Heart Defect - Eye Problems

I have a cat that is 3.  She was diagnosed with an enlarged heart (3x normal size, which takes up the chest cavity) about 2.5 years ago.  She has always slept more and had a little harder time breathing.  This was diagnosed when she seized from anesthesia to fix another issue and x-rays had to be taken.

About 2 weeks ago I noticed with sudden sun light one eye dilated significantly more than the other.  This was only for a short period of time.  Then yesterday she started breathing quick and it was so heavy that you could see her chest collapse right after she would take a breath.  At that time I also noticed that one eye appears significantly larger than the other.  The episode laster a couple hours.  After about 12 hours her eyes are still the same but her breathing has gotten better.

Is she going into congestive heart failure?  We were told that this was inevitable and would happen most likely when she stopped growing around 1 year old.

[Savas]

It sounds like she's suffered a stroke or cerebral event. I'm no expert on feline heart conditions, but my limited understanding does recall that this is something that can happen from conditions like this.

I hope it isn't finally that time. It's almost impossible to prepare for something like this, I hope kitty gets mucho more time.