Abstract
The electrocardiogram of 9 horses was continuously recorded for 24 h with Holter monitoring to examine the variations in heart rate and rhythm during daily routine procedures and at night. Three horses had transient sinus bradycardia, and 3 had periods of sinus tachycardia. Heart blocks were detected in 3 horses, and all horses had periods of sinus arrhythmia. These changes in the heart rate and rhythm were apparently caused by variations in autonomic nervous system tone and they are probably “normal” findings in resting, undisturbed horses. Ventricular premature depolarisations were not observed in any horse, but some single supraventricular premature contractions were detected. There was preliminary evidence that in order to register the real resting heart rate and rhythm of a horse the ECG should be recorded over a long period, and also at night and without the presence of the investigator.
Keywords: tachycardia, bradycardia, sinus arrhythmia, heart block
Sammanfattning
Elektrokardiografi gjordes på 9 hästar under 24 t. Tre hästar hade övergående sinusbradykardi och 3 hade periodisk sinustakykardi. Tre hästar hade ledningsstörningar, och hos alla djur förekom periodvisa sinusarrytmier. Dessa förändringar i hjärtfrekvens och -rytm förursakades sannolikt av variation i det autonoma nervsystemets tonus, och de är sannolikt “normala” fynd hos hästar i vila. Ventrikulära ekstrasystoler förekom inte, men några enskilda atriella ekstrasystoler registrerades. Dessa fynd tyder på, att EKG borde kanske registreras också på natten och över ett långt period, om man vill studera den värkliga hjärtrytmen och -frekvensen hos hästen i vila.
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References
- Brodsky M, Wu D, Denes P, Kanakis C, Rosen KM. Arrhythmias documented by 24 hour continuous electrocardiographic monitoring in 50 male medical students without apparent heart disease. Amer. J. Cardiol. 1977;39:390–395. doi: 10.1016/S0002-9149(77)80094-5. [DOI] [PubMed] [Google Scholar]
- Brownlie SE. Evaluation for veterinary use of the Chiltern box: A device for home electrocardiographic monitoring. Vet. Rec. 1987;120:85–87. doi: 10.1136/vr.120.4.85. [DOI] [PubMed] [Google Scholar]
- Fregin GF: The cardiovascular system. In: Mansmann RA, McAllister ES, Pratt PW (eds.): Equine Medicine and Surgery. American Veterinary Publications, Santa Barbara, 1982, 3. ed, 645–704.
- Gatti L, Holmes JR. ECG recording at rest and during exercise in the horse. Equine vet. Educ. 1990;2:28–30. doi: 10.1111/j.2042-3292.1990.tb01374.x. [DOI] [Google Scholar]
- Hilwig RW: Cardiac arrhythmias. In: Robinson NE (ed.): Current Therapy in Equine Medicine 2. WB Saunders Company, Philadelphia, 1987. p 154–164.
- Kennedy HL, Caralis DG. Ambulatory Electrocardiography, A Clinical Perspective. Ann. Intern. Med. 1977;87:729–739. doi: 10.7326/0003-4819-87-6-729. [DOI] [PubMed] [Google Scholar]
- McGuirk SM, Muir WW. Diagnosis and treatment of cardiac arrhythmias. Vet. Clin. North Amer. Equine Pract. 1985;1:353–370. doi: 10.1016/S0749-0739(17)30760-5. [DOI] [PubMed] [Google Scholar]
- Miller MS, Tilley LP: Electrocardiography. In: Fox PR (ed.): Canine and Feline Cardiology. Churchill Livingstone, New York, 1988, 43–89.
- Romano M, Clarizia M, Onofrio E, Caiazzo MR, Adinolfi L, Cutillo S, Chiariello M, Condorelli M. Heart rate, PR, and QT intervals in normal children: A 24-hour Holter monitoring study. Clin. Cardiol. 1988;11:839–842. doi: 10.1002/clc.4960111208. [DOI] [PubMed] [Google Scholar]
- Tilley LP: Special methods for analyzing and treating arrhythmias. In: Essentials of Canine and Feline Electrocardiography: Interpretation and Treatment. Lea & Febiger, Philadelphia, 1985, 2. ed., 317–354.
- Viitasalo MT, Kala R, Eisalo A. Ambulatory electrocardiographic recording in endurance athletes. Br. Heart J. 1982;47:213–220. doi: 10.1136/hrt.47.3.213. [DOI] [PMC free article] [PubMed] [Google Scholar]