Dilated cardiomyopathy in cats: survey of veterinary cardiologists and retrospective evaluation of a possible association with diet.

INTRODUCTION/OBJECTIVES: The objectives were to conduct a survey of cardiologists on their recent experiences with cats that have dilated cardiomyopathy (DCM) and to retrospectively review individual cases of feline DCM. ANIMALS, MATERIALS AND METHODS: Part one: A survey was distributed to cardiologists with questions regarding caseload and clinical management of cats with DCM diagnosed over the past two years. Part two: Cardiologists completing the survey were invited to submit data from cats recently diagnosed with DCM. Data on signalment, clinical signs, diet, echocardiographic measurements and outcome were recorded. RESULTS: Part one: From 52 completed surveys, many cardiologists responded that measuring and supplementing taurine and recommending a diet change in cats with DCM are common practices. Few (15%) cardiologists reported an increase in the number of feline DCM cases over the past two years, although some had cases that improved even if taurine deficiency was not present. Part two: Twenty of 37 (54%) cats ate low pea/lentil (low PL) diets, and 14/37 (38%) ate high PL diets at the time of diagnosis; three had incomplete diet information. Two of 13 cats (15%) in which taurine was measured had levels below the reference range. After adjusting for other variables, cats eating high PL diets that changed diets after diagnosis had a significantly longer survival time than that of cats eating high PL diets that did not change diets after diagnosis (P = 0.025). CONCLUSIONS: Additional research is warranted to determine whether there could be a possible association between diet and DCM in cats.

Plasma growth differentiation factors 8 and 11 levels in cats with congestive heart failure secondary to hypertrophic cardiomyopathy.

OBJECTIVES: Growth differentiation factor (GDF) 11 has been shown to reduce cardiac hypertrophy in mice. Low levels of GDF-11 are associated with cardiac hypertrophy in humans. The authors hypothesized that plasma GDF-11 level is decreased in cats with hypertrophic cardiomyopathy (HCM). Given the close homology between GDF-11 and myostatin/GDF-8, GDF-8 levels were also assessed. ANIMALS: Thirty-seven client-owned cats were enrolled, including cats with normal cardiac structure (n = 16), cats with HCM or hypertrophic obstructive cardiomyopathy (HOCM; n = 14), and cats with HCM and congestive heart failure (CHF; n = 7). METHODS: Plasma samples were analyzed for GDF-8 and GDF-11 using liquid chromatography tandem-mass spectrometry. Levels of GDF-8 and GDF-11 were compared between cats with normal cardiac structure, HCM or HOCM, and CHF. RESULTS: No differences in GDF-11 concentrations were found between cats with normal cardiac structure and cats with HCM/HOCM, with or without history of CHF. Decreased GDF-8 concentrations were detected in cats with CHF compared to cats with HCM/HOCM without history of CHF (p=0.031) and cats with normal cardiac structure (p=0.027). Growth differentiation factor 8 was higher in cats with HOCM compared to those with CHF (p=0.002). No statistical difference was noted in GDF-8 level as a function of age, weight, or body condition score. CONCLUSIONS: Plasma GDF-11 was not different between cats with HCM/HOCM and cats with normal cardiac structure regardless of age. Plasma GDF-8 was decreased in cats with CHF compared to cats with normal cardiac structure and cats with asymptomatic HCM/HOCM, suggesting a possible role in CHF development.

Extracardiac intrapericardial myxosarcoma causing right ventricular outflow tract obstruction in a dog.

A 13-year-old male castrated pomeranian cross was referred for evaluation of episodes of collapse and a suspected cardiac mass. The presence of a mass at the base of the heart within the pericardial space was confirmed by echocardiography. Additional diagnostics included computed tomography, ultrasound-guided fine-needle aspirate, and thoracic radiographs. The mass was surgically debulked and diagnosed as myxosarcoma via histopathology. This case report describes the diagnostic imaging, laboratory findings, and short-term positive clinical outcome of a dog with a myxosarcoma in a previously undescribed location.

Association between Survival Time and Changes in NT-proBNP in Cats Treated for Congestive Heart Failure.

BACKGROUND: Reductions in N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations after treatment have been associated with improved survival in people with congestive heart failure (CHF), but have not been reported in cats with CHF. OBJECTIVES: To evaluate changes in NT-proBNP concentrations in cats with CHF after treatment and determine whether serial NT-proBNP measurements provide prognostic information. ANIMALS: Thirty-one client-owned cats. METHODS: Prospective, observational study in cats with new onset CHF secondary to cardiomyopathy. Concentrations of NT-proBNP were measured within 4 hours of admission to the hospital, on the day of discharge, and at re-evaluation 7-10 days later. RESULTS: Median NT-proBNP concentrations decreased significantly from admission (1,713 pmol/L [range, 160-3,784 pmol/L]) to discharge (902 pmol/L [range, 147-3,223 pmol/L]); P = .005) and from admission to re-evaluation (1,124 pmol/L [range, 111-2,727 pmol/L]; P = .024). Median survival time was 109 days (range, 1-709 days), with 5 cats still alive at the time of analysis. Cats with a larger percent decrease in NT-proBNP from admission to discharge had a longer survival time (P = .048). Cats with evidence of active CHF at the time of re-evaluation (P = .010) and cats whose owners had difficulty administering medications (P = .045) had shorter survival times. CONCLUSIONS AND CLINICAL IMPORTANCE: Cats with a larger percent decrease in NT-proBNP during hospitalization and no evidence of CHF at the time of re-evaluation had longer survival times. Additional studies are needed to determine whether NT-proBNP can help guide treatment in cats with CHF.