Background: Recently, a simple ECG score (DETERMINE score) has been proposed for the estimation of myocardial scar in patients with ischemic cardiomyopathy. We sought to evaluate the clinical usefulness of the DETERMINE score for the assessment of myocardial infarct size (IS) as well as microvascular obstruction (MVO), in the setting of acute ST-elevation myocardial infarction (STEMI).

Methods: This observational study enrolled 423 patients with acute STEMI (median age 56, 17% women), revascularized by primary percutaneous coronary intervention (PCI). For evaluation of the DETERMINE and Selvester scoring system (an established but complex ECG score for IS estimation), ECG was conducted before discharge (median: 4 [interquartile range 2-6] days). Cardiac magnetic resonance (CMR) was conducted within a week after infarction for determination of IS and MVO.

Results: Median DETERMINE score of the overall cohort was 8 points (interquartile range: 5-11). Patients presenting with a score ≥ 8 points had more often anterior infarct localization (64% vs. 29%, p<0.001) and higher peak levels of high-sensitivity cardiac Troponin T (hs-cTnT) (6957 ng/l vs. 3117 ng/l, p<0.001), high-sensitivity C-reactive protein (hs-CRP) (28 mg/l vs. 20 mg/l, p<0.001) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (1553 ng/l vs. 779 ng/l, p<0.001). In linear and binary multivariable logistic regression analysis, the DETERMINE score remained independently associated with IS (odds ratio [OR]: 1.09, 95% confidence interval [CI] 1.02 to 1.17, p=0.014) and MVO (OR: 1.12, 95% CI 1.04 to 1.21, p=0.003), after adjustment for Selvester score and clinical indicators of IS (hs-cTnT, hs-CRP, NT-proBNP, TIMI flow pre-, and post-interventional PCI, anterior infarct localization).

Conclusions: In patients undergoing PCI for acute STEMI, the DETERMINE score provides an easy and inexpensive tool for appropriate estimation of infarct severity as determined by CMR.