Accurate heart evaluation is essential in veterinary care for diagnosing and monitoring cardiac conditions in pets. Thoracic radiographs and imaging are key tools, but a single view may miss abnormalities.
A comprehensive approach—including multiple views, standardized measurements, and assessment of surrounding structures—enhances diagnostic accuracy and leads to better treatment decisions.
Why Is It Important to Take at Least Two Views of the Heart?
Taking only one X-ray of the heart can lead to missed details. A single image might not show changes in heart size or shape, which could delay diagnosis. Veterinarians recommend at least two views – right lateral and ventral-dorsal (VD). The right lateral view helps assess heart size, while the VD view gives a clearer picture of chamber enlargement and blood flow.
If a dog cannot lie on its back, a dorsal-ventral (DV) view can be used instead. Sometimes, adding a left lateral view provides even more information, helping detect subtle changes in heart function that could affect treatment decisions.
How Does the Vertebral Heart Score Help in Heart Evaluation?
The Vertebral Heart Score (VHS) is a simple way to measure heart size using X-rays. Instead of guessing if a heart is too big, veterinarians use this technique to get a more accurate assessment. VHS is calculated by measuring the long and short axes of the heart on a lateral view and comparing them to the pet’s vertebrae, starting at T4.
A normal VHS for dogs is usually between 8.5 and 10.7, though breed differences exist. Some breeds have naturally smaller values (greyhound), while brachycephalic breeds (French bulldog) may appear to have larger hearts. In cats, a VHS of 8.0 or lower is considered normal. Tracking VHS over time helps detect early signs of heart disease, making it a valuable tool in veterinary care.
Why Should You Learn About Variations of “Normal” Heart Sizes?
Not all patients have the same heart size, even if they are completely healthy. Understanding breed and individual variations is key to accurate diagnosis.
- Brachycephalic breeds (e.g., Bulldogs, Pugs) often have larger-looking hearts due to their chest shape.
- Deep-chested breeds (e.g., Greyhounds, Dobermans) tend to have a smaller, more elongated cardiac silhouette.
- Age and weight can also influence heart size.
Veterinarians should evaluate multiple radiographs over time to build experience in distinguishing normal variations from actual heart disease.
How Can Other Structures Help You Evaluate the Heart?
The heart is not the only organ that can show signs of disease. Taking the time to review the lungs, blood vessels, and abdomen can give important clues about heart health. Pulmonary blood vessels should be a normal size; if they are too large, it could suggest fluid overload or heart disease. Checking for lung congestion or fluid buildup can help confirm heart-related problems as well.
An enlarged liver may also be a sign of heart failure, as blood can back up into the liver when the heart is not pumping effectively. By looking at the whole chest and abdomen anatomy, veterinarians can gather more information to make a confident diagnosis.
When Should You Seek a Second Opinion for a Chest Radiograph?
Some heart conditions are obvious, but others can be tricky to spot. If an X-ray shows subtle or borderline changes, it’s always a good idea to get a second opinion. Cardiologists and experienced radiologists can help interpret difficult cases and suggest additional tests if needed. Expert advice such as this can lead to more accurate diagnoses and better treatment decisions.
Making Heart Evaluations Easier for Your Practice
Evaluating heart health using X-rays requires a careful approach. If you need guidance on thoracic radiograph interpretation or improving your veterinary medicine practice, contact AxisVet for expert advice and to learn more about our services.