Association between QRS score and myocardial viability in patients with stable angina pectoris

To evaluate whether the electrocardiography-derived QRS score is associated with myocardial viability (MV) assessed by fluorodeoxyglucose positron emission tomography (FDG-PET/CT) in patients with stable angina pectoris (SAP), reduced left ventricular ejection fraction (LVEF), and significant left anterior descending artery (LAD) stenosis. This retrospective cross-sectional study included 65 patients with SAP, LVEF ≤ 45%, significant LAD stenosis on angiography, and FDG-PET/CT performed for further MV assessment after an infarcted myocardial region had been reported on myocardial perfusion scintigraphy during the pre-revascularization evaluation. QRS scores were calculated using a modified Selvester scoring system. Binary logistic regression was used to evaluate factors associated with MV. MV was identified in 26 patients (40%). Patients with MV had lower QRS scores than those without MV (1.65 ± 1.38 vs. 4.54 ± 1.48, p < 0.001). Lower QRS score was associated with MV (OR: 0.29; 95% CI: 0.17 – 0.51; p < 0.001). For MV detection, QRS score yielded an AUC of 0.914 (95% CI: 0.84 – 0.98), and QRS score < 5 threshold showed 92.3% sensitivity and 56.4% specificity. In this selected cohort, lower QRS scores were associated with FDG-PET/CT-defined MV in the LAD territory. QRS scoring may provide adjunctive information during initial viability assessment, but should not replace established imaging-based evaluation.