Time correction and two channel recording in 24 hour electrocardiographic analysis

An improved technique for automatic monitoring and analysis of ECG recording is described. The system is based on standard commercial equipment but provides improved quantitative measurement of cardiac arrhythmias. This is done by using a simultaneous recording of a 100 Hz clock, which is used to correct for tape speed variations. Also increased immunity to artefacts is achieved by combining two ECG leads, coupled with signal analysis techniques. The problems arising from certain types of artefact are also discussed.