Understanding cardiac parameters in rabbits using chest radiography and electrocardiography
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Abstract
Objective- To compare selected parameters of the heart, using the vertebral heart score (VHS) and electrocardiogram (ECG), between different breeds of healthy pet rabbits.
Materials and methods- Included in the analysis were 99 healthy rabbits, with no preselection for sex, age, or weight. Rabbits were classified according to their breed: Holland lop (n=51), Thai (n=32), or Netherland dwarf (n=16). Animals underwent anesthesia for a general surgical procedure. Anesthesia was performed using intramuscular ketamine-xylazine injection. Under anesthesia, chest radiography was performed to measure the size of the heart in the ventro-dorsal and right lateral recumbent positions, using the VHS method and ECG.
Result- The heart-to-thoracic size ratio was ≤60% in both positions. In the right recumbent position, there was no difference in heart size, width, and length and overall size between breeds. There was also no difference in heart rate and the following ECG parameters between the breeds: P wave (s), P wave (mV), PR interval (s), QRS complex (s), R wave (mV), and T wave (s). However, the QT interval (s) was different between the Holland lop and Thai breeds (P<0.05), with the difference being in the ST segment, with an elevation of >0.05 mV in 56.6% of animals and a maximum elevation of 0.12 mV. The mean electrical axis (MEA) was between -90º and 180º in 55.6% of animals, between -30º to -90º in 7.1%, and between 90º and 180º in 37.4%.
Conclusion- There were no significant differences in heart size or heart rate among the three breeds of rabbits. ECG showed a specific difference in the QT interval. ST elevation was different than that in normal dogs and cats, but remained within the normal values for humans. The MEA was between -90º and 180º.
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Wanwarang Wongcharoen, Arinthaya Phonminthikun, Narawutt Prasertwitthayakit, Rangsarit Kanchanawanit , Apichat Sukhonsan. 2014. Electrocardiography for medical student. 8th edition. Thailand, Chaingmai: Trick Thimk, 11-41.
Alexander JH. 2005. Comparative cardiac anatomy. In Paul AI (Ed.). Handbook of cardiac anatomy, physiology and devices. New Jersey: American International Standard institute, 81-91
Ali AS, Nasser V, Nikahval B, Alireza K. 2009. Comparison of the Effects of different doses of acepromazine-xylazine on the electrocardiogram in dogs. Iran J Vet Res 33(3), 208-215.
Anthony D, Sarah V. 2005. Basic ECG theory, recordings and interpretation. In Paul AI (Ed.). Handbook of cardiac anatomy, physiology and devices. New Jersey: American international standard institute, 191-201.
Atkins C, Bonagura J, Ettinger S, Fox P, Gordon S, Haggstrom J, Hamlin R, Keene B, Luis-Fuentes V, Stepien R. 2009. Guidelines for the diagnosis and treatment of canine chronic valvular heart disease. J Vet Intern Med 23(6), 1142–1150.
Buchanan JW, Bucheler J. 1995. Vertebral scale system to measure canine heart size in radiographs. J Am Vet Med Assoc 206(2), 194-199.
Canavese F, Dimeglio A, Barbetta D. 2014. Effect of thoracic arthrodesis in prepubertal New Zealand White rabbits on cardio-pulmonary function. Indian J Orthop 48(2), 184–192.
Cassu RN, Melchert A, Canoa JT, Martins PD. 2014. Sedative and clinical effects of the pharmacopuncture with xylazine in dogs. Acta Cir Bras 29(1), 47-52.
Chari YTH, John CBJr, Margaret MR. 2001. Effects of avertin versus xylazine-ketamine anesthesia on cardiac function in normal mice. Am J Physiol 281(5), 1938-1945.
Chitty J. 2015. Cardiovascular disease in rabbits. Companion Anim J 20(2), 74-78.
Carinci F, Martinelli M, Contaldo M, Santoro R, Pezzetti F, Lauritano D, Candotto V, Mucchi D, Palmieri A, Tagliabue A, Tettamanti 7. 2018. Focus on periodontal disease and development of endocarditis. J Biol Reg Homeos Ag 32(2), 143-147.
Deeb BJ, DiGiacomo RF. 2000. Respiratory diseases of rabbits. Vet Clin North Anim Exotic Anim Pract 3(2), 465-480.
Harcourt-Brown F. 2002. Textbook of Rabbit Medicine. 2nd edition. Burlington: Butterworth-Heinemann.
Jepsen GK, Pollard RE, Johnson LR. 2013. Vertebral heart scores in eight dog breeds. Vet Radiol Ultrasound 54(1), 3-8.
Larry T, Francis S, Mark O, Meg S. 2008. Electrocardiography. manual of canine and feline cardiology (4th Edition). Philadelphia: Saunders Elsevier. 464.
Lord B, Devine C, Smith S. 2010a. Congestive heart failure in two pet rabbits. Jo Small Anim Pract 52(1), 46-50.
Lord B, Boswood A, Petrie A. 2010b. Electrocardiography of the normal domestic pet rabbit. Vet Rec 167(25), 961-965.
Loscalzo J (Ed.). 2013. Harrison’s Cardiovascular Medicine. 2nd edition. United States: McGraw-Hill Education.
Marini RP, Li X, Harpster NK. 1999. Cardiovascular pathology possibly associated with ketamine/xylazine anaesthesia in Dutch belted rabbits. Lab Anim Sci 49(2), 153–160.
Nabi SU, Wani AR, Dey S. 2014. Radiographic measurements (vertebral heart scale) of popular breeds of dogs in India. Appl Biol Res 16 (2), 242-246.
Naglaa AG, Alaa G, Ayman A. 2015. Effect of repeated intravenous administration of xylazine on sedation, analgesia and ECG parameters in donkeys (Equus Asinus). Assiut Vet Med J 61(147), 130-136.
Pariaut R. 2009. Cardiovascular physiology and diseases of the rabbit. Vet Clin North Ame Exotic Anim Pract 12(1), 135-144.
Plonsey R. 1982. Electrocardiographic lead theory and lead systems. In Plonsey R, Liebman J, Gillette PC. (Eds.). Pediatric electrocardiography. Baltimore: Lippincott Williams & Wilkins. 26-39.
Praag EV. 2015. Congestive heart failure in rabbits. Retrieved January 19, 2019, from https://www.researchgate.net/publication/272151346_Congestive_heart_failure_in_rabbits.
Ruben CS, Matthew R, Dorcas O, Karen O, Chad RF, Corinne AW, Amanda GA, David AB. 2011. High doses of ketamine–xylazine anesthesia reduce cardiac ischemia–reperfusion injury in guinea pigs. J Am Assoc Lab Anim Sci 50(3), 349–354.
Shree VD, Milind SD, Basavraj SN. 2017. Periodontitis, bacteremia and infective endocarditis: a review study. Pediatr Infect Dis 5(3): e41067.
Turner GA, Ayres DA, Lima L. 2015. Determination of normal echocardiographic, electrocardiographic, and radiographic cardiac parameters in the conscious New Zealand White rabbit. J Exotic Pet Med 24(2), 223-234.
Weerakhun S. 2015. Rabbit Gastrointestinal Syndrome. Processing of the 16th KhonKaen university veterinary international annual conference, KhonKaen University, KhonKaen, Thailand.
Wendy AW. 2011. Cardiovascular disease in small animal medicine. 3rd ed. London: Manson Publishing Ltd.