Automatically computed ECG algorithm for the quantification of myocardial scar and the prediction of mortality

Background Myocardial scar is associated with adverse cardiac outcomes. The Selvester QRS-score was developed to estimate myocardial scar from the 12-lead ECG, but its manual calculation is difficult. An automatically computed QRS-score would allow identification of patients with myocardial scar and an increased risk of mortality. Objectives To assess the diagnostic and prognostic value of the automatically computed QRS-score. Methods The diagnostic value of the QRS-score computed automatically from a standard digital 12-lead was prospectively assessed in 2742 patients with suspected myocardial ischemia referred for myocardial perfusion imaging (MPI). The prognostic value of the QRS-score was then prospectively tested in 1151 consecutive patients presenting to the emergency department (ED) with suspected acute heart failure (AHF). Results Overall, the QRS-score was significantly higher in patients with more extensive myocardial scar: the median QRS-score was 3 (IQR 2–5), 4 (IQR 2–6), and 7 (IQR 4–10) for patients with 0, 5–20 and > 20% myocardial scar as quantified by MPI ( p < 0.001 for all pairwise comparisons). A QRS-score ≥ 9 ( n = 284, 10%) predicted a large scar defined as > 20% of the LV with a specificity of 91% (95% CI 90–92%). Regarding clinical outcomes in patients presenting to the ED with symptoms suggestive of AHF, mortality after 1 year was 28% in patients with a QRS-score ≥ 3 as opposed to 20% in patients with a QRS-score < 3 ( p = 0.001). Conclusions The QRS-score can be computed automatically from the 12-lead ECG for simple, non-invasive and inexpensive detection and quantification of myocardial scar and for the prediction of mortality. Trial-registration http://www.clinicaltrials.gov . Identifier, NCT01838148 and NCT01831115.