A cardiology report is a sheet full of abbreviations and numbers, and the owner usually leaves the consulting room with one sentence they remember. This article explains what those numbers mean, so that you can follow your dog's condition over the years yourself.
The point is not to replace your vet but to understand the report you already have in your hand.
What the report actually contains
A proper cardiology report has four parts:
- Details of the dog: name, microchip number, date of birth, age on the day of examination
- Findings on auscultation: whether a murmur is heard and of what grade
- Ultrasound measurements: a few numbers about the size of the heart
- Conclusion: the stage of the disease and a recommendation
If the microchip number or the dog's age is missing, the report cannot be tied either to the dog or to a point in time. For a breeding report that makes it worthless.
grade of the murmur
The first item is the loudness of the murmur, on a scale from 1 to 6. It is written as a fraction, for example 3/6, meaning grade three out of six.
The grade tells you how loud the sound is, not how damaged the heart is. A dog with grade 4 may have a heart of normal size, and a dog with grade 2 an enlarged one. That is why an ultrasound is almost always done alongside the listening.
The measurements that decide
This is the part most owners skip, and it is exactly what determines whether the dog gets treatment. Three numbers come up most often.
LA/Ao is the ratio of the size of the left atrium to the aorta. The aorta is used as a yardstick because it does not change, so it shows how far the atrium has widened. The threshold is 1,6.
LVIDDN is the diameter of the left ventricle at the moment of filling, adjusted for the dog's body weight. The adjustment exists so that a five-kilo and an eight-kilo dog can be compared. The threshold is 1,7.
VHS is the size of the heart measured on an X-ray, expressed in vertebrae. The threshold is 10,5.
If you have seen these numbers in your report and they do not exceed the thresholds, the dog's heart is not enlarged, no matter how loud the murmur is.
The stage: what the conclusion says
On the basis of all the above, the cardiologist places the dog in one of the stages of the international classification. The labels are letters.
- A: the dog belongs to a predisposed breed but has neither a murmur nor changes. Every Cavalier is here from birth.
- B1: a murmur is present but the heart is not enlarged. No treatment is started, check-up once a year.
- B2: a murmur is present and the heart is enlarged, but the dog has no symptoms. This is where treatment begins.
- C: heart failure has developed with visible symptoms.
- D: heart failure that no longer responds to standard treatment.
The whole point of annual check-ups is to catch the moment of transition from B1 to B2. That transition cannot be noticed at home, because a dog in stage B2 looks entirely healthy.
Why B2 is the turning point
For a dog to be placed in B2, four things must coincide: a murmur of at least grade 3, LA/Ao of 1.6 or more, LVIDDN of 1.7 or more, and VHS above 10.5.
Those thresholds are not arbitrary. They were set on the basis of a large clinical trial which showed that starting medication at exactly that moment significantly delays the onset of heart failure.
The medicine introduced then is most often pimobendan. The dose and the combination are determined solely by the vet.
How to track reports over the years
A single report tells you less than a series of them. That is why a simple record is worth keeping.
For each examination note down:
- the date and the dog's age
- stepen šuma
- the LA/Ao and LVIDDN values if measured
- the stage from the conclusion
- the dog's weight that day
A photo of the report on your phone is quite enough. A cardiologist who can see how the numbers changed over three years has a far better picture than one looking at a single sheet.
What the report does not tell you
A few common misunderstandings are worth clearing up.
The report does not predict how long the dog will live. The stage describes the situation today, and the speed of progression differs from dog to dog and cannot be calculated in advance.
A clear report does not hold good forever. In Cavaliers the condition changes, so a report older than a year says nothing about the dog today.
The report says nothing about syringomyelia. That is a separate examination, by MRI, and it is not visible on the heart.
A report for breeding
For a dog used in breeding the report must meet additional conditions:
- the examination was carried out by a cardiology specialist, not a general vet
- the dog was at least two and a half years old at the time of examination
- the report is no more than a year old at the time of mating
- the conclusion states that no murmur is audible
- the paper carries the name, signature and stamp of the doctor
When you ask for the reports on a litter's parents, ask for exactly this. The sentence “they have been examined and everything is fine” without a document is not a report.
Conclusion
A cardiology report is more readable than it looks once you know that three numbers and one letter matter: LA/Ao, LVIDDN, VHS and the stage in the conclusion. Everything else is description. For a Cavalier owner the most valuable habit is to record those figures year after year, because change over time says more than any single examination.
Note: this article is informational and does not replace examination and advice from a veterinarian. Interpreting the report and deciding on treatment is done solely by the vet, preferably a specialist in cardiology.
Related
- Mitral valve disease (MVD) in Cavaliers: stages, signs and treatment
- Heart murmur in Cavaliers: what it means and when it is a cause for concern
- Syringomyelia and Chiari-like malformation in Cavaliers
- Why Cavaliers scratch their neck and shoulder — when it is a sign of illness
- Which health tests are required for the parents of a Cavalier litter
- The expected lifespan of the Cavalier and what affects it
- A schedule of veterinary check-ups by the age of a Cavalier
- Eye problems in Cavaliers: what occurs and how to recognise it
- Patellar luxation in Cavaliers: the slipping kneecap of small breeds
- Ear problems in Cavaliers — why drop ears need more care
- MRI screening for syringomyelia: when, how and what the report means
- Cavalier vaccination and deworming: schedule by age
- Living with a Cavalier diagnosed with MVD
- Health of the Cavalier King Charles Spaniel — an overview of all topics
- Puppies for sale from a kennel with health-tested parents
