with Acute Myocardial Infarction). Circulation. 2004 Aug 31;110(9):e82-292. No abstract available.

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