Hey there,
First of all, good luck on your upcoming TEE. The TEE is a procedure in which the doctor will look at your valves through your esophagus. It's not as bad as it sounds (believe me, the first TEE I had, I was all freaked out before: "I have to swallow WHAT?"), but it is an echo that is essentially much close to your heart, and your doctor can see your valves much better than he/she can through a traditional echo or even an angio.
In my case, when my mitral valve began to fail four years ago, my cardio did an echo first, then an angio, and then a TEE. He wasn't quite convinced my valve was bad enough for surgery, but the TEE result was the one that sent me to a surgeon.
Hope this helps.
Best,