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Home / Equine Research Bank / Animals (Basel) / Paroxysmal Atrial Fibrillation in Horses: Pathophysiology, D...
Animals : an open access journal from MDPI2022; 12(6); doi: 10.3390/ani12060698

Paroxysmal Atrial Fibrillation in Horses: Pathophysiology, Diagnostics and Clinical Aspects.

Abstract: Atrial fibrillation (AF) is the most common arrhythmia in horses causing poor performance. As in humans, the condition can be intermittent in nature, known as paroxysmal atrial fibrillation (pAF). This review covers the literature relating to pAF in horses and includes references to the human literature to compare pathophysiology, clinical presentation, diagnostic tools and treatment. The arrhythmia is diagnosed by auscultation and electrocardiography (ECG), and clinical signs can vary from sudden loss of racing performance to reduced fitness or no signs at all. If left untreated, pAF may promote electrical, functional and structural remodeling of the myocardium, thus creating a substrate that is able to maintain the arrhythmia, which over time may progress into permanent AF. Long-term ECG monitoring is essential for diagnosing the condition and fully understanding the duration and frequency of pAF episodes. The potential to adapt human cardiac monitoring systems and computational ECG analysis is therefore of interest and may benefit future diagnostic tools in equine medicine.
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Publication Date: 2022-03-10 PubMed ID: 35327097PubMed Central: PMC8944606DOI: 10.3390/ani12060698Google Scholar: Lookup
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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.

This research article focuses on the occurrence and treatment of paroxysmal atrial fibrillation (pAF) in horses, a condition characterized by intermittent and abnormal heart rhythm. The review makes use of existing literature on the topic, along with comparisons from human literature, to examine the pathophysiology, clinical presentation, diagnostic tools, and treatment of this condition.

Pathophysiology and Clinical Presentation

  • The article starts by defining atrial fibrillation (AF) as a prevalent arrhythmia in horses, which can lead to diminished physical performance. The intermittent manifestation of this condition is referred to as paroxysmal atrial fibrillation (pAF).
  • The clinical signs of pAF can be diverse, from sudden deterioration of racing performance to reduced fitness, or even showing no symptoms at all. Some horses may not show any signs, which makes this condition challenging to diagnose.
  • When pAF isn’t treated, it may cause electrical, functional, and structural changes in the myocardium (heart muscle). The changes in the heart muscle create an environment conducive for maintaining the arrhythmia, potentially progressing into persistent AF over time.

Diagnostic Tools and Treatment

  • The diagnosis of pAF involves auscultation (listening to the sounds within the body, especially heart sounds) and electrocardiography (ECG), which records the electrical activity of the heart over a period to detect abnormalities.
  • For a complete understanding of the duration and frequency of pAF episodes, long-term ECG monitoring is crucial. This is because pAF episodes could be brief and sporadic, making it difficult to capture in routine checks.
  • The review also considers the potential of adopting human cardiac monitoring systems and computational ECG analysis into equine medicine. These advanced tools could provide a more accurate and efficient way of diagnosing and managing the condition in horses.

The article advocates for an expanded utilization of these diagnostic tools and further research into potential treatment strategies for pAF in horses. The comparison to human literature serves to highlight possible advancements and adaptations that could benefit equine medicine, such as enhanced cardiac monitoring systems.

Cite This Article

APA
Kjeldsen ST, Nissen SD, Buhl R, Hopster-Iversen C. (2022). Paroxysmal Atrial Fibrillation in Horses: Pathophysiology, Diagnostics and Clinical Aspects. Animals (Basel), 12(6). https://doi.org/10.3390/ani12060698

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 12
Issue: 6

Researcher Affiliations

Kjeldsen, Sofie Troest
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Agrovej 8, DK-2630 Taastrup, Denmark.
Nissen, Sarah Dalgas
  • Laboratory of Cardiac Physiology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark.
Buhl, Rikke
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Agrovej 8, DK-2630 Taastrup, Denmark.
Hopster-Iversen, Charlotte
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Agrovej 8, DK-2630 Taastrup, Denmark.

Conflict of Interest Statement

The authors declare no conflict of interest.

References

This article includes 119 references
  1. Van Loon G. Cardiac Arrhythmias in Horses. Vet. Clin. North Am. Equine Pract. 2019;35:85–102.
    doi: 10.1016/j.cveq.2018.12.004pubmed: 30871832google scholar: lookup
  2. Ohmura H, Hiraga A, Takahashi T, Kai M, Jones JH. Risk factors for atrial fibrillation during racing in slow-finishing horses. J. Am. Vet. Med. Assoc. 2003;223:84–88.
    doi: 10.2460/javma.2003.223.84pubmed: 12839069google scholar: lookup
  3. Nath LC, Elliott AD, Weir J, Rosanowski SM, Franklin S, Curl P. Incidence, recurrence, and outcome of postrace atrial fibrillation in Thoroughbred horses. J. Vet. Intern. Med. 2021:1–10.
    doi: 10.1111/jvim.16063pmc: PMC7995445pubmed: 33604980google scholar: lookup
  4. Slack J, Boston RC, Soma LR, Reef VB. Occurrence of cardiac arrhythmias in Standardbred racehorses. Equine Vet. J. 2015;47:398–404.
    doi: 10.1111/evj.12299pubmed: 24819401google scholar: lookup
  5. Else RW, Holmes JR. Pathological Changes in Atrial Fibrillation in the Horse. Equine Vet. J. 1971;3:56–64.
    doi: 10.1111/j.2042-3306.1971.tb04441.xpubmed: 5161359google scholar: lookup
  6. Leroux AA, Detilleux J, Sandersen CF, Borde L, Houben RMAC, Al Haidar A, Art T, Amory H. Prevalence and Risk Factors for Cardiac Diseases in a Hospital-Based Population of 3,434 Horses (1994-2011). J. Vet. Intern. Med. 2013;27:1563–1570.
    doi: 10.1111/jvim.12197pubmed: 24112454google scholar: lookup
  7. Amada A, Kurita H, Training R, Amada A, Kurita H, Training R. Five cases of paroxysmal atrial fibrillation in the racehorse. Exp. Rep Equine Heal. Lab. 1975;100:89–100.
    doi: 10.11535/jes1961.1975.89google scholar: lookup
  8. Holmes JR, Henigan M, Williams RB, Witherington DH. Paroxysmal atrial fibrillation in racehorses. Equine Vet. J. 1986;18:37–42.
    doi: 10.1111/j.2042-3306.1986.tb03533.xpubmed: 3948829google scholar: lookup
  9. Buhl R, Carstensen H, Hesselkilde EZ, Klein BZ, Hougaard KM, Ravn KB, Loft-Andersen AV, Fenner MF, Pipper C, Jespersen T. Effect of induced chronic atrial fibrillation on exercise performance in Standardbred trotters. J. Vet. Intern. Med. 2018;32:1410–1419.
    doi: 10.1111/jvim.15137pmc: PMC6060327pubmed: 29749082google scholar: lookup
  10. Hesselkilde EZ, Carstensen H, Flethøj M, Fenner M, Kruse DD, Sattler SM, Tfelt-Hansen J, Pehrson S, Braunstein TH, Carlson J. Longitudinal study of electrical, functional and structural remodelling in an equine model of atrial fibrillation. BMC Cardiovasc. Disord. 2019;19:1–12.
    doi: 10.1186/s12872-019-1210-4pmc: PMC6805623pubmed: 31638896google scholar: lookup
  11. Reef VB, Reimer JM, Spencer PA. Treatment of Atrial Fibrillation in Horses: New Perspectives. J. Vet. Intern. Med. 1995;9:57–67.
    doi: 10.1111/j.1939-1676.1995.tb03274.xpubmed: 7760311google scholar: lookup
  12. Buhl R, Nissen SD, Winther MLK, Poulsen SK, Hopster-Iversen C, Jespersen T, Sanders P, Carstensen H, Hesselkilde EM. Implantable Loop Recorders can detect paroxysmal atrial fibrillation in Standardbred racehorses with intermittent poor performance. Equine Vet. J. 2020:1–9.
    doi: 10.1111/evj.13372pmc: PMC8451893pubmed: 33113157google scholar: lookup
  13. Inui T, Kohno H, Kawasaki Y, Matsuura K, Ueda H, Tamura Y, Watanabe M, Inage Y, Yakita Y, Wakabayashi Y. Use of a Smart Watch for Early Detection of Paroxysmal Atrial Fibrillation: Validation Study. JMIR Cardio. 2020;4:e14857.
    doi: 10.2196/14857pmc: PMC7003123pubmed: 32012044google scholar: lookup
  14. Strik M, Ploux S, Ramirez FD, Abu-Alrub S, Jaîs P, Haïssaguerre M, Bordachar P. Smartwatch-based detection of cardiac arrhythmias: Beyond the differentiation between sinus rhythm and atrial fibrillation. Hear. Rhythm. 2021;18:1524–1532.
    doi: 10.1016/j.hrthm.2021.06.1176pubmed: 34147700google scholar: lookup
  15. Rose RJ, Davis PE. Paroxysmal Atrial Fibrillation In A Racehorse. Aust. Vet. J. 1977;53:545–549.
    doi: 10.1111/j.1751-0813.1977.tb07943.xpubmed: 612335google scholar: lookup
  16. Hanka J, Van Den Hoven R, Schwarz B. Paroxysmal atrial fibrillation and clinically reversible cor pulmonale in a horse with complicated recurrent airway obstruction. Tierarztl. Prax. Ausgabe G Grosstiere Nutztiere. 2015;43:109–114.
    doi: 10.15653/TPG-140075pubmed: 25799435google scholar: lookup
  17. Deem DA, Fregin GF. Atrial fibrillation in horses: A review of 106 clinical cases, with consideration of prevalence, clinical signs, and prognosis. J. Am. Vet. Med. Assoc. 1982;180:261–265.
    pubmed: 7056674
  18. Wyse DG, Van Gelder IC, Ellinor PT, Go AS, Kalman JM, Narayan SM, Nattel S, Schotten U, Rienstra M. Lone atrial fibrillation: Does it exist?. J. Am. Coll. Cardiol. 2014;63:1715–1723.
    doi: 10.1016/j.jacc.2014.01.023pmc: PMC4008692pubmed: 24530673google scholar: lookup
  19. Lévy S. Classification system of atrial fibrillation. Curr. Opin. Cardiol. 2000;15:54–57.
    doi: 10.1097/00001573-200001000-00007pubmed: 10666661google scholar: lookup
  20. Hindricks G, Potpara T, Dagres N. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS). Eur. Heart J. 2021;42:373–498.
    doi: 10.1093/eurheartj/ehaa612pubmed: 32860505google scholar: lookup
  21. January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JC, Conti JB, Ellinor PT, Ezekowitz MD, Field ME. 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation. Circulation. 2014;130:e199–e267.
    doi: 10.1161/CIR.0000000000000041pmc: PMC4676081pubmed: 24682347google scholar: lookup
  22. Levy S, Novella P, Ricard P, Paganelli F. Paroxysmal A trial Fibrillation: A Need for Classification. J. Cardiovasc. Electrophysiol. 1995;6:69–74.
    doi: 10.1111/j.1540-8167.1995.tb00758.xpubmed: 7743011google scholar: lookup
  23. McGurrin K, Kimberly M, McGurrin J. The diagnosis and management of atrial fibrillation in the horse. Vet. Med. Res. Rep. 2015;6:83–90.
    doi: 10.2147/vmrr.s46304pmc: PMC6067668pubmed: 30101098google scholar: lookup
  24. Reef VB, Bonagura J, Buhl R, Mcgurrin MKJ, Schwarzwald CC, van Loon G, Young LE. Recommendations for management of equine athletes with cardiovascular abnormalities. J. Vet. Intern. Med. 2014;28:749–761.
    doi: 10.1111/jvim.12340pmc: PMC4895474pubmed: 24628586google scholar: lookup
  25. Wijffels MCEF, Kirchhof CJHJ, Dorland R, Allessie MA. Atrial fibrillation begets atrial fibrillation: A study in awake chronically instrumented goats. Circulation. 1995;92:1954–1968.
    doi: 10.1161/01.CIR.92.7.1954pubmed: 7671380google scholar: lookup
  26. Clauss S, Bleyer C, Schüttler D, Tomsits P, Renner S, Klymiuk N, Wakili R, Massberg S, Wolf E, Kääb S. Animal models of arrhythmia: Classic electrophysiology to genetically modified large animals. Nat. Rev. Cardiol. 2019;16:457–475.
    doi: 10.1038/s41569-019-0179-0pubmed: 30894679google scholar: lookup
  27. Nattel S, Dobrev D. Electrophysiological and molecular mechanisms of paroxysmal atrial fibrillation. Nat. Rev. Cardiol. 2016;13:575–590.
    doi: 10.1038/nrcardio.2016.118pubmed: 27489190google scholar: lookup
  28. Decloedt A, Van Steenkiste G, Vera L, Buhl R, van Loon G. Atrial fibrillation in horses part 1: Pathophysiology. Vet. J. 2020;263:1–8.
    doi: 10.1016/j.tvjl.2020.105521pubmed: 32928494google scholar: lookup
  29. Allessie MA, Boyden PA, Camm AJ, Kléber AG, Lab MJ, Legato MJ, Rosen MR, Schwartz PJ, Spooner PM, Van Wagoner DR. Pathophysiology and Prevention of Atrial Fibrillation. Circulation. 2001;103:769–777.
    doi: 10.1161/01.CIR.103.5.769pubmed: 11156892google scholar: lookup
  30. Schotten U, Verheule S, Kirchhof P, Goette A. Pathophysiological mechanisms of atrial fibrillation: A translational appraisal. Physiol. Rev. 2011;91:265–325.
    doi: 10.1152/physrev.00031.2009pubmed: 21248168google scholar: lookup
  31. Wakili R, Voigt N, Kääb S, Dobrev D, Nattel S. Recent advances in the molecular pathophysiology of atrial fibrillation. J. Clin. Invest. 2011;121:2955–2968.
    doi: 10.1172/JCI46315pmc: PMC3148739pubmed: 21804195google scholar: lookup
  32. Hiraga A, Kubo K. Two cases of paroxysmal atrial fibrillation during exercise in horses. Equine Vet. Educ. 1999;11:6–10.
    doi: 10.1111/j.2042-3292.1999.tb00909.xgoogle scholar: lookup
  33. Jensen TJ, Haarbo J, Pehrson SM, Thomsen B. Impact of premature atrial contractions in atrial fibrillation. Pacing Clin. Electrophysiol. 2004;27:447–452.
    doi: 10.1111/j.1540-8159.2004.00462.xpubmed: 15078396google scholar: lookup
  34. Vandecasteele T, Van Den Broeck W, Tay H, Couck L, van Loon G, Cornillie P. 3D reconstruction of the porcine and equine pulmonary veins, supplemented with the identification of telocytes in the horse. J. Vet. Med. Ser. C Anat. Histol. Embryol. 2018;47:145–152.
    doi: 10.1111/ahe.12334pubmed: 29314148google scholar: lookup
  35. Chen SA, Hsieh MH, Tai CT, Tsai CF, Prakash VS, Yu WC, Hsu TL, Ding YA, Chang MS. Initiation of atrial fibrillation by ectopic beats originating from the pulmonary veins: Electrophysiological characteristics, pharmacological responses, and effects of radiofrequency ablation. Circulation. 1999;100:1879–1886.
    doi: 10.1161/01.CIR.100.18.1879pubmed: 10545432google scholar: lookup
  36. Haïssaguerre M, Jaïs P, Shah DC, Takahashi A, Hocini M, Quiniou G, Garrigue S, Le Mouroux A, Le Métayer P, Clémenty J. Spontaneous Initiation of Atrial Fibrillation by Ectopic Beats Originating in the Pulmonary Veins. N. Engl. J. Med. 1998;339:659–666.
    doi: 10.1056/NEJM199809033391003pubmed: 9725923google scholar: lookup
  37. Linz D, Hesselkilde E, Kutieleh R, Jespersen T, Buhl R, Sanders P. Pulmonary vein firing initiating atrial fibrillation in the horse: Oversized dimensions but similar mechanisms. J. Cardiovasc. Electrophysiol. 2020;31:1211–1212.
    doi: 10.1111/jce.14422pubmed: 32108401google scholar: lookup
  38. Voigt N, Heijman J, Wang Q, Chiang DY, Li N, Karck M, Wehrens XHT, Nattel S, Dobrev D. Cellular and molecular mechanisms of atrial arrhythmogenesis in patients with paroxysmal atrial fibrillation. Circulation. 2014;129:145–156.
    doi: 10.1161/CIRCULATIONAHA.113.006641pmc: PMC4342412pubmed: 24249718google scholar: lookup
  39. Yue L, Xie J, Nattel S. Molecular determinants of cardiac fibroblast electrical function and therapeutic implications for atrial fibrillation. Cardiovasc. Res. 2011;89:744–753.
    doi: 10.1093/cvr/cvq329pmc: PMC3039247pubmed: 20962103google scholar: lookup
  40. Rohr S. Myofibroblasts in diseased hearts: New players in cardiac arrhythmias?. Hear. Rhythm. 2009;6:848–856.
    doi: 10.1016/j.hrthm.2009.02.038pubmed: 19467515google scholar: lookup
  41. Saljic A, Friederike Fenner M, Winters J, Flethøj M, Eggert Eggertsen C, Carstensen H, Dalgas Nissen S, Melis Hesselkilde E, van Hunnik A, Schotten U. Increased fibroblast accumulation in the equine heart following persistent atrial fibrillation. IJC Hear. Vasc. 2021;35:100842.
    doi: 10.1016/j.ijcha.2021.100842pmc: PMC8322305pubmed: 34355058google scholar: lookup
  42. Lau DH, Linz D, Schotten U, Mahajan R, Sanders P, Kalman JM. Pathophysiology of Paroxysmal and Persistent Atrial Fibrillation: Rotors, Foci and Fibrosis. Hear. Lung Circ. 2017;26:887–893.
    doi: 10.1016/j.hlc.2017.05.119pubmed: 28610723google scholar: lookup
  43. Hesselkilde EZ, Carstensen H, Haugaard MM, Carlson J, Pehrson S, Jespersen T, Buhl R, Platonov PG. Effect of flecainide on atrial fibrillatory rate in a large animal model with induced atrial fibrillation. BMC Cardiovasc. Disord. 2017;17:4–9.
    doi: 10.1186/s12872-017-0720-1pmc: PMC5723027pubmed: 29221440google scholar: lookup
  44. Choudhary MB, Holmqvist F, Carlson J, Nilsson HJ, Roijer A, Platonov PG. Low atrial fibrillatory rate is associated with spontaneous conversion of recent-onset atrial fibrillation. Europace. 2013;15:1445–1452.
    doi: 10.1093/europace/eut057pubmed: 23515337google scholar: lookup
  45. Decloedt A, de Clercq D, van der Vekens N, Verheyen T, van Loon G. Noninvasive determination of atrial fibrillation cycle length by atrial colour tissue Doppler imaging in horses. Equine Vet. J. 2014;46:174–179.
    doi: 10.1111/evj.12108pubmed: 23738919google scholar: lookup
  46. De Clercq D, Van Loon G, Tavernier R, Duchateau L, Deprez P, De Clercq D, Van Loon G, Tavernier R, Duchateau L, Deprez P. Atrial and ventricular electrical and contractile remodeling and reverse remodeling owing to short-term pacing-induced atrial fibrillation in horses. J. Vet. Intern. Med. 2008;22:1353–1359.
    doi: 10.1111/j.1939-1676.2008.0202.xpubmed: 19000247google scholar: lookup
  47. Schotten U, Duytschaever M, Ausma J, Eijsbouts S, Neuberger HR, Allessie M. Electrical and contractile remodeling during the first days of atrial fibrillation go hand in hand. Circulation. 2003;107:1433–1439.
    doi: 10.1161/01.CIR.0000055314.10801.4Fpubmed: 12642366google scholar: lookup
  48. Allessie M, Ausma J, Schotten U. Electrical, contractile and structural remodeling during atrial fibrillation. Cardiovasc. Res. 2002;54:230–246.
    doi: 10.1016/S0008-6363(02)00258-4pubmed: 12062329google scholar: lookup
  49. Decloedt A, Verheyen T, Van Der Vekens N, Sys S, De Clercq D, Van Loon G. Long-term follow-up of atrial function after cardioversion of atrial fibrillation in horses. Vet. J. 2013;197:583–588.
    doi: 10.1016/j.tvjl.2013.05.032pubmed: 23823082google scholar: lookup
  50. Schwarzwald CC, Schober KE, Bonagura JD. Echocardiographic evidence of left atrial mechanical dysfunction after conversion of atrial fibrillation to sinus rhythm in 5 horses. J. Vet. Intern. Med. 2007;21:820–827.
    doi: 10.1111/j.1939-1676.2007.tb03027.xpubmed: 17708405google scholar: lookup
  51. Amada A, Senta T, Kubo K, Oh-ishi S, Kiryyu K. Atrial Fibrillation Histopathological in the Horse: Clinical Histopathological Studies of Two Cases. I. Clin. Study. I. Clin. Study. 1974;69:51–69.
  52. Kiryu K, Amada A, Kaneko K, Hiroshi S. Atrial fibrillation in the horse: Clinical and histopathological studies of two cases, II: Formal pathogenesis. Exp. Reports Equine Health Lab. 1974:70–86.
    doi: 10.11535/jes1961.1974.70google scholar: lookup
  53. Cao H, Xue L, Wu Y, Ma H, Chen L, Wang X, Zhu Q, Dai N, Chen Y. Natriuretic peptides and right atrial fibrosis in patients with paroxysmal versus persistent atrial fibrillation. Peptides. 2010;31:1531–1539.
    doi: 10.1016/j.peptides.2010.04.019pubmed: 20434499google scholar: lookup
  54. Goette A, Arndt M, Röcken C, Spiess A, Staack T, Geller JC, Huth C, Ansorge S, Klein HU, Lendeckel U. Regulation of angiotensin II receptor subtypes during atrial fibrillation in humans. Circulation. 2000;101:2678–2781.
    doi: 10.1161/01.CIR.101.23.2678pubmed: 10851203google scholar: lookup
  55. Xiao H, Lei H, Qin S, Ma K, Wang X. TGF-β1 Expression and Atrial Myocardium Fibrosis Increase in Atrial Fibrillation Secondary to Rheumatic Heart Disease. Clin. Cardiol. 2010;33:139–156.
    doi: 10.1002/clc.20713pmc: PMC6652867pubmed: 20235205google scholar: lookup
  56. Zhao F, Zhang S, Shao Y, Wu Y, Qin J, Chen Y, Chen L, Gu H, Wang X, Huang C. Calreticulin overexpression correlates with integrin-α5 and transforming growth factor-β1 expression in the atria of patients with rheumatic valvular disease and atrial fibrillation. Int. J. Cardiol. 2013;168:2177–2185.
    doi: 10.1016/j.ijcard.2013.01.239pubmed: 23465222google scholar: lookup
  57. Platonov PG, Mitrofanova LB, Orshanskaya V, Ho SY. Structural abnormalities in atrial walls are associated with presence and persistency of atrial fibrillation but not with age. J. Am. Coll. Cardiol. 2011;58:2225–2232.
    doi: 10.1016/j.jacc.2011.05.061pubmed: 22078429google scholar: lookup
  58. Brooijmans AW. Electrocardiogaphying Horses and Cattle: Theoretical and Clinical Aspects. Utrecht State University; Ultrecht, The Netherlands: 1957.
  59. Detweiler DK. Proceedings of the American Veterinary Medical Association. AVMA; Atlantic City, NJ, USA: 1952.
  60. Glazier DB, Kavanagh JF. An unusual case of atrial fibrillation in a racing thoroughbred filly. Ir. Vet. J. 1967;21:107–110.
  61. Reef VB, Levitan CW, Spencer PA. Factors Affecting Prognosis and Conversion in Equine Atrial Fibrillation. J. Vet. Intern. Med. 1988;2:1–6.
    doi: 10.1111/j.1939-1676.1988.tb01970.xpubmed: 3221350google scholar: lookup
  62. Holmes JR. Cardiac arrhythmias on the racecourse. Equine Exerc. Physiol. 1987;2:781–785.
  63. Machida N, Yasuda J, Too K. Three cases of paroxysmal atrial fibrillation in the Thoroughbred newborn foal. Equine Vet. J. 1989;21:66–68.
    doi: 10.1111/j.2042-3306.1989.tb02091.xpubmed: 2920703google scholar: lookup
  64. Physick-Sheard P, Kraus M, Basrur P, Mcgurrin K, Kenney D, Schenkel F. Breed predisposition and heritability of atrial fibrillation in the Standardbred horse: A retrospective caseecontrol study. J. Vet. Cardiol. 2014;16:173–184.
    doi: 10.1016/j.jvc.2014.03.006pubmed: 25087649google scholar: lookup
  65. Kraus M, Physick-Sheard PW, Brito LF, Schenkel FS. Estimates of heritability of atrial fibrillation in the Standardbred racehorse. Equine Vet. J. 2017;49:718–722.
    doi: 10.1111/evj.12687pubmed: 28391631google scholar: lookup
  66. Kraus M, Physick-Sheard P, Brito LF, Sargolzaei M, Schenkel FS. Marginal ancestral contributions to atrial fibrillation in the standardbred racehorse: Comparison of cases and controls. PLoS ONE. 2018;13:e0197137.
    doi: 10.1371/journal.pone.0197137pmc: PMC5953485pubmed: 29763439google scholar: lookup
  67. Pedler C, Nath L, Agne GF, Hebart M, Franklin S. Heritability estimates of atrial fibrillation in Thoroughbred racehorses in Hong Kong and Australia. J. Vet. Cardiol. 2021;36:115–122.
    doi: 10.1016/j.jvc.2021.05.008pubmed: 34218164google scholar: lookup
  68. Frontera A, Carpenter A, Ahmed N, Fasiolo M, Nelson M, Diab I, Cripps T, Thomas G, Duncan E. Demographic and clinical characteristics to predict paroxysmal atrial fibrillation: Insights from an implantable loop recorder population. PACE - Pacing Clin. Electrophysiol. 2015;38:1217–1222.
    doi: 10.1111/pace.12692pubmed: 26183170google scholar: lookup
  69. Laredo M, Waldmann V, Khairy P, Nattel S. Age as a Critical Determinant of Atrial Fibrillation: A Two-sided Relationship. Can. J. Cardiol. 2018;34:1396–1406.
    doi: 10.1016/j.cjca.2018.08.007pubmed: 30404745google scholar: lookup
  70. de Vos CB, Pisters R, Nieuwlaat R, Prins MH, Tieleman RG, Coelen RJS, van den Heijkant AC, Allessie MA, Crijns HJGM, Andresen D. Progression From Paroxysmal to Persistent Atrial Fibrillation. Clinical Correlates and Prognosis. J. Am. Coll. Cardiol. 2010;55:725–731.
    doi: 10.1016/j.jacc.2009.11.040pubmed: 20170808google scholar: lookup
  71. Machida N, Kiryu K. Cardiac Lesions in Dairy Cows with Idiopathic Atrial Fibrillation. J. Vet. Med. Sci. 2001;63:873–878.
    doi: 10.1292/jvms.63.873pubmed: 11558542google scholar: lookup
  72. Menaut P, Bélanger MC, Beauchamp G, Ponzio NM, Moïse NS. Atrial fibrillation in dogs with and without structural or functional cardiac disease: A retrospective study of 109 cases. J. Vet. Cardiol. 2005;7:75–83.
    doi: 10.1016/j.jvc.2005.07.002pubmed: 19083323google scholar: lookup
  73. Saljic A, Jespersen T, Buhl R. Antiarrhythmic investigations in large animal models of atrial fibrillation. Br. J. Pharmacol. 2021:1–21.
    doi: 10.1111/bph.15417pubmed: 33624840google scholar: lookup
  74. Kaese S, Verheule S. Cardiac electrophysiology in mice: A matter of size. Front. Physiol. 2012;3:1–19.
    doi: 10.3389/fphys.2012.00345pmc: PMC3433738pubmed: 22973235google scholar: lookup
  75. Kirchhof P, Lip GYH, van Gelder IC, Bax J, Hylek E, Kääb S, Schotten U, Wegscheider K, Boriani G, Ezekowitz M. Comprehensive risk reduction in patients with atrial fibrillation: Emerging diagnostic and therapeutic options. Thromb. Haemost. 2011;106:1012–1019.
    doi: 10.1160/TH11-07-0517pubmed: 22048744google scholar: lookup
  76. Parkash R, Green MS, Kerr CR, Connolly SJ, Klein GJ, Sheldon R, Talajic M, Dorian P, Humphries KH. The association of left atrial size and occurrence of atrial fibrillation: A prospective cohort study from the Canadian Registry of Atrial Fibrillation. Am. Heart J. 2004;148:649–654.
    doi: 10.1016/j.ahj.2004.04.029pubmed: 15459596google scholar: lookup
  77. Van Loon G, Tavernier R, Duytschaever M, Fonteyne W, Deprez P, Jordaens L. Pacing induced sustained atrial fibrillation in a pony. Can. J. Vet. Res. 2000;64:254–258.
    pmc: PMC1189629pubmed: 11041507
  78. Van Loon G, Duytschaever M, Tavernier R, Fonteyne W, Jordaens L, Deprez P. An equine model of chronic atrial fibrillation: Methodology. Vet. J. 2002;164:142–150.
    doi: 10.1053/tvjl.2001.0668pubmed: 12359469google scholar: lookup
  79. Decloedt A, Schwarzwald CC, De Clercq D, Van Der Vekens N, Pardon B, Reef VB, van Loon G. Risk Factors for Recurrence of Atrial Fibrillation in Horses After Cardioversion to Sinus Rhythm. J. Vet. Intern. Med. 2015;29:946–953.
    doi: 10.1111/jvim.12606pmc: PMC4895430pubmed: 25917409google scholar: lookup
  80. Chen PS, Chen LS, Fishbein MC, Lin SF, Nattel S. Role of the autonomic nervous system in atrial fibrillation: Pathophysiology and therapy. Circ. Res. 2014;114:1500–1515.
    doi: 10.1161/CIRCRESAHA.114.303772pmc: PMC4043633pubmed: 24763467google scholar: lookup
  81. Linz D, Elliott AD, Hohl M, Malik V, Schotten U, Dobrev D, Nattel S, Böhm M, Floras J, Lau DH. Role of autonomic nervous system in atrial fibrillation. Int. J. Cardiol. 2019;287:181–188.
    doi: 10.1016/j.ijcard.2018.11.091pubmed: 30497894google scholar: lookup
  82. Tan AY, Zhou S, Ogawa M, Song J, Chu M, Li H, Fishbein MC, Lin SF, Chen LS, Chen PS. Neural mechanisms of paroxysmal atrial fibrillation and paroxysmal atrial tachycardia in ambulatory canines. Circulation. 2008;118:916–925.
    doi: 10.1161/CIRCULATIONAHA.108.776203pmc: PMC2742977pubmed: 18697820google scholar: lookup
  83. Yamashita T, Murakawa Y, Sezaki K, Inoue M, Hayami N, Shuzui Y, Omata M. Circadian Variation of Paroxysmal Atrial Fibrillation. Circulation. 1997;96:1537–1541.
    doi: 10.1161/01.CIR.96.5.1537pubmed: 9315544google scholar: lookup
  84. Viskin S, Golovner M, Malov N, Fish R, Alroy I, Vila Y, Laniado S, Kaplinsky E, Roth A. Circadian variation of symptomatic paroxysmal atrial fibrillation; Data from almost 10,000 episodes. Eur. Heart J. 1999;20:1429–1434.
    doi: 10.1053/euhj.1999.1632pubmed: 10487804google scholar: lookup
  85. Frick L, Schwarzwald CC, Mitchell KJ. The use of heart rate variability analysis to detect arrhythmias in horses undergoing a standard treadmill exercise test. J. Vet. Intern. Med. 2019;33:212–224.
    doi: 10.1111/jvim.15358pmc: PMC6335521pubmed: 30520119google scholar: lookup
  86. Buhl R, Petersen EE, Lindholm M, Bak L, Nostell K. Cardiac arrhythmias in standardbreds during and after racing-possible association between heart size, valvular regurgitations, and arrhythmias. J. Equine Vet. Sci. 2013;33:590–596.
    doi: 10.1016/j.jevs.2012.09.009google scholar: lookup
  87. Carstensen H, Hesselkilde EZ, Fenner M, Loft-Andersen AV, Flethøj M, Kanters JK, Sattler SM, Tfelt-Hansen J, Pehrson S, Jespersen T. Time-dependent antiarrhythmic effects of flecainide on induced atrial fibrillation in horses. J. Vet. Intern. Med. 2018;32:1708–1717.
    doi: 10.1111/jvim.15287pmc: PMC6189357pubmed: 30133839google scholar: lookup
  88. Gelzer ARM, Moïse NS, Vaidya D, Wagner KA, Jalife J. Temporal organization of atrial activity and irregular ventricular rhythm during spontaneous atrial fibrillation: An in vivo study in the horse. J. Cardiovasc. Electrophysiol. 2000;11:773–784.
    doi: 10.1111/j.1540-8167.2000.tb00049.xpubmed: 10921795google scholar: lookup
  89. Gelberg HB, Smetzer DL, Foreman JH. Pulmonary hypertension as a cause of atrial fibrillation in young horses: Four cases (1980-1989). J. Am. Vet. Med. Assoc. 1991;198:679–682.
    pubmed: 2019543
  90. Chen LY, Chung MK, Allen LA, Ezekowitz M, Furie KL, McCabe P, Noseworthy PA, Perez MV, Turakhia MP. Atrial Fibrillation Burden: Moving Beyond Atrial Fibrillation as a Binary Entity: A Scientific Statement From the American Heart Association. Circulation. 2018;137:e623–e644.
    doi: 10.1161/CIR.0000000000000568pmc: PMC8463258pubmed: 29661944google scholar: lookup
  91. Buhl R, Hesselkilde EM, Carstensen H, Fenner MF, Jespersen T, Tfelt-Hansen J, Michael Sattler S. Detection of atrial fibrillation with implantable loop recorders in horses. Equine Vet. J. 2021;53:397–403.
    doi: 10.1111/evj.13301pmc: PMC7891449pubmed: 32506470google scholar: lookup
  92. Raekallio M. Long Term ECG Recording with Holter Monitoring in Clinically Healthy Horses. Acta Vet. Scand. 1992;33:71–75.
    doi: 10.1186/BF03546937pmc: PMC8117866pubmed: 1598859google scholar: lookup
  93. 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;19:160–174.
    doi: 10.1016/j.jvc.2016.10.006pubmed: 28117225google scholar: lookup
  94. 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;49:723–728.
    doi: 10.1111/evj.12684pubmed: 28323361google scholar: lookup
  95. Keen JA, O’Connor SA. Evaluation of a novel ambulatory electrocardiogram monitor (the Carnation Ambulatory Monitor) for use in horses. J. Vet. Cardiol. 2021;34:16–28.
    doi: 10.1016/j.jvc.2020.12.005pubmed: 33548735google scholar: lookup
  96. Parker M, Goodwin D, Eager RA, Redhead ES, Marlin DJ. Comparison of Polar® heart rate interval data with simultaneously recorded ECG signals in horses. Comp. Exerc. Physiol. 2009;6:137–142.
    doi: 10.1017/S1755254010000024google scholar: lookup
  97. Ille N, Aurich J, 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. Clin. Appl. Res. 2014;9:341–346.
    doi: 10.1016/j.jveb.2014.07.006google scholar: lookup
  98. ter Woort F, Dubois G, Didier M, Van Erck-Westergren E. Validation of an equine fitness tracker: Heart rate and heart rate variability. Comp. Exerc. Physiol. 2021;17:189–198.
    doi: 10.3920/CEP200028google scholar: lookup
  99. Lenoir A, Trachsel DS, Younes M, Barrey E, Robert C. Agreement between electrocardiogram and heart rate meter is low for the measurement of heart rate variability during exercise in young endurance horses. Front. Vet. Sci. 2017;4:170.
    doi: 10.3389/fvets.2017.00170pmc: PMC5650972pubmed: 29090214google scholar: lookup
  100. Nath LC, Forbes G, Elliott AD, Tomren V, Ryan A, Franklin SH. Application of an electrocardiography device (iECG) for heart rhythm analysis after exercise in Thoroughbred horses. Aust. Vet. J. 2021:1–7.
    doi: 10.1111/avj.13137pubmed: 34859419google scholar: lookup
  101. Broux B, De Clercq D, Vera L, Ven S, Deprez P, Decloedt A, Van Loon G. Can heart rate variability parameters derived by a heart rate monitor differentiate between atrial fibrillation and sinus rhythm?. BMC Vet. Res. 2018;14:1–7.
    doi: 10.1186/s12917-018-1650-6pmc: PMC6203204pubmed: 30359273google scholar: lookup
  102. Eerikäinen LM, Bonomi AG, Dekker LRC, Vullings R, Aarts RM. Atrial fibrillation monitoring with wrist-worn photoplethysmography-based wearables: State-of-the-art review. Cardiovasc. Digit. Heal. J. 2020;1:45–51.
    doi: 10.1016/j.cvdhj.2020.03.001pmc: PMC8890076pubmed: 35265873google scholar: lookup
  103. Rosman L, Gehi A, Lampert R. When smartwatches contribute to health anxiety in patients with atrial fibrillation. Cardiovasc. Digit. Health J. 2020;1:9–10.
    doi: 10.1016/j.cvdhj.2020.06.004pmc: PMC8357265pubmed: 34386784google scholar: lookup
  104. Nelson BW, Low CA, Jacobson N, Areán P, Torous J, Allen NB. Guidelines for wrist-worn consumer wearable assessment of heart rate in biobehavioral research. npj Digit. Med. 2020;3:1–9.
    doi: 10.1038/s41746-020-0297-4pmc: PMC7320189pubmed: 32613085google scholar: lookup
  105. Alexeenko V, Fraser JA, Bowen M, Huang CLH, Marr CM, Jeevaratnam K. The complexity of clinically-normal sinus-rhythm ECGs is decreased in equine athletes with a diagnosis of paroxysmal atrial fibrillation. Sci. Rep. 2020;10:1–10.
    doi: 10.1038/s41598-020-63343-7pmc: PMC7176685pubmed: 32321950google scholar: lookup
  106. Huang YH, Alexeenko V, Tse G, Huang CL-H, Marr CM, Jeevaratnam K. ECG Restitution Analysis and Machine Learning to Detect Paroxysmal Atrial Fibrillation: Insight from the Equine Athlete as a Model for Human Athletes. Function. 2020;2:1–10.
    doi: 10.1093/function/zqaa031pmc: PMC8788737pubmed: 35330977google scholar: lookup
  107. Andrade J, Khairy P, Dobrev D, Nattel S. The clinical profile and pathophysiology of atrial fibrillation: Relationships among clinical features, epidemiology, and mechanisms. Circ. Res. 2014;114:1453–1468.
    doi: 10.1161/CIRCRESAHA.114.303211pubmed: 24763464google scholar: lookup
  108. Lip GYH, Li Saw Hee FL. Paroxysmal atrial fibrillation. Mon. J. Assoc. Physicians. 2001;94:665–678.
    doi: 10.1093/qjmed/94.12.665pubmed: 11744787google scholar: lookup
  109. Negreva M, Prodanova K, Vitlianova K, Madjova C. Paroxysmal atrial fibrillation: Changes in factor VIII and von Willebrand factor impose early hypercoagulability. Arch. Med. Sci. - Atheroscler. Dis. 2020;5:140–147.
    doi: 10.5114/amsad.2020.97101pmc: PMC7433786pubmed: 32832713google scholar: lookup
  110. Navas de Solís CN, Reef VB, Slack JA, Jose-Cunilleras E. Evaluation of coagulation and fibrinolysis in horses with atrial fibrillation. J. Am. Vet. Med. Assoc. 2016;248:201–206.
    doi: 10.2460/javma.248.2.201pubmed: 26720087google scholar: lookup
  111. Lip GYH, Nieuwlaat R, Pisters R, Lane DA, Crijns HJGM. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: The Euro Heart Survey on atrial fibrillation. Chest. 2010;137:263–272.
    doi: 10.1378/chest.09-1584pubmed: 19762550google scholar: lookup
  112. Gage BF, Waterman AD, Shannon W, Boechler M, Rich MW, Radford MJ. Validation of clinical classification schemes for predicting stroke: Results from the National Registry of Atrial Fibrillation. J. Am. Med. Assoc. 2001;285:2864–2870.
    doi: 10.1001/jama.285.22.2864pubmed: 11401607google scholar: lookup
  113. Hesselkilde E, Linz D, Saljic A, Carstensen H, Kutieleh R, Jespersen T, Sanders P, Buhl R. First catheter-based high-density endocardial 3D electroanatomical mapping of the right atrium in standing horses. Equine Vet. J. 2021;53:186–193.
    doi: 10.1111/evj.13265pmc: PMC7818172pubmed: 32285961google scholar: lookup
  114. Van Loon G, Van Steenkiste G, Vera L, Decloedt A. Catheter-based electrical interventions to study, diagnose and treat arrhythmias in horses: From refractory period to electro-anatomical mapping. Vet. J. 2020;263:105519.
    doi: 10.1016/j.tvjl.2020.105519pubmed: 32928488google scholar: lookup
  115. Van Steenkiste G, Duytschaever M, De Clercq D, Tavernier R, Vera L, Michielsen A, Decloedt A, Schauvliege S, van Loon G. First successful radiofrequency ablation of focal atrial tachycardia in a horse guided by a high density 3D electro-anatomical mapping system (Rhythmia®); Proceedings of the 11th European College of Equine Internal Medicine Congress; Ghent, Belgium. 7–10 November 2018; p. 97.
  116. Morillo CA, Verma A, Connolly SJ, Kuck KH, Nair GM, Champagne J, Sterns LD, Beresh H, Healey JS, Natale A. Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of paroxysmal atrial fibrillation (RAAFT-2) a randomized trial. JAMA - J. Am. Med. Assoc. 2014;311:692–699.
    doi: 10.1001/jama.2014.467pubmed: 24549549google scholar: lookup
  117. McGurrin MKJ, Physick-Sheard PW, Kenney DG. How to perform transvenous electrical cardioversion in horses with atrial fibrillation. J. Vet. Cardiol. 2005;7:109–119.
    doi: 10.1016/j.jvc.2005.09.001pubmed: 19083326google scholar: lookup
  118. Kimberly M, McGurrin J, Physick-Sheard PW, Kenney DG, Kerr C, Hanna WJB. Transvenous Electrical Cardioversion of Equine Atrial Fibrillation Technical Considerations. J. Vet. Intern. Med. 2005;19:695–702.
    doi: 10.1111/j.1939-1676.2005.tb02748.xpubmed: 16231714google scholar: lookup
  119. Buhl R, Hesselkilde EM, Carstensen H, Hopster-Iversen C, Loon G, Decloedt A, Van Steenkiste G, Marr CM, Reef VB, Schwarzwald CC. Atrial fibrillatory rate as predictor of recurrence of atrial fibrillation in horses treated medically or with electrical cardioversion. Equine Vet. J. 2022.
    doi: 10.1111/evj.13551pmc: PMC9787611pubmed: 34957586google scholar: lookup

Citations

This article has been cited 6 times.
  1. Natterson-Horowitz B, Wright K, Van Steenkiste G, Decloedt A, Gagnon AL, Cai X, Mazmanian A. Arrhythmias across the tree of life: comparative insights for human electrophysiology. Front Cardiovasc Med 2025;12:1652591.
    doi: 10.3389/fcvm.2025.1652591pubmed: 41567384google scholar: lookup
  2. Haugaard SL, Schneider MJ, Kjeldsen ST, Sattler SM, Bastrup JA, Saljic A, Birk JB, Hansen C, Synnestvedt JN, van Hunnik A, Sobota V, Carstensen H, Hopster-Iversen C, Schwarzwald CC, Altintaş A, Barrès R, Jepps TA, Larsen S, Kjøbsted R, Wojtaszewski JFP, Barrado Ballestero S, Roostalu U, Herum KM, Jespersen T, Nattel S, Nissen SD, Buhl R. Metformin Protects Against Persistent Atrial Fibrillation in an Equine Model. Circ Arrhythm Electrophysiol 2025 Dec;18(12):e013850.
    doi: 10.1161/CIRCEP.125.013850pubmed: 41328576google scholar: lookup
  3. Avison A, Physick-Sheard PW, Pyle WG. Performance horses as a model for exercise-associated cardiac arrhythmias and sudden cardiac death. J Mol Cell Cardiol Plus 2025 Jun;12:100452.
    doi: 10.1016/j.jmccpl.2025.100452pubmed: 40475708google scholar: lookup
  4. Kuroda T, Minamijima Y, Kinman CK, Takahashi Y, Ebisuda Y, Inoue K, Ishikawa H, Mita H, Tamura N, Nukada T, Toutain PL, Ohta M. Rational quinidine dosage regimen for atrial fibrillation in Thoroughbred racehorses based on population pharmacokinetics. Front Vet Sci 2024;11:1454342.
    doi: 10.3389/fvets.2024.1454342pubmed: 39439824google scholar: lookup
  5. Kjeldsen ST, Nissen SD, Christensen NC, Haugaard SL, Schneider MJ, Vinther Z, Sattler SM, Carstensen H, Jøns C, Hopster-Iversen C, Buhl R. Validation and clinical application of implantable loop recorders for diagnosis of atrial fibrillation in horses. Equine Vet J 2025 Mar;57(2):449-458.
    doi: 10.1111/evj.14112pubmed: 39031582google scholar: lookup
  6. Gong Q, LE X, Yu P, Zhuang L. Therapeutic advances in atrial fibrillation based on animal models. J Zhejiang Univ Sci B 2024 Feb 15;25(2):135-152.
    doi: 10.1631/jzus.B2300285pubmed: 38303497google scholar: lookup
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