Effect of body condition score on the interobserver variability of vertebral heart scale assessment in dogs

The Vertebral Heart Scale (VHS) is widely known and used as an objective standard for the evaluation of cardiomegaly on thoracic radiographs. It plays therefore an important role in assessing the severity of canine heart disease. The Body Condition Score (BCS) is a nine-scale body condition scoring system used to objectively document the body condition in dogs. Obese animals might have a widened precardiac and postcardiac mediastinum, fat deposits between the sternum and lungs or heart, as well as increased pericardial fat that could complicate cardiac silhouette evaluation. These factors could result in a higher interobserver variability in the assessment of VHS in obese dogs. The purpose of this study was therefore to investigate if obese dogs (BCS 7/9, 8/9, and 9/9) have more variability in the interobserver VHS measurement compared to dogs with a normal BCS (BCS 4/9 and 5/9). The VHS was measured by three trained observers in right lateral radiographs of 18 obese dogs and 33 dogs with a normal BCS admitted to a private referral centre for different medical reasons. No significant difference in variability between the three observers was seen in dogs with a normal BCS versus obese dogs. In conclusion,BCSdoes not affect the reliability of vertebral heart scale assessment among veterinarians.