Effects of automatic ectopy exclusion on the analysis of heart rate variability using a percentile exclusion rule

Heart Rate Variability (HRV) is a widely used tool to study the autonomic control of the heart. Since the measurement should be performed using sinus beats only, non-sinus intervals (NSI), episodes of noisy data and ectopy, must be excluded. We studied the automatic detection of NSI by means of a Percentile Exclusion Rule (PER) in several patient categories and compared this to the gold standard "manual review" of the data. We concluded that automatic detection of NSI is troublesome and can lead to large differences in the outcome of HRV analysis. Manual review of the ECG is mandatory to obtain reliable HRV results.