Why is cardiac radiology so difficult?

Radiography must always be interpreted with knowledge of the patient's history and clinical signs. The most critical use of radiography in patients with suspected cardiac disease is to determine if patients presenting with acute severe respiratory signs are in cardiac failure or if their signs are the result of some other condition, such as pneumonia VHS values tend to increase in dogs with cardiac disease, but this does not mean that measuring the cardiac silhouette aids radiographic diagnosis of canine cardiac disease. Diagnosis of congenital cardiac anomalies cannot be based on radiographs alone.