A clinical trial of the effectiveness of water as a conductive medium in electrocardiography

A clinical trial was conducted in three hospitals to determine if common tap water is suitable for use as a conductive medium in electrocardiography (ECG). It compares two consecutive ECG recordings of 100 patients, the first recordings were obtained with water as the conductive medium, the second tracings used the electroconductive gel Redux Creme. Analysis involved comparison of the height of the R wave in lead V4 and tracing reports from a cardiologist 'blind' to the medium used. Results indicated that there was no statistically significant difference in the conductive ability of the two media. Analysis of the clinical performance of the media indicated that in 82% of the traces water was equal to or better than gel in clarity, and in 90% of traces water was equal to or better than gel in suitability for diagnosis. One implication of the study is the possibility of significantly reducing the cost of ECG procedures while ensuring the quality of tracings remains at a clinically acceptable level.