Review of ECG Analysis

Abstract

In 1887, Augustus D. Waller published the _rst human electrocardiogram (ECG) recorded with a capillary electrometer. Subsequently, Willem Einthoven invented a more sensitive galvanometer for producing ECG using a _ne quartz string coated in silver. He invented the lead system for ECG recording and identi_ed the _ve deection points in the cardiac cycle by naming them P, Q, R, S and T which are still being used in the present standards (see Fig. 1.2). Einthoven also started transmission of ECG from hospital to his laboratory on telephone lines [33]. Since then a huge knowledge base has been generated covering clinical and engineering aspects of electrocardiography. Since last few decades electronic recorders have been developed for digital recording of the ECG signal. In recent years the ECG recorders are available in a much compact form so that the user can wear it for ECG recording without much of obstruction in the routine activities. Recently, the wearable ECG recorders (W-ECG) are becoming very popular because of their low cost, long term recording capability and ease of use.