Pharmacological treatment during AMI and in secondary prevention: the scientific evidence

Table 8. IV Anticoagulants + ASA.
STUDIES DRUG No. PATIENTS FOLLOW-UP VAR. P
During infarction
GISSI-2 (1990) [34] HEP + ASA vs ASA alone 12,381 35 DAYS -1% NS
ISIS-3 1992 [46] HEP + ASA vs ASA alone 41,299 35 DAYS -2.8% NS
 
META-ANALYSES No. STUDIES No. PATIENTS   VAR. P
Collins et al. (1997) [16] 26 68,000   -5% <0.05

 

1996 ACC/AHA GUIDELINES

  • Class I:
    • Patients undergoing percutaneous or surgical revascularization.
  • Class IIa:
    • Intravenously in patients undergoing reperfusion therapy with alteplase. Comment: The recommended regimen is 70 U/kg as a bolus at initiation of alteplase infusion, then an initial maintenance dose of ~15 µg/kg per hour, adjusted to maintain aPTT at 1.5 to 2.0 times control (50 to 75 seconds) for 48 hours. Continuation of heparin infusion beyond 48 hours should be restricted to patients at high risk for systemic or venous thromboembolism.
    • (new text)
    • Subcutaneously (7500 U twice daily) (intravenous heparin is an acceptable alternative) in all patients not treated with thrombolytic therapy who do not have a contraindication to heparin. In patients who are at high risk for systemic emboli (large or anterior MI, atrial fibrillation [AF], previous embolus, or known LV thrombus), intravenous heparin is preferred.
    • Intravenously in patients treated with nonselective thrombolytic agents (streptokinase, anistreplase, urokinase) who are at high risk for systemic emboli (large or anterior MI, AF, previous embolus, or known LV thrombus).
  • Class IIb:
    • Patients treated with nonselective thrombolytic agents, not at high risk, subcutaneous heparin, 7500 U to 12 500 U twice a day until completely ambulatory.
  • Class III:
    • Routine intravenous heparin within 6 hours to patients receiving a nonselective fibrinolytic agent (streptokinase, anistreplase, urokinase) who are not at high risk for systemic embolism.

1999 ACC/AHA GUIDELINES

  • Class IIa:
    • Intravenously in patients undergoing reperfusion therapy with alteplase. Comment: The recommended regimen is 60 U/kg as a bolus at initiation of alteplase infusion, then an initial maintenance dose of ~12 U/kg per hour (with a maximum of 4000 U bolus and 1000 U/h infusion for patients weighing >70 kg), adjusted to maintain aPTT at 1.5 to 2.0 times control (50 to 70 seconds) for 48 hours. Continuation of heparin infusion beyond 48 hours should be considered in patients at high risk for systemic or venous thromboembolism.
    • Intravenous unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) subcutaneously for patients with non-ST-elevation MI.
    • Subcutaneous UFH (eg, 7500 U BID) or LMWH (eg, enoxaparin 1 mg/kg BID) in all patients not treated with thrombolytic therapy who do not have a contraindication to heparin. In patients who are at high risk for systemic emboli (large or anterior MI, AF, previous embolus, or known LV thrombus), intravenous heparin is preferred.
    • Intravenously in patients treated with nonselective thrombolytic agents (streptokinase, anistreplase, urokinase) who are at high risk for systemic emboli (large or anterior MI, AF, previous embolus, or known LV thrombus).