Results of the performance testing of purpose-built and PC-based electrocardiographs using a simple evaluation procedure

This paper presents the results of the evaluation testing of six 12-lead electrocardiographs, three purpose-built instruments and three of the recently introduced personal computer-based type (PC-based). As for PC-based electrocardiographs, three examples of the MRT systems, two examples of the 300 Hz CardioScope model and one prototype of the 1200 Hz CardioScope were examined but only results for one representative example of each are given here. It was of particular interest to compare the performance advantages and limitations of the PC-based electrocardiographs with that of instruments currently in use. A test procedure was developed that can be used by a medical technical department to evaluate an electrocardiograph before making a purchase decision. The procedure includes tests of frequency response, sampling rate, 50 Hz filter attenuation, gain and common mode rejection ratio (CMRR) plus tests based upon simulated electrocardiograms (ECGs). The procedure takes account of the AHA and ECRI recommendations for electrocardiograph checks and can be completed in less than two hours. The only equipment required being an ECG simulator and a signal generator. The results of this work show that purpose-built electrocardiographs meet all normal performance requirements, whereas the PC-based types, whilst having the potential to at least equal these requirements, currently exhibit software and hardware related problems.