title: Changes in echocardiographic variables of left ventricular size and function in a model of canine normovolemic anemia.
abstract: The objective of this study was to document changes in echocardiographic variables of left ventricular size and function noninvasively during acute normovolemic anemia. This model was developed as a pilot study with the purpose of providing baseline information to investigate the pathophysiology, and more specifically the effect on the heart, of canine babesiosis-induced anemia. The study group comprised of 11 mature healthy Beagle dogs that weighed between 9 and 15 kg. Severe normovolemic anemia was induced over a 3-4-day period by serial bleeding while maintaining normovolemia by autotransfusing plasma and infusing crystalloids. The dogs were then allowed to recover. Preanemic (mean Hct 46.7%, standard deviation [SD] 2.4%) echocardiographic variables of left ventricular performance (Fractional shortening, ejection fraction, end-systolic and end-diastolic ventricular volumes, cardiac index, and heart rate) were compared with those in the severely (mean Hct 15.3%, SD 1.1%), moderately (Hct mean 24.7%, SD 1.5%), and mildly (mean Hct 33.5%, SD 2.5%) anemic states, and between the anemic states. With the exception of end diastolic volume, there was a statistically significant (P < 0.05) increase in all variables in the severely anemic state vs. the preanemic and the mild and moderate anemic states. In concordance with previous invasive models, a hyperdynamic state of the left ventricle develops in response to experimentally induced acute canine normovolemic anemia in the conscious dog. Echocardiography has promise as a noninvasive technique of evaluating the cardiac changes in dogs having canine babesiosis.
authors.affiliation: Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, 0nderstepoort, 0110, South Africa. ozbroken@yahoo.co.uk
authors.forename: Tim C
authors.initials: TC
authors.lastname: Spotswood
authors.forename: Robert M
authors.initials: RM
authors.lastname: Kirberger
authors.forename: Lee M P K
authors.initials: LM
authors.lastname: Koma
authors.forename: Peter N
authors.initials: PN
authors.lastname: Thompson
authors.forename: David B
authors.initials: DB
authors.lastname: Miller
mesh_terms: D000740:Anemia / Q000000981:diagnostic imaging / Q000209:etiology / Q000662:veterinary*; D000818:Animals; D001404:Babesiosis / Q000150:complications / Q000662:veterinary*; D004195:Disease Models, Animal; D004283:Dog Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D008297:Male; D010865:Pilot Projects; D011237:Predictive Value of Tests; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000662:veterinary*