The Value of ECG in the Prediction of Success of Thrombolysis in Patients with Acute Myocardial Infarction

摘要

12-Iead ECG remains a key test in the diagnosis of acute myocardial infarction (AMI). The earliest and most consistent ECG finding during acute ischemia is deviation of the ST segment , whereas prominent Q waves along with T wave inversion in the same lead distribution appear at a later stage of evolution. Most patients however , continue to demonstrate ECG changes from an infarction for a long period of time (months to years) , making thus routine ECG recordings a useful tool for the recognition of silent or atypical presentations of AMI as well.2 On the other hand , general agreement exists on the role of early thrombolysis (within 12 hours from the onset of symptoms , in the presence of ST segment elevations or newly developed LBBB) in reducing inf-arct size and preserving left ventricular contractile function. Compelling evidence suggests that infarct-related artery patency (TIMI grade 3 flow) at 90 minutes reflects successful reperfusion and is the prime correlate of improved survival. Interest in estimating the potential benefits of coronary thrombolysis has focused attention on the accurate determination of MI size through noninvasive techniques. The Sylvestcr-QRS scoring system quantifies infarct size using 32 points on surface ECG. With coverage of approximately 3% of total myocardial mass this method demonstrates good correlation with cardiac radionuclide techniques.