Go to a GOOD cardiologist who specializes in biscuspid valves. It could be stenosis, or it could be something else. DEMAND a CT with contrast or MRA. I was seen twice in an ER and once by a clinic doctor. After research, I suspected an aneurysm, and demanded a CT on that last trip to the ER. I was right. It's been there for years, and according to old records, was caught on echos and a previous CT, and no one told me. If you have a bicuspid valve, you are prone to aneurysms. Don't give up til you get a good scan done.
Hopefully it's nothing serious, but it's good to rule out the big stuff first.