The effect of precordial leads displacement on P-wave morphology in body surface potential mapping
Résumé
The aim of this study was to investigate the variability of P wave morphology recorded in a close distance to precordial ECG leads. The study consisted of 60 cardiac patients. The ECG signals interpolated at points located at a distance up to 7 cm from the precordial lead location were compared to signals recorded from precordial leads. The 67-channel high-resolution ECG data were used. The distortions in ECG signals was increasing with the distance from precordial lead location, were specific for particular electrode and direction of displacement. Up to 5 cm there were not significant changes in values of correlation coefficient in all studied electrode positions. The P-wave morphology changes were prominent in values of delta parameter computed using the distribution function method and in values of normalized root mean square error beyond 2 cm distance from precordial leads V1 and V2. No significant ECG morphology changes up to 5 cm from location of leads V3, V4, V5 and V6 were observed. V1 electrode is more sensitive to vertical than to horizontal displacements in contrary to V2 electrode where horizontal shift in direction to V1 position play a key role.