| Studies of thrombolysis in acute ST-elevation myocardial infarction (STEMI)
have focused on differences in outcome between groups receiving various regimes. Expedited
treatment may influence the efficacy of nonfibrin specific thrombolytic agents in
restoring early patency of the infarct-related artery (IRA), which is a major determinant
of survival after ST-elevation myocardial infarction (STEMI). Methods: We performed a
randomized double blind clinical trial comparing an accelerated infusion (1.5 MU/20 min;
group A, n = 200) with the conventional infusion (1.5 MU/60 min; group B, n = 100)
of streptokinase (SK) in 300 patients with their first episode of acute STEMI. Demographics,
clinical reperfusion rates, angiographic study findings, left ventricular ejection fraction
(LVEF), in-hospital morbidity and mortality and one year mortality were compared between
two groups. Results: Mean age was 59 ± 12 years (79% male). There were no differences
in baseline data between groups. Clinical, electrocardiographic and physiologic reperfusion
indices revealed significant faster and higher reperfusion rates and better preserved LVEF
at discharge in group A. Sixty-three percent of patients in either group underwent invasive
coronary angiography at a mean of 5 days with comparable findings. Atrial fibrillation,
malignant ventricular arrhythmias in the second day, in-hospital and late mortalities
rates occurred more frequently in group B patients. In multivariate analysis, accelerated
SK infusion was the only independent predictor of higher electrocardiographic reperfusion
(OR = 3.2, CI: 1.93–5.3, P < 0.001). Conclusions: The accelerated SK infusion regimen
of 1.5 MU in 20 min is safe and well tolerated with significantly faster and higher clinical
reperfusion rates, more preserved LV systolic function, less atrial and ventricular sustained
arrhythmias, and less in-hospital and 1 year mortality rates in acute STEMI. |