The Controversy of Heparin Therapy as an Adjunct to Thrombolysis in Acute Myocardial Infarction

Abstract

Heparin is used routinely in the US as adjunct therapy for prevention of reocclusion after thrombolysis during acute myocardial infarction. A review of the literature shows controversy over the efficacy of heparin following thrombolysis. Both beneficial and a lack of beneficial effects have been reported with heparin. From a pathophysiologic viewpoint, there appears to be a need for full heparinization in the postlytic period because the residual stenosis is highly thrombogenic. However, optimal dose, time, and mode of heparin therapy has not been defined. Despite a lack of definitive data, it seems reasonable to administer intravenous heparin immediately after thrombolytic therapy to achieve a partial thromboplastin time 1.5–2.0 times control that is concurrent with an antiplatelet agent such as aspirin. These recommendations are consistent with the consensus opinion of the American College of Cardiology and the American Heart Association.