CONGESTIVE HEART FAILURE IN DOGS IS ASSOCIATED WITH ENHANCED PLATELET-LEUKOCYTE AGGREGATES - A MARKER FOR PLATELET ACTIVATION.
I Tarnow1, LH Olsen2, SHS Andreasen2, SG Moesgaard2, CE Rasmussen2, AT Kristensen1, T Falk2. 1Departments of Small Animal Clinical Sciences and 2Animal and Veterinary Basic Sciences, Faculty of Life Science, University of Copenhagen, Denmark.
Chronic congestive heart failure (CHF) in humans is associated
with abnormal hemostasis, and changes in hemostatic biomarkers
carry a poor prognosis. CHF in dogs has been associated with
plasma markers of hypercoagulability, however, platelet activation
markers have not been investigated in dogs with clinical signs of
heart disease. We hypothesized that platelet surface activation
markers are higher in dogs with CHF compared to age-matched
controls without clinical signs of heart failure.
Dogs with compensated congestive heart failure (n 5 21; age 9.9 _
2.8 years) caused by acquired heart disease and age-matched control
dogs (n 5 19; age 9.5 _ 2.0 years) without signs of heart failure were
studied in parallel on same days. Platelet surface P-selectin (CD62P
binding) expression, activation of platelet surface GPIIb-IIIa (CAP1
binding),monocyte-platelet (MPAs) and neutrophil-platelet aggregates
(NPAs) defined as leukocytes positive for CD61 were measured by
whole blood flow cytometry asmarkers of platelet activation. For every
dog platelet activation was assessed in unstimulated samples, and in response
to exogenously added adenosine diphosphate (ADP), thrombin
and a synthetic thromboxane A2 analogue 1 epinephrine. Complete
blood count and biochemical screening were performed in all dogs.
Dogs with CHF had higher MPAs (p 5 0.014) and NPAs ( p 5
0.021) compared to controls (2-way analysis of variance for repeated
measurements).