Abstract 10763: Electrocardiographic Markers of Myocardial Infarction Size
Background: Myocardial infarction (MI) size is an important determinant of mortality in post-MI patients, but the current gold standard test, cardiovascular magnetic resonance imaging (CMR), is expensive and not widely available. We sought to determine whether information from a readily available standard 12-lead electrocardiogram (ECG) could be utilized to estimate infarct size on CMR.
Methods: Patients with a clinical history of MI enrolled in the DETERMINE Trial and Registry who had CMR and ECG performed were included. Patients with left bundle branch block were excluded. Candidate ECGs markers, which may signify the presence of MI [Q waves (Qw), fragmented QRS (fQRS), and T wave inversion (TWI)] were examined for correlations with MI as a percent of LV (MI%) quantified by late gadolinium enhanced CMR. Contiguous Qw (cQw MI) and TWI (cTWI) in a coronary distribution and Qw and TWI in individual leads were examined separately in linear regression models.
Results: Of the 540 patients (mean age 62±11 years, 78% men, and mean LVEF=40±11%) included in the analysis, 334 had cQw MI, 225 had fQRS, 235 had cTWI, and 92 had none of these ECG markers. Patients without any of these ECG markers had an infarct size of 9.2±6.5% as compared to 14.6±7.6%, 18.6±9.1%, and 20.3±9.5% for those with one (n=175), two (n= 200), or all three (n= 73) ECG markers (P<0.001). By multivariate linear regression, the presence of cQwMI, fQRS, and cTWI were independently associated with an increase in MI% by 6.7%, 3.4%, and 4.9%, respectively. On per lead analysis, multivariate linear regression demonstrated a significant continuous relationship between MI% and the number of leads affected by Qw, fQRS, and TWI. MI% was 8.8% when all leads were free of candidate ECG markers and increased by 1.6%, 0.6%, and 0.6% for each lead affected by Qw, fQRS, and TWI, respectively (see table).
Conclusion: In patients with prior MI, Qw, fQRS, and TWI on ECG are independently associated with an increase in MI% measured by CMR.
Author Disclosures: D.C. Lee: None. C.M. Albert: None. D. Narula: None. A.H. Kadish: None. E. Wu: None. G. Panicker: None. J.J. Goldberger: None.
- © 2015 by American Heart Association, Inc.