Anticoagulation Regimen After Thrombolysis in ST-Elevation Myocardial Infarction

Introduction to Anticoagulation Options

The European Society of Cardiology recommends that anticoagulation should be administered in patients treated with thrombolytics until revascularization (if performed) or during hospital stay for up to 8 days 1

The American College of Cardiology recommends enoxaparin as a first-line anticoagulant, administered as an intravenous bolus followed by subcutaneous injection, preferred over unfractionated heparin 1, 2
Enoxaparin dosing: intravenous bolus of 30 mg followed by 1 mg/kg subcutaneously every 12 hours, with dose reduction for patients over 75 years old 3

The American College of Cardiology recommends unfractionated heparin as a second-line anticoagulant, administered as an intravenous bolus adjusted by weight, followed by infusion, with a target activated partial thromboplastin time (aPTT) of 1.5 to 2.0 times control for 48 hours or until revascularization 1, 4

The American College of Cardiology recommends fondaparinux as a third-line anticoagulant, administered with an initial intravenous dose, followed by daily subcutaneous injections if estimated creatinine clearance is greater than 30 ml/min, until revascularization or during hospital stay (up to 8 days) 4

The American College of Cardiology recommends aspirin with a loading dose of 162-325 mg, followed by maintenance dose of 75-162 mg daily indefinitely, with a preferred maintenance dose of 81 mg daily 4, 5
The American College of Cardiology recommends clopidogrel with a loading dose of 300 mg (75 mg for patients over 75 years), followed by 75 mg daily, for a minimum of 14 days and ideally up to 1 year 4, 5

The European Society of Cardiology recommends immediate transfer to a center with percutaneous coronary intervention (PCI) capability for all patients after thrombolysis 1, 2
The American College of Cardiology recommends angiography and possible PCI immediately if thrombolysis has failed, or between 2-24 hours after successful thrombolysis 1, 4

For patients requiring triple therapy (warfarin, clopidogrel, and aspirin), the American College of Cardiology recommends a target international normalized ratio (INR) of 2.0-2.5, with low-dose aspirin (75-81 mg) and clopidogrel 75 mg daily, and close monitoring for increased bleeding risk 5
The American College of Cardiology recommends against the use of fondaparinux for primary PCI 1
The American College of Cardiology recommends that patients with renal insufficiency may require dose adjustments of enoxaparin or consideration of unfractionated heparin as an alternative 4
The American College of Cardiology recommends that triple antithrombotic therapy should be limited to specific situations (atrial fibrillation, left ventricular thrombus) due to high bleeding risk 5, 6