Background &Objective: Infarctian size is the most important prognostic factor in patients with acute myocardial infarction (AMI). Reperfusion therapy using thromboliatics is the most important measure in order to limit the infarction, size. Infarction size on the other hand, associates directly with left ventricular (LV) function. The presence of Q wave on electrocardiogram (ECG) after thrombolytic therapy is associated with increased mortality during first months after AMI. Moreover electrocardiographic changes after thrombolytic therapy can predict LV function. This study is an attempt to evaluate the relationship between electrocardiographic Q wave and LV function after thrmobolytic therapy in patients with MI.

  Methods: 176 patients with first episode of AMI (diagnosed based on WHO criteria) who were receiving streptokinase took part in this analytical study. ECG of the first day after admission and ECG of discharge day (usually the sixth day) were evaluated in terms of the presence of pathologic Q wave. LV function was evaluated by Echocardiography using Simpson method. The data were analyzed by SPSS program using chi-square test.

  Results: On discharge day 82.4% of the patients had pathologic Q wave and 17.6% were without it. 51.6% of patients without pathologic Q wave, had normal LV function (LVGF>55%) while 26.9% of them had Q wave (p= 0.001). 73.3% of males and 56.4% of females had Q wave on ECG.

  Conclusions: Presence of Q wave on ECG in patients with AMI after thrombolytic therapy correlates with LV function and indicates impaired LV function in these patients.