Anyone have experience with superventricular tachycardia?

Hi.
Our cat Libbie was diagnosed with superventricular tachycardia with an
enlarged heart. I was curious if anyone else has experience or knowledge of
this with their cat. She was prescribed cardizem to help her heart pump more
efficient but it is difficult getting her to take this medication twice a
day. She's 11 years old and I'm concerned that fighting with her to take
these pills twice a day might be as detrimental, because of the stress, then
if she didn't get the medicine. I am a little discouraged by the vet. He
didn't seem to want to explain this disease nor how the medicine would help
her. Libbie also had an infection which seems to have been cleared up with
anti-biotics. She seems much better now since finishing the anti-biotics.

If anyone could give some input on their experience with disease I would be
most thankful !!

Thanks Ricky