The spatial QRS-T angle and the spatial ventricular gradient: Normal limits for young adults

We computed normal limits of the spatial QRS-T angle (SA) and the spatial ventricular gradient (SVG) in 660 normal resting ECGs (449 female / 211 male) recorded in healthy subjects aged 18-29 years. Values for males and females were compared, and normal limits for males from this study were compared to the normal limits for males, published previously in 1967. In females, the SA was sharper (females: 66 plusmn 25deg males: 80 plusmn 24deg, P<0.001) and the SVG magnitude was smaller (females: 81 plusmn 23 mVldrms; males: 110 plusmn 29 mVldrms, P<0.001) than in males. The SVG magnitude in males was larger than that published in 1967 (79 plusmn 28 mVldrms; P<0.001). SA and SVG depend strongly on gender. The newly calculated SVG magnitude in males differs strikingly from the 1967 value; explanations for this difference are given.