No, she hasn't had a blood test since her first vet visit. I will ask the vet. She is a very picky eater at the best of times, but does enjoy sprouts and greens. We decided that we would feed these first and then give them seeds/pellets from now on. I do know the vet has mentioned heart issues have happened to birds with the protozoa she carries in her gut, which so far has been very resistant.Has your tiel had a full blood test done to check blood levels for fats and lipids, etc?
I wonder if tachycardia could be diet related?