Evaluation of plasma C-terminal atrial natriuretic peptide in healthy cats and cats with heart disease

Abstract

Background: The clinical implications of evaluating C-terminal atrial natriuretic peptide (ANP) concentration in cats are still controversial. Hypothesis: The objective of this study was to investigate the relationship between plasma C-terminal ANP concentration and left atrial pressure (LAP) in healthy cats with volume overload (study 1), and to compare plasma C-terminal ANP in normal cats and cats with cardiomyopathy (study 2). Animals: Five healthy adult cats were used in study 1, and clinically healthy cats (n = 8) and cats with cardiomyopathy (n = 14) were used in study 2. Methods: In study 1, cats were anesthetized and given acetated Ringer's solution (100mL/kg/h for 60 minute) via the cephalic vein. Hemodynamic measurements and blood samples, collected from the jugular vein, were performed at 10-min intervals. In study 2, blood samples from normal cats and cats with cardiomyopathy were collected from the cephalic vein. The plasma C-terminal ANP concentration was determined by radioimmunoassay for human α-ANP. Results: In study 1, volume overload significantly increased the C-terminal ANP concentration and LAP from baseline. The C-terminal ANP concentration was strongly correlated with the mean LAP. In study 2, age, E wave velocity, and the ratios of the left atrium to aorta were significantly higher in the cats with cardiomyopathy compared with the normal cats. The C-terminal ANP concentration was significantly higher in the cats with cardiomyopathy compared with the normal cats. Conclusions and Clinical Importance: Our results suggest that the measurement of plasma C-terminal ANP in cats may provide additional information for the diagnosis of heart disease. Copyright © 2008 by the American College of Veterinary Internal Medicine.