The construction of the cardiac vector

Abstract

• 1. Two methods of constructing the cardiac vector, E, differ from each other by a factor /tr3.

• 2. The quantities measured in electrocardiography are essentially scalar in nature; from this fact the independence of the relationship e₁ + e₃ = e₂, of Einthoven's triangle, follows.

• 3. The significance of a transformation of V_L, V_R, V_F, e₁, e₂ and e₃ into vectors was discussed. The relationship between these vectors was obtained and it was shown that both methods of construction are valid and equivalent and can be equalized, if one makes certain adjustments to account for the difference in orientation of the two triaxial reference systems.