ECG Extraction Techniques: A Review

Abstract

Cardiovascular disease is growing exponentially day by day. Also, Electrocardiography (ECG) plays a vital role in monitoring heart health by providing certain information to a cardiologist, which would be helpful to detect the heart conditions such as stroke and arrhythmia. ECG is a graph of voltage against the time of the heart's electrical activity that can be extracted by connecting electrodes into the skin. Measuring the ECG of a particular person, to be precise a heart patient, easily from home without visiting hospitals is one of the emerging technologies. This is especially useful post-COVID years where visiting hospitals for non-COVID patients is difficult and also risky considering the contact of the coronavirus. Measuring the electrical activities of a heart is a complex task and the conventional method of 12 lead electrodes needs the help of the medical practitioner, is time-consuming, not user friendly, has negative effects on the skin, and cannot be used for continuous health monitoring applications. So, extensive research is ongoing to provide the novel method to extract the ECG wave from the person with less complexity, accuracy, and lesser cost, so that it can have real-world usage and help to detect the cardiac arrhythmia priorly and take necessary precautions. Nevertheless, various ECG extraction methods have been developed, with each of them having different complexity, accuracy, cost, and useful applications. For special applications like remote health monitoring systems, the accuracy and user-friendliness of the extraction method play a vital role, we can’t expect the person to have medical knowledge, nor a nurse or health practitioner will not be there for help. Hence in this paper, an attempt is made to discuss and compare the various available ECG extraction methods. Methods like conventional 12 wet Ag/AgCl electrodes method, Dual dry Ag/AgCl electrodes with Left Leg Drive method, and Dual Dry Electrode method have been discussed and compared concerning to its complexity, cost, and accuracy along with a brief about Electrocardiography (ECG) wave and its intervals for reference in the paper. And a possible novel way of extraction of the ECG signal using dual electrodes across the finger site for the applications like remote health monitoring systems is proposed based on its accuracy and user-friendly approach.