I would recommend switching to a wet food. Wellness, Innova, etc. All are "better" than dry foods, in the sense that they have much higher levels of water, and will keep your cat hydrated.
The risk you run with a cat with HCM is dehydration. You can't rehydrate a cat with HCM as easily as you would a regular cat; too much injected fluid can push them into pulmonary edema and subsequent heart failure.
I know a few of us have been in the kidney failure / HCM struggle, and I did quite a bit of research on the topic... I'll shoot you an email with what I found.
From: vllevan <vllevan@...
Sent: Friday, August 10, 2012 1:48 PM
Subject: [FH] Newbie with more questions
Last month my 7 month old kitten Illyana was dx with hypertrophic
cardiomyopathy. She was started on ½ 12.5mg Flurosemide, ¼ 5mg Benzapril
and ¼ 25mg Atenolol. She is also on Cardiostrength (CQ10) ¼ of the capsule
twice daily and Felovite II.
She had her one month follow-up with the specialist and he's revised the
dx. It's now only cardiomyopathy it seems due to improved cardiac
parameters. The wall of her heart has gone from 6mm to 4mm and he's said
there is: improved left ventricular changes, turbulence within the left
ventricular outflow tract and improved left atrial size. Her next recheck
is in 3 months. Both the specialist and my vet are very happy with her
progress but I'm still very guarded. I still worry about her as I know no
one can predict the course this disease will take in their kitty.
I'm also concerned about her food. She's been on wellness dry and soft
kitten food. She does get some of our other cat's dry, which is Purina
Naturals. Should she be on something different –low salt or higher in
nutrients. She is a picky eater, I tried other brands slowly as I wanted to
"test" some options for a transition to adult food and then have the entire
household on the same food. Any suggestions for her and her "cousins"?
Thank you to everyone who has offered advice and thoughts as Illy and I
make our way through this journey
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