Clinical proof of practicability for an ECG device without any conductive contact

Abstract

Heart rhythm disturbances are common symptoms of several heart disorders. One of the most effective screening methods is the traditional electrode-based ECG. However, this examination can be both time- and resource-consuming. Capacitive-coupling ECG (cECG) screening--working without any conductive electrical contact with the patient--might help to shorten the time required for diagnosis. In this study, we examine the practicability of employing a non-contact capacitive ECG in a clinical setting. A total of 30 volunteer patients aged over 50 years without pacemakers were included in our trial, after obtaining their written informed consent and their medical history. A cECG as well as a conventional, conductive ECG were recorded simultaneously. In addition to mathematical analysis, ECG data were manually evaluated by two clinicians blinded to the recording method and patient conditions. Data from 30 patients were collected during our study, seven of whom had experienced myocardial infarction. The obtained cECG signals showed a high correlation with the simultaneously recorded Einthoven lead II of the conventional ECG. The values for heart rate, PQ and QT time periods correlated particularly well. Significant differences were observed with regard to QRS duration. Data recorded in the supine position contained less motion artefacts and, in particular, there were fewer breathing artefacts compared to data collected from those in a sitting position. Owing to the easy and quick application of the cECG system, the feedback from the examined patients was consistently positive. In conclusion, recording cECG data in a sitting position provided sufficient quality for screening purposes. Further studies will be needed for the evaluation of cECG appropriateness in diagnosing heart disease.