title: Mitral valve repair under cardiopulmonary bypass in small-breed dogs: 48 cases (2006-2009).
abstract: OBJECTIVE
  To determine whether mitral valve repair (MVR) under cardiopulmonary bypass would be an effective treatment for mitral regurgitation in small-breed dogs.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  48 small-breed dogs (body weight, 1.88 to 4.65 kg [4.11 to 10.25 lb]; age, 5 to 15 years) with mitral regurgitation that underwent surgery between August 2006 and August 2009.
  
  
  METHODS
  Cardiopulmonary bypass was performed with a cardiopulmonary bypass circuit. After induction of cardiac arrest, a mitral annuloplasty was performed, and the chordae tendineae were replaced with expanded polytetrafluoroethylene chordal prostheses. After closure of the left atrium and declamping to restart the heart, the thorax was closed.
  
  
  RESULTS
  Preoperatively, cardiac murmur was grade 3 of 6 to 6 of 6, thoracic radiography showed cardiac enlargement (median vertebral heart size, 12.0 vertebrae; range, 9.5 to 14.5 vertebrae), and echocardiography showed severe mitral regurgitation and left atrial enlargement (median left atrium-to-aortic root ratio, 2.6; range, 1.7 to 4.0). 45 of 48 dogs survived to discharge. Three months after surgery, cardiac murmur grade was reduced to 0/6 to 3/6, and the heart shadow was reduced (median vertebral heart size, 11.1 vertebrae, range, 9.2 to 13.0 vertebrae) on thoracic radiographs. Echocardiography confirmed a marked reduction in mitral regurgitation and left atrium-to-aortic root ratio (median, 1.7; range, 1.0 to 3.0).
  
  
  CONCLUSIONS
  We successfully performed MVR under cardiopulmonary bypass in small-breed dogs, suggesting this may be an effective surgical treatment for dogs with mitral regurgitation. Mitral valve repair with cardiopulmonary bypass can be beneficial for the treatment of mitral regurgitation in small-breed dogs.
authors.affiliation: Veterinary Cardiovascular Medicine and Surgery Unit, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, Chiyoda-ku 102-8275, Tokyo, Japan. uechi.masami@nihon-u.ac.jp
authors.forename: Masami
authors.initials: M
authors.lastname: Uechi
authors.forename: Takahiro
authors.initials: T
authors.lastname: Mizukoshi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Mizuno
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizuno
authors.forename: Kayoko
authors.initials: K
authors.lastname: Harada
authors.forename: Takashi
authors.initials: T
authors.lastname: Ebisawa
authors.forename: Junichirou
authors.initials: J
authors.lastname: Takeuchi
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Sawada
authors.forename: Shuhei
authors.initials: S
authors.lastname: Uchida
authors.forename: Asako
authors.initials: A
authors.lastname: Shinoda
authors.forename: Arane
authors.initials: A
authors.lastname: Kasuya
authors.forename: Masaaki
authors.initials: M
authors.lastname: Endo
authors.forename: Miki
authors.initials: M
authors.lastname: Nishida
authors.forename: Shota
authors.initials: S
authors.lastname: Kono
authors.forename: Megumi
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology; D001947:Breeding; D002315:Cardiopulmonary Bypass / Q000662:veterinary*; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary; D005260:Female; D008297:Male; D008943:Mitral Valve / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000601:surgery / Q000662:veterinary*; D011446:Prospective Studies; D016896:Treatment Outcome