Low-molecular-weight heparins in acute myocardial infarction: rationale and results of a pilot study.
BACKGROUND
Antithrombotic adjuncts to fibrinolytic drugs for acute myocardial infarction increase the rate and speed of infarct artery recanalization.


OBJECTIVE
A low-molecular-weight heparin might be preferable to unfractionated heparin for this indication, as it has been shown to be in several other thrombus-related vascular disorders.


METHODS
We performed a pilot study in 20 patients, all receiving aspirin and recombinant tissue plasminogen activator. Randomization was to standard dose intravenous unfractionated heparin or enoxaparin (the first dose given intravenously and followed by a subcutaneous administration). The endpoint was stability of anticoagulant effect.


RESULTS
Enoxaparin produced stable therapeutic anti-Xa levels with minimal effect on activated partial thromboplastin times. Unfractionated heparin produced wide swings of these parameters, often outside desired levels.


CONCLUSIONS
Enoxaparin may be a better antithrombotic agent than conventional unfractionated heparin when used in conjunction with fibrinolytics.
Ross
A M
AM
Cardiovascular Research Institute, George Washington University, Washington, DC 20037, USA.
Coyne
K
K
Hammond
M
M
Lundergan
C F
CF
D001241:Aspirin / Q000627:therapeutic use; D004333:Drug Administration Routes; D004359:Drug Therapy, Combination; D017984:Enoxaparin / Q000008:administration & dosage / Q000627:therapeutic use*; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D009203:Myocardial Infarction / Q000097:blood / Q000188:drug therapy*; D010314:Partial Thromboplastin Time; D010865:Pilot Projects; D010960:Plasminogen Activators / Q000627:therapeutic use; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
D017984:Enoxaparin; D005343:Fibrinolytic Agents; D006495:Heparin, Low-Molecular-Weight; D010975:Platelet Aggregation Inhibitors; D011994:Recombinant Proteins; D010960:Plasminogen Activators; D010959:Tissue Plasminogen Activator; D001241:Aspirin