· 2 min read
How to read a cat's echocardiogram report
A walk through the parts of a feline echo report a buyer can actually use — what the wall measurements are, what 'equivocal' means, and what to ignore.
Anna Bronsky
Co-Founder of TrueKitten, a verified Maine Coon marketplace
Short answer: you are looking for four things — the date, the cardiologist, the left-ventricular wall measurements, and the stated conclusion. You do not need to interpret the numbers yourself. You need to confirm a qualified person interpreted them, for this cat, recently.
The four things that matter
- The date. HCM is progressive, so the report describes that day. See how often breeding cats should be rescreened.
- Who performed and read it. Look for a board-certified veterinary cardiologist; you can verify a specialist independently.
- The measurements. A feline echo reports the thickness of the left ventricular wall in diastole, usually in millimetres, often as IVSd (the septum) and LVPWd (the free wall).
- The conclusion. Most reports state one in words — normal, equivocal, or consistent with HCM.
What the wall measurements are doing
HCM is thickening of the heart muscle. The cardiologist measures how thick the left ventricle’s walls are when the heart is relaxed and full, then judges those numbers against the cat’s size and the reference values in use.
You are not expected to grade this yourself, and any guide that hands you a single millimetre cutoff is oversimplifying — reference values vary between laboratories and body sizes, which is exactly why interpretation belongs to the cardiologist rather than the reader.
“Equivocal” is a real answer, not a dodge
A report can conclude that a heart is borderline: not normal, not diagnostic. That is an honest finding, and it usually means “rescreen sooner.” A breeder who shows you an equivocal result and explains their plan is being straight with you. Treat it as more trustworthy than a line that has only ever produced perfect results.
What a report cannot tell you
It cannot tell you about the future, and it cannot substitute for the genetic test — the two answer different questions. A cat with a normal echo today can develop HCM later; that is the nature of a progressive, late-onset disease.
The practical check
If you take one habit from this: confirm the report names the cat, ideally by microchip. A document that cannot be tied to the animal you are buying is not evidence about that animal, however impressive it looks.
Keep reading
Yes. UC Davis puts HCM incidence at 5.4% in Maine Coons without the A31P mutation and 5.4% in cats with it — the DNA test cannot see the heart.
An echocardiogram is a snapshot, not a certificate. Why breeding cats are rescreened on a schedule, and how to tell whether a result is still meaningful.
Negative, carrier and affected are three different things, and two of them get confused constantly. How to read an A31P result without over- or under-reacting.
