A RANDOMIZED PILOT TRIAL OF BRIEF VERSUS PROLONGED HEPARIN AFTER SUCCESSFUL REPERFUSION IN ACUTE MYOCARDIAL-INFARCTION

Controversy exists as to whether and how long heparin treatment is necessary after infarct vessel recanalization. To determine the role of heparin, patients with suitable angiographic features after reperfusion therapy were randomly allocated to receive a brief infusion of intravenous heparin for ≤24 hours (group 1), adjusted to a partial thromboplastin time of 2 times control or a prolonged infusion for ≥72 hours (group 2), using the same titration mechanism. Patients were excluded for complex intimal dissections, large residual filling defects, less than Thrombolysis in Myocardial Infarction grade 3 flow pattern or >50% residual stenosis. Heparin was sustained except for discontinuation 2 to 4 hours before periaccess sheath removal, or if significant bleeding (≥2 units blood transfusion) occurred. The primary endpoints were 1-week patency determined by repeat catheterization or recurrent ischemia, or both, and the incidence of bleeding complications. Fifty patients were randomized, 25 in both groups. Baseline variables were similar; 14 group 1 and 15 group 2 patients received thrombolytic treatment; 20 patients in each group had coronary angioplasty. Two documented reoclusions occurred in both groups. Significant bleeding complications occurred in 0 of 25 (0%) group 1 versus 6 of 25 (24%) group 2 patients (p < 0.05). Thus, in low-risk patients after successful reperfusion, prolonged heparin therapy does not protect against rethrombosis and is associated with a significantly higher rate of bleeding complications. Therefore, prolonged heparin therapy for >24 hours does not appear to be justified in low-risk patients with successful reperfusion. © 1990.