Staging heart disease in Dogs
Stage A - Dogs at high risk for heart disease (KCC)
Stage B - a murmur is heard but there are no visible signs of heart failure.
B1 - The heart does not appear enlarged or changed on x-ray.
B2 - The heart does appear enlarged or changed on X-ray
Stage C - Evidence of heart failure is visible and treatment is necessary.
Stage D - Heart failure is getting hard to manage and is not responding to standard treatment.