"yngver" wrote in message
...
We just had our six month follow up echo for our cat who was diagnosed
with very mild HCM in May. I'm having trouble understanding the
results and I hope you can shed some light while I wait to hear back
from the cardiologist to clarify.

Our cat was diagnosed with mild HCM with mild LV outflow tract
obstruction and secondary mitral regurgitation, also mild thickening
of the anterior mitral valve leaflet. She had a grade 2 murmur. She
has been on atenolol, 1/4 tablet twice a day which lowered heart rate
to 140-150 (goal range) and eliminated the murmur.

These latest echo results show no progression of the HCM, no SAM, no
LVOT obstruction, no heart murmur. However, what I don't understand is
that the cardiologist said the mitral valve is thicker (moderate now
vs. mild) and there is still mild mitral regurgitation. I was told
this is separate from the HCM. The conclusion was "Stable disease.
Potential for progression of mitral insufficiency. Recheck echo in one
year."

I'm having trouble understanding what is causing the mitral
insufficiency if it isn't from HCM. My vet just said the cardiologist
didn't explain it so he will have to talk to her. She did write "there
has been no significant change in the degree of LV hypertrophy or any
other cardiac size measurements" so I thought at first that meant
nothing had gotten worse.

I hope Phil reads this and can comment, or anyone else who has any
ideas on what this means. I haven't been able to find anything about
this kind of valve problem in cats. Thanks for any advice.
-yngver

Mitral insufficiency can occur as a primary condition or secondary to HCM.
Mitral insufficiency in cats is almost always caused by thickening of the
valve leaflets which prevents the valve from closing properly. This allows
blood to leak through the valve from the left ventricle to the left atrium
during systole (regurgitation). Thickening of the valve leaflets can be
independent of HCM and is usually caused by myxomatous degeneration
(myxomatous atrioventricular valvular degeneration) which is usually
progressive-- however, the rate of progression can be very slow. I don't
know of any drug that slows the progression of mitral valve degeneration.

I'm sorry I can't be more helpful.

Best of luck,

Phil