Spatial peak and mean QRS-T angles: A comparison of similar but different emerging risk factors for cardiac death

Automatic identification of a stable QRST complex for non-invasive evaluation of human cardiac electrophysiology

“…The procedure proved feasible in 1080 (98.7%) of 1094 available recordings from a randomized population sample with equal proportions of women and men. The values of most VCG parameters differed significantly between women and men with the largest differences observed for the Peak and Mean QRS-T angles (48 and 30% larger in men), which are scientifically well-established risk-markers for cardiac death including SCD [2][3][4][5][6][7][8][9][10][11]. Men also had significantly larger heterogeneity (dispersion) of ventricular https://doi.org/10.1371/journal.pone.0239074.g004…”

“…Our ultimate goal for the development of a computerized/automatic VCG analysis is to provide its user with reliable VCG parameters for clinical purposes such as risk prediction regarding cardiac death including sudden cardiac death [2][3][4][5][6][7][8][9][10][11]. A suitable risk marker should have as good reproducibility as possible, including all technical aspects and the individual timedependent variability.…”

“…The CoroNet II system (Ortivus AB, Danderyd, Sweden) was used. Five electrodes were positioned around the chest (one in the back) aiming at the level of the 5th rib's insertion on the sternum, one in the neck, and one each on the left and right hip [11]. The electrodes on the back and neck (for Z-and Y-leads) were placed beside the spinous processes to optimize comfort.…”

“…Cardiac arrest and sudden cardiac death (SCD) is a major health problem and mainly due to an electrical disturbance although other etiologies exist [1]. Furthermore, electrical abnormalities such as wide QRS-T angles have in various cohorts shown prognostic value regarding cardiac events including SCD even beyond conventional demographic and clinical variables and are preferentially assessed from the Frank vectorcardiogram (VCG) [2][3][4][5][6][7][8][9][10][11][12].…”

“…The recording of the VCG differs mainly from standard electrocardiography (ECG) by placing one electrode on the back and one on the neck [11]. The VCG related information is based on three orthogonal leads (X, Y and Z) from which the P, QRS and T vector loops can be defined as well as one global QRST complex from QRST x , QRST y and QRST z ; S1 Fig.…”