The synthesized vectorcardiogram resembles the measured vectorcardiogram in patients with dyssynchronous heart failure

•The vectorcardiogram (VCG) has regained interest in electrical dyssynchrony patients.•The VCG can be recorded or synthesized from the 12-lead electrocardiogram (ECG).•The synthesized VCG shows large resemblances with the recorded VCG.•This enables retrospective and prospective VCG analysis of previously recorded ECGs in CRT studies.

BackgroundThe use of vectorcardiography (VCG) has regained interest, however, original Frank-VCG equipment is rare. This study compares the measured VCGs with those synthesized from the 12-lead electrocardiogram (ECG) in patients with heart failure and conduction abnormalities, who are candidate for cardiac resynchronization therapy (CRT).MethodsIn 92 CRT candidates, Frank-VCG and 12-lead ECG were recorded before CRT implantation. The ECG was converted to a VCG using the Kors method (Kors-VCG) and the two methods were compared using correlation and Bland-Altman analyses.ResultsVariables calculated from the Frank- and Kors-VCG showed correlation coefficients between 0.77 and 0.90. There was a significant but small underestimation by the Kors-VCG method, relative bias ranging from − 1.9% ± 4.6% (QRS-T angle) to − 9.4% ± 20.8% (T area).ConclusionThe present study shows that it is justified to use Kors-VCG calculations for VCG analysis, which enables retrospective VCG analysis of previously recorded ECGs in studies related to CRT.