Prognostic Value of Standard Electrocardiographic Parameters for Predicting Major Adverse Cardiac Events after Acute Myocardial Infarction

Abstract

The prognostic value of electrocardiographic (ECG) variables in predicting major adverse cardiac events (MACEs) after acute myocardial infarction (AMI) in the era of modern therapy is unclear. This study was conducted to evaluate the prognostic significance of ECG parameters in predicting 1-year MACEs for AMI patients. Between January 2006 and January 2008, 529 AMI patients were included. ECG variables were analyzed from the ECG taken on discharge day. The 1-year MACEs were defined as death, nonfatal MI, and revascularization including repeat percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Mean follow-up duration was 360 ± 119 days. Of these patients, 497 (94%) patients provided complete follow-up data (355 males; 67 ± 12 years old). The rate of 1-year MACEs was 16%. In univariate analysis, heart rate, corrected QT interval, left ventricular (LV) hypertrophy, voltage (SV(1) + RV(5) ), lateral ST-depression (V(5-6) or I, aVL), pathologic Q wave (V(1-4) , V(5-6) ), ST-elevation (V(1-4) , V(5-6) or I, aVL), and T-wave inversion (V(1-4) , V(5-6) , or I, aVL) had a significant association with 1-year MACEs. In the Cox regression hazard model, lateral ST-depression (hazard ratio [HR] 2.260, 95% confidence interval [CI] 1.204 to 4.241, P = 0.011) and corrected QT interval (HR 1.007, 95% CI 1.002 to 1.011, P = 0.004) were independent predictors of 1-year MACEs. After adjustment for all risk variables, lateral ST-depression (HR 3.781, 95% CI 1.047 to 13.656, P = 0.042) was the only ECG variable that independently predicted 1-year MACEs. Lateral ST-depression on discharge day ECG is an independent predictor of 1-year MACEs after AMI.