Frank electrocardiograms.

Frank electrocardiograms were recorded in 426 schoolchildren (225 girls, 201 boys) aged 10 to 14 years, planar vectorcardiograms projected onto the horizontal and left sagittal planes were constructed. Spatial magnitude of instantaneous QRS vector end-points in 10 ms intervals of QRS duration, and of maximum QRS vector, as well as X, Y, Z coordinates of instantaneous QRS vector end-points in 10 ms intervals of QRS duration, and of the maximum QRS vector were analyzed in relation to weight, height and BMI. The initial part of VCG loop was not influenced by age and anthropometric parameters, respectively. The spatial QRS vector magnitude at the 30 ms of QRS decreased significantly with age and height. From the 40 ms of QRS duration the VCG parameters were significantly related to anthropometric parameters. Vectorcardiographic parameters were more influenced by the anthropometric parameters then by age.