Interesting, I also had a brain aneurysm and an ascending aortic aneurysm (found while getting leg fracture surgery) with bicuspid valve. Both are fixed, embolization to fix the brain one, open heart for the aortic. My heart surgery was at 5.2, the size it had when they found it. That was my surgeon’s recommendation, he never mentioned 5.5, he did say 5.0 and above are considered large. I could not wait to have it fixed, had the surgery as soon as appropriate after my leg surgery (3 months). Back to normal life, (that was 4 years ago) just monitoring the valve every year