A modern Wilson's Central Terminal electrocardiography database

Wilson's Central Terminal (WCT) is an artificially constructed virtual reference potential for surface electrocardiography (ECG). It is derived by averaging the voltage of the right arm (ΦR), left arm (ΦL), and left leg (ΦF), and is assumed to be steady and with negligible amplitude during the cardiac cycle. In order to measure WCT, in 1954, Bayley and Kinard encased volunteers inside a metal structure that was immersed in water for the duration of the recording. Due to the impracticality in measuring WCT using this method, it is an accepted methodological error in modern ECG. This study employed a novel ‘15-lead ECG device’ in which the ‘right leg’ is used as the ground reference terminal for measuring all signals. It was able to record WCT components (ΦR, ΦL, and ΦF) and a 12-lead ECG. Data from 85 patients (35 (41%) patients were female) at Campbelltown Hospital were recorded. Patients with pacemakers were excluded from the dataset. The average age of the study population was 65.31 years (SD 11.59). The absolute average amplitudes of WCT components among all patients were (ΦR = 0.076 mV, ΦL = 0.070 mV, and ΦF = 0.044 mV). Ten-second periods of recording without any artefacts was selected, and 413 10-second periods were extracted. It was found that recorded WCT is highly individual, and has standard ECG characteristics, including a P-wave, QRS complex, and T-wave.