Streptokinase and enoxaparin in the pre-hospital management of the ST-segment elevation acute myocardial infarction

Abstract

In a pilot study, safety and efficacy of an accelerated Streptokinase (SK) regimen (0.75 MU/10 min. repeated after 50 min. if no signs of coronary reperfusion were detected) in combination with enoxaparin was evaluated in the prehospital (preASENOX regimen) and in the in-hospital (in ASENOX regimen) phase of the ST segment elevation acute myocardial infarction (STAMI) and compared to the in-hospital standard SK plus Heparin (the StSK regimen).

Methods: A group of 262 consecutive patients (age 34-74 years) thrombolised within the first 6 hours after the onset of STAMI was divided in three subgroups according to the mentioned regimens: preASENOX (64 patients); in ASENOX (69 patients) and StSK (129 patients). Enoxaparin was administered i.v. 40 mg before the first dose of 0.75 MU of SK and 1 mg/kg every 12 hours for 5-7 days. Heparin was infused 1000 i.u./h 48-96 hrs. Three noninvasive reperfusion criteria were used: 1) Rapid cessation of the chest pain; 2) Rapid decreasing of the ST segment elevations by more than 50% from the initial value; 3) Rapid increasing of the CK and CK-MB with a peak within the first 12 hrs.

Results: The chest pain-thrombolysis time was 145 +/- 52 min in the preASENOX subgroup, significantly shorter as that in the ASENOX subgroup (172 +/- 73 min, p = 0.016) and the StSK one (168 +/- 80 min, p = 0.038). The ratios of the CR were 81.2%, 78.2% and 62.0%, respectively (preASENOX vs StSK p = 0.025; in ASENOX vs StSK p = 0.030). The inhospital mortalities were: 3.12% (preASENOX); 5.8% (inASENOX) and 10.8% (StSK)(non-significant differences). Only one case of ischemic stroke was registered (in the inASENOX subgroup). Symptomatic hypotension appeared more frequent in the preASENOX (39.06%), and inASENOX (43.47%) subgroups as compared to the SSK one (20.15%).

Conclusions: 1) The preASENOX and inASENOX regimens are safe, and lead toward a significant higher ratios of coronary reperfusion as compared to StSK regimen; 2) Our data suggest a very low mortality in patients treated with the preASENOX regimen. Further investigations (randomized studies) are needed for a definite conclusion.