Echocardiogram for Dogs: What to Expect

What is an echocardiogram?

An echocardiogram — commonly called an "echo" — is an ultrasound of the heart. It uses sound waves to create a real-time, moving picture of your dog's heart, allowing a veterinary cardiologist to see the chambers, valves, and walls as they pump. No radiation is involved, and the procedure is painless.

If your dog is being screened for Dilated Cardiomyopathy (DCM) or has already been diagnosed, the echocardiogram is one of the two cornerstone tests in cardiac care. It gives your cardiologist a direct look at the heart's structure and function — information that no other test can provide.

Why your dog needs an echo

An echocardiogram answers the questions that matter most in heart disease:

• Is the heart enlarged? In DCM, the left ventricle dilates over time. The echo measures exactly how big the chambers have become.
• Is the heart pumping effectively? The echo quantifies how well the heart muscle contracts with each beat.
• Are the valves leaking? Doppler ultrasound (part of the echo) can detect and grade valve insufficiency.
• Is there fluid buildup? The echo can reveal pericardial effusion or signs of congestion.
• How is treatment working? Serial echos track progression and response to medication over time.

A stethoscope can detect a murmur or irregular rhythm, but it cannot tell you how much the heart has changed structurally. The echo fills that gap.

How the procedure works: step by step

Knowing what to expect takes the anxiety out of the appointment — for you and your dog.

Before the appointment

• No fasting required. Unlike some diagnostic tests, your dog can eat and drink normally.
• Bring your medications list. The cardiologist needs to know every drug and supplement your dog takes.
• Bring previous records. If your dog has had prior echos or Holter results, bring them or have them sent ahead. Comparisons between studies are extremely valuable.
• Plan for about 30–60 minutes. The echo itself takes 20–40 minutes, but allow extra time for check-in and the consult afterward.

During the echo

1. Positioning. Your dog will typically lie on a specially designed table with a cutout. They lie on their side (usually right side first, then left) so the ultrasound probe can be placed against the chest wall from below. Some clinics use a padded mat on a regular table instead.

2. Fur clipping. A small patch of fur on each side of the chest may be shaved to improve image quality. The ultrasound gel doesn't transmit well through thick fur. Some cardiologists skip shaving if the coat is thin enough.

3. Gel application. Warm ultrasound gel is applied to the skin. It's water-based and washes off easily.

4. The scan. The cardiologist moves the probe across the chest, capturing images from multiple angles. You'll see the heart moving on the monitor in real time. They'll take still frames and video clips, and run Doppler measurements to assess blood flow.

5. Your dog's experience. Most dogs tolerate echos remarkably well. The probe pressure is gentle, and many dogs relax or even doze off during the exam. Treats and gentle restraint from a technician are usually all that's needed.

Sedation: usually not necessary

One of the most common questions owners ask is whether their dog will need sedation. The answer is almost always no. The vast majority of echocardiograms are performed on awake, unsedated dogs. Sedation can actually alter heart rate and function, potentially affecting the accuracy of measurements.

Sedation may be considered for dogs that are:

• Extremely anxious or fractious
• Aggressive when handled by strangers
• Panting so heavily that image quality is compromised

If sedation is needed, the cardiologist will choose protocols that have minimal effects on cardiac function.

The measurements that matter

The echo generates a lot of data, but four key measurements are central to DCM assessment:

LVIDd (Left Ventricular Internal Dimension in Diastole)

This measures the width of the left ventricle when it's relaxed and filling with blood. In DCM, this number increases as the chamber dilates.

• What it tells you: How enlarged the heart has become.
• In plain language: Think of it as how stretched out the heart is when it's "resting" between beats.
• Normal varies by breed and body weight. A Doberman's normal LVIDd is different from a Cavalier King Charles Spaniel's. Cardiologists use breed-specific reference ranges.

LVIDs (Left Ventricular Internal Dimension in Systole)

This measures the left ventricle when it's fully contracted — squeezed down to push blood out.

• What it tells you: How well the heart empties with each beat.
• In plain language: If this number is too high, the heart isn't squeezing down enough. It's "flabby."

FS% (Fractional Shortening)

This is calculated from LVIDd and LVIDs. It represents the percentage change in the ventricle's diameter between relaxation and contraction.

Normal FS% in most dogs: 25–45%. In Dobermans, values below 20% are concerning, and below 15% indicates significant systolic dysfunction.

• In plain language: FS% is a direct measure of how hard the heart is squeezing. A low number means the pump is weak.

EF% (Ejection Fraction)

This estimates the percentage of blood that's ejected from the left ventricle with each beat.

Normal EF%: approximately 50–70%. Below 40% is considered reduced and is a hallmark of DCM.

• In plain language: If the heart fills with 100 mL of blood, a healthy heart pumps out 50–70 mL. A DCM-affected heart may only pump out 25–35 mL.

Other findings your cardiologist may note

• E-point septal separation (EPSS): How close the mitral valve gets to the septum during opening. Increased EPSS suggests poor contractility.
• Left atrial enlargement: The left atrium may dilate as the failing ventricle backs up blood. This is measured as the LA:Ao ratio (left atrium to aorta ratio). Above 1.6 is generally considered enlarged.
• Mitral regurgitation: Leakage of the mitral valve, common in DCM as the heart stretches and the valve leaflets no longer meet properly.

Understanding your results

Your cardiologist should walk you through the findings in person, but here's a general framework:

Normal echo

All measurements fall within breed-specific reference ranges. Heart structure and function look good. Continue annual screening if your dog is in an at-risk breed.

Equivocal or borderline

Some measurements are at the upper or lower edge of normal. This doesn't mean your dog has DCM — but it does mean closer follow-up is warranted, typically a recheck echo in 3–6 months rather than 12.

Occult (preclinical) DCM

The echo shows changes consistent with early DCM — mild chamber enlargement, mildly reduced function — but your dog has no clinical symptoms. This is where early intervention with medications like pimobendan can make a meaningful difference in how long the occult stage lasts.

Overt DCM / Congestive Heart Failure

Significant chamber dilation, reduced contractility, and possibly evidence of fluid accumulation. Your dog may already be showing symptoms: cough, exercise intolerance, rapid breathing at rest. Treatment becomes more intensive at this stage.

How often should the echo be repeated?

The frequency depends on your dog's status:

• Healthy dogs in at-risk breeds (screening): Once per year, starting at age 3–4.
• Equivocal findings: Every 3–6 months until a trend is clear.
• Occult DCM on treatment: Every 6–12 months, depending on stability.
• Overt DCM / CHF: Every 3–6 months, or sooner if symptoms change.

Your cardiologist may adjust this schedule based on individual circumstances. Changes in symptoms should always prompt a sooner recheck.

What an echo costs

Echocardiogram costs vary by location, clinic type, and whether a board-certified cardiologist performs the study.

Typical cost range: $300–$600. University teaching hospitals and specialty clinics tend to be at the higher end. Mobile cardiologist services and breed club screening events may be at the lower end.

Some things that affect price:

• Geographic region. Coastal cities tend to be more expensive.
• Full study vs. screening echo. A comprehensive diagnostic echo takes longer and costs more than a focused screening study.
• Consultation fee. Some clinics include the cardiologist's interpretation in the echo fee; others charge a separate consultation.

If cost is a barrier, ask about screening clinics organized by breed clubs. These events bring a cardiologist to a central location and offer reduced-rate echocardiograms specifically for screening purposes.

Echo vs. Holter: complementary, not interchangeable

A question that comes up frequently: "Can I just do one or the other?"

The short answer is no — these tests look at different things, and both are necessary for a complete cardiac assessment, especially in breeds prone to DCM.

| | Echocardiogram | Holter Monitor | |---|---|---| | What it measures | Heart structure and function | Heart rhythm over 24 hours | | What it detects | Chamber enlargement, wall thinning, valve disease, reduced contractility | Arrhythmias (VPCs, ventricular tachycardia), rhythm disturbances | | Duration | 20–40 minutes, single snapshot | 24 hours of continuous recording | | Why it matters for DCM | Detects the echocardiographic form of DCM | Detects the arrhythmic form of DCM |

In Dobermans especially, DCM can present first as an arrhythmia problem (detected only by Holter) or first as a structural problem (detected only by echo) — or both simultaneously. Doing only one test means you could miss an entire form of the disease.

Best practice: Screen annually with both an echocardiogram and a 24-hour Holter monitor. They are complementary tools, and together they give the most complete picture of your dog's cardiac health.

The bottom line

An echocardiogram is one of the most valuable tools in veterinary cardiology. It's non-invasive, painless, usually requires no sedation, and gives your cardiologist a direct window into your dog's heart. The key measurements — LVIDd, LVIDs, FS%, and EF% — tell the story of how well the heart is holding up, and serial echos over time reveal whether things are stable, improving, or progressing.

If your dog is in a breed at risk for DCM, annual echocardiograms (paired with Holter monitoring) are the gold standard for early detection. And early detection remains the single most impactful thing you can do — because treatment started before symptoms appear buys the most time.

Ask your veterinarian for a referral to a board-certified veterinary cardiologist (DACVIM-Cardiology) for the most accurate and thorough echocardiographic evaluation.