Objective:  To determine the accuracy of ST-Segment resolution on ECG for the success of thrombolysis of infarct-related artery in acute myocardial infarction, in comparison to angiography.

Methodology:Five hundred patients (311male and 189 females) with acute STEMI receiving streptokinase, within 12 hours of symptomswere included in the study via consecutive convenient non-probability sampling. ECG was recorded immediately after the patient arrived in the emergency unit of cardiology. ST-Segment elevation was recorded as in 1mm, 2mm, or >2 mm, and infarct related artery (IRA) was identified on ECG. Serial ECGs were analyzed for ST-Segment deviation in terms of ST-Segment elevation and resolution. The subsequent ECGs were recorded at 90 minutes after the administration of Streptokinase. ST-Segment resolution, which was recorded as percentage (>50%) resolution of ST-Segment elevation in the same lead. 

Results:Out of 500 participants, 239(47.8%) were Diabetic, 267(53.4%) hypertensive, 274(54.8%) smokers, 261(52.2%) had hyperlipidemia. Anterior wall myocardial infarction (MI) was the most common site 253(50.6%)and the commonest artery involved was the left anterior descending artery 241(48.2%) followed by right coronary artery in 146(29.2%)patients. ST-resolution of more than 50% on ECG was found in 320 (64.0%) participants. Thrombolysis in MI (TIMI) grade III flow in angiography was found in 211(61.8%) participants. The sensitivity of ST-Segment resolution on ECG after SK was 84%, specificity of 62%, positive predictive value was 75% and negative predictive value was 75%.

Conclusion:ST resolution on ECG after Streptokinase can predict infarct-related artery patency on coronary angiography. ST-Segment resolution on ECG has moderate sensitivity (84%) and specificity (62%) in the detection of TIMI III flow in infarct-related artery.

Keywords: angiography, ECG, patency, infarct-related artery, streptokinase