The low-molecular-weight heparin dalteparin as adjuvant therapy in acute myocardial infarction: The ASSENT PLUS study

Rapid reperfusion of an infarct-related artery reduces the extent of myocar dial damage and improves survival in acute myocardial infarction (AMI). Cur rently, anticoagulant treatment with unifractionated heparin (UFH) is used as adjuvant therapy to fibrinolytic treatment. The low-molecular-weight hep arin (LMWH) dalteparin is at least as effective as UFH in unstable coronary artery disease. The ASSENT PLUS trial was carried out to evaluate whether dalteparin is as effective as UFH as an adjunct to recombinant tissue-plasm inogen activator (rt-PA) and aspirin in obtaining patency and Thrombolysis in Myocardial Infarction (TIMI)-3 flow in patients with AMI. The primary as sessment of this phase II trial was TIMI now, determined by coronary angiog raphy. Patients with ST-elevation MI were randomized to receive aspirin and either rt-PA and UFH for 48 h, or rt-PA and dalteparin for 4 to 7 days. Ev aluation was by TIMI flow after 4 to 7 days and clinical events (death, rei nfarction, or revascularization) up to 30 days. There was a clear trend tow ard greater TIMI 3 flow with dalteparin compared with UFH. There was signif icantly less TIMI0-1 flow or thrombus in the dalteparin group. Bleeding rat es were similar. The occurrence of reinfarction was reduced during daltepar in treatment. These findings suggest that dalteparin could be substituted f or UFH as an adjunct to rt-PA/aspirin in the management of patients with AM I.