title: Utility of measuring plasma N-terminal pro-brain natriuretic peptide in detecting hypertrophic cardiomyopathy and differentiating grades of severity in cats.
abstract: BACKGROUND
  Cats with hypertrophic cardiomyopathy (HCM) often have no clinical signs or subtle signs. Measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP) has been demonstrated in people to be highly specific for heart disease and also correlates with severity of HCM. NT-proBNP may also be valuable in detecting and grading HCM in cats, but results to date have been equivocal.
  
  
  OBJECTIVE
  The aims of this study were to evaluate NT-proBNP as a screening test for diagnosis of HCM in cats and determine an appropriate cut-off value and to determine if NT-proBNP concentrations correlated with severity of HCM in cats.
  
  
  METHODS
  Plasma NT-proBNP concentrations were measured in 201 cats using an ELISA designed for use in cats. Cats were classified using echocardiography as clinically healthy controls (n=99) or cats with equivocal (n=9), mild (n=15), moderate (n=17), or severe (n=61) HCM.
  
  
  RESULTS
  NT-proBNP concentrations (median; 25th-75th interquartile percentiles) in mildly (216.1; 87.6-392.5 pmol/L), moderately (282.7; 131.9-466.6 pmol/L), and severely (839.5; 655.3-1046.4 pmol/L) affected cats were significantly higher than those in healthy controls (18.9; 3.4-62.4 pmol/L). Concentrations in severely affected cats were significantly higher than in cats from other HCM groups. There was no significant difference between mild and moderate HCM. Cut-off values >49 pmol/L had a sensitivity of 97.8% and specificity of 66.7%; >100 pmol/L had a sensitivity of 92.4% and specificity of 93.9%; and >150 pmol/L had a sensitivity of 88% and a specificity of 100%.
  
  
  CONCLUSIONS
  NT-proBNP with a cut-off value of >100 pmol/L was useful in detecting even mild HCM. Cats with increased NT-proBNP concentrations should be examined by echocardiography.
authors: Clinic of Small Animal Medicine, Ludwig-Maximilians University, Munich, Germany. gwess@lmu.de
authors: Gerhard
authors: G
authors: Wess
authors: Patricia
authors: P
authors: Daisenberger
authors: Monia
authors: M
authors: Mahling
authors: Johannes
authors: J
authors: Hirschberger
authors: Katrin
authors: K
authors: Hartmann
mesh_terms: D000818:Animals; D002312:Cardiomyopathy, Hypertrophic / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D002371:Cat Diseases / Q000097:blood / Q000175:diagnosis*; D002415:Cats; D004452:Echocardiography / Q000662:veterinary; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain