Measurement of 12-Lead ECG Using Multi-Orientation Electrodes on the Left Upper Arm in Healthy Subjects

Wearable technologies for cardiac monitoring have facilitated long-term electrocardiogram (ECG) data acquisition. This study presents an alternative approach for obtaining 12-lead associated ECG signals using electrodes strategically placed around the left upper arm (LUA-ECG). We validated whether this LUA-ECG configuration can reliably capture the morphological and quantitative characteristics of standard 12-lead ECG in healthy subjects.

The procedure was conducted in two sequential phases. Initially, standard 12-lead ECG and LUA-ECG were simultaneously recorded from thirty healthy adults. The LUA-ECG system captured 28 differential leads through a multi-electrode configuration strategically positioned around the arm. Among these 28 signals, eight key differential leads corresponding to the standard 12-lead configuration were selected to obtain the 12-lead ECG. In the subsequent phase, the fidelity of the obtained 12-lead ECG was evaluated by comparing it against the standard 12-lead ECG. The comparative analysis focused on key clinical features, including RR interval, PR interval, QRS duration, QT interval, and corrected QT interval (QTc).

The mean correlation of waveform from eight selected LUA-ECG signals compared with standard 12-lead ECG ranged 0.72 to 0.90. The mean absolute errors (MAE) for RR interval, PR interval, QRS duration, QT interval, and QTc of extracted 12-lead ECG derived from LUA-ECG ranged from 4.57 to 7.77 ms at a 500 Hz sampling rate.

The developed LUA-ECG system provides a reliable approach for long-term ECG monitoring. The extracted 12-lead ECG derived from LUA-ECG signal components effectively provides morphological and temporal features associated with conventional 12-lead ECG, demonstrating its potential for extended-duration monitoring applications.