Dog Vertebral Heart Score and Cardiac Monitoring

The vertebral heart score is a standardized radiographic measurement used to screen dogs for cardiac enlargement, enabling earlier detection of progressive heart disease.

Key Facts

VHS measures cardiac shadow length normalized to vertebral body size on lateral chest X-ray
Normal VHS is 8.5-10.5 vertebral units depending on breed-specific norms
Cavalier King Charles Spaniels have breed-specific VHS guidelines due to high MVD prevalence
Serial VHS measurements detect progressive cardiac enlargement before clinical signs develop
The EPIC trial demonstrated benefit of early medication before congestive heart failure onset

Welfare Considerations

Heart disease is the leading cause of death in small breed dogs, and detecting cardiac enlargement before heart failure develops allows early intervention that delays the onset of debilitating symptoms. Dogs in subclinical heart disease before treatment may experience subtle exercise intolerance and reduced enjoyment of activity without owners recognizing the cause. The EPIC trial found that pimobendan given when heart enlargement reaches a threshold delayed heart failure onset by 15 months on average - representing over a year of better welfare for affected dogs.

What You Can Do

Establish a baseline VHS in predisposed breeds at age 1-2 years and repeat annually
Follow breed-specific VHS guidelines for Cavaliers and other high-prevalence breeds
Discuss the EPIC trial criteria for early pimobendan therapy with your veterinarian
Recognize early clinical signs including exercise intolerance, coughing at night, and faster resting breathing
Refer to a veterinary cardiologist for echocardiographic assessment when cardiac enlargement is detected