Not sure how much help I can be here, but I'm assumming you're talking about a mild leak that has occurred post op on your prosthetic valve? I've heard of small leaks with replacement valves in all positions. Just curious to know when you had your AV replaced and what kind of valve you received. Also, it sounds like your TA condition, from the little I've read, might have played a part, since it involves enlargement of the large arteries and any changes to your aorta post op might have made a perfect match between your aorta and your aortic valve difficult to achieve. Seems like a stentless tissue valve with a dacron conduit would have been a good solution, but alas, I talk out of my non-mdeically trained arse here. I can tell you that my bicuspid aortic valve was moderate for years and did not limit me from doing very strenuous aerobic exercise (no super heavy lifting, of course), before it became severe. However, I didn't have your vascular condition, which perhaps makes mild regurgitation a more serious concern. But generally speaking, a mild leak is not considered a serious condition, just one that warrants monitoring.