Objective: To determine if Buchanan’s vertebral heart scale can be applied to beagle dogs to establish reference values for this breed and to determine the possible influence of optimal lung inflation on the cardiac measurements.
Methods: The cardiac health of 19 beagle dogs was examined by echocardiography, electrocardiogram, non-invasive blood pressure measurement, complete blood count and serum chemistry profile. Right and left lateral recumbent radiographs of the thorax were obtained while the dogs were conscious and while under general anaesthesia with optimal lung inflation. The vertebral heart scale was measured in all radiographs.
Results: The mean (sd) vertebral heart scale in the beagle dogs was 10·3 (0·4) v, showing a significant difference from the mean vertebral heart scale of 9·7 (0·5) v in Buchanan’s original study with dogs of different breeds. Degree of inspiration had no significant effect on the vertebral heart scale.
Clinical Significance: The vertebral heart scale provides the veterinarian with a possible way of objectively evaluating canine heart size without having to rely on echocardiography. However, the results should be interpreted critically and breed-specific differences should be taken into account, especially with values slightly above the reference range.