The relation of the frontal QRS axis to the anatomic position of the heart.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001827:Body Height; D001835:Body Weight; D004562:Electrocardiography / Q000592:standards; D006321:Heart / Q000033:anatomy & histology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D014672:Vectorcardiography