Heart
Screening Guidelines
My name is Wendy Wallner. I am a veterinarian
in the Atlanta, GA area and am the acting chair of the American
Boxer Club's Health and Research Committee. I have recently instituted
a screening protocol for American Boxer Club members to follow
in an effort to attempt to identify dogs that have:
1)
Congenital heart disease, specifically Aortic or Subaortic Stenosis,
and/or
2) boxer cardiomyopathy
before
these animals are used in a breeding program.
The
screening protocol is as follows:
1
year- auscultation by board certified veterinary cardiologist
(If arrythmia is present - Holter; If murmur present - Echo)
Rationale:
One year is the accepted time for clearance of Aortic/Sub-aortic
Stenosis. This auscultation screening could be performed at the
national specialty and at individual breed club's specialty shows
for a nominal fee. Any dogs with murmurs would be referred to
a cardiologist in their area for further workup.
2
years - Holter monitor, auscultation (Echo if murmur present)
Rationale:
The 2 year check would occur before the animal was used for breeding
and would be useful in picking up dogs with early arrythmias before
they are bred. In some boxers, arrythmias have been detected as
early as 6 months of age.
5
years -
Holter monitor, auscultation (Echo if murmur present)
Rationale:
By 5 years many animals would show signs of arrythmia if they
were going to develop cardiomyopathy since the arrythmia often
precedes clinical disease by several years.
While
we realize that this system of screening is flawed in that some
animals with late onset of cardiomyopathy will have been used
for breeding prior to having detectable signs of disease, and
that the Holter monitor may not be a good predictive indicator
of CM, it will at the very least help create a database for a
large number of "normal" and "abnormal" boxers so that we can
establish breed and age related data for Holter monitoring and
possibly for echocardiography. It will also identify those dogs
affected with Aortic/Sub-aortic Stenosis before they enter the
breeding pool.
Just
as an aside to this, and a rather disturbing one at that, Dr.
Mike O'Grady at the Veterinary College in Guelph has done a study
on Dobes and Cardiomyopathy. In that study, he followed the dogs
for several years. His findings were that any dog that had a single
VPC on ECG or Holter went on to develop CM. We can hope that this
does not hold true for boxers, but I wouldn't count on it.
Wendy
Wallner, DVM
Whirlwind Boxers