Arrhythmia due to reperfusion after thrombolytic therapy in patients with acute myocardial infarction

Objective: The aim of this study was to determine the relation between the incidence and frequency of ventricular arrhytmias and the time course of ST-segment changes in patients with successful thrombolysis. Method: This study included 46 patients (31 males 53±12 years) with acute myocardial infarction (MI) who were treated with streptokinase (SK Group) and 41 MI patients (27 males 55±12 years) who did not receive any thrombolytic agent (Control Group). Electrocardiograms were obtained 90 minutes 6, 12, 18, 24, 48 and 72 hours after thrombolytic therapy and reduction in ST elevation at 90 minutes was calculated. All patients had wall motion abnormalities. Results: Overall arrhythmias were observed in 67% (n: 31) of  patients in SK group compared to 63% (n:26) in control group (p=0.05). In subgroup analysis of SK group ventricular tachycardia (VT) was more frequent (37%) in patients with more than 50% reduction in ST elevation at 90 minutes compared with in other subgroups of patients (p<0.01). Postinfarction angina and systolic dysfunction were more frequent in the control group compared to the SK group (p<0.05). Conclusion: Our results suggest that reperfusion with fibrinolytics or the faster reflow may induce ventricular arrhythmias. However, it can also prevent  the impairment in systolic function of the left ventricle. Key words: Myocardial infarction, thrombolysis, reperfusion,  arrhythmia