The Relationship Between Grade of Ischemia, Success of Reperfusion, and Type of Thrombolytic Regimen

BACKGROUND: This study was aimed to determine whether the grade of ischemia can predict the success of reperfusion in patients treated with thrombolytic therapy (TT) for ST elevation myocardial infarction (STEMI).
MATERIAL AND METHODS: We enrolled 229 consecutive patients with diagnosis of STEMI and receiving TT. Patients were divided into 2 groups – grade 2 ischemia (GI2) and grade 3 ischemia (GI3) – according to initial electrocardiogram (ECG). As TT, fibrin-specific (tissue plasminogen activator (t-PA)) or non-fibrin-specific (streptokinase (SKZ)) regimens were used. Successful reperfusion was defined as >50% resolution of the maximal ST segment on 90-min ECG. We tried to evaluate whether the grade of ischemia could predict the success of reperfusion and if there were any differences in terms of successful reperfusion between different thrombolytic regimens.
RESULTS: The successful reperfusion rate was significantly higher in GI2 than GI3 (82.4% vs. 64.4% respectively, p=0.002). The success rate was lowest at anterior GI3 (55.8%). Although there was no significant difference between thrombolytic regimens in all groups (p=0.77), t-Pa was superior to SKZ in anterior GI3 (63,6% vs. 30%, p=0.061). In addition, in multivariate analysis, GI and infarct localization were found as independent predictors for successful reperfusion with TT (p=0.006 and p=0.042, respectively).
CONCLUSIONS: In the current study, we found that GI2 is an independent predictor for successful reperfusion in STEMI treated with TT. Fibrin specific regime should be preferred in anterior GI3.

Keywords: Electrocardiography, Multivariate Analysis, Myocardial Infarction - ultrasonography, Myocardial Ischemia - ultrasonography, Myocardial Reperfusion, Thrombolytic Therapy