title: Echocardiographic predictors of survival in dogs with myxomatous mitral valve disease.
abstract: OBJECTIVE
  To evaluate vena contracta and other echocardiographic measures of myxomatous mitral valve disease (MMVD) severity in a multivariable analysis of survival in dogs.
  
  
  METHODS
  70 dogs diagnosed with MMVD from stored echocardiographic images that met study inclusion criteria.
  
  
  METHODS
  Left heart dimensions were measured as well as mitral regurgitant jet area/left atrial area (JAR), early mitral filling velocity (Evel), extent of mitral valve prolapse in right and left views (ProlR, ProlL), Prol indexed to aortic diameter (ProlR:Ao, ProlL:Ao), presence of a flail leaflet (FlailR, FlailL), and mitral regurgitation vena contracta diameter (VCR, VCL) indexed to aortic diameter (VCR:Ao, VCL:Ao). Follow-up from referring veterinarians was obtained by questionnaire or telephone to determine survival times. Inter- and intra-observer agreement was evaluated with Bland-Altman plots and weighted Kappa analysis. Survival was analyzed using Kaplan-Meier curves, logrank tests and Cox's proportional hazards.
  
  
  RESULTS
  Logrank analysis showed VCL:Ao, VCR:Ao, FlailL, ProlR:Ao, ProlL:Ao, left ventricular internal dimension in diastole indexed to aortic diameter (LVIDD:Ao) >2.87, left atrium to aorta ratio (LA/Ao) >1.6, and Evel >1.4 m/s were predictors of cardiac mortality. In a multivariable analysis, the independent predictors of cardiac mortality were Evel >1.4 m/s [hazard ratio (HR) 5.0, 95% confidence interval (CI) 2.5-10.3], FlailL (HR 3.1, 95% CI 1.3-7.9), and ProlR:Ao (HR 2.8, 95% CI 1.3-6.3).
  
  
  CONCLUSIONS
  Echocardiographic measures of mitral regurgitation severity and mitral valve pathology provide valuable prognostic information independent of chamber enlargement in dogs with MMVD.
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom. Electronic address: jsargent@rvc.ac.uk.
authors.forename: Julia
authors.initials: J
authors.lastname: Sargent
authors.affiliation: Department of Veterinary Medicine, Federal University of Lavras, Minas Gerais, Brazil.
authors.forename: Ruthnea
authors.initials: R
authors.lastname: Muzzi
authors.affiliation: Wood Street Veterinary Hospital, 74 Wood Street, Barnet EN5 4BW, United Kingdom.
authors.forename: Rajat
authors.initials: R
authors.lastname: Mukherjee
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: Sharlene
authors.initials: S
authors.lastname: Somarathne
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: Katherine
authors.initials: K
authors.lastname: Schranz
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: Hannah
authors.initials: H
authors.lastname: Stephenson
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Connolly
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Brodbelt
authors.affiliation: The Royal Veterinary College, Department of Veterinary Clinical Sciences, Hawkshead Lane, Hatfield AL9 7TA, United Kingdom.
authors.forename: Virginia Luis
authors.initials: VL
authors.lastname: Fuentes
mesh_terms: D000818:Animals; D015415:Biomarkers; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary*; D005260:Female; D006325:Heart Atria / Q000473:pathology; D006352:Heart Ventricles / Q000473:pathology; D008297:Male; D008944:Mitral Valve Insufficiency / Q000473:pathology / Q000662:veterinary*; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D015415:Biomarkers
keywords: Canine; Echocardiography; Mitral regurgitation; Prognosis