title: Survival characteristics and prognostic variables of dogs with mitral regurgitation attributable to myxomatous valve disease.
abstract: BACKGROUND
  There are few studies evaluating the natural history and prognostic variables in chronic mitral valve disease (CMVI) in a heterogeneous population of dogs.
  
  
  OBJECTIVE
  To estimate survival and prognostic value of clinical and echocardiographic variables in dogs with CMVI of varying severity. Five hundred and fifty-eight dogs belonging to 36 breeds were studied.
  
  
  METHODS
  Dogs were included after clinical examination and echocardiography. Long-term outcome was assessed by telephone interview with the owner.
  
  
  RESULTS
  The mean follow-up time was 22.7 +/- 13.6 months, and the median survival time was 19.5 +/- 13.2 months. In univariate analysis, age>8 years, syncope, HR>140 bpm, dyspnea, arrhythmias, class of heart failure (International Small Animal Cardiac Health Council), furosemide therapy, end-systolic volume-index (ESV-I)>30 mL/m(2), left atrial to aortic root ratio (LA/Ao)>1.7, E wave transmitral peak velocity (Emax)>1.2 m/s, and bilateral mitral valve leaflet engagement were associated with survival time when all causes of death were included. For the cardiac-related deaths, all the previous variables except dyspnea and EDV-I>100 mL/m(2) were significantly associated with survival time. Significant variables in multivariate analysis (all causes of death) were syncope, LA/Ao>1.7 m/s, and Emax>1.2 m/s. For cardiac-related death, the only significant variable was LA/Ao>1.7.
  
  
  CONCLUSIONS
  Mild CMVI is a relatively benign condition in dogs. However, some clinical variables can identify dogs at a higher risk of death; these variables might be useful to identify individuals that need more frequent monitoring or therapeutic intervention.
authors.affiliation: Department Patologia Animale, Faculty Veterinary Medicine, Grugliasco, Italy. mborgare@vet.k-state.edu
authors.forename: M
authors.initials: M
authors.lastname: Borgarelli
authors.forename: P
authors.initials: P
authors.lastname: Savarino
authors.forename: S
authors.initials: S
authors.lastname: Crosara
authors.forename: R A
authors.initials: RA
authors.lastname: Santilli
authors.forename: D
authors.initials: D
authors.lastname: Chiavegato
authors.forename: M
authors.initials: M
authors.lastname: Poggi
authors.forename: C
authors.initials: C
authors.lastname: Bellino
authors.forename: G
authors.initials: G
authors.lastname: La Rosa
authors.forename: R
authors.initials: R
authors.lastname: Zanatta
authors.forename: J
authors.initials: J
authors.lastname: Haggstrom
authors.forename: A
authors.initials: A
authors.lastname: Tarducci
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000401:mortality*; D004285:Dogs; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000662:veterinary*; D008297:Male; D008944:Mitral Valve Insufficiency / Q000209:etiology / Q000401:mortality / Q000662:veterinary*; D015999:Multivariate Analysis; D011379:Prognosis; D015996:Survival Rate; D014463:Ultrasonography