Heparin induced increase of t-PA antigen plasma levels in patients with unstable angina: no evidence for clinical benefit of heparinization during the initial phase of treatment.

Patients with unstable coronary artery disease were randomly treated either with a combination therapy consisting of nitrates and calcium-channel blockers without or with addition of clinical grade heparin administered subcutaneously; in order to evaluate the effect of heparin treatment on the fibrinolytic system, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) plasma levels were related to the clinical course of the disease. In heparinized patients thrombin time was prolonged more than 3-fold the normal range indicating effective heparin treatment. Heparinization led to a significant increase in t-PA antigen plasma levels (p less than 0.0001) within approximately four hours while PAI-1 activities remained unaltered. However, the measurable increase of the anticoagulant and pro-fibrinolytic activities of heparin did not result in a short-term benefit for the heparinized patients because the number of further ischemic attacks per patient during the observation period of three days was not different between the two study groups.

RCT Entities:   Population Interventions Outcomes