Jetsam sounds a real character. I`m sorry he is progressing with his HCM.
The figures and statements show that the HCM has definitely progressed since
the last scan and he is now at risk of entering heart failure. Plavix has
been added and aspirin because the vet feels he is at risk of a bloodclot
due to his poor heart function so these will help to prevent that.
Spironolactone is for fluid build up due to heart failure.
To answer your questions..
a. Yes, it is vital he takes his medications. Cats are extremely good at
hiding heart issues. The vet feels he is at risk of a clot and CHF and is
giving meds to help prevent this.
b. Plavix is available as clopidogrel as a generic in the UK. I`m not sure
about the US though. There is an alternative called nattokinase which is an
enzyme which dissolves clots. This is a food supplement and you would need
to discuss it with your vet.
c. The meds won't harm him. He may need to start extra medications soon
like fortekor and vetmedin. The meds are helping his heart cope and keeping
him without symptoms.
The murmur is not related to the seriousness of the HCM. Murmur is
turbulence in the blood flow and the atenolol may be relaxing his heart enough
that the grade has gone down.
You need to watch for him entering heart failure. Count his breaths when
resting and it should be under 30. Over 40 is an emergency. He could also
start open mouth breathing which is an emergency as well or be doing 'hard,
not relaxed breaths'.
The rate of progression can never be definitely told. Jetsam could remain
stable now for many years like my Trixi and Maxi have. But you need to be
aware of CHF symptoms and keep an eye on him. He's young and let him play and
enjoy himself. I know it's worrying but he doesn't have a clue he is sick.
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