You have a bicuspid aortic valve (“congenital anomaly” - most common one - present in about 2% of human population). It turns out that not only does having a bicuspid aortic valve result in early valve disease (stenosis, regurgitation or both), but it is also associated with an abnormal weakness of the most proximal portions of the aortic “root” and ascending aorta. It’s known as “bicuspid aortopathy”. It is a form of annuloaortic ectasia, and any dilatation of the proximal aorta is usually associated with sinotubular effacement (that’s just a descriptor, not a pathology). After much population-based research, it has been determined that an aortic root or proximal ascending aortic diameter of ≥4.5 cm portends elevated risk of further dilatation and aneurysm formation over the long term. Thus, it is recommended that in bicuspid aortic valve patients whose aortas are larger than that, the proximal aortic root be replaced as well. It’s more of a gray zone below 4.5, but I’ve cared for patients who’d had smaller aortas at the time of bicuspid aortic valve replacement, and then a few years later, needed to go BACK to the OR for replacement of an ascending aortic aneurysm. That is clearly a sub-optimal situation. With you proximal ascending aortic measurement of 4.6 on your recent CTA, it is most prudent to replace both the valve, root and proximal-most portion of the ascending aorta."