Heart rate variability

Heart rate variability visualized with R-R interval changes
Electrocardiogram (ECG) recording of a canine heart that illustrates beat-to-beat variability in R–R interval (top) and heart rate (bottom).

Heart rate variability (HRV) is the physiological phenomenon of variation in the time interval between heartbeats. It is measured by the variation in the beat-to-beat interval.

Other terms used include "cycle length variability", "R–R variability" (where R is a point corresponding to the peak of the QRS complex of the ECG wave; and R–R is the interval between successive Rs), and "heart period variability".[1] Measurement of the RR interval is used to derive heart rate variability.[1]

Methods used to detect beats include ECG, blood pressure, ballistocardiograms,[2][3] and the pulse wave signal derived from a photoplethysmograph (PPG). ECG is considered the gold standard for HRV measurement[4] because it provides a direct reflection of cardiac electric activity.[5]

  1. ^ a b Johnston BW, Barrett-Jolley R, Welters ID (2020). "Heart rate variability: Measurement and emerging use in critical care medicine". Journal of the Intensive Care Society. 21 (2): 48–157. doi:10.1177/1751143719853744. PMC 7238479. PMID 32489411.
  2. ^ Brüser C, Stadlthanner K, de Waele S, Leonhardt S (September 2011). "Adaptive beat-to-beat heart rate estimation in ballistocardiograms". IEEE Transactions on Information Technology in Biomedicine. 15 (5): 778–786. doi:10.1109/TITB.2011.2128337. PMID 21421447. S2CID 10126030.
  3. ^ Brüser C, Winter S, Leonhardt S (2012). "Unsupervised Heart Rate Variability Estimation from Ballistocardiograms". 7th International Workshop on Biosignal Interpretation (BSI 2012), Como, Italy.
  4. ^ Schäfer A, Vagedes J (June 2013). "How accurate is pulse rate variability as an estimate of heart rate variability? A review on studies comparing photoplethysmographic technology with an electrocardiogram". International Journal of Cardiology. 166 (1): 15–29. doi:10.1016/j.ijcard.2012.03.119. PMID 22809539.
  5. ^ Lam E, Aratia S, Wang J, Tung J (2020-11-03). "Measuring Heart Rate Variability in Free-Living Conditions Using Consumer-Grade Photoplethysmography: Validation Study". JMIR Biomedical Engineering. 5 (1): e17355. doi:10.2196/17355. ISSN 2561-3278. S2CID 226305881.