Feline EchoMeasurement Guide
A plain language guide to the common terms and measurements found on a cat echocardiogram report.
Echo Shows Structure
It helps evaluate heart walls, chambers, and blood flow.
Numbers Need Context
No single value should be interpreted by itself.
Conclusion Matters
The cardiologist’s final review is the key result.
How to Use This Guide
This page is educational. It can help families read common echo terms, but it does not replace a veterinary cardiologist’s interpretation.
Echo reports may use different formats and abbreviations. The final meaning depends on the full exam, the cat’s age, body size, blood pressure, health status, and the cardiologist’s review.
Feline HCM: Key Measurements
A simple visual guide to the main echocardiographic measurements used when screening cats for hypertrophic cardiomyopathy.
1. Heart Anatomy
- Aorta
- Left atrium (LA)
- Mitral valve
- Interventricular septum (IVS)
- Left ventricle (LV)
- Left ventricular free wall (LVFW)
2. Long Axis Measurements
- IVSd
- =
- Interventricular septal thickness in diastole
- LVIDd
- =
- Left ventricular internal diameter in diastole
- LVFWd
- =
- Left ventricular free wall thickness in diastole
- LA
- =
- Left atrium
- Ao
- =
- Aorta
3. Short Axis Measurements
- IVSd
- =
- Interventricular septal thickness in diastole
- LVIDd
- =
- Left ventricular internal diameter in diastole
- LVFWd
- =
- Left ventricular free wall thickness in diastole
4. What Veterinarians Look For
| Measurement | What it helps assess |
|---|---|
| IVSd and LVFWd | Wall thickening |
| LVIDd | Chamber size |
| LA and LA:Ao | Left atrial enlargement |
| Overall pattern | Whether the heart shows changes consistent with HCM |
What Cardiologists Review Together
A feline echocardiogram is not a simple pass or fail number. The full pattern matters.
Wall Thickness
Septal and ventricularwall values are reviewedwith the full heart image.
Chamber Size
The left atrium and leftventricle are checked forsize and shape changes.
Blood Flow
Doppler can help showflow direction, turbulence,or possible obstruction.
Clinical Context
Blood pressure, thyroidstatus, age, and examfindings all matter.
Common Terms on BearMary Reports
These phrases help families understand the difference between recorded measurements and the cardiologist’s final interpretation.
How to Read NovaBear’s HCM Screening Report
Annotated page 1. Key measurements and what is generally reassuring or worth interpreting with the full echocardiogram.
1ECG and rhythm
- Heart rate: 230 bpm
- Rhythm: regular
A regular rhythm is reassuring. Heart rate can be elevated during an exam because cats are often stressed, so it should be interpreted in clinical context.
2LVPWd, left ventricular free wall thickness
- 3.4 mm, 2D
- 3.64 mm, M mode
This measures the thickness of the left ventricular wall. In HCM, this wall becomes abnormally thick.
Borderline: 5.0 to 5.5 mm
Concerning: > 5.5 mm
3IVSd, interventricular septal thickness
- 3.5 mm, 2D
- 3.96 mm, M mode
This measures the thickness of the septum between the ventricles. Thickening here is a key sign looked for in HCM screening.
Borderline: 5.0 to 5.5 mm
Concerning: > 5.5 mm
4Left atrial size
- LA: 11.7 mm
Left atrial size helps show whether the left atrium is enlarged. The value shown here is presented as reassuring on this page and is not used alone to diagnose HCM.
5Chamber dimensions
- LVIDd: 13.04 mm
- LVIDs: 8.02 mm
These describe chamber size when the heart is relaxed and when it is contracting. The values shown here are presented as reassuring on this page and are not used alone to diagnose HCM.
6Why section 3 matters
This follow-up section is mainly used when wall thickness is above 5.5 mm. NovaBear’s wall thickness values are below that threshold, so this section is not triggered by the values shown here.
Normal Echocardiogram
The overall ultrasound review did not identify abnormal heart findings on that exam.
No Evidence of HCM
No evidence of hypertrophic cardiomyopathy was noted at the time of screening.
Measurements
The recorded values support the cardiologist’s interpretation but are not read alone.
Recheck in One Year
A repeat echocardiogram is recommended to continue monitoring over time.
What a Clean Result Means
We use the word clean carefully. It describes the most recent screening result, not a lifetime promise.
Clean on This Exam
No evidence of HCM was reported on the latest echocardiogram.
Monitoring Continues
Repeat screening helps follow heart health as cats mature.
Not a Guarantee
A clean result today does not rule out changes later in life.
Core Echo Measurements
These are common terms families may see on feline heart ultrasound reports. The plain meanings below are simplified for general understanding.
| Term | Plain Meaning | Why It Matters |
|---|---|---|
| IVSd | Interventricular septum thickness in diastole. | Helps assess whether the wall between the ventricles is thickened. |
| LVPWd | Left ventricular posterior wall thickness in diastole. | Reviewed with other wall measurements when screening for thickened heart muscle. |
| LVFWd | Left ventricular free wall thickness in diastole. | Another wall thickness value used to understand the left ventricle. |
| LVIDd | Left ventricular internal diameter in diastole. | Describes the chamber size when the ventricle is filling. |
| LA | Left atrial size. | Left atrial enlargement can be important when judging disease progression. |
| Ao | Aortic root size. | Often used as a reference when comparing left atrial size. |
| LA to Ao | Ratio between the left atrium and the aorta. | Helps evaluate whether the left atrium is enlarged. |
| FS | Fractional shortening. | Gives information about how the left ventricle changes size during contraction. |
| HR | Heart rate during the exam. | Helps the cardiologist interpret the exam conditions and heart function. |
| Doppler | Ultrasound assessment of blood flow. | Can help identify abnormal flow patterns or obstruction. |
IVSd
Septum ThicknessHelps assess whether the wall between the ventricles is thickened.
LVPWd
Posterior WallReviewed with other wall measurements when screening for thickened heart muscle.
LVFWd
Free WallAnother wall thickness value used to understand the left ventricle.
LVIDd
Chamber SizeDescribes the chamber size when the ventricle is filling.
LA
Left AtriumLeft atrial enlargement can be important when judging disease progression.
Ao
Aortic RootOften used as a reference when comparing left atrial size.
LA to Ao
Size RatioHelps evaluate whether the left atrium is enlarged.
FS
Contraction ChangeGives information about how the left ventricle changes size during contraction.
HR
Heart RateHelps the cardiologist interpret exam conditions and heart function.
Doppler
Blood FlowCan help identify abnormal flow patterns or obstruction.
Frequently Asked Questions
Short answers to common questions families may have after viewing an HCM report.
Can I diagnose HCM from one number?
No. Echo measurements need to be interpreted together with the full ultrasound image, the cat’s health status, and the cardiologist’s conclusion.
Does clean mean the cat will never develop HCM?
No. A clean result means there was no evidence of HCM on that specific exam. Ongoing monitoring is still important.
Why does the report recommend recheck in one year?
Some heart conditions can develop over time. A planned recheck helps monitor heart health as the cat matures.
Is DNA testing the same as echocardiogram screening?
No. DNA testing checks selected known variants, while echocardiography evaluates the actual heart structure and function at the time of the exam.
Why are blood pressure and thyroid status mentioned?
Some conditions, including high blood pressure and hyperthyroidism, can cause heart wall thickening and should be considered before diagnosing HCM.
Why publish the report pages?
We share them to make the screening process more transparent and easier for families to understand.
Sources and Further Reading
These references are helpful starting points for understanding feline cardiomyopathy and heart ultrasound screening.
Explore Our HCM Screening Pages
View our cats’ screening reports, learn what HCM means, or return to the main HCM screening overview.