Systemic inflammation and endothelial dysfunction in dogs with congestive heart failure.

BACKGROUND: Congestive heart failure (CHF) is associated with endothelial dysfunction in people and in dogs with experimentally induced CHF, but this is not well characterized in dogs with naturally occurring CHF. HYPOTHESIS/
OBJECTIVES: To evaluate endothelial function via assessment of reactive hyperemia (RH) in healthy dogs and dogs with CHF, and to assess for relationships with plasma biomarkers of vascular function and clinical markers of disease severity. ANIMALS: Twenty client-owned animals with CHF due to myxomatous mitral valve disease (n = 15) or dilated cardiomyopathy (n = 5) and 17 healthy control dogs.
METHODS: Prospective case-controlled observational study. Dogs underwent blood sampling, echocardiography, and Doppler assessment of brachial artery velocity (VTI) at baseline and during reactive hyperemia (RH-VTI). RH-VTIs between control dogs and dogs with CHF were compared, and the relationships between RH-VTI, clinical parameters, and plasma biomarkers were assessed.
RESULTS: Dogs with CHF (96.5 ± 51.7%) had an attenuated % increase in VTI during RH compared to healthy controls (134.8 ± 58.7%; P = .04). Increasing ISACHC class (R(2) = 0.24; P = .004), plasma NT-proBNP (R(2) = 0.15; P = .03) and CRP (R(2) = 0.2; P = .02) were associated with reduced RH-VTI. Increased plasma CRP, NO(x) , and NT-proBNP concentrations were found in dogs with CHF (P < .02 for all). No differences were detected in other plasma markers. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with CHF have an attenuated RH response, and increased plasma CRP and NO(x) concentrations. Doppler assessment of RH velocity could represent a novel noninvasive method of evaluating endothelial function in the dog.