Abstract 14577: Electrocardiogram Parameters for Predicting the Severity of Coronary Artery Disease in Non-ST Segment Elevation Acute Coronary Syndrome

Abstract

Background: Quantitative electrocardiogram (ECG) parameters have been found to correlate with severity of coronary artery disease (CAD). Thus, it may serve the purpose of risk stratifying patients with non-ST segment elevation acute coronary syndrome (NSTEACS). But little is known about the accuracy of each parameter.So, this study was done to assess the correlation of ECG parameters with severity of CAD in patients with NSTEACS and to compare the diagnostic accuracy among them. Methods: 178 patients with NSTEACS with left ventricular ejection fraction >50% were selected for the study after excluding patients with heart failure, arrhythmia, prior myocardial infarction or revascularisation. P wave peak time (PWPT), corrected QT dispersion (cQTd) and QT dispersion ratio (QTDR) was calculated in all patients. CAD severity was assessed visually by coronary angiography and calculating the syntax score. Results: PWPT, cQTd and QTDR were increased significantly in patients with left main (LM) or triple vessel disease (TVD) than others. These parameters also showed a strong positive correlation with the syntax score ( P<.001 ). Among these parameters, cQTd showed the best diagnostic accuracy (76% sensitivity and 64% specificity) to detect LM or TVD with a cut-ff value of 74 ms. Conclusion: PWPT, cQTd and QTDR may help to identify high risk patients with NSTEACS and early invasive procedure can be done to salvage a large area of myocardium at jeopardy. These may be particularly helpful to the physicians in periphery who have limited resources. Keywords: coronary artery disease, non-ST segment elevation acute coronary syndrome, P wave peak time, corrected QT dispersion, QT dispersion ratio