On the Equivalence of the 12-lead Ecg and the Vcg Representations of the Cardiac Electrical Activity

The electrocardiography (ECG) and vectocardiography (VCG) both describe the same phenomena: the temporal changes of the surface potentials resulting from cardiac electrical field. The ECG uses 12 leads positioned as it was found optimal from the medical point of view during a hundred years of practice. The VCG uses 3 channels connected to the psuedoorthogonal leads that placement is determined by the orthogonality of main Cartesian axes in consequence a three-dimensional recording is performed. This paper is devoted to the experimental verification of the likeness of the data provided by both recording techniques. Two different transforms re-mapping the ECG to the VCG domain and viceversa were studied with use of the set of 125 simultaneous ECG and VCG signals from the CSE Multilead Database. One of the possible technical interests of transforming the ECG signals to the VCG domain is reducing the data volume thanks to eliminating the information redundancy typical for ECG. Our results demonstrate that the forward and inverse transform has no perfect reconstruction property and some extent of distortion should be considered when applying this technique to the signal compression.