Statistical analysis of quantitative electrocardiographic signals with standard limb leads: Influences of gel use, subject positions, and electrodes configurations

Abstract

An electrocardiogram records the heart’s electrical activity that provides helpful information on the cardio electrophysiological process. One cycle of cardiac contraction and relaxation produces the basic waves that consist of a P wave (atrial depolarization), a QRS complex (ventricular depolarization), and a T wave (ventricular repolarization). In this study, the quantitative electrocardiographic signals from six adult females aged 19 to 22 years in a relaxed state were measured using Cobra4 Electrophysiology with standard limb leads. Six conditions of the experiments were carried out for each subject to investigate the influence of gel use, subject positions, and electrodes configurations on electrocardiographic signals parameters: amplitude, duration, RRinterval, and correlation coefficient between two signals. It was obtained that the gel did not significantly influence the results for subjects when sitting but marginally influenced some electrocardiographic parameters for some individual subjects in lying positions. The subject positions influenced marginally for RRinterval. Electrode configurations are found to be related to the positive or negative deflection of the resulting electrocardiographic signals. All the measurements showed that two data sets of the ECG signals have a strong correlation for each subject in each condition.