Is tachycardia cardiomyopathy curable? can meds be stopped once heart function and heart size return to normal?

May be: If tachycardia induced cardiomyopathy is treated as far as the tachycardia is concerned - answer is yes how even need long term follow up and monitoring . All cardiac function may return in time

Unclear : Yes, heart size and function grossly can return to normal in cases of tachycardia induced cardiomyopathy. Coreg, ace inhibitor +/- aldactone (spironolactone) can effect remodeling and normalization. However, it is not well known if stopping meds will cause reversion of positive gains. Having said that, u and your cardiologist ought to try and have close follow up.