Abstract 8918: High QRS Score on Admission Strongly Predicts Impaired Myocardial Reperfusion in Patients With a First Anterior Acute Myocardial Infarction
Background: Baseline Q-wave presence, but not time from symptom onset, has been shown to be associated with increased risk in mortality and morbidity after acute myocardial infarction (AMI) treated with fibrinolysis or primary percutaneous coronary intervention (PCI). QRS score may reflect more quantitatively the stage of infarct evolution than Q-wave presence. The aim of this study is to examine the relation of admission QRS score to myocardial reperfusion in patients with AMI treated with reperfusion therapy.
Methods: We studied admission ECGs in 416 patients with a first anterior AMI treated with fibrinolysis or primary PCI within 6 h after symptom onset. Patients were classified into the 3 groups according to admission QRS score: low (<2, n=102), intermediate (2–4, n=228), and high (≥5, n=86) QRS score. Impaired myocardial reperfusion was defined as myocardial blush grade 0/1 on the final angiogram.
Results: Increase in admission QRS score was associated with longer time to admission, greater ST-segment elevation, more frequent proximal LAD occlusion, poorer collateral circulation, less frequent final TIMI 3 flow rate, higher peak creatine kinase level, and poorer left ventricular ejection fraction at discharge. After adjusting for baseline characteristics, multivariate analysis showed that high QRS score was the strongest predictor of impaired myocardial reperfusion. These findings were similar when stratified by time to admission (≤2 h, >2h).
Conclusions: In patients with a first anterior AMI treated with reperfusion therapy, the degrees of myocardial reperfusion differ depending on admission QRS score. High QRS score of ≥5 on admission ECG strongly predicts impaired myocardial reperfusion, even in those with early (≤2 h) presentation. These patients may be targeted for more aggressive therapeutic strategies to improve myocardial reperfusion.
- © 2010 by American Heart Association, Inc.