Early changes in ventricular repolarization after thrombolytic therapy in patients with acute myocardial infarction as indicators for prediction of epicardial coronary artery reperfusion.

Objectives: To investigate the relationship between early T-wave inversion after thrombolytic therapy and the likelihood of successful epicardial coronary reperfusion.

Subjects And Methods: Thrombolytic therapy was given to 195 patients with ST segment elevation due to acute anterior myocardial infarction (AMI). Coronary angiography was performed. Receiver operating characteristic (ROC) curve (grade of sensitivity versus false positive) was calculated using likelihood ratio method to identify the ideal cut-off values of the ventricular repolarization variables.

Results: Predictive indices showed 80% sensitivity, 83% specificity, 81% accuracy, 88% positive predictive value and 71% negative predictive value for early T-wave inversion after thrombolytic therapy. A good concordant agreement was noted between the data of coronary angiography and early T-wave inversion in the infarct-related ECG leads after thrombolysis (kappa coefficient kappa= 0.876). Stepwise multivariate analysis revealed that early T-wave inversion after thrombolytic therapy of AMI was significantly associated with a history of preinfarction angina, residual infarct-related coronary artery stenosis >50%, short time to thrombolytic therapy <90 min, and evening time for occurrence of thrombolysis (p < 0.05). The ROC curve data analysis showed that early T-wave inversion amplitude after AMI had 87% sensitivity and 84% specificity for predicting successful reperfusion, with an ideal cut-off value of 7.2 mm, while time of T-wave inversion had 80% sensitivity and 79% specificity, with an ideal cut-off value of 120 min.

Conclusion: The data indicate that early inversion of T wave after AMI is a statistically significant independent variable in predicting successful epicardial coronary thrombolysis status.