A robust, simple and reliable measure of heart rate variability using relative RR intervals

Background: Heart Rate Variability (HRV) is a physiological marker of the autonomic activity of the heart. For patients with cardiological diseases it has been used for risk stratification and health prediction. Other applications extend from psychology to sports science. However, in case of heart rate changes many standard measures are unreliable. Methods: A new geometric measure for HRV is introduced. It is based on relative RR intervals, the difference of consecutive RR intervals weighted by their mean. Results: The proposed measure is simple, robust and reasonable for computing HRV. It can be applied even to short RR sequences with artifacts and missing values.