P2457Automated ECG quantification of myocardial scar in patients with and without conduction defects: correlation with myocardial perfusion imaging and clinical outcome in acute heart failure patients

Background: Myocardial scarring is associated with adverse outcomes due to heart failure and ventricular arrhythmias. The Selvester QRS-score was developed to estimate myocardial scarring from the 12-lead ECG. Manual calculation of the QRS Score however is difficult, lengthy and tedious. Automated calculation of the QRS-score, correlation with the reference standard of myocardial perfusion imaging (MPI) results and assessment of its prognostic value to predict adverse clinical outcomes are needed and enable its application in clinical practice. Methods: We prospectively enrolled 3'096 patients with suspected myocardial ischemia referred for MPI. The QRS-score was automatically calculated from a digital 12-lead ECG's recorded at presentation and the diagnostic value of the QRS-score to detect myocardial scar was assessed. We then prospectively tested the prognostic value of the QRS-score to predict all-cause mortality in 1'103 consecutive patients presenting to the emergency department (ED) with symptoms suggestive of acute decompensated heart failure (AHF). Results: Overall, the QRS-score increased significantly with the severity of the scar as quantified by MPI. There was a moderate positive correlation between QRS-score and MPI-scar (r=0.209, p<0.001). A stronger correlation was observed for ischemic and single-location scar burden. A QRS-Score ≥12 detected a reduced left ventricular ejection fraction with a specificity of 97% (95% CI 96.1–97.4%). Regarding clinical outcomes in patients presenting to the ED with symptoms suggestive of AHF, a greater QRS-score was significantly associated with a worse prognosis after 360 days (Survival rates 81%, 75%, 70% for patients with a QRS-score 0, 1–4, >4, p=0.036, Figure 1). In multivariable analysis, the prognostic value of the QRS-score was independent of other important predictors such as age, sex or QRS-duration (hazard ratio per 3 points increase 1.09, 95% CI 1.008–1.196).