The Reproducibility of Global Electrical Heterogeneity ECG Measurements

摘要

Background: Global electrical heterogeneity (GEH) is a useful predictor of adverse clinical outcomes. However, reproducibility of GEH measurements on 10-second routine clinical ECG is unknown. Methods: Data of the prospective cohort study of incident hemodialysis patients (n=253; mean age $54.6pm 13.5y$; 56% male; 79% African American) were analysed. Two random 10-second segments of 5-minute ECG recording in sinus rhythm were compared. GEH was measured as spatial QRS-T angle, spatial ventricular gradient (SVG) magnitude and direction (azimuth and elevation), and a scalar value of SVG measured by (1) sum absolute QRST integral (SAI QRST), and (2) QT integral on vector magnitude signal (iVMQT). Bland-Altman analysis was used to calculate agreement. Results: For all studied vectorcardiographic metrics, agreement was substantial (Lin‘s concordance coefficient >0.98), and precision was perfect (>99.99%). 95% limits of agreement were $pm 14^{circ}$ for spatial QRS-T angle, $pm 13^{circ}$ for SVG azimuth $pm 4^{circ}$ for SVG elevation, $pm 14 mV^{st}ms$ for SVG magnitude, and $pm 17 mV^{st}ms$ for SAI QRST. SAI QRST and iVMQT were in substantial agreement with each other. Conclusion: Reproducibility of a 10-second automated GEH ECG measurements was substantial, and precision was perfect.