Development of QRS detection method for real-time ambulatory cardiac monitor

The primary goal of this research is to develop an affordable real-time ambulatory electrocardiogram (ECG) monitor prototype. The system consists of an analogue signal conditioner, a micro-controller, external RAM and ROM, and a PCMCIA flash memory card and interfacing chip. Researches are carried out in the ECG data compression and real-time diagnosis. For the purpose of ECG analysis, a reliable QRS detection algorithm with as little computation as possible has to be developed. This paper reports our works in the development of QRS detection algorithms. They are derived and improved from the first derivative method as described in the paper by Friesen et al. Our results show that the maximum slope detection, with the QRS onset selected when two successive values of slope exceed the threshold, is the best method.