Effects of reperfusion on late potentials of the QRS complex in acute myocardial infarction

Introduction. Cardiac rhythm disorders are common in patients after myocardial infarction. They play an important role in the course and in prognosis of this illness. Signal-averaged electrocardiogram (SAECGj is a non-invasive diagnostic method for the induction of sustained monomorphic ventricular tachycardia. Early opening of the infarct-related artery decreases occurrence of ventricular disorders in these patients. The aim of this study was to establish the connection between the late potentials of the ORS complex (SAECG) and unsuccessful reperfusion in patients with acute myocardial infarction (AMI). Material and methods. After myocardial infarction, presence of SAECG was examined in patients receiving reperfusion therapy in order to establish the treatment outcome. Late potentials in SAECG were determined by computer measurements in regard to criteria for its positivity. Results. The study group consisted of 33 patients. Out of 23 patients with successful reperfusion, only 6 (26.1%) had late potentials, in contrast to the group without reperfusion, 8 (80%) out of 10 patients had late potentials. Conclusion. Based on our results, we can conclude that there is a significant association between the presence of late ORS-complex potentials (SAECG) and unsuccessful reperfusion. Also, we can conclude that presence of late potentials is an independent predictor of infarct-related artery patency in patients with AMI treated with thrombolytic therapy. .