Influence of the artefact of computerised analysis of 24-hour electrocardiograms on the measurement of spectral components of heart rate variability

The authors investigate the effect of an artifact introduced by automated QRS complex recognition on two methods providing spectral heart rate variability (HRV) indices derived from 24-h electrocardiogram (ECG) recordings: (a) fast Fourier transformation and (b) peak-to-trough analysis. Both methods were used to measure the HRV spectra of 557 postmyocardial infarction patients before and after manual editing of the automated analysis. The low-, medium-, and high-frequency HRV components were calculated. For each method and each spectral component the results obtained from unedited and edited ECG analysis were compared. Both methods were substantially affected by the artifact. Spectral HRV analysis should be performed only on carefully verified 24-h ECG recognition