Optimal placement of dual chest leads for deriving 12-lead/18-lead electrocardiograms and vectorcardiograms

Our aim was to develop and evaluate transformations for deriving standard 12-lead ECG, 18-lead ECG (with added V7-V9, V3R-V5R), and Frank VCG from lead sets using 3 limb electrodes at Mason-Likar sites and 2 electrodes at V1-V6 sites. The study population consisted of 290 normal subjects and 602 patients with previous myocardial infarction or ventricular tachycardia. Required ECG data were extracted from 120-lead recordings and transformation coefficients were derived by regression analysis. The ability of reduced lead sets to derive complete ones was assessed by 2 measures of fit: similarity coefficient and relative error. Results show that 6 out of 15 possible pairs of Mason-Likar chest leads (namely V1 & V4, V1 & V3, V2 & V5, V2 & V4, V3 & V6, and V3 & V5), used together with Mason-Likar limb leads, are best suited for reconstructing the complete 12-lead ECG and 18-lead ECG, as well as the VCG. In conclusion, our study shows that judiciously chosen reduced lead sets can approximate conventional ECG/VCG very satisfactorily