The use of heart rate variability analysis to detect arrhythmias in horses undergoing a standard treadmill exercise test.
Abstract: Little is known about normal heart rate variability (HRV) in horses during exercise. It can be difficult to separate premature beats from normal beat-to-beat variation at higher heart rates. Objective: The aim was to quantify HRV in healthy horses during a high-speed treadmill-standardized exercise test (HSET) and to compare with the HRV in horses observed to have arrhythmias during exercise. Methods: Thirteen healthy horses (Group H), 30 horses with arrhythmias (Group A), and 11 horses with poor performance but no observed arrhythmias (Group O). Methods: Prospective, observational study. All horses performed a HSET with simultaneous electrocardiograph (ECG) recorded. The ECGs were corrected for artifacts, and arrhythmias noted. Percent instantaneous beat-to-beat cycle length variation (% R-R variation) was calculated, and HRV analyses were performed on trot, canter, and recovery segments. Results: Group H showed between -4.4 and +3.8% R-R variation during trot and between -6.1 and +5.4% R-R variation during the canter phase of the HSET. Group A had significantly larger maximum and 1st percentile R-R shortening and lengthening compared with Group H and Group O during the recovery phase where most arrhythmias were observed. During recovery, a cutoff of 6% maximum % R-R shortening predicted the presence of arrhythmia with 88% sensitivity and 97% specificity and likelihood ratio of 26. Conclusions: Healthy horses have little instantaneous R-R variation during exercise. If a cardiac cycle shortens more than 6% from the previous cycle during the recovery phase, this R-R interval is likely to represent an arrhythmic event.
© 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Publication Date: 2018-12-05 PubMed ID: 30520119PubMed Central: PMC6335521DOI: 10.1111/jvim.15358Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research involves using heart rate variability (HRV) analysis to detect arrhythmias in horses during a high-speed treadmill-standardized exercise test. The study found that healthy horses have minimal heart rate variation during exercise, and that a cardiac cycle that shortens more than 6% from the previous cycle during the recovery phase likely indicates an arrhythmic event.
Objective of the Research
- The primary goal of the research was to quantify heart rate variability in healthy horses during a high-speed treadmill-standardized exercise test, and compare those results with horses known to have arrhythmias during exercise.
Methodology
- The research involved three groups of horses: 13 healthy horses (Group H), 30 horses with arrhythmias (Group A), and 11 horses with poor performance but without observed arrhythmias (Group O).
- All participating horses performed a high-speed treadmill-standardized exercise test while their electrocardiograph (ECG) was recorded. After the ECGs were corrected for artifacts, any arrhythmias were noted.
- Researches calculated the percent of instantaneous beat-to-beat cycle length variation (% R-R variation) and performed heart rate variability analyses on trot, canter, and recovery segments.
Results of the Study
- Healthy horses (Group H) showed between -4.4 and +3.8% R-R variation during trot and between -6.1 and +5.4% R-R variation during the canter phase of the treadmill exercise test.
- The horses with arrhythmias (Group A) had significantly larger maximum and 1st percentile R-R shortening and lengthening compared to Groups H and O during the recovery phase—where most arrhythmias were observed.
- During recovery, a cutoff of 6% maximum % R-R shortening predicted the presence of arrhythmia with 88% sensitivity and 97% specificity, resulting in a high likelihood ratio of 26.
Conclusions Derived From the Study
- Healthy horses exhibit minimal instantaneous R-R variation during exercise. Should a cardiac cycle shorten by more than 6% from the previous cycle during the recovery phase, the study concludes that it likely represents an arrhythmic event.
Cite This Article
APA
Frick L, Schwarzwald CC, Mitchell KJ.
(2018).
The use of heart rate variability analysis to detect arrhythmias in horses undergoing a standard treadmill exercise test.
J Vet Intern Med, 33(1), 212-224.
https://doi.org/10.1111/jvim.15358 Publication
Researcher Affiliations
- Equine Department, Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
- Equine Department, Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
- Equine Department, Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
MeSH Terms
- Animals
- Arrhythmias, Cardiac / diagnosis
- Arrhythmias, Cardiac / physiopathology
- Arrhythmias, Cardiac / veterinary
- Case-Control Studies
- Exercise Test / veterinary
- Female
- Heart Rate / physiology
- Horse Diseases / diagnosis
- Horse Diseases / physiopathology
- Horses / physiology
- Male
References
This article includes 25 references
- Eggensperger BH, Schwarzwald CC. Influence of 2nd-degree AV blocks, ECG recording length, and recording time on heart rate variability analyses in horses.. J Vet Cardiol 2017 Apr;19(2):160-174.
- Ille N, Erber R, Aurich C. Comparison of heart rate and heart rate variability obtained by heart rate monitors and simultaneously recorded electrocardiogram signals in nonexercising horses. J Vet Behav 2014;9:341‐346.
- van Vollenhoven E, Grant CC, Fletcher L. Repeatability and reliability of heart rate variability in healthy, adult pony mares. J Equine Vet Sci 2016;46:73‐81.
- Flethøj M, Kanters JK, Pedersen PJ, Haugaard MM, Carstensen H, Olsen LH, Buhl R. Appropriate threshold levels of cardiac beat-to-beat variation in semi-automatic analysis of equine ECG recordings.. BMC Vet Res 2016 Nov 28;12(1):266.
- Hamlin RL, Klepinger WL, Gilpin KW, Smith CR. Autonomic control of heart rate in the horse.. Am J Physiol 1972 Apr;222(4):976-8.
- Physick-Sheard PW, Marlin DJ, Thornhill R, Schroter RC. Frequency domain analysis of heart rate variability in horses at rest and during exercise.. Equine Vet J 2000 May;32(3):253-62.
- Cottin F, Médigue C, Lopes P, Petit E, Papelier Y, Billat VL. Effect of exercise intensity and repetition on heart rate variability during training in elite trotting horse.. Int J Sports Med 2005 Dec;26(10):859-67.
- Physick-Sheard PW, McGurrin MK. Ventricular arrhythmias during race recovery in Standardbred Racehorses and associations with autonomic activity.. J Vet Intern Med 2010 Sep-Oct;24(5):1158-66.
- Jose-Cunilleras E, Young LE, Newton JR, Marlin DJ. Cardiac arrhythmias during and after treadmill exercise in poorly performing thoroughbred racehorses.. Equine Vet J Suppl 2006 Aug;(36):163-70.
- Martin BB Jr, Reef VB, Parente EJ, Sage AD. Causes of poor performance of horses during training, racing, or showing: 348 cases (1992-1996).. J Am Vet Med Assoc 2000 Feb 15;216(4):554-8.
- Ryan N, Marr CM, McGladdery AJ. Survey of cardiac arrhythmias during submaximal and maximal exercise in Thoroughbred racehorses.. Equine Vet J 2005 May;37(3):265-8.
- Cottin F, Barrey E, Lopes P, Billat V. Effect of repeated exercise and recovery on heart rate variability in elite trotting horses during high intensity interval training.. Equine Vet J Suppl 2006 Aug;(36):204-9.
- Younes M, Robert C, Barrey E, Cottin F. Effects of Age, Exercise Duration, and Test Conditions on Heart Rate Variability in Young Endurance Horses.. Front Physiol 2016;7:155.
- Schwarzwald CC, Schober KE, Bonagura JD. Methods and reliability of tissue Doppler imaging for assessment of left ventricular radial wall motion in horses.. J Vet Intern Med 2009 May-Jun;23(3):643-52.
- Schwarzwald CC, Schober KE, Bonagura JD. Methods and reliability of echocardiographic assessment of left atrial size and mechanical function in horses.. Am J Vet Res 2007 Jul;68(7):735-47.
- Schefer KD, Bitschnau C, Weishaupt MA, Schwarzwald CC. Quantitative analysis of stress echocardiograms in healthy horses with 2-dimensional (2D) echocardiography, anatomical M-mode, tissue Doppler imaging, and 2D speckle tracking.. J Vet Intern Med 2010 Jul-Aug;24(4):918-31.
- Trachsel DS, Schwarzwald CC, Bitschnau C, Grenacher B, Weishaupt MA. Atrial natriuretic peptide and cardiac troponin I concentrations in healthy Warmblood horses and in Warmblood horses with mitral regurgitation at rest and after exercise.. J Vet Cardiol 2013 Jun;15(2):105-21.
- Young LE, van Loon G. Diseases of the heart and vessels. In: Hinchcliff KW, Kaneps AJ, Geor RJ, eds Equine Sports Medicine and Surgery, 2nd Ed. St Louis: Saunders Elsevier; 2014:695–743.
- Bitschnau C, Wiestner T, Trachsel DS, Auer JA, Weishaupt MA. Performance parameters and post exercise heart rate recovery in Warmblood sports horses of different performance levels.. Equine Vet J Suppl 2010 Nov;(38):17-22.
- Ciccone AB, Siedlik JA, Wecht JM, Deckert JA, Nguyen ND, Weir JP. Reminder: RMSSD and SD1 are identical heart rate variability metrics.. Muscle Nerve 2017 Oct;56(4):674-678.
- Bowen IM. Ambulatory electrocardiography and heart rate variability. In: Marr CM, Bowen M, eds. Cardiology of the Horse. 2nd ed. Edinburgh: Saunders Elsevier; 2010:127‐137.
- Broux B, De Clercq D, Decloedt A, Ven S, Vera L, van Steenkiste G, Mitchell K, Schwarzwald C, van Loon G. Heart rate variability parameters in horses distinguish atrial fibrillation from sinus rhythm before and after successful electrical cardioversion.. Equine Vet J 2017 Nov;49(6):723-728.
- Padilla DJ, McDonough P, Kindig CA, Erickson HH, Poole DC. Ventilatory dynamics and control of blood gases after maximal exercise in the Thoroughbred horse.. J Appl Physiol (1985) 2004 Jun;96(6):2187-93.
- Snow DH, Harris RC, MacDonald IA, Forster CD, Marlin DJ. Effects of high-intensity exercise on plasma catecholamines in the thoroughbred horse.. Equine Vet J 1992 Nov;24(6):462-7.
- Breuer HW, Skyschally A, Schulz R, Martin C, Wehr M, Heusch G. Heart rate variability and circulating catecholamine concentrations during steady state exercise in healthy volunteers.. Br Heart J 1993 Aug;70(2):144-9.
Citations
This article has been cited 11 times.- McCrae P, Spong H, Golestani N, Mahnam A, Bashura Y, Pearson W. Validation of an Equine Smart Textile System for Heart Rate Variability: A Preliminary Study. Animals (Basel) 2023 Feb 1;13(3).
- De Santis M, Seganfreddo S, Greco A, Normando S, Benedetti D, Mutinelli F, Contalbrigo L. Donkey Heart Rate and Heart Rate Variability: A Scoping Review. Animals (Basel) 2023 Jan 25;13(3).
- Wundersitz DWT, Wright BJ, Gordon BA, Pompei S, Lavie CJ, Nadurata V, Nolan K, Kingsley MIC. Sympathovagal Balance Is a Strong Predictor of Post High-Volume Endurance Exercise Cardiac Arrhythmia. Front Physiol 2022;13:848174.
- Kjeldsen ST, Nissen SD, Buhl R, Hopster-Iversen C. Paroxysmal Atrial Fibrillation in Horses: Pathophysiology, Diagnostics and Clinical Aspects. Animals (Basel) 2022 Mar 10;12(6).
- Chueainta P, Punyapornwithaya V, Tangjitjaroen W, Pongkan W, Boonyapakorn C. Acupuncture Improves Heart Rate Variability, Oxidative Stress Level, Exercise Tolerance, and Quality of Life in Tracheal Collapse Dogs. Vet Sci 2022 Feb 18;9(2).
- Ter Woort F, Dubois G, Tansley G, Didier M, Verdegaal L, Franklin S, Van Erck-Westergren E. Validation of an equine fitness tracker: ECG quality and arrhythmia detection. Equine Vet J 2022 Feb 9;55(2):336-43.
- Nyerges-Bohák Z, Nagy K, Rózsa L, Póti P, Kovács L. Heart rate variability before and after 14 weeks of training in Thoroughbred horses and Standardbred trotters with different training experience. PLoS One 2021;16(12):e0259933.
- Szabó C, Vizesi Z, Vincze A. Heart Rate and Heart Rate Variability of Amateur Show Jumping Horses Competing on Different Levels. Animals (Basel) 2021 Mar 4;11(3).
- Gehlen H, Loschelder J, Merle R, Walther M. Evaluation of Stress Response under a Standard Euthanasia Protocol in Horses Using Analysis of Heart Rate Variability. Animals (Basel) 2020 Mar 13;10(3).
- Navas de Solis C, Ramseyer A, Stefanovski D, Haughan J, Solomon CJ, Kirsch K. Association of heart rate variability, exercise intensity and exercising arrhythmias with competition results in eventing horses. Equine Vet J 2025 Nov;57(6):1446-1456.
- Pontaema T, Pongthaisong P, Kenchaiwong W, Chompoosan C, Lerdweeraphon W. Evaluation of vasovagal tonus index and electrocardiographic parameters in horses using a new modified base apex lead method. Vet World 2024 Jun;17(6):1385-1390.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists