RESUMO
BACKGROUND: The presence of pathologic Q waves on admission electrocardiogram (ECG) in patients with anterior ST-elevated myocardial infarction (STEMI) has been related to adverse cardiac outcomes. Our study evaluates the prognostic value of QRS complex and Q waves in patients with STEMI undergoing percutaneous coronary intervention. METHODS: We prospectively analyzed the specific characteristics of QRS complex and pathologic Q waves on admission and on discharge ECG in 144 patients hospitalized for anterior STEMI. We correlated these findings with the development of left ventricular systolic dysfunction (LVSD), appearance of heart failure (HF) or death during follow-up, and levels of several biomarkers obtained 6 months after the index event. RESULTS: Multivariate logistic regression analysis showed that QRS width (odds ratios [OR] 1.05, p = .001) on admission ECG and the sum of Q-wave depth (OR 1.06, p = .002) on discharge ECG were independent predictors of LVSD development. Moreover, QRS width on admission ECG was related to an increased risk of HF or death (OR 1.03, p = .026). Regarding biomarkers, QRS width on admission ECG revealed a statistically significant relationship with the levels of NT-pro-BNP at 6 months (0.29, p = .004); the sum of Q-wave depth (0.27, p = .012) and width (0.25, p = .021) on admission ECG was related to the higher levels of hs-cTnI; the sum of the voltages in precordial leads both on admission ECG (-0.26, p = .011) and discharge ECG (0.24, p = .046) was related to the lower levels of parathormone. CONCLUSIONS: Assessment of QRS complex width and pathologic Q waves on admission and discharge ECGs aids in predicting long-term prognosis in patients with STEMI.
